Motorcycle Repair: 1976 Honda cb550f


Question
Hey  Bill,

sorry what i meant was the engine will crank and not start unless i give it throttle with or without choke.

so i give it some throttle and engine will run until i let go of throttle then it dies.

ideas on where to start now? doesnt sound like a spark issue

Answer
I gave you all the answers in the last question.....

Bikes don't start up like a car with automatic chokes or fuel injection. They are cold-blooded and need choke AND throttle to warm up. IF the idle circuits are clean, float levels set properly, fuel system clean from top to bottom, valves adjusted for maximum compression readings of about 175 psi and the ignition timing set properly, then the bike will be hard starting and not idle once it warms up. Decent warm-up time is about 5 minutes.

If the bike has been sitting for a few months with gas in the float bowls, then the idle jets are most likely plugged up and the carbs need to come off for cleaning. There are many, many facets to this problem that can be potential issues preventing proper operation. If the bike has poor compression it will never run properly, no matter what else you do to it. Compression, ignition timing, fuel metering are all factors that have to be spot-on, otherwise you are beating your head against a wall. You haven't supplied all the specifics to narrow down why it doesn't idle, so I have given you just about all the possibilities to work from, so the bike can run properly again.

A repair manual will show you step-by-step instructions on how to do tune-up procedures. There is no one cure piece of magic to do here to make it behave. You must follow all the steps I have outlined for a successful result. If these procedures are beyond your abilities then you will have to recruit someone local to help you overcome the roadblocks to success, but reading a proper shop manual will get you headed in the right direction.

Bill Silver