1985 200x starting issues.

[Atc 200x 1985]

Hello, I am having trouble starting a 1985 Honda ATC 200x. I have rebuilt the top end brand new wiseco 10.25:1 piston and all new gaskets. I know I was not supposed to grind the valves but did not know that until after I have already ground them. Completely stock other than the piston in it. It has spark but weak like not able to be seen in a shaded area outside but I think it is just enough to start. I have replaced the ignition coil and the CDI box and the CDI pickup on the cam still no avail to get a stronger spark... But it still wants to start but it is not able to you can hear it fire like 3 times then die and every other kick it will do that. the carburetor is stock with 108 main jet 40 pilot jet the idle mixture screw is missing the washer and o ring so I don't know if that has anything to do with it the needle is on its 4 setting from the bottom where it should be I think. valves are adjusted to .003 both fire and cam timing are correct I believe. One thing is that before I got a new spark plug the old one that was in it was working but around the electrode area it was grayed and that means that it is running too rich. so does anyone know what is going on with it? I would like to get it going again. If I ever do get it running again I have a dg or either a cobra exhaust for it and I plan to upgrade the carburetor from stock to like a 32 mill or whatever is 2 steps above stock. Also, should I run 93 in the engine now since I upgraded the piston? thanks.

[Atc 200x 1985]

Ok I made a mistake lol I put the piston in wrong... I thought the arrow met intake but I was reading around and it met direction of flow so I fixed that and it runs correctly now. It is getting too much fuel and is hard to start but it runs. any ideas on how to fix that? I have the needle set at the 4th position and the idle mixture screw is 2 1/4 turns out where it is supposed to be, it has a 108 main and 35 pilot. does anyone know the stock jet sizes?

[ps2fixer]

The weak spark might be the cause of hard starting. A spark tester would validate if it's weak or not since it's really hard to tell on a spark plug.

Basically you hook the coil wire up on this, clamp it to the head and set a 6mm gap, if you get spark it's good, if not you have something in the ignition system not right or too weak (bad coil, spark plug cap, weak sator/flywheel, poor connection, corroded wires etc).

Ebay Listing -> https://tinyurl.com/qn4v4hl

That's just looking at the ignition. Jetting the carb makes a huge effect too, don't really know what a good base line for your mods are though.

Here's the stock jet specs (and a ton of more info) on my site.

https://atvmanual.com/honda/atc200x/1985-specs

[shortline10]

Pilot jet is supposed to be a 40 , 35 is way to small .

[Atc 200x 1985]

shortline10 ok thanks I will try a 40 in it. I took the fuel petcock out and it does not have a fuel filter in it so it could be clogging up the jets cause I can shake the machine and it will start again. ps2 fixer I do have a spark tester its one of them with the light in it is that what you are talking about? when I have tested it before it lights up so it may just be normal for it to have weak spark.

[ps2fixer]

A light doesn't really tell you must, it just has some sort of spark. You want a metering device. I pasted a link to an ebay listing to show it, here's the link again. Basically you hook the plug wire to it, other end to engine head, set a 6mm gap and see if it can jump the gap and if it looks healthy or not. If it can't jump the 6mm gap, the ignition system has something in it that's making the spark weak like bad spark plug boot etc.

Ebay Listing -> https://tinyurl.com/qn4v4hl



Also, besides carb specs, my site has the ohm specs for the different ignition parts. Linked it again below. Exciter should be Black/Red to ground, pulse generator should be blue/yellow to green/white. Primary coil in ignition coil is where the black/yellow wire connects to the coil, to the ground/body of the coil. Secondary is ground to spark plug cap end (spec is with or with out cap). With the cap, generally they read about 5k ohms more (5,000 more ohms). If there's an electrical problem, it should show up in those tests. Physically things have to be good too, but the electrical test doesn't know any difference if like the pulse generator has too big of a gap or not.


https://atvmanual.com/honda/atc200x/1985-specs

[Atc 200x 1985]

Ok that link is not working. I do have a meter just like a fluke meter correct? If so when I get home I will test and post a response to what the readings are.

[ps2fixer]

Weird, never had problems linking before on here, maybe the recent changes broke some links. Here's a url shortened version, this one should work. Never had to use these before.


https://tinyurl.com/qn4v4hl

[MrConcdid]

Also, I had a plug that would spark outside the cylinder, but not under compression in the cylinder, I changed the plug to a new NGK on a whim, and whamo! it runs great.

MrC.

[Tri-Z 250]

If there’s one over stock item I have in my back pocket besides race fuel, oil/filters, it’s the love of NGK’s for every machine.
Consider the cable and ends connecting the plug as well, if it’s original.
Now get a ride report with some pics. Here’s to ya:beer

[Atc 200x 1985]

Ps2 fixer ok it is working now I’ll look I to buying it. McConcdid I bought a brand new iridium ngk spark plug cause I’ve read is they take lower voltages to get more consistent spark. Tri-Z 250 I will replace the ends to all the cables and see if that helps. Also for everyone I went back to a 40 jet and it stopped even trying to start so I believe it is was to rich so I’m going to go back to a 35.

