You are here:

Motorcycle Repair/1976 Honda cb550f


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

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  

Motorcycle Repair

All Answers

Answers by Expert:

Ask Experts


Bill Silver


Need help with vintage Hondas from the 1960s? I am an expert with 250-305cc bikes in particular and most all of the other pre-91 models, in general. I do NOT claim to have a great deal of experience on Gold Wings, Cruisers, ATC/ATVs and dirt bikes.


I have owned/ridden/maintained Honda motorcycles for 35 years. I have written five books on Honda repairs and collecting. I was a service manager for two Honda shops back in the 1980s.

VJMC (Vintage Japanese Motorcycle Club) of North America

VJMC newsletter, as editor for two years and as contributing editor currently.

3 years auto shop in high school, teacher's aide in Automotive Technology in Jr. College, Diesel mechanic course in college, self-taught mechanic and automotive writer.

©2016 All rights reserved.