//ArrowChat Code
Page 1 of 3 1 2 3 LastLast
Results 1 to 15 of 45

Thread: China CDI Reviews on ATC350X

  1. #1
    Join Date
    Apr 2012
    Location
    USA
    --
    4,114

    China CDI Reviews on ATC350X

    Well I've been poking around China CDI's a bit and figured I'd find my findings, atleast for using them on an ATC350X.



    First thing first, they are all wired based on the 350x pin out, so it's a nice stright plug in and test vs stock. My stock CDI works great, so I can do ABA testing. These reviews are purely based on listening to my engine and basically dry reving it. The stock CDI revs out the full rpm range well, but I do know the top end is a bit on the lean side (need to rejet for the DG exhaust I put on it).


    Click image for larger version. 

Name:	IMG_20181212_151310_079.jpg 
Views:	27 
Size:	696.9 KB 
ID:	256120Click image for larger version. 

Name:	IMG_20181212_151655_303.jpg 
Views:	26 
Size:	1.02 MB 
ID:	256121
    First one up is the most expensive China CDI I bought a "Racing CDI", still stupid cheap compared to even used CDI's. This fancy blue housing CDI looks to be built fairly well. The red LED light blinks per spark, after a little bit of RPM it appears to be solid on, probably just blinking faster than my eyes can see. It started the engine and idled well. Low to mid range it ran just like stock. Had high hopes, but high rpm it doesn't rev out fully. I suspect the timing is too far off from what the 350x engine demands. If you never get above around 3/4 throttle, this CDI could be a cheap alternative if you're in a pinch. China part number on this one is H048-014.

    Click image for larger version. 

Name:	IMG_20181212_151348_617.jpg 
Views:	23 
Size:	715.3 KB 
ID:	256122
    Second CDI is this ornage housing one. I've read people were having luck with them working out well. The China part number on them is H048-016. This one ran the same as the above CDI for idle and mid range. The high rpm was even worse though, not a huge difference but probably 500-1000 less rpm (I need to get a tach to be more scientific lol).


    Both of the above CDI's made the high rpm sound like it was leaner than the stock CDI, maybe it's just from a stronger spark and retuning would fix the problem? I'll have the CDI's around when I rejet the engine some day.


    Click image for larger version. 

Name:	IMG_20181212_151443_506.jpg 
Views:	24 
Size:	669.6 KB 
ID:	256123
    The last CDI is the typical black one that looks similar to the stock one. Looks exactly the same as the orange one, but the plastic housing is black and the epoxy fill was done horribly (not flat at all). This one wouldn't fire up the engine. I gave it a little gas and it puffed a nice ball of smoke out of the carb. I guess this is a 2 stroke CDI or something. The China part number for this one is H048-024.

    Click image for larger version. 

Name:	IMG_20181212_151545_266.jpg 
Views:	22 
Size:	872.8 KB 
ID:	256124
    Bonus CDI, in the past I bought this one with high hopes, but like the ones above, it falled short. It was hard starting, but I could get it going with a little throttle. It advanced the timing WAY too fast, at around 2500-3000 rpm it would hit a wall and not rev any higher. I don't have the part number for this one sadly. It's slightly smaller than the above one though.


    Click image for larger version. 

Name:	IMG_20181217_155413_220.jpg 
Views:	10 
Size:	729.8 KB 
ID:	256185
    Bonus #2!

    Stock 1999-2004 TRX400EX CDI part number 30410-HN1-003. One of the replies to this thread suggested this was a suitable replacement. The 400ex is just a tiny bit smaller than the 350x CDI, I can get measurements if someone needs/wants them. I warmed up the engine with the stock CDI again, double checked it revs out well and all is good and smooth. Popped on the 400ex CDI (service manual calls it a ICM [Ignition Control Module] btw) and it fired up exactly like OEM. Low to mid range seems to be a perfect match. However once again, top end it's not quite right. I had a couple back fires though the exhaust, nice flame effect but not running perfect. I'm wondering if it's hitting a rev limiter or something. So once again stock OEM seems to be the thing to stick to.