[ps2fixer]

The machine wasn't designed for Iridum so I'd run the standard plug personally. It's like the Toyota's that call for the double ground plugs, put an Iridium in them and less power, worse mpg, just overall not as good as the OEM designed plug. Have had two or three different people have the same issue and running the right plug was the thing that fixed it. All the plugs were NGK or Denso btw. I don't know why it effected it, just know it does. The voltage thing I don't really buy, the gap and resistance of the air is what determines the voltage, atleast for my limited understanding of how it works. I'm guessing it's like the "back pressure" thing, a 4 stroke doesn't need back pressure to run right, look at top fuel drag racers. You do need a balanced system, intake, exhaust, and the air/fuel ratio needs to be correct for the whole rpm range.

[Tri-Z 250]

Good info for thought,? Never had a problem but I get the equivalent plugs to stock spec. The plug end of the ignition wire can over time with over service wear contact end. Typically in two strokes, but I chop 1/4” off and reattach the cap if it’s solid shape.

[ps2fixer]

I just worked with a guy recently with a no spark issue. One thing handy is to use a multi meter to test the spark plug wire off the ignition coil and also test the spark plug cap (around 5,000 ohms is normal). If the cap doesn't give connection, then it's wasting energy or won't even spark.

I'm starting to really push the ohm parts out before replacing. Like my T100 pickup, I have a miss in it, comes and goes relating to temp. I have parts machines, so I just started swapping parts, igniter, coils, ecu, etc. I got to the point where the only ignition related part left is injector. Looked up the specs, ohmed it through the ECU connector and all test good except #2 shows 1.2k ohms, yep bad injector. Probably could have saved myself a lot of time if I just ohmed the parts out to diag the problem.

[MrConcdid]

Ps2fixer, I feel the same way, I found a list of values the cdi box needs to run. I omh each pin, if I don't have the correct value there is the problem. I found a good stator and a bad on off switch this way.. never had to take anything apart to find the problem, just better detective skills.
MrC.

[ps2fixer]

Yea, the CDI plug is like the best place to test for problems, if it fails the test at the plug then there's clearly a problem either in the harness or part, retesting right at the part will rule out the harness or not.

FYI, most service manuals give ohm specs for the CDI itself but those are based on using an exact meter, a different model/brand might give different readings, so the test is likely unreliable. One of those parts where you test everything else, if all tests good then CDI is replaced. Not the best way to do things, but it requires a special tester that's not exactly cheap.

[Atc 200x 1985]

Thanks for the info I will post a response on what the readings are. I replaced all the wire ends and that helped a little and I had the float set wrong so now I am able to run the stock 40 jet in it again. I have not tested if that helped the problem but as soon as I do a test I will post what happened.

[Atc 200x 1985]

Ok here are all the readings. Primary ignition coil 1.0-1.1, secondary 2.9k-3k. CDI 1.6k Pulse generator values 95.6 hope this helps yall find if anything is bad.

[ps2fixer]

Primary is slightly high, but probably just an inaccurate meter, it's close so most likely fine
Secondary coil is at the bottom end range of acceptable, so in theory should work yet
pulse generator looks like a perfect reading, so it sounds good.

Not sure what the CDI reading means exactly, there's 5-6 wires lol, the test process is laid out as a table in the service manual lol.

Did you grab the spark tester? I'm just wondering if that shows you have solid spark. You can run the engine with the tester hooked up. Manual says, if you directly ground the output pin, set to 6mm gap for testing, if you connect it to the spark plug, set to 4mm gap. Could start with a smaller gap and adjust bigger if it's too hard starting. You can physically see what the spark is doing at different rpm's and such. You could also swap parts back to stock and see if there's any changes, keep the best results in the machine. If spark tests good, I'd say it's a mechanical issue, ignition timing, mechanical timing, fuel flow, carb jetting (too lean/rich), etc.

I didn't see a reading for the exciter coil (black/red wire to ground), that's the power source for the CDI and ultimately the ignition coil/spark energy. Reading is done on engine side of the connectors.

[Atc 200x 1985]

Sorry I thought the Manual met to test the thing on the cam lol here are the correct readings for the cdi. I converted the cdi box thing to a round plug instead of the square style I don’t know if that would mess it up though it’s been like this for 5-6 years. Anyways here are the readings for the 200s style plug that is on it. Sw-ext 7.10, SW-E1 23.50, SW-E2 23.50,
SW-IGN infinity, EXT-SW 6.70, EXT-PC 24.50, EXT-E1 6.67 phew��, EXT-E2 6.67 phew again��, EXT-IGN infinity,
PC-SW infinity, PC-EXT infinity, PC-E1 infinity, PC-E2 infinity, PC-IGN infinity,
E1-SW infinity, E1-EXT infinity E1-PC 7.51, E1-IGN infinity,
E2-SW infinity, E2-EXT infinity, E2-PC 7.51 E2,IGN infinity,
IGN-SW infinity, IGN-EXT infinity, IGN-PC infinity, IGN-E1 infinity, IGN-E2 infinity. There are all the readings for the cdi test points.

[ps2fixer]

Not sure what service manual you have, but here's the Honda one. As it says, it requires a special tester though, so your meter might not give the right figures. It doesn't show the pin out for the 84-85 CDI.


https://i.gyazo.com/b50273dc88b9c334622eb2b7984dd450.png

[Atc 200x 1985]

https://www.motoelectrical.co.uk/uploads/product/zoom_RM02004.jpg I don’t have that type of cdi unit I have the 200s type the round plug. I have a climber manual and the original manual that came with the three wheeler. I have just a multimeter set to ohms. That picture is the type of cdi I have.

