New thumper owner

 

I just traded a boat for a '76 Yamaha Thumper in almost excellent
condition.. Seems to smoke quite a bit when cold.  Is this a common
problem?? The previous owner said it really smokes after it's been
trailed somewhere.. I'm talkin 3 or 4 minutes mosquito control white
smoke.  Cranks pretty easy after it's warmed up.  Lots of power, fun to
ride.

I can remember when the Thumpers first came out and my Dad droolin over
one.  Brings back lotsa memories and now, I have my own.

Any ideas on the smoke??

Paul in Anchorage.

 



xt500? the white smoke is not good. does it also feel like
it's grinding rocks when you move?
you need a good mech to check it out. it could be serious.
i have several sr500's, same motor, slightly different
gearing.
have it checked.

 

e wrote:

No rock grinding, rides and drives real nice.  The white smoke goes away
once it's warmed up.. It appears to come out of the entire muffler from
behind the engine as well as the muffler itself.  I'm wondering if there
may have been some condensation build up in there..

 



no, sounds like worn valve inserts.