    Mikes ATV Fix CDI

    Took me forever to get my carb cleaned, reassembled and reinstalled, but I'm back at it again. My machine is an 85 350x with what we suspect is the "low voltage" stator design, so we pretty much expected there to be running issues since other's have had issues too. From my understanding the 86 stator's exciter coil puts out more power and runs this CDI just fine but I don't have the newer stator on hand to test the theory out. Anyway, as normal, fired up the 350x and warmed it up with the stock one to make sure all is running fine, carb is a lot better now that it's been though an ultra sonic cleaner. It's a tiny bit lean so likely need to raise the main jet a little, but it's pretty close to being right. I popped on Mike's CDI and tested the "easy start" feature which seems to work well, I can hear the timing change after the first fire, just took enough rpm to get a spark. Stock takes a tiny bit more rpm, but not much more when warm at least. Low to mid rpm sounded the same as stock, however high rpm it seems to hit a wall like spark just dies right out, almost like a rev limiter but it doesn't fire at all till I let off the throttle. If I bring the RPM up very slowly I can get it almost as high as stock before it starts to break up.



    I built myself a special adapter so I can tap into the CDI wires while it's running to take readings. This test isn't standardized at all, but might show a bit of what's going on. Probably best to take this section with a grain of salt since it's only one metric to base things on. The idea is I can use my home built peak voltage tester to take a reading of the input voltage from the exciter coil and compare to the output voltage to see how efficent the CDI is at passing though voltage. Amps/current is the other half of this and I'm not sure how to read that matric with this kind of setup. I performed the test at idle, but the idle was a bit high, roughly 1600-1800rpm.

    Anyway, base line reading with the stock CDI was as follows:
    Exciter (CDI input power) - 207v
    Ignition Coil wire (CDI output power) - 92v
    Note: Output voltage increased with higher rpm till higher rpm then it dropped a little. Not going to red line my engine long enough to get actual numbers though.

    Mike's CDI tested as follows:
    Exciter (CDI input power) - 76v
    Ignition Coil wire (CDI output power) - 29v
    Note: Output voltage dropped with more rpm

    Orange CDI from above:
    Exciter (CDI input power) - 79v
    Ignition Coil wire (CDI output power) - 29v
    Note: Output voltage dropped with more rpm

    I think the next step is to buy an ignition test light and check what the spark curve looks like for each CDI that makes the engine run at least ok.
    Last edited by ps2fixer; 07-07-2019 at 04:56 PM.

  2. #2
    Join Date
    Aug 2005
    Location
    CT
    --
    206
    Thanks so much for testing these. I have a 400EX CDI on my 350X and it plugs right in and works great. They're way more common than the 350X ones. I'm curious how it would have fared in your test.

  3. #3
    Join Date
    Apr 2012
    Location
    USA
    --
    4,114
    My test is nothing special, but I've grown up working on engines and such so have a bit of an ear for if it's running right or not.

    I've pulled timing spec numbers from a bunch of service manuals, but I think the 400ex (and a lot of newer machines) don't list hard numbers for timing specs sadly. If you have a timing light, you can see if the timing is within the range it should be. There's two screw caps on the side of the engine, the top one is to see the timing mark. There's generally an "F" mark for idle fire timing, and two lines that show full advanced timing. I don't have a timing light right now, but I'd like to run though the CDI's again to see just how far off they are.

    From my little bit of poking around, it seems the idle/low end timing is fairly consistant between 4 stroke engines, but the high rpm it changes a fair bit. Newer engines seem to advance more aggressively, and sometimes have a bit higher stock idle timing advance too (might be mechanical based though).

    Anyway, if someone wants to send me a 400ex CDI, I'd try it out and see if I notice any difference. I suspect it might advance a tiny bit too much, but probably not a deal breaker. I'd think more advancement would be ideal for a built engine though.

    I've heard some people having problems kick starting their 350x, mine starts generally first or second kit, but my compression release cable is adjusted spot on, I don't even feel any compression while kicking, just feels like I'm kicking it over with no spark plug in. My other 350x feels like you're hitting a wall on the compression stroke lol, it's decompression cam/shaft is broken so it doesn't work at all.

