Rebuild top end on 85' 200x "how too"

[robert leon]

ok guys this is my first 4 stroke atc ive rebuilt my 250r's but never 4 stroke. ive already pulled the motor. i need to know what to do and what not to do? im gonna order new rings and seals. the motor has no compression at all and starts every now and then. if there is any good advise before i start it would be much appriciated.:wondering thanks

[SteveCZ28]

Have you used a compression tester on it? Maybe timing jumped a tooth or 2 and the valves are staying open or opening to soon.

[robert leon]

no never how do i check? i need to put some new seals because there is oil coming out the middle of the jug.

[zackwhite]

take the head off and look at it

[robert leon]

the head looks to be fine.

[robert leon]

i want to take the timming cam out. i dont want to mess up anything cause i dont have the book. is there marks or should i mark it and reinstall it back at those marks later? like i said dont really know alot about the 4 stroke

[zackwhite]

if u wanan check trailprotrailpro timeing take the hole cdi off the top end with the top end on the motor and take out the lil scrow on the same side down bye the timeing chain tighter bolt.take it out and line up the T mark with the lil mark on the case by that hole.and then line up the 0 mark on the cam sproket with the mark on the time of the head .if u can turn the bike over to the t mark and the others r lined its in time

[tri again]

i want to take the timming cam out. i dont want to mess up anything cause i dont have the book. is there marks or should i mark it and reinstall it back at those marks later? like i said dont really know alot about the 4 stroke

whoa, go to the
'world class help' section and get a free manual.
They seem to open ok with acrobat reader version 4, which is an old and very small version.

I've seen way too many cam timing questions on here to even attempt it without
before and after pictures and all the advice I could get.
If it had no compression but starts sometimes?
it could easily be a valve hanging open.
Maybe even as simply as a bad compression release, IF the x even has one.
I know the 185 and 200's do.

[jordan_muirhead]

i believe the 200x does not have the decompression release

[robert leon]

Ok that's a lot guys

[Chazz of Blades]

Not sure about the 85s, but my 86 engine has a decomp lever.

[Chazz of Blades]

The 86 has an automatic decompression attached through the kicker. It's on the top left corner of the engine, on the clutch lever side.