//ArrowChat Code
Page 1 of 2 1 2 LastLast
Results 1 to 15 of 16

Thread: 1982 atc185s poor proformance at high rpms. igntion coil?

  1. #1
    Join Date
    Aug 2018
    Location
    Little Rock, Arkansas
    --
    40

    1982 atc185s poor proformance at high rpms. igntion coil?

    Bike has a mid oversize cam, kibble white valve springs. .75mm oversize piston 105 main jetted carb. 6.13 sprocket gear ration with 25 inch tires. Rides perfect from idle to mid range and starts cutting in and out at high rpm. Possible ignition coil? Im stumped.

  2. #2
    Join Date
    Apr 2012
    Location
    USA
    --
    4,114
    Have you tried moving the main needle up a notch? I'd target carb tuning first since that's pretty easy to ABA test. Besides that, check mechanical timing (cam vs crank), and if you have a timing light, check the ignition timing. Talking about ignition timing, are your spark advancer springs in good shape? They are what controls the spark advancement, also the whole assembly should move freely besides the spring tension.

    For the cutting in and out, does it seem like it's just loosing spark, like a bad connection/wire, or is it popping, backfiring etc? Maybe disconnect your kill switch (black with white stripe wire) and test ride it real quick to make sure that's not the problem. Never ran into a bad one personally, but never know.

    Also, are you running the OEM CDI, or an aftermarket/Chinese one? I've noticed the Chinese one's don't do well at high rpm when I was testing them on my 350x. A timing light would probably show what's going on if it's ignition related like that.

    Kind of the same thing for the ignition coil, you're running the OEM one right? I've heard from more than one source the Chinese orange "racing" ignition coils are junk, weak spark and such.

    Just throwing ideas out there, hopefully it's just something simple though.

  3. #3
    Join Date
    Aug 2018
    Location
    Little Rock, Arkansas
    --
    40
    I have tried the clip on every groove on the needle, seems to run best on the 2nd from the top. I believe it has both the oem coil and cdi box. I've checked and double checked my timing.
    Already replaced my ignition advance springs with NOS OEM springs, the old ones were weak and rusty.

    It feels like its just losing spark, like its cutting in and out. Is a bad ground sound likely? Will check killswitch.

    Click image for larger version. 

Name:	20190602_004625.jpg 
Views:	28 
Size:	2.86 MB 
ID:	258726

  4. #4
    Join Date
    Apr 2012
    Location
    USA
    --
    4,114
    The only bad ground I can think of that would cause this is the green wire between the CDI and Ignition Coil, and the Ignition Coil to frame interface.

    The marking on the CDI is what OEM has, so it probably is OEM.

    The CDI typically fails in a couple different ways, complete dead with it does nothing, and intermittent which can be broken solder joints inside the housing for the connector. The capacitor inside is 30+ years old and most good brands of capacitors start to fail around 20 years (age kills them, not so much the use). It's not uncommon for the CDI to be at fault. If you can't find anything else bad, then normally the CDI is blamed. You could try to do the multi meter test in the service manual on it, last couple people that tested them had them test bad that way and replacements fixed their issue.

    There's a Chinese CDI with a teal connector that seems to do fine, only problem with Chinese stuff, you never know when they change the design and there's no model markings at all. The other option is to buy a CDI from Mike, his uses a different connector (more modern style), so you'll need an adapter off him too. Full disclosure, I make the adapters for him. The CDI you'd need is labeled as for a 200x which uses the same mechanical spark advancement system as most 200cc series engines from this era. The CDI might have some extra ignition timing added in to be more aggressive since it's tuning is from a stock 200X CDI. I'd think your machine should respond well to it though since you've done some mods to the engine. Anyway, I linked his site below, talk to him about it. Prices are pretty reasonable from what I've seen.

    http://mikesatvfix.com/

    If you have another 83 and older 200 series machine around, likely the CDI is the same pin out and has the same ignition spark curve in the CDI, let me know if you do have another and I can try to check into it. Swapping with a known good unit is one of the best ways to test for CDI issues.

  5. #5
    Join Date
    Jul 2009
    Location
    South Florida
    --
    6,722
    Try pulling the choke up at the instant the motor starts to miss , if it kinda clears up and revs then it’s a carburetor issue .
    In my experience the cdi on this model when they are bad they just stop working as in no spark .
    A poor solder connection at the stator or weak stator will cause your symptoms as well . Oem
    Coils very rarely go bad on this model but when exposed to the elements they will .
    78 atc 90/180cc Dickson Full Suspension
    76 ATC90/180cc Nicholson
    77 atc 90 Dickson Full Suspension
    84 KLT 110/123cc Powroll Racer from 80s
    87 atc 125m stock
    84 atc 200x Curtis Sparks
    84 atc 200x Powroll My race bike from 80's
    83 atc70/108cc Powroll blue Xmas Special
    81 atc185s HP-ATC full suspension

    Performance Shop is Open PM me for Service

    My Feedback http://www.3wheelerworld.com/showthr...ck+shortline10

  6. #6
    Join Date
    Aug 2018
    Location
    Little Rock, Arkansas
    --
    40
    I cant tell be the picture on there website, but is the adapter wire a square plug? Like the picture attachedClick image for larger version. 

Name:	20190602_124752.jpg 
Views:	23 
Size:	2.72 MB 
ID:	258729

  7. #7
    Join Date
    Aug 2018
    Location
    Little Rock, Arkansas
    --
    40
    Shortline i tried choking it, does not change the surging, i will ohn out the stator. Do you know where i can find a decent close to oem replacement? Cause at this point im about to start replacing everything.