  4. #4
    Ranvier is offline At The Back Of The Pack Arm chair racerAt the back of the pack
    Join Date
    Sep 2016
    Location
    Phoenix, AZ
    --
    307
    Great work. It would be awesome if someone had a ricks cdi in addition to the 400ex and oscars to test.

    As far as hard starting, I am curious if a grounded plug would have a visually stronger or better spark?

    If you find one that does seem to rev ok at higher rpm, a test under load would be useful.

    Thanks again for taking the time to do this and write it up.

  5. #5
    Join Date
    Aug 2008
    Location
    devore,ca
    --
    1,015
    People that have a hard time starting their 350x just aren't going through the starting sequence right. It has nothing to do with spark. I struggled with mine for years until someone (vegas 250rr) showed me how to do it right. You have to get the piston just past tdc on the compression stroke before you kick it or your just wasting your time. I have one 350x with a high compression piston that has a broken decomp system and it still starts easy.
    YAMAHA 450 HYBRID
    85 350X- RED
    85 350x -BLACK
    86 350x-WHITE (with Goki)
    85 250r
    83 atc 70
    84 atc 70
    84 atc 110
    09 yfz 450
    2006 Arctic Cat Prowler
    RZR XP 900

  6. #6
    Join Date
    Apr 2012
    Location
    USA
    --
    4,114
    Quote Originally Posted by Ranvier View Post
    Great work. It would be awesome if someone had a ricks cdi in addition to the 400ex and oscars to test.

    As far as hard starting, I am curious if a grounded plug would have a visually stronger or better spark?

    If you find one that does seem to rev ok at higher rpm, a test under load would be useful.

    Thanks again for taking the time to do this and write it up.
    Oscar said he was going to send me one for my 350x. Once I get it I'll test it out.

    I ebay'ed for a 400ex CDI, and dang there's a flood of China CDI's everywhere there. Sorted by used only and cheapest first, and like the 3rd listing was a CDI + regulator/rectifier. Never hurts to have more parts on hand so went for them at $10.45 shipped on both. The listing says the parts came from a 2004 TRX400EX (CDI part number is 99-04). $10 for a back up known working CDI is cheap assuming the 350x runs good with it. Also Honda still makes them, but they do cost more than Oscar's CDI's which would be mapped properly for the engine and possibly has more modern tech in them.

    https://www.partzilla.com/product/ho...d632f9b6ad7bef

    Yea a load test would be doable, my tank is screwed up atm, have to fix it, and one of my foot peg bolts are broken off. It's cold here so I'm a little bit lazy on the working outside in the cold lol. I'm using a dirt bike tanks currently, doesn't exactly fit the machine right lol.

    Out in the open air spark doesn't mean a whole lot. It's a good way to see a very week ignition system, but strong vs stronger it makes no sense. My dad has a spark tester for Chain saws, basically it runs inline with the spark plug, you set the gap to a min spec and start the engine. Then you widen the gap till the engine dies. This test basically tests how much voltage (spark distance) the machine has. The chainsaws my dad works on can get somewhere around 1/2 an inch or so gap + the spark plug on OEM coils. I doubt I could get a good photo of the process, but I suspect I could borrow the tool some day. Would tell me if my coil is healthy and the CDI/Pulse generator are working well. I believe my while stator assembly is more or less new, the guy I bought the engine from bought one of those NOS engines likely from ebay for his machine and I think he swapped the stator assemblies because of the cut wires. That was one of my first tasks after owning the harness making tools. I'm also thinking about getting some sort of tach, atleast for testing things, setting idle etc. Would be interesting to see what my engine's max rpm is. If I recall correctly Oscar said the 350x stock CDI has a 9k rpm rev limiter. My dad also has a "wireless" digital tach that works really well on chainsaws. I've seen it peak out around 14,800rpm when the engine went super lean, seems like the carb isn't getting enough fuel flow and running out of gas. Piston is lightly scored as well so needs cleaned up too.


