Jump to content
Sign in to follow this  

87 xr100r smoking issues

Recommended Posts

Remove all Advertisements

Ok so i have an 87 xr100r and when i got it it had some issues as follows

- timing was off 2 teeth - fixed that

- helicoil for spark plug tube - fixed that

- no compression - removed head and shard of metal had odstructed intake valve from closing off all the way - fixed that and relapped both intake and exhaust valves and they now fit and close off perfectly, but only the exhaust valve has a seal and the intake seat cone is not fitted for a seal and i also removed the piston and rings look new and cylinder had recently been honed - i bought this bike from a guy that i think tried to work and could not get it to run due to timing being off and no keyway so i fixed that too. Anyway my question is the bike smokes like a 2 stroke and i am wondering why the intake valve has no seat and could that be my smoking problem????? The top end kit came with 2 valve seals and i put 1 on the intake but it streches the seal (badly) and the cone is tapered and i thought the seal could slide off and obstruct valve opening or closing so i removed it before reinstalling the valve spring and now it smokes like a 2 stroke - all the online microphish i have found only shows a valve seal for the intake and not the exhaust so why is my bike backwards?????????? I am trying to get this bike running well so i can tear it down and basically restore it for my son for christmas. Any help would be appriciated. Pardon my spelling errors.

Share this post

Link to post
Share on other sites

Someone replaced the '87 head with one from an earlier year XR100, if you look at the microfiche diagram for an '82, it shows an exhaust valve guide seal and no intake seal.

The top end gasket kits are generic, and will include two seals, even if you only need one.

IMO, have the cylinder mic'ed for wear, have it bored to the next size, and get a new piston and rings, that way, you know what you have. Just because a cylinder "looks good" and rings "look new" doesn't mean they aren't worn beyond the service limit

Share this post

Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this