  8. #8
    Join Date
    Apr 2012
    Location
    USA
    --
    4,114
    CDI looks like it was stuck at the bottom of a mud hole lol. Might want to just try to clean it out and see how corroded the pins are.

    If Mike doesn't have the right adapter on hand, I can make one for the same price he'd charge. I can't recall if I made any for him for this old of a machine or not, 84-85 used a round connector, and 83 200x used a different type of square connector (two in fact). Basically all Hondas 86+ used the same connectors as Mike's CDI, and most 83 and older used the same as yours.

    I haven't really done the stator rewinding stuff yet, but I'm basically tooling up for it. Seems like it's easy, just a lot of time involved turning wire. Another thing to look for is the wires coming out of the engine (from the stator), if they are damaged, or extremely stiff it's possible it has a broken wire, really any wires in the harness have that risk with how old these machines are. Inside the wrapping they normally do really well, it's the ones that come out to connect to things is where they get weathered.

    I suspect the actual stator windings are fine, the lead wire going to the harness would be my primary concern stator wise.

    I highly suggest replacing parts one at a time, no reason to replace 5 parts at once and get new issues and not know what caused it. I've seen that done too often. I once bought a Toyota Pickup with 512k miles and the guy threw in something like $500 worth of parts to try to get it running. All he had to do was turn the key on and notice the check engine light never comes on, it had a bad computer from a rust hole and salt water got into it. $40 used part and it was up and running.

  9. #9
    Join Date
    Jul 2009
    Location
    South Florida
    --
    6,722
    78 atc 90/180cc Dickson Full Suspension
    76 ATC90/180cc Nicholson
    77 atc 90 Dickson Full Suspension
    84 KLT 110/123cc Powroll Racer from 80s
    87 atc 125m stock
    84 atc 200x Curtis Sparks
    84 atc 200x Powroll My race bike from 80's
    83 atc70/108cc Powroll blue Xmas Special
    81 atc185s HP-ATC full suspension

    Performance Shop is Open PM me for Service

    My Feedback http://www.3wheelerworld.com/showthr...ck+shortline10

  10. #10
    Join Date
    Apr 2012
    Location
    USA
    --
    4,114
    Interesting, never thought about the Chinese/Taiwanese coils. Wonder how well they last and if their winding spec is close to OEM. Might have to sample one from my Chinese supplier some time. Price is right that's for sure.

    Feedback seems a bit hit and miss on that stator, the one I looked at from my Chinese supplier looks a little better built, but they have been hit and miss for quality, their harness wire is just trash.

  11. #11
    Join Date
    Aug 2018
    Location
    Little Rock, Arkansas
    --
    40
    For the sake of resolving a thread, an older mechanic i work with explained what i did wrong. So i increased the size of the piston and increased how much air the cam allowed in. While leaving the original carb thinking i could just increase the mainjet size. What i failed to realize is that the larger piston and cam are pulling more air through the same size hole, increasing the vacuum pressure on the main jet. So by putting a larger main jet i was flooding the engine at high rpm smoothering the spark. I put a 92 b keihin jet in (smaller than stock), instead of the 105 keihin jet. My atc185s runs beautifully now. Rpms toping out around 5800 according to my digital tachometer!!!

  12. #12
    Join Date
    Apr 2012
    Location
    USA
    --
    4,114
    Nice catch and advice there. I've always heard people going bigger, but the description makes sense. I was guessing it was lean which the choke would help with, but rich is a little harder to diag, about the only thing I can think of is a plug check to see if it's black.

    You could tune the carb a bit more and adjust the needle 1 clip higher and lower, and see if it runs better in either direction.

  13. #13
    Join Date
    Aug 2018
    Location
    Little Rock, Arkansas
    --
    40
    Currently fine tuning. At this point im just glad to have the last 900 of my rpms back.

  14. #14
    Join Date
    Jul 2009
    Location
    South Florida
    --
    6,722
    Glad your figuring it out , a .75 over piston and mid range cam shouldn’t change the stock jetting unless it’s a high compression piston .
    The stock carburetors are sensitive to their intake , are you running the air box lid ? Stock exhaust ?
    Factory jet is a 98 and going to a 92 isn’t a huge difference just make sure you check the spark plug color to make sure it’s not running to lean , you want a medium brown color .
    78 atc 90/180cc Dickson Full Suspension
    76 ATC90/180cc Nicholson
    77 atc 90 Dickson Full Suspension
    84 KLT 110/123cc Powroll Racer from 80s
    87 atc 125m stock
    84 atc 200x Curtis Sparks
    84 atc 200x Powroll My race bike from 80's
    83 atc70/108cc Powroll blue Xmas Special
    81 atc185s HP-ATC full suspension

    Performance Shop is Open PM me for Service

    My Feedback http://www.3wheelerworld.com/showthr...ck+shortline10

  15. #15
    Join Date
    Aug 2018
    Location
    Little Rock, Arkansas
    --
    40
    Shortline yeah i got a little carried away with my jetting, but i tried a 105, 110, 102, 98 in then the 92. The 92 did the best by far.

    I installed a factory 82 air box (no removable lid), the previous owner thought it didnt need an aircleaner. Hence the .75 over piston and bore. And stock exhaust.

    What other upgrade options are there? I dont necessarily want more power, im just looking to make them machine preform better. Smoother acceration, wider power band, smoother shifts, etc.

    Is a performance exhaust worth it? Are there different options for heads? Are high compression piston reliable? Can i upgrade my clutch?

    Im just wanting to see what my options are.

//ArrowChat Integreation Code //