[ps2fixer]

Yea, they are the same, just different connectors. 83 got the 4+3 squared off connector while 84-85 200x got the round style. Basically all 84-85 Honda's got that connector and 86 it switched to the 4+2 style connector that was used for 10-15+ years.

Anyway, the readings match the ranges that Honda gives, so in theory the CDI is good, but you can't really test the capacitor inside and such. I think the test only works to say if it failed the test, it's 100% bad, but if it passes the test, it does not mean it's actually good. Like testing the pulse generator, it can pass the ohm test, but if the gap is too big, it won't work.

Btw, what's the numbers on your CDI? It's possible you have one for the wrong machine, like a 250es one wouldn't work on the 200x. Should be CF439 (965) for the stock unit.

Also, how exactly did you get that 1.6k reading for blue/yellow to green/ground? If you did it at the CDI connector on the harness side, might be a bad wire in your harness or bad connection. You should have very close to the pulse generator spec, your test before said 95.6 ohms, so 1.6k means the wiring has 1,500 ohms of resistance if I'm guessing this correctly.


Besides the curve ball 1.6k ohm reading, seems like the electronics test electronically good.

[Atc 200x 1985]

Yes I did to that on the harness side for those wires I believe that the cdi pickup thing on the cam is for a 200s I have the original one let me put that on there and I’ll get back to ya.

[Atc 200x 1985]

A little different on the starting seems to want to start easier now. Also the cdi box is correct for this Machine Cf439 is what it is.

[ps2fixer]

The 84+ ATC200S one should be very close, but the part number is different for some reason. Pretty sure the ohm spec is the same and it's the same basic design.

If it's from an ATC185S or ATC200 it's the same part number. Also you can buy the whole rotor yet from Honda, but I'd think yours is fine as long as the magnet is still good.

https://www.partzilla.com/product/honda/30220-427-154?ref=39d7115b19c2e7d44e80e4e860c86fffc6a46b39

Make sure you set the gap on rotor to pickup coil (pulse generator) to 0.3-0.4mm, that's the spec, just like a points engine. Might have to bend the mounting bracket a little if there's no adjustment.

[Atc 200x 1985]

Yeah the magnet is fine I may not have the gap set correctly on it I’ll set it then get back to ya.

[Atc 200x 1985]

What would 0.4 look like on a feeler gauge? Im not a metric guy send me a picture of 0.4 please.

[ps2fixer]

Just have to convert mm to in, I can remember the mm numbers so much easier than inches lol. Like spark plug gaps, ez 0.6-0.7mm.

Google converts the numbers well =).

0.3mm = 0.0118 in
0.4mm = 0.0157 in

so 12 thousands to 16 thousands

[Atc 200x 1985]

Ah ok 0.012 would be correct?

[Atc 200x 1985]

Ok I set it to .012 nothing different I don’t think it is getting enough fuel for it to start now cause it barely wants to start and I give it throttle it will die any ideas? The float is supposed to be at .55 inches I think I have it correct but I could be wrong.

[ps2fixer]

yea should be good

[Atc 200x 1985]

Ok now what is happening is I turn the idle speed thing all the way out and it will want to start but I can move it in a half a turn in and it won’t wanna start. any ideas, Is it to lean or to rich? I have the air box hose thing on it too.

[ps2fixer]

You can test if it's too lean by choking it a little with the idle screw in more. If it's easier, then it's probably closer to the ideal mix. Also engine temp effects tuning, that's the whole point of a choke, it's only for cold starts.

[Atc 200x 1985]

I done that and it didn’t want to start but when I went back it wanted to start again. Could it be too rich?

[yaegerb]

I done that and it didn’t want to start but when I went back it wanted to start again. Could it be too rich?

Ok, sorry I am joining the party late.....there is a lot of pages here but not a lot of progress.
1. Do you have a blue spark?
2. Do you have fuel in the float bowl?
3. Do you have any clogs in the air intake?

[Atc 200x 1985]

I have blue spark, I am getting fuel to the float bowl but I don’t know if I am getting enough, and I do not have any clogs in the air intake.

[MrConcdid]

If you have spark and fuel
than its either compression or timing
I bet the timing is out set TDC, check valves Better to be a little loose than to tight at TDC, put in a brand new NGK plug.
If that doesn't light it off than you have low or no compression.

MrC.

[Atc 200x 1985]

Ok I’ll try all that it is probably out of timing cause I could never set it on point. Is there a special link on the cam chain that is supposed to be on the o on the cam sprocket? I rebuilt the engine but didn’t Hone the cylinder should I have done that?

[yaegerb]

Ok I’ll try all that it is probably out of timing cause I could never set it on point. Is there a special link on the cam chain that is supposed to be on the o on the cam sprocket? I rebuilt the engine but didn’t Hone the cylinder should I have done that?

you put a new piston in but you didn't bore or hone the cylinder? There is no special link on the cam chain. There is a thread on 3 wheeler world that tells you how to set the timing.

[Atc 200x 1985]

no Boring or honing was done when I installed the new piston. should I have honed it? Sorry I should’ve made that clearer.