    Quote Originally Posted by BOB MARLIN View Post
    People that have a hard time starting their 350x just aren't going through the starting sequence right. It has nothing to do with spark. I struggled with mine for years until someone (vegas 250rr) showed me how to do it right. You have to get the piston just past tdc on the compression stroke before you kick it or your just wasting your time. I have one 350x with a high compression piston that has a broken decomp system and it still starts easy.
    If the decompression release cable is bad/worn/not adjusted right, or the cam shaft that goes in the head is worn/broken, then yes you must get just past the compression stroke and kick it. My beater/ugly 350x has it working, I can't even tell where the compression stroke is, I just kick it and it fires up. My other machine's decompression shaft is messed up so it doesn't work at all, so I have to get past the compression stroke and kick. It's a lot more effort to start, but it generally starts in 1-2 kicks as well. I'm more of a computer tech guy, so maybe my leg is just weak, but I much more prefer the compression release working right machine and the nicer one I have I plan to replace the bad parts on it so it's like it's brother. If my internet wasn't crap, I'd get my 18 year old sister to start each machine, I'm sure she could start the one with decompression release working, the other even with the right technique she probably couldn't start it (she's skinny as a bean pole).

    I'm not sure if any work has been done to either 350x engine, but the one with decompression not working, I can nearly stand in the kick starter on compression stroke and not turn the engine over. I'm around 150lbs or so. My ankle hurts if the engine gives me fits. My last ride with it was out in state land, and the carb decided to flood on me out of the blue. Had fun turning the gas on, waiting for gas to pour out, then turn it off and ride and try to fiddle with the gas valve to keep it going to get back to the truck.

    The process of getting just past compression stroke is pretty typical for with higher compression. Most of the time I ignore it on my 250es/sx since they are easy enough to start. Never checked if they have a decompression system, but the compression stroke doesn't feel like a wall you have to overcome.

  7. #7
    Ranvier is offline At The Back Of The Pack Arm chair racerAt the back of the pack
    Join Date
    Sep 2016
    Location
    Phoenix, AZ
    --
    307
    Haha at my sister can start your trike.

    So the healthy blue spark dogma is crap? It’s all or nothing? I learn alot from your electrical posts so thanks for taking the time.

    And agree with bob, the technique on the X makes all the difference.

  8. #8
    Join Date
    Apr 2012
    Location
    USA
    --
    4,114
    Yes and no for the blue spark thing. Orange/Red is 100% weak spark. Blue/White can be weak spark too, but it's likely to run on it in most situations. Make the engine too rich or lean and it might not run. High rpm could have issues etc. Think about it, open air spark is atmosphere pressure with minimum air movement, inside the cylinder it's like 200mph winds, and it's 150psi (over 10x more dense air). If you have 2 stroke, you also have oil in the air too. Of course there's fuel in the air too.

    It's always best to have the right tool for the job. This the exact tool my dad bought and it seems to work extremely well vs the ground the plug and check for spark method. It also gives a nice performance measurement. If something claims a stronger spark, this tool can measure if it's true and by how much. Pretty sure you can do the math and calculate what the voltage is based on the total gap. Anyway, it's a Oppama PET-4000.

    And here's a related video with a chainsaw that's no spark with great compression, good spark, and good fuel supply, this is the special case the tool is actually made for. I believe you can buy them either Echo brand on it or the "generic" Oppama. A quick google search looks like it's around $60-100.

    https://www.youtube.com/watch?v=dipmevU5cjU


    Also, the idea about my sister starting the 350x came from this video. My dad has one of the same series chain saws (4200, 43cc I think, professional series). We like Dolmar and Mikita chainsaws. I own a bunch of 6400 series (professional 64cc), and a 5100 series (51cc professional), this is the one with the carb issue I mentioned before. My dad also has a 7900 series and 9000 series (79cc and 90cc). Dolmar/Mikita model numbers just make sense, 2 number is home owner grade, 3 number is farm and ranch grade, and 4 number is professional. First 2 numbers are the engine size, or really close to it.

