2 Stroke 97 cr 250, aka death bike

dreezy

dreezy

A buddy of mine picked up a cr on the cheap at the beginning of the summer. It's not only his first dirt bike, but his 1st ride on it was only his second time ever on a dirt bike. The first being on an under powered atk 250 I used to have and it lasted all of 2 minutes.

The death bike name comes from a throttle issue. It seems to run fine other than a choppy idle all day. However out of no where the throttle will stick wfo. It has now almost sent him into the trees. The second time we were on a two track and he had to lay it down.

I told him to get a top end gasket kit, my guess being the gasket at the reeds is bad, or even bad reeds. Has a new air filter, carb has been cleaned and the boot looks to be good as well. It's always sparatic and it doesn't apear to be a throttle cable issue either.

I think it may be related to the shifty idle, but I really have no idea. Just wondering if any body else has had a similar issue and what the culprit was.
 
SRAD97750

SRAD97750

Moderator
Staff member
If its an air leak, it will rev out of control, but have no power because it's a lean condition. With the throttle opened, the lean condition is mostly corrected. I doubt it's a gasket problem.

Stuck at WIDE OPEN is a cable/slide problem 99% of the time. If you turn the bars all the way, you may be moving the slide up without visually noticing. The cable may be catching on something every once in a while. Sometimes sand or dust can jam up a slide and cause it to stick at certain openings.

SAFETY in mind,
I suggest removing the cable completely and clean, inspect, and replace if necessary.
I suggest cleaning the carburetor and slide really well with alcohol.
Test the freedom of movement in all scenarios.
-BIGDAN
 
cleonard

cleonard

+1 on that.

Carb's are wear items. It takes a while, but they can and do wear out. Give it a good cleaning and see how it works. Alcohol is good, but get a can of spray carb cleaner. Be sure to scrub with a toothbrush or something like it.

By the way cables can look pretty good and still be messed up.
 
dreezy

dreezy

My fault on not trying to figure it out myself and not realizing my buddy misses the most obvious things.

Where the cable enters the throttle tube, the screw was coming out and not allowing the cable to return holding the carb open. Bike needs a new throttle cable is all.
 
dreezy

dreezy

And because everybody loves pictures

IMAG0209_zpsdb7c2a03.jpg
 
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