Ok im new here as well as becoming a mechanic so if i dont know certain terms, ill just use google lol.

Anyways i have a old yfm 200 85 or 86 (reverse). What im trying to do is get it to start like new atvs. Yeah its a old engine but i still want it to start right up on the first pull not 3 or 4 pulls.

Recently what i have done to it is - clean carb, rejetted, spark plug (gap), air filter, drained the gas because it was stale and left almost a ear wax in the carb. Now working on the eletrical start and oil changes when i get more time

Any ideas? (valves , piston cleaning, spark arrestor...?) any thing i can put in the gas thats safe to remove the carbOn from the piston?

 

I think starting on the first pull is probably overrated, easy starting is usually at the expense of better power. In older cars it was compensated for with advance on the ignition timing, where it was retarded for starting and then 'advanced' as the engine increased rpms. I'm not sure how it's done on atv's but I bet its not a state of the art ignition system.

On the other hand, my single cylinder air compressor started a lot eaiser when I replaced the spark plug. Also, most engine diagnosis starts with a compression test.

You probably see a big difference in how many pulls it takes when the engine is being re-started immediately after shut off vs. when it has been sitting for a day or more. Sorry I'm not much help.

 

No its fine haha. Well as for the eltrical start, if and when i got it working, if i took off the umm rotor with the starter coils and replaced that, would that help the eletrical start?

 

I believe if you are getting a consistent blue spark then changing the staor/CDI/coil isn't going to help.

When you did all the other work did it make any difference?

 

Search tradebit.com to see if you can find a pdf service manual for it.
I have only worked on a badger 80 and a 660 grizzly but but have unusually high compression, @ 145 lbs min and 175 lbs normal.
Assuming it has adequate compression, and runs fine, there is not a lot that will help it start better. New plug maybe, make sure choke is fully closing and float level is proper.
Set the valves or at least check them to be sure they have correct lash at top dead center.
Ken

 

I would clean the gas tank out, remove it and turn it up side down flush it with a bit of gas, remove the stop **** ( fuel shut off ) from the tank and clean the screen ( filters ) on it. Look in the tank for any sludge or crap build up. Replace the rubber gas line to the carb. U say u jetted it. Did u do a rebuild on the carb? a kit is only 20$ to rebuild it. With it's age it should be rebuilt. If u jetted it you should probaly add a k/n or uni air filter to let more air in to match the new jet letting more fuel in.
Good luck