    This Dolmar 420 has the "easy start" system. It starts better with an adult pulling of course, but, she can get it to start lol. These saws have a bit of a process to start them, choke and pull till fire (max 3 pulls), take off choke and it will run, easy start or not. If you're not careful with the choke, it will flood, and it won't run on full choke most of the time. If you're good, you can pull it on full choke and have it fire and slap it off choke and have it going. Of course this is cold engines only, warmed up ones is just pull start it, if that doesn't work choke and unchoke it (sets a high idle).

    https://www.youtube.com/watch?v=s2Jv9I1jGkk
    Last edited by ps2fixer; 12-13-2018 at 01:26 PM.

  9. #9
    Join Date
    Aug 2008
    Location
    devore,ca
    --
    1,015
    I agree that having the decomp working properly makes life a bit easier on kicking, but almost all the ones I see aren't working right anyway or are flat out broken. I guess the point I was trying to make is people are asking if these CDI boxes are going to solve their starting problem or not. They will if your current CDI isn't working. But they won't if you just don't have the sequence down.

    A few years ago I bought an aftermarket CDI for my 250R that was supposed to produce a " hotter spark" from "Ricky Stator". It didn't make any difference in the way it started or ran. The spark plug looked the same after running also. I just carry it now for a back up.
    Last edited by BOB MARLIN; 12-13-2018 at 04:38 PM.
    YAMAHA 450 HYBRID
    85 350X- RED
    85 350x -BLACK
    86 350x-WHITE (with Goki)
    85 250r
    83 atc 70
    84 atc 70
    84 atc 110
    09 yfz 450
    2006 Arctic Cat Prowler
    RZR XP 900

  10. #10
    Join Date
    Apr 2012
    Location
    USA
    --
    4,114
    Yea, Oscar/Mike claims the same thing. I think the wording might be a byproduct of language translation, atleast in the case for Mike. He's working with a Japanese company that manufactures the actual product in Taiwan. Of my understanding, they use a larger power storage capacitor (something like 4x larger), so when it sends the signal to the coil, it's a stronger "hotter" source signal for the coil to use. The coil does the leg work of upping the voltage high enough to actually spark the spark plug. Just my theory, but I think a modern "hotter" CDI + a proper hotter coil would net a stronger spark (higher voltage). I suspect mis-matching the two parts would net you with near stock level performance in the spark department since a higher output coil would likely need more input power, and the high output CDI would just make the stock coil put out more amps, not more voltage, unless the signal voltage is higher.

    Of course I'm not an electrical engineer, but I do enjoy learning about electronics/physics.

    Now my interest is perked on if there's any disadvantages to a higher output coil/CDI, or what the real need is vs just saying it has better spark.


    Also, I agree, a CDI change isn't going to fix starting problems, Honda engines generally start easily, if not there's an issue. If the issue is the CDI, then replacing it clearly would fix it, otherwise, someone needs to get in there and diag the root problem.

  11. #11
    Join Date
    Apr 2012
    Location
    USA
    --
    4,114
    Looks like the folks with scooters are doing about the same thing I'm messing around with. The blue and orange CDI looks just like the ones above, probably the same manufacture, but there are different models that all look identical for the orange/black ones. I kind of wonder how he got the hard timing numbers with the timing light. My guess is looking at service manual specs (base timing + max advancement) and pixel measuring the video. That's the same test I wanted to perform myself with a timing light. I think these CDI's are actually designed for the moped/scooter engines, so it makes sense that their spark curves are very similar. To compare, the stock 350x timing notes in the Honda service manual says, base timing is 10 degress BTDC, and full advanced is 30. Sadly that doesn't give the extra timing info of the actual timing curve, but the graph in the video seems to graph it pretty well.

    Based on his graph, base timing is more advanced than stock 350x by a lot, just like his stock unit vs the China ones. The interesting thing is, they loose advancement as rpm increases, around 6-7k rpm it shows around 24-25 degrees advancement, vs the stock one which should be around 30. That explains why the high end seems off to my ears. It's kind of funny, all of the China parts that guy bought, and end of story was stock is still best. The pickup/exciter coil mod was something I had in mind, but I was basing the idea on what people do with chainsaws, they use a degree wheel, and advance the actual flywheel (no key installed) to achieve the advancement. In their case the pickup/coil/"cdi" is all one part so not too ideal to grind away at it lol. The pickup coils on the other hand are something like $20 new. I wonder if there's much of a performance gain advancing the timing with the stock coil on a more or less stock engine. Wish I had a dyno locally to get hard numbers.

