Motorcycle Repair: 1990 suzuki DS 80 no power, suzuki ds 80, needle valve


Question
Thank you for taking my question.
serial# 8m2100094
How can I get this bike to have power. When you give it throttle it does not rev up all the way. I have replaced the needle valve and seat, installed a in line fuel filter,changed the spark plug. I also checked the compresson and it was 135#. Could this be because of old gas. I was told it had sat for a year when i bought it.
       THANKS AGAIN.

Answer
Hi Clint2,

If the engine is not revving, inspect air intake restrictions and fuel delivery.

It's important for the carburetor to be clean. Varnished fuel obstructs jets and fuel passageways.

The problem may be a tuning issue, a varnished carb, or both. It may be some other problem. If the MC was stored a year, the carb will need thoroughly cleaned. Do this before doing any other work.

Learn about reading spark plugs to know how to tune the carb air-fuel mixtures. Visit "www.ngk.com" and then click "Spark Plug 4-1-1" review the left menu topics.

I return tech files by email. There was no email address with your question as requested.

Respectfully,
Mark Shively