AllExperts > Motorcycle Repair 
Search      
Motorcycle Repair
Volunteer
Answers to thousands of questions
 Home · More Motorcycle Repair Questions · Answer Library  · Encyclopedia ·
More Motorcycle Repair Answers
Question Library

Ask a question about Motorcycle Repair
Volunteer
Experts of the Month
Expert Login

Awards

About Us
Tell friends
Link to Us
Disclaimer

 
 
 
 
About Bill Silver
Expertise
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.

Experience
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.

Organizations
VJMC (Vintage Japanese Motorcycle Club) of North America

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

 
   

You are here:  Experts > Shopping > Motorcycles > Motorcycle Repair > 1982 honda cm250c

Motorcycle Repair - 1982 honda cm250c


Expert: Bill Silver - 11/3/2009

Question
Hey bill, you seem like the most credible guy on here to ask a question about this thing. Ive had it for about 3 weeks now. at the start it had a wiring problem and would not start. my old instructor had a 200 model sitting in his garage that he gave me to mess with hooked after a little tweeking it ran but it ran really choppy when there was a load on it. so i switched to the 250 with the 200 harness and i got the same problem. i have to clue what to do to make this thing run the way it should. please help me

Answer
Sean, misfiring under load problems can stem from several causes.

I guess you know that the ignition is CDI, so not adjustable. Pretty much works or it doesn't, however the CDI modules can fail and give erratic output. You need to put a timing light on it when it is running in neutral and see if the timing advances as you rev it up. CDI ignitions are self-powered, so don't need the battery to make sparks. The battery is a load for the charging system output and a dead, dying or missing battery will cause the charging system to go full output and fry light bulbs and other electrical components. I would check the spark plug caps for 5k ohm resistance values and use fresh spark plugs.

IF the bike was sitting for a long time, the whole fuel system needs cleaning from gas cap to float bowl. If the bike has had mods to the intake or exhaust system, the OEM carb jetting calibrations may not work now.

Make sure that the valves are adjusted and compression readings are around 150 psi or more.

http://www.cmsnl.com/honda-cm250c-custom-1982-us_model1045/partslist/ for parts references.

Bill Silver

Ask a Question


 
User Agreement | Privacy Policy | Kids' Privacy Policy | Help
Copyright  © 2008 About, Inc. AllExperts, AllExperts.com, and About.com are registered trademarks of About, Inc. All rights reserved.