    Also note the use-age of the large gap spark tester to give proof the China hot coil is junk =).

    https://www.youtube.com/watch?v=p63JXW29tVo


    Little more info that seems to make sense. The CDI doesn't actually advance the timing, it works in reverse, the pickup coil is at or near full advancement already, and the CDI delays the spark signal to get it's idle/low rpm timing and as it increases in rpm, it reduces the delay. In other words, if you want more advancement at max rpm, you have to physically change the pickup location, or make it get the signal sooner. That's not my direct goal, but figured it would be worth mentioning. There seems to be a lack of actual tech details about CDI's, ignition advancement and such with the searches I've used.

    So in theory, the China CDI's are just more or less a 5 degree delay and don't do a whole lot while the stock CDI is delaying the spark around 20 degrees. Makes sense why they are cheaply built, they do less than OEM. In that video, you can see how nicely the OEM unit works. Doubt there will be a cheap alternative (aka Chinese) that will duplicate that kind of results.
    Last edited by ps2fixer; 12-13-2018 at 08:19 PM.

  12. #12
    fabiodriven's Avatar
    fabiodriven is offline Aspiring romance novel cover model, and the Official 3WW slayer of thieves and swindlers. Catch me if you can
    Join Date
    Jun 2008
    Location
    The woods
    --
    10,515
    Quote Originally Posted by ps2fixer View Post

    Of course I'm not an electrical engineer,

    .
    I call BS on that.
    85 Tri-Zinger 60
    85 ATC250SX
    86 ATC250SX
    87 ATC250SX
    02 XR650L conversion
    84 ATC 480R

  13. #13
    Join Date
    Apr 2014
    Location
    Edmond, KS
    --
    2,531
    Quote Originally Posted by fabiodriven View Post
    I call BS on that.
    He kind of sounds like it to me too. Of course since I'm an electrical dummy, my opinion may not count for much here.

  14. #14
    Join Date
    Apr 2012
    Location
    USA
    --
    4,114
    Haha, I wish I knew electronics more. It's kind of like computers (yea, I'm actually a professional with computers lol). The end users use a mouse and click around in apps/programs. I know how to program, which on it's own is a HUGE field of knowledge to be had, I'm pretty good, but minimum actual proper schooling on it. Next step deeper is knowing assembly language, I've poked a tiny bit around that, that's literately to the point of 1's and 0's, meaning switches on or off. Beyond ASM, is the guy that designs/builds the boards. I'm far from that point, but I know a couple of the basics like capacitors, resisters, ac vs dc, diodes and such, but I wouldn't know enough without googling to build like a flashing LED light, I just know it uses a 555 IC timer, same thing used in like alarm clocks (I think).

    Anyway, I like electronics, just like I like computers. I hit a lot of topics and such, so I have a pretty broad understanding of things, but I can't pin point other things exactly. I kind of view electronics as part of knowing about computers, so it's kind of part of the same field =).

    Not to throw real life problems into this, but I'd love to work with an Adriano, which is a programmable micro controller. In theory a CDI box could be built based on one and be fully programmable and such. I can program, but I don't know the hardware side of things well enough yet. There's a lot of things that a Adriano could do though, like an electric controller for my wood stove to burn it at peak efficiency (most heat off the wood) when I need heat, and dampen it down when I don't need the heat. Even could go off the deep end and burn something small like wood pellets, and have an electric feed it controls. Anyway to get to the actual real life issue, I'm low on funds, so little fun projects like that I can't fund right now. Either need bitcoin to boom again (probably won't happen for 3-6+ months), or get more effort put into my business to make more sales, which in turn makes more profit. Been focusing on the business clearly which ironically is making more side projects (neutral/reverse sockets, speedo sockets, the project with Mike/Oscar, etc).