[Atc 200x 1985]

I have good news it starts again but as soon as I give it throttle it will die to rich or to lean?

[ps2fixer]

Can you post a video? It might help to identify the cause better.

[Atc 200x 1985]

Sure how would I do that do I copy the link of the video? Another thing is it still hard starts but I have to put fuel in the spark plug hole then it would start.

[ps2fixer]

Yea, just copying the url of the video and pasting here would be good enough for us to see it. Youtube, facebook, etc should work for uploading, just make sure the video is marked for public view.

[MrConcdid]

What did you do to make it start again?

[yaegerb]

no Boring or honing was done when I installed the new piston. should I have honed it? Sorry I should’ve made that clearer.

Yes, you always bore and hone a cykinder when installing a new piston.

[Atc 200x 1985]

is It too late for me to take it apart and hone it or have I caused damage I haven’t ran it for very long after I put the piston in. Also here is the video of what is going on with hard starting
https://youtu.be/MiPWC9Yn2oY mind all the junk In the background I haven’t had time to clean my shop.

[ps2fixer]

In the video, sounds like you have pretty good compression (effort for kicking it). A new piston should have a hone done on the cylinder before installing, this helps the rings break into the cylinder walls.

The timing doesn't sound wildly off to me, the way it starts/runs seems to be more of a carb/fuel mix related problem. At startup, it almost acts like it's out of time though, but once running it doesn't seem too bad. Probably wouldn't hurt to do a plug check and see what it's showing. I'm far from a carb expert, but it seems the main jet is too lean and the pilot needs adjustment for easier starting. It sounds a bit like it's loaded up at idle, as in too rich which should mean the plug is turning black at idle if I'm correct.

Carb adjustments can always be reversed, count the turns in for the pilot jet till you get resistance to get your base line number so you can always go back and try to turn it in 1/4 to 1/2 turns in and see if it makes any difference on idle/starting. Shouldn't be any throttle needed to start the engine when tuned correctly.

Instead of trying to describe the whole process of the trial/error style tuning, here's a section of a book on how to do it. This is from Kawasaki for race dirt bikes, so there might be some 2 stroke only related things in this, but should be a good read for anyone new to carb tuning. This is in the context of a carb that's clean and doesn't have issues like plugged jets or passages.


https://i.gyazo.com/0a47fe91dcc9850f935dc1f6e099ab0b.jpg

https://i.gyazo.com/fdb71dcb1d4f0422de3e5ce7e5f83c04.jpg

https://i.gyazo.com/701e069f5e29d5b863a9440cfc3ae350.jpg

https://i.gyazo.com/09a145c06ef23a25e01061d3fcaa1de2.jpg

https://i.gyazo.com/5f6448c9e864cadffcf3e93bad176d15.jpg

https://i.gyazo.com/ff436348501afeda04632b293394d0bd.jpg

[Atc 200x 1985]

Yes I’m far from a expert too but normally I’m able to get it straightened out but this is real picky. Ill look at the spark plug and see if it is black. And I am with you on the fuel air mixture is what is causing the hard starting I’ll read this book thanks for it. The spark plug was black and wet.

[ps2fixer]

Black & wet, sounds like too rich to me.

I wonder if the carb is from another machine and the 200x carb jetting in the wrong carb is causing the unexpected overly rich condition.

Stock should be PD62B and has a bore size of 24mm, and a random example of a carb that might get mixed up on it could be something like the ATC200ES carb, PD55A and bore size 22mm.

I've created a table of carb ID numbers and what machines they go to. Far from being perfect, but gets atleast an idea what the carb is from if it's not stock.

https://atvmanual.com/honda/atv-oem-carburetor-throttle-body-identification

[yaegerb]

is It too late for me to take it apart and hone it or have I caused damage I haven’t ran it for very long after I put the piston in. Also here is the video of what is going on with hard starting
https://youtu.be/MiPWC9Yn2oY mind all the junk In the background I haven’t had time to clean my shop.

Yes, you should pull your cylinder and get it bored and honed to the next size piston. I don’t know what kind of budget you are on but LA sleeve can do the whole thing plus supply the piston for less than 200.00.

Also, your carburetor needs to be rebuilt, it’s toast.

[Atc 200x 1985]

yaegerb Yeah I am short on money rn but my grandpa has a honer could I just hone it or do I have to bore and hone it. I spent 200 bucks on that wiseco piston rings and gasket set. I bought a brand new carb and got new jets and everything it is one of those Chinese ones off amazon. Ps2fixer I bought that Chinese aftermarket carb off amazon they look identical to the original carburetor. I have the stock jet sizes 108 main, 40 pilot, and the 3 groove on the needle. Should I downsize the main or something else?

[ps2fixer]

Do you have a way to measure the China carb? Would be interesting to know if it's the same size bore or not. I haven't had much for experience with them, but the couple times I've been around them, they have been jetting wrong even though in both cases the engines ran "ok". With enough time, effort, and jets on hand, I would think you could jet it where it will run well, but it's a lot of trial and error, might not be the best route to take though.

What happened to the OEM carb, or was it missing? If you have it yet, could clean it up well, make sure no passages are blocked and swap the good Jets over to that carb body and probably have good results.


