I have a 87 Quadzilla....

with the only mods being...

DG PIPE and silencer, Bored to .060 when rebuilt, roost boost, and I believe that is it...

It seems that it might be running a bit rich, because it will foul plugs up at times....It also seems that first and second gear don't really like to rev up quick, but once I hit third it will rev up quickly...

I was thinking I might need to rejet the carb, I've never done this before.. so where could I buy them, and what do I need?

thanks
Jason

 

Take out the main jet thats in there now to look at the number thats stamped on it. Go to your freindly local bike shop and buy 2 or 3 jets smaller starting from the one you already have. Start from the next size down from the original (do not skip a size) Go for a ride at wide open throttle, pull in the clutch and kill the engine, check the plug. It should be tan in color. If it's dark then put in the next size down main jet and go for a ride.

To adjust the jetting at half throttle, go for a ride at half throttle and keep it there for a minute or so, pull in the clutch and kill the engine, check the plug for color. adjust by raising or lowering the E clip on the end of the jet needle (centre of carb) lowering the E clip will raise the needle and richen the mixture at half throttle only. raise the clip to lower the needle and lean the mix ONLY go one position at a time do not skip a groove

The same applies for low speed jetting. There is a slow jet with a number that you can change.

ONLY DO ONE CHANGE AT A TIME...work on WOT circuit(wide open throttle) first, then half throttle, then the slow circuit
make sure you don't have a vacuum leak. Jetting will be impossible if the engine sucks air from the seals or gaskets. Do a leak down test to find leaks if any

hope this helps

87 zilla
87 quadsport