HEADS UP!!!

Site upgrade in progress... Core site functions are working, but some non-critical features/functions will be temporarily unavailable while we work to restore them over the next couple of weeks.

Please post any bugs you encounter, but before you do, check to see if it's already listed.

Thanks for your patience while we work to improve the community.

Sign in to follow this  
Followers 0
stickk

New to me '01 426, ran good, now doesn't

7 posts in this topic

Test rode on street, ran it through the gears and it ran very well and crisp. Took it out to the trails and it ran very well. Went riding yesterday and the bike did not run great. As long as I rolled the throttle on easy it was fine, but when giving it a healthy amount of throttle it would sputter.

fresh gas, plug looked fine. the only thