I really don't know a whole lot about tuning old bikes ( I'm 18 ) ... It's a 1980 KZ-650E1 LTD with an aftermarket coil, Kerker exhaust, bigger Spark plug wires, and a Straight feed petcock. When my dad first got the bike it ran great.. couldn't even hold on to the bike... but a buddy of his told him he should put the OEM petcock back on it ( it had a Drag style Petcock on at the time) so he did... silly us didnt know what we got ourselves into with the whole vacuum petcocks ( a blast from the past)... so soon after the diaphragm goes bad in it and we rebuild it... at this time the bike wasnt running like normal... so we took it to a guy at a bike shop and he got it to run better... but still not as good as it did before.

So after a year of tinkering with the timing , dwell, cleaning the carbs/jets, and i did put a drag petcock back on it... he got angry with it and gave it to me instead of selling it... i don't want to sell it because its a great bike...but it just isnt the same... anyone know what I'm doing wrong??? No one around here seems to want to work on them... What can I do and go over to tune it back to its ball breaking power?? can anyone give me a list of things to go over??

 

Would you by chance have the numbers written down in your manual?

 

have you tried to sync the carbs since you rebuilt them? you could always get new plugs and wires for it. i'm not to sure what else you have done to the settings so it's hard to help you out with fixing it.

 

well.. we havent really messed with much... haven't touched the carbs settings... only the timing and the dwell... the carbs have bigger jets for the exhaust... the bike gets up to 5500 or 6000 and starts getting pretty choppy... also where can I find a mercury carb sync tool??

 

Also, should I get a factory service manual... or a clymer service manual... I know my bike has 4 cylinders.. .but what KZ650's were considered Twin Models???

 

i would go with the cylmer mannual it's a little bit easier to follow than the factory mannual is.

 

Thx.. btw i love your helm... thats the one i'm gonna get after i get this bike up and running right.

 

hmm, at 6k rpm, and it is missing? Maybe the main is too fat for the needle taper. Step down to a smaller main while keeping the needle. What was the wfo plug check?