87 xr100 bends valves

well you guys helped me get my old xr running a while back and im about ready to fix it again. last time i fixed a ton of things on it including the intake valve it ran for about 2 days and it bent the exhaust valve and the new intake valve is hitting and probbly was getting ready to bend, i lined everything in the timing up eXactly and checked it about 100 times b4 i put it together..... my best guess is the chain tensioner was not correct( the nut was"literally" tight on the outside but that would in turn mean the tensioner was loose b/c its lobe shaped)

the flywheel or hub would spin w/out the motor turning over like the chain was slipping on the gear down in the bottom..... alot of you on here told me that bottom gear dosn't wear out that often and that probly wasn't the deal, what do you guys think, i am 100% i can get it running in about an hour, but i know its about to bend the other valve

help me if you can

geez man just go buy another bike and save your money or put it towards another one

If the flywheel turns without turning the motor the key is missing or sheared and the nut isn't tight enough. If this started happening before you bent the exhaust valve its the problem. Pull the flywhee and clean the bore and shaft, get a new key and retime it. Make sure the tension side of the chain (front) is tight when you time it.

just get a newer xr100 and save your self the trouble I have never had problems with mine

just get a newer xr100 and save your self the trouble I have never had problems with mine

You know a lot of people on this site just don't understand what a bike (no matter how old) means to people. I have seen many comments about getting a new bike on some of my posts, but I never give it a thought. When you have been through some of the things I have with my bikes, you just want to keep them running forever and not give up on them for some new flashy bike. So toyvette81, even though I don't have any advice for fixing your bike, I say keep her runnin' if she is that special to ya, and don't listen to these guys that say their bike is so much better.

Well if you want to sell it and can ship it to NJ. I have a 2002 xr80 motor looking for a home. Maybe I can use the chassis w/o the motor if you are interested.

It's not they don't understand, they just don't have anything intelligent to say so they come up with those brilliant suggestions. :D

Time to tear her down... Go fresh from the crankbearings up... Since it's an 87 you might want to upgrade to a CDI ignition. Engines only makes a stepped flywheel key for the modification...

Seems like you are chasing an issue that may be made up of several things... :D

Oh yeah... as for the folks saying sell it or get a new one... It takes all kinds to make this crazy world go around...

They are the folks that have to be here... That we can be here too... :D

sometimes you have to let the things you love go

my EX Ol' lady is up for grabs... she's great with tire warmers and an umbrella!

there ya go

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