Yaegerb can confirm or correct me on this, but the hone/bore of the cylinder should be measured in several locations to make sure it's still squared up and the bore is round yet. If it's in spec, a hone is enough to give the new rings a fresh surface to break into as long as there isn't scoring in the cylinder walls. If it's beyond spec, then a bore is needed to size up the cylinder and a different piston size is required with another set of rings too. Also the piston should be measured for bore vs piston clearance spec and generally a machine shop will need the piston on hand before a bore job so they can bore to the actual piston size instead of what it's sold as. I think that covers the basics on the proper cylinder part, there's always the head, cam, rod/crank bearings etc to check. A full rebuild would include checking the transmission out and such too.

I proper build can get expensive really fast, but you know what you have. I've also seen people get away with doing things as incorrectly as possible and still ending with a reliable engine. Like my dad's 1953 Case Tractor engine build process was so much different than the correct route because of lack of parts, lack of money, engine design, etc. He grew up with his dad (my grandpa) being extremely tight on money and wouldn't spend any extra for some things that were really needed. Like gaskets, here's some gasket paper, make your own. Got a metal part that broke, weld it back together. This thinking/logic doesn't always work out well though either. My grandpa also had a T6 bulldozer that had a gear break back in like the 70's. It got tore down found the problem, and none of his kids would weld it back together and reassemble with the broken gear. It sat around till around 2008 when it got hauled in for scrap after he passed away because everything on it was pretty shot by then. Found out it weighed around 6 tons, probably what the T6 stands for.

[Atc 200x 1985]

Sure I can measure it I have a Venere Caliper I’ll measure it tomorrow or when I can. When I had it apart there were no major scratches but there was some but they weren’t bad at all like you would have to look at the cylinder a certain angle and you could see them it’s no hassle for me to pull the motor and hone it wich I am probably going to do. I’m not new to engine building but I ain’t no expert by any means. I’ll get that honer tomorrow and work on it. I measured and it was in spec that’s why I thought I didn’t have to hone. And I don’t have jets laying around but I can buy a pack of them off line that has all kinds of sizes for like 15-20 dollars. I have the oem carburetor but I switched to the China one I have the oem one I’ll put it back on when I can.

[ps2fixer]

Make sure the Jets are the brand name ones, no off brand ones. The other brands do not line up with the stock ones, so you'd be starting effectively blind with an aftermarket jet kit. Pretty much the numbers just tell you if it's bigger or smaller, besides that they don't really correlate too well from what I've read (no personal experience, I've always bought the name brand).

Your carb used Keihin branded jets stock, if you can get that brand with several jets for $15-20, shoot me a link, I wouldn't mind having a wide range of jets on hand. I paid like $15 for two jets off jetsrus with shipping etc.

[Atc 200x 1985]

Yeah the jet I have in there is some aftermarket rebuild kit but the pilot is oem Honda I’ll get you a link to them jets. What do you want a little of every thing? also another thing is do you want the long style of main jets or the short style? Just lemmie know.

[ps2fixer]

These would be the main jets I'd be interested in. ATC250ES/SX 350x style carbs.

https://www.jetsrus.com/a_jet_kit_atv/honda_350_ATC350X.htm

[yaegerb]

yaegerb Yeah I am short on money rn but my grandpa has a honer could I just hone it or do I have to bore and hone it. I spent 200 bucks on that wiseco piston rings and gasket set. I bought a brand new carb and got new jets and everything it is one of those Chinese ones off amazon. Ps2fixer I bought that Chinese aftermarket carb off amazon they look identical to the original carburetor. I have the stock jet sizes 108 main, 40 pilot, and the 3 groove on the needle. Should I downsize the main or something else?

Bore is likely out of round depending on the amount of hours since last rebuild. Only way to be sure is measure that is with a dial bore gauge. If it’s not within spec in the manual then yes you need a bore and then a hone.

Do you have the original carb? Never buy the Chinese ones. More headache than they are worth.

[Atc 200x 1985]

It has less then a hour since I put that new piston in yes I do have the original carb I will put that back on. Or are you talking about the previous rebuild cause if so it’s never been rebuilt until I done the top end.

[Atc 200x 1985]

Here is that link https://www.keihincarburetor.com/ this is where I’ve always ordered jets.

[ps2fixer]

That website is weird. They use the Chinese style listing "for Keihin" instead of saying it is Keihin branded jets aka it's likely generic/aftermarket, no mention of them being the correct brand, yet the photos show jets with the Keihin logo on them. I hate products that are listed so poorly. If they are not genuine Keihin jets, then they could likely get in trouble for using images that misrepresent the product.

Actually, just noticed, that site doesn't sell anything, they are just an affiliate link site, so they find products on Amazon and affiliate link them. Anyway, the listings aren't clear if they are the correct jets or not, so I'll take a pass on them.

Just wondering, for the extra jets, do they have the Keihin logo on them (the K that looks a bit like a star)? Here's a page that shows the logo fairly well.

https://www.jetsrus.com/FAQs/FAQ_identify_that_jet.htm

[Atc 200x 1985]

My pilot jet has the k40 but not my main jet so that would mean size 40 and some of the Showed the k on them but not all of them that’s why I thought that they were a good aftermarket seller. Some of those knock off brands can be pretty good.

[yaegerb]

It has less then a hour since I put that new piston in yes I do have the original carb I will put that back on. Or are you talking about the previous rebuild cause if so it’s never been rebuilt until I done the top end.