    I kind of wonder how things would have changed if I took electronics classes in 11th-12th grade or even in college. Heck it's really is an option yet once I have the spare funds. I wouldn't be going for any degrees, just the math and such classes to make more sense of things. Never took advanced math like calculus or trig, I think the most advanced math class I had was just algebra lol.

    I just did a little thinking, and if programming an Adriano is anything like I'm used to, building a CDI (programically/logically) should be pretty easy for me. The hardest thing I was thinking of was how to control spark advancement (The delays in ms), but you'd have rpm (ms time for 1 pulse), so not too hard to calculate 1 revolution into 360 degrees and math out the delay time to have the advancement point you desire. Like idle (1400 rpm) = 1400 spins per minute/60 = 23.333 rps (per sec), or 42.858ms per revolution. One degree would take 0.11904ms or 119.04us (I think that's the correct letters for 1000th of 1ms). probably a lot more technical than most people want to read, but it was an interesting thought, never hurts to have the idea wrote down encase I ever do it lol.



    Of course I'm not the first one to think of this, here's a video of someone that's done it already. Their code is opensource/public, but it's overly simple. It just fires based on the pulse signal (they used their own pickup instead of the stock pulse generator). That means no spark advancement at all or any fancy mappings like I'd want to do. It seems like their project is more of a proof of concept. Have to love the computer power supply CDI box though lol.

    https://www.youtube.com/watch?v=xYR3e3lAR70

    There's more videos too if you search for them on youtube.

    It seems like a neat project to take on, in theory there could be two mappings, one for cold start (ideal timing for running in cold weather at first startup), and fully warmed up temp mapping. I've seen a pretty simple thermoresister that bolts on with the spark plug and gives a head temp, not sure how reliable they are for the harsh atv world though.
    Last edited by ps2fixer; 12-13-2018 at 11:15 PM.

  15. #15
    Join Date
    Jul 2010
    Location
    Arkansas
    --
    2,196
    Quote Originally Posted by ps2fixer View Post
    if you want more advancement at max rpm, you have to physically change the pickup location
    Bingo. The max timing is physically fixed, no CDI is going to change that, even the expensive adjustable ones. The length of the pulse coil trigger also affects timing. In the case of the 350X, it would mean modifying the trigger on the flywheel.


    Back to your first post; I've been running that blue, finned CDI on my 200ES for at least five years. I forgot it even had the blinking LED because it's in the stock location under the tank, in the stock rubber strap. I just took a picture of it this morning.
    Click image for larger version. 

Name:	ATC200ESCDI (1).jpg 
Views:	10 
Size:	1.04 MB 
ID:	256140
    Click image for larger version. 

Name:	ATC200ESCDI (2).jpg 
Views:	8 
Size:	1.17 MB 
ID:	256141

    I changed the round to a square plug at the time too, and it's completely reversible if needed, back to the round plug by just releasing the terminals and installing them into the OE round plug.

    I also tried a few different Chinese CDIs at the time, some just ran (not right) and others worked OK, and yet others ran good. It's a crapshoot, but they're cheap enough to try several. One thing to note, the CDIs meant for smaller displacement engines typically have a higher rev limit or none at all (which is a bad idea anyway). Consequently, I've got a couple of new CDIs that I don't want to throw away, but just hang around in my tool box.


    Also, if you want to test actual spark energy, there are some relatively inexpensive tools for that.

    I've used these https://www.ebay.com/itm/Snap-On-MT2...sAAOSwQKlbAkRm

    They're still pretty basic, but it provides more valuable data compared to the adjustable gap type.

    I know oscilloscope prices used to be out of reach for the home mechanic, but they're much more affordable now and if you're really wanting to dive into ignitions, they're invaluable. Adding an assortment of transducers and cables as you go makes an oscilloscope the go-to tool for just about everything. Want to actually see the pulse coil waveform? It's not happening without an oscilloscope. Being able to interpret secondary ignition waveforms is monumental to understanding what is actually going on during the combustion process.
    The story of three wheels and a man...

//ArrowChat Integreation Code //