Restored timing chain. Starts in half pull. Runs like crap!!

[ATC110Riderz]

I redid the cam shaft sprocket & chain on my 79 atc 110 and it fires up with plenty of spark at the points and at the plug. The catch is, the stator and flywheel are from a later model atc 110. So, instead of 6 smaller coil packs on the outside of the flywheel, which is 79 and 80 stator design, this bike has been updated on the left crankcase only. So the stator is only 2 longer coil packs on the inside of the flywheel. What's weird is that the opposite color wire powers the bike, which I believe is the lighting coil. The remaining black wire doesn't power the lights. So my question is am I going to be forced converting the stator and flywheel back to original year? The current stator & flywheel was designed when cdi took over the points. I had this bike running for about 2 weeks, timing moved or something, as the timing chain was overdue. Anyways, initial ignition is superb, unfortunately, as soon as gas is fed into it, it misses and spits. Is this a timing issue or power issue? Or something else?

Please help

[ATC110Riderz]

33 people viewed this topic and had nothing? Wow.

[tri again]

Hey there and welcome.
You obviously havea:
service manual
?
It should light up as a clickable link.

Long weekend...everyone is out riding but someone who knows will
chime in.
I've often thought of making it possible to use either coil in case one fails on the trail.

so it starts with 1/2 pull and is ridable?

spit and miss is usually dirty carb, slow jet is super tiny like.010 or high 'e' guitar string.
I've also had miraculous results by nipping the last tiny bit off the spark plug wire so the cap has fresh copper to bite into.

PuHlease keep us posted.
We all need to know this answer.

[ATC110Riderz]

Thanks for responding. The bike fires up nicely. Sometimes sounds descent at 1/4 throttle in neutral, yet still not holding rpm. No throttle response when thumbing the throttle. Just spitting and missing. I just replaced the timing chain and reset the timing to the best of my knowledge as explained in these forums. I even took it back apart to see if I was a tooth off on the cam sprocket in both directions and in one direction it didn't fire and the other direction gave the same result for the most part. Maybe I will clean the carb. Its been a timing issue with it and the carb is only a couple months old as I've replaced it already.

[ATC110Riderz]

I guess I should mention it has new ignition coil and condenser, spark plug and wire, carburetor, timing chain and points..... Stator and flywheel are from a 1982 atc or later left crankcase, I have two of them not knowing they were not OEM. I have a lot of hours into this thing. This is my last resort.

[badass350x]

Just because its a new carb doesn't mean you don't have dirt in the carb especially if you didn't clean the tank out prior to installing fresh carb.

[ATC110Riderz]

The gas tank was etched before the carb was changed but I'm still going to try to clean it

[Chopsaw]

Spits out carb or exhaust ? Does choking it help with the flat spot ?

[effort=results]

I would check if the flywheel on the 82 has the chuck location the same as the original. I don't know but if that's different than what tdc is would be different. And if so try advancing or retarding a tooth. If I remember right the 82 to 85 had a sight window for timing and the older ones had to remove the pull start to time it to a notch on the stator. I bet your way out of time .

[big specht]

sounds like you have a cdi stator set up OR its a 12v primary coil I think the points 110s were 6volt ?? possible coil issue? Depends on what you are planning on doing with it you could convert probley it over to cdi

[ATC110Riderz]

Is it possible to convert the 79 and 80 atc110 from points to cdi?

[ATC110Riderz]

I would check if the flywheel on the 82 has the chuck location the same as the original. I don't know but if that's different than what tdc is would be different. And if so try advancing or retarding a tooth. If I remember right the 82 to 85 had a sight window for timing and the older ones had to remove the pull start to time it to a notch on the stator. I bet your way out of time .


That's what I was wondering. If I'm not mistaken they are the same markings at tdc. I only say that because u can feel the end of the stroke as the T mark slides by the hole. I may be wrong. But again, I've had this bike running for awhile. Then it started missing again, I would be riding and it would seem as if the bike shuts off for a split second and full power emerges again. I found that the timing chain was so worn the tensioner was no longer touching it. I changed it thinking my timing simply moved because of the sloppy timing chain... After changing it, I found 3 different teeth the bike will fire on but none of them without missing, popping, hunting, sputtering, dying. I will try a couple things based on what I've been updated with here.

[ATC110Riderz]

Yes the cdi models run a 12v primary and the points models ran a 6v. We have a yellow wire coming from the lighting coil powering the lights and accessories, like all the 110s, and a black wire which powers the ignition coil and points. In my case, since the left crank has been updated from the original 6 coil pack stator to the 82 stator... the yellow wire (lighting coil) gives the bike spark, and only the yellow one. The primary seems useless as it doesn't power the lights and accessories, because they run 6v as well. I've never used the primary coil wire. The bike did run at one time for awhile. While running off lighting coil.

[ATC110Riderz]

Spits out carb or exhaust ? Does choking it help with the flat spot ?


Spits out the exhaust. Choking used to make a difference but the more parts I restore, the more it changes. She's old but has alotta good parts on it.

[barnett468]

ok,

yiu said there are 3 teeth the bike would fire on. there is only 1 proper setting, just use that.

did it run fine before the repair?

no carb changes that could cause the prob?

if the gas is old and the color of apple juice or darker it is bad.

if gas is good and cam timing and valves are properly set i would do the following.


get eng on compression stroke.

remove plug and instert a screw driver in plug hole.

slowly rotate eng until it feels like the piston is at tdc.

move flywheel back and forth until tdc is narrowed down as close as possible.

look at timing mark on flywheel. if it is extremely close then the location of the marks is correct.

if they are correct put white out on the fiure mark.

connect timing ;lite.

start bike in semi dark place.

see if it fires on the mark.

also see if the lite misses along with the engine miss. if the lite is not steadily flashing you have an electrical problem but not a timing problem.

backfire out carb is either tight or leaking ex valve or improper ignition timing providing the cam timing is correct.

[effort=results]

Update? Was it your stator. I know have a 90 beating me down.