Motorcycle Repair: mz 251 2 stroke bike, stroke bike, vacuum hose

Question
hi mark, i have the above bike and recently it loses all power wont start then after 10 minutes or so will start but cut out and backfire sometimes.

im told the diaphram may be split inside the carb somewhere?
the plug is new there is a good spark all electrics are ok.
when its running its good but cant go on a long journey?

any advice and how difficult is it to repair?

many thanks
ian scott

Answer
Hi Ian,

Was the MC stored or not started in a while?

Was any repairs or maintenance performed recently?

Quick checks:

1. Inspect the air filter and air intake ducts if any. Bees, spiders, mice, and birds love to obstruct these places with their nests.

2. inched or collapsed fuel or vacuum hose.

Can you check cylinder compression? I would like to know the sealing properties of the combustion cylinder.

Send me an email: mshively1@woh.rr.com

I'll return several infromation files that will assist you with diagnosis and repairing your MC.

Respectfully,
Mark Shively

Dayton,Ohio USA