Send me the oem carb for a rebuild if you want. Send me a pm if interested.

[ps2fixer]

Yea, knock off brands *can* be good, but you have to discover which one is good. Pretty hard for them to machine the jets exactly the same as the name brand ones, so the jetting numbers can get close, but probably never be right. It's find to use aftermarket if you don't mind swapping the jets out to find the range it works and grabbing the middle one and fine tuning.

Kind of the same story as the China carbs, the machining on them will be sub par vs OEM, but in theory the stock jetting should be close to being correct if it's effectively a 1:1 clone.

Having yaegerb rebuild the oem carb isn't a bad idea either, I know he knows carbs better than me =).

[Atc 200x 1985]

I’m pretty good with carbs but not the best lol. I’m going to go back to the stock carb what jet should I go to I 105 I have a original jet made by Kehin 108 jet. I’ll think about sending it to yaegerb.

[ps2fixer]

If the machine is more or less stock, the stock jets should work and be about right. I'm not 100% sure what the effect of running a high compression piston would do with jetting with all else being the same. More suction per stroke might mean the jetting needs to be adjusted. Defo an area I don't know much about.

[yaegerb]

I’m pretty good with carbs but not the best lol. I’m going to go back to the stock carb what jet should I go to I 105 I have a original jet made by Kehin 108 jet. I’ll think about sending it to yaegerb.

The jets won’t help you. The oem carb needs to be completely taken apart, cleaned and put together with a rebuild kit. I have done many carbs and the vm24 is no exception.

[Atc 200x 1985]

what I’ve read is when you up your compression normally it doesn't suck in more air because you haven’t changed how long the intake valve is held open. But I could be wrong I’ll go and clean the oem carb and rebuild it soon.

[ps2fixer]

Because the compression ratio increase, the piston all the way to top dead center has less air space vs bottom dead center which creates a higher psi when doing a compression test, and in my mind should suck slightly more air, but you might be right on that. That's a weird thing to think about, I guess it makes sense why HP doesn't really go up with high compression only, valve size, how they breath, porting, exhaust, etc has to change to get the high hp numbers. The higher psi creates more torque, so the speed it revs up should stay pretty similar. Never quite thought about it like that before, pretty neat mind exercise.


@yaegerb, what's the vm24 in reference to?

[Atc 200x 1985]

Another reason why I don’t use the oem carb is because all the holes are stripped out forgot to tell y’all and it got put in something and left out side for like 5 months. I need to get some bigger screws to put in there.

[Atc 200x 1985]

I forget to tell yall that plastic thing that goes on the main jet I do not have could that be my problem?

[ps2fixer]

I've ran a few machines with that part missing and didn't cause a noticeable issue on flat ground or starting. I think it's a bit like a baffle in a car tank to keep the jet always supplied with fuel even in rough riding, hills, wheelies, etc.

[Atc 200x 1985]

Ok. And I believe that is what it is for.

[Atc 200x 1985]

Do yall think It could be out of time? I know that carburetor needs tuning but it should start atleast even if its out of tune.

[Atc 200x 1985]

Another thing I was thinking about is does the 200x’s have a de compression system?

[Maynard James]

Another thing I was thinking about is does the 200x’s have a de compression system?

Yes it does.

[Maynard James]

The very first thing anyone in this thread should have recommended after reading your first two posts is a compression test. Im not reading it all. Have you done one?

[Maynard James]

Yes it does.

Wait no it doesnt. My mistake. Been a long time. You can put the 200s decomp on it of you use the cam.

[Atc 200x 1985]

Ok. Cause when I had the engine apart for a rebuild I didn't see any signs of a decomp system. the compression is with the slide on the carb closed maxes out around 88-90 psi, with the slide open as it says in the manual how to do it maxes out around 180 cause of that new piston. before even with the slide open would max out around 100-125 I can't remember exactly on that but it was around there. And with the slide closed with the old piston was around 35-40 so a noticeable difference I would say because of that new piston.

[Maynard James]

Always check compression with the carb open. Intresting to see data from both, though.

Yeah im almost sure there is no decomp connected to the kicker on them but Ibe taken some hard hits over the last few years and dont have time to check rn. Open to being corrected but im pretty sure ive had plenty.kickbacks froma 200x because they dont have decomp.

Shlt. Ima have to read it all now.

Im not being arrogant but these are VERY simple engines if they are mechanicall correct after the build. Try not to overlook anytjing. Ive made the mistake also on hyperfocusing on certain parts because thats what it should be. 180 is good compression, sounds fine for a new rebuild. Ill read the whole tjing now and see if I can offer anytjing solid.

[Maynard James]

Lotta dart throwing going on here.

You dint build it right, so now I cant trust your test specs either.

If you come onto a forum amd ask why tjings arent running right, then reveal that you didnt build it right. The thread should end there. You need to measure your bore in 6 places, order a new piston, new rings, new valves, and start over. When the piston shows up, have the cylinder bored and honed. You absolutely cannot just throw a piston and rings in a worn bore and hope it runs right.

Do it right or don't do it. You are wasting your time and everyone elses by denying the obvious.

[Maynard James]

P.S.

Yes, increasing compression only, does absolutely raise the power of every single internal combustion engine. It is an air pump. More pressure means more power, period. No exceptions. Umtil it blows up.

[Atc 200x 1985]

I measured the bore in 6 places I followed my manual and the manual that came with the piston they were all in spec that is why I thought I didn’t have to hone it I should’ve honed it but I didn’t it’s a simple mistake And the bore didn’t even look bad it looked fine. I am not new but not a expert to the engine building I have built other engines before but my manual didn’t say anything about getting new valves in it anywhere. Couldn't I just get it bored and then sleeved to the same size so I don’t have to blow 250+ dollars on a new piston, rings, gasket set, and valves? The piston should be fine it didn’t even run for very long when I put the new piston in. Thanks for the info I really don’t want to go and blow another 250+ dollars cause I don’t have that kind of money I know people that own a machine shop I’ll pull the bore again tomorrow and get In touch with them and see what they can do. Or are you talking about getting the next size up piston or boring it and then sleeving it like I am talking about? I am totally fine with getting new valves they are only like 50 bucks but I really don’t want to buy a new piston, rings, and gasket set with that. I did everything the manual said expect for the honing part cause I skipped over it by accident. If a piston is absolutely needed I could probably get them to make me a billet piston and heck even a new billet cylinder if it’s needed.

[Atc 200x 1985]

Also yes they are very simple engines every other one of these kinds of engine I have worked on would always start with something wrong with them but this one it would never run even if something was off half a turn and it shouldn’t be like that. I forgot to put in that I measured it in 6 places sorry. I have overlooked and hyperfocused on to many things with that engine over the past years I have been working on it. I was trying to take the easy route and not tear the engine apart but then I got some help with it and I finally broke down and tore it apart and what do you know the rings are bad cause there is oil on top of the piston. But I guess I overlooked the engine build too and rushed it and screwed it up too. :/

[ps2fixer]

Since you know people that own a machine shop, before you drop a bunch of money on parts, I'd ask them their opinion on the bore/hone situation and see what they say. Yea the cylinder should have been honed, but that's to ensure the new rings seat to the cylinder the best as possible. If you wanted to undo that, in my book, new set of rings and hone it and it would be good, maybe even just hone it and reuse the rings. I'm no expert on engine building, so I'll leave it to the guys you know that does it every day to give solid advice on. Personally if it was me and my machine (not going to be sold etc), I'd run it as is, it's pretty hard to mess up a compression test and get a higher than expected reading, only the lower than expected reading, as stated, throttle should be wide open when testing.

The stock spec for your engine is 164psi, so you getting 180psi suggests the higher compression piston is at effect and the rings are seating well. I haven't checked the manual, but you might want to check for a break in procedure too. If there isn't one, I have a Kawasaki race prep and tuning manual that has a section on that topic.

Also, no decompression system that I see in the diagram. If there was one, it would be near the cam and it opens the exhaust valve if I recall correctly. Lever is activated by cable (like atc350x) or lever (like atc200es).

https://www.partzilla.com/catalog/honda/atv/1985/atc200x-a/cylinder-head

[Atc 200x 1985]

I know it should’ve been honed but I forgot about it I was way to excited to get that piston in there. One this is I put it in wrong it ran somehow with the piston in wrong but not right at all. So I pulled the engine and flipped the piston it was still in excellent condition. I may go with your advice new rings and a hone just because I’m short on money right now. If I had more money I would go and buy a new piston, rings, etc and just use that piston and buy some new rings and a gasket set for it in a 200s that is going to need a rebuild soon. Which manual are we talking about the one that came with the piston or the climber manual? And I have no idea how you would get a higher compression without it being built correctly all I’ve heard of is getting lower. I’ll get in touch with them today I may bore, hone, and sleeve it just in case ;).

[ps2fixer]

Not a fan of the 3rd party manuals, the Honda made manuals are free online. They seem to be less wordy and are more focused on specs and raw tech talk type of stuff, so might be a bit of a learning curve to get used to it.

http://www.oscarmayer.net/atc/manuals/

Pretty interesting that the Honda manual doesn't mention anything about honing or boring, just check the specs, if in specs it's good basically. Might be one of those things that it's targeted for techs to use, not the general public, so they don't spell out every step fully, they are just trying to provide the basic process and tech data to shops that need it.

[Atc 200x 1985]

I didn’t realize Honda made manuals for those online. I have looked before but I could never find the correct one or one that the website didn’t require you to download it. Now the climber manuals are one that all the pros use their more focused on performance but they do have stock stuff in there. One thing I like about them is they have a full wiring digram in color so that’s real helpful but the Honda manual is real neat it gives you a flow chart of what’s going on. Not saying the climber manual is bad but it doesn’t really tell you what you can do to fix the problem like there is a chapter in it for troubleshooting but it just asks you what is happening and you narrow it down. Update on the three wheeler I don’t know what happened but the ignition coil just lost almost all of its secondary values the primary are still fine but not the secondary. Do you have a link to a good ignition coil? I think what happened was I was trying to start it and didn’t put the plug wire back on and I think that probably messed it up.

[ps2fixer]

Ignition coils are quite robust, you could have a spark plug wire issue though. I'm pretty sure your machine uses an ignition coil with a replacable spark plug wire and spark plug cap. Well instead of saying I think, should just look it up...

https://www.partzilla.com/catalog/honda/atv/1985/atc200x-a/wire-harness

Yep spark plug cap comes off. Sometimes you can unscrew the spark plug cap, nip off a 1/4in or so of the spark plug wire, put the cap back on and get good connection. Also it doesn't hurt to test the spark plug cap, screw to the spot the spark plug clips into (make sure you're hitting the metal on both sides with the probes). Reading should be around 5,000 (or 5k) ohms. You can also test the secondary coil in the ignition coil ground to the hole in the wire, that should give the reading that the service manual states (sometimes they have a value with and without cap).

Ignition coils can fail in different ways, so not saying yours is good, but a lost connection doesn't always mean it's junk either. Generally a wire breaks internally (no connection ever), or the wires start to short out together internally (lower than expected ohm readings), but heat can cause the issue to change or physical movement. This is why an intermittent issue is sometimes hard to track down on the electronics side of things (a lot of parts use a coil in some way).

I've never heard of an ignition coil going bad because the spark plug wire wasn't hooked up, I doubt that's the cause of the no connection issue.



Not trying to bash the other brands of manuals, but I go over the Honda manuals all the time to post public specs. It's simple data that Honda has published, and I've found a fair few mistakes in the 3rd party manuals. Honda isn't perfect either, I've found plenty of mistakes there too. Color wire diagrams are nice, but you can go cross eye'ed trying to look at some of the colors when they are bright and there's a million striped wires, I actually prefer the black wires or solid colors that label the strip at wire ends. Also it's worth noting, the wire diagrams can be very generic and things might not match up on the physical harness. One diagram doesn't cover a whole model unless the harness didn't change which is pretty uncommon, but the atc350x is an example. Like the ATC200/ATC185S harnesses changed every single year, so a diagram for each year should be in the book even if the change is minor.

Here's an example of the style of wire diagram I like, I built it so clearly it's my preference lol. I also make sure to label everything including colors for those that are color blind, or you have two similar colors and they are not clearly defined what the difference is on the diagram.

https://atvmanual.com/honda/atc110/1985-atc110-wire-diagram

I've been trying to "modernize" the wire diagrams too, which right now isn't live, but I want to make the wire diagrams interactive. Like in my diagram above, it focuses on showing the physical layout pretty well, the harness tubing is shown so it can make slightly more sense. I'd like to set it up so it's fully interactive. Like you click on the ignition coil and the ignition circuit wiring high lights, the ignition coil "pin out" shows up saying which wire has what function, and also trouble shooing data such as the primary and secondary ohm specs which I plan to add a link to that for the "how to" do it, images and everything. Tons of work on my end, but I envision it should be really nice for both the person at home doing this stuff for the first time, and the professional that just needs the service data, pin outs, what wire goes were type of data.

Just blurting ideas out, but I think it would be really neat to simulate issues within the wire diagram since it's already interactive. Like let the user "break" a wire and see what issues pop up at each part. Like if you break the black/yellow wire at the CDI box, the only issue you'd see is the ignition coil not receiving power, spark plug gives no spark. Could add in things like components going bad like the exciter coil and set to either internally shorting (lower ohms than normal), or broken coil wire. Ideally links to how to test for each problem.

Anyway, not trying to turn this into an advertisement for my site even though it kind of did in a round about way. I haven't used the other brand manuals much, only thing I've noticed is they are more wordy, like they are trying to teach you how to do the job while the Honda manual is more tech info only, so more focused on professionals. Having any wire diagram is clearly better than none. I'm able to trouble shoot a lot of issues just by looking at a wire diagram. I'm wide open on feed back for my diagrams too, good or bad. I know the symbols aren't the most amazing, my graphic skills aren't anything special. I base them on the physical harness in hand and the Honda wire diagrams from the related service manual. I'm human, so it's possible I've made mistakes, but I can fix them online, little hard to fix a diagram in books.

Also, I should mention, those Honda manuals are not given freely by Honda. Effectively someone scanned a physical manual into a PDF, and several people volunteer to host them for free. They could get a DMCA notice at any time and the manual links would go away (or face possible court). Thankfully Honda hasn't gone after anyone that's hosting manuals yet. In my opinion having tech and service data publicly makes it more likely for people to use their products since parts and data are two critical things needed to keep a machine working even if new. The concept of my site is to recreate what I can as an online free manual that has no copyright issues. Trying to keep the advertising down so it's not annoying to use, and make it user friendly. The project is nothing but a big loss right now, not really worried about that short term.

[Atc 200x 1985]

In surprised it went bad now. It was just one of those cheap ones off amazon. I know it’s not the plug wire because I measure with a different one and the one that came with it. That’s gonna be pretty cool once you get all those features on to your website it’s really gonna help people out I would say for people who don’t have a book manual I know your not trying to turn it into a ad for your website but you gotta promote it somehow or you won’t get visitors. Yeah that climber manual is wordy one really for Techs but that Honda manual is focused on specs. With the spark plug wire unhooked it will produce the highest voltage since there is no way to regulate the voltage. That is the spark plug Job is to regulate it and channel it on to the electrode and create a spark. With that climber manual there was a a few mistakes that I noticed one of them was the polit screw was 2-1/4 but on the Honda manual it was 1-1/2. I’ll I’ve found me a new ignition coil it’s a actual name brand one and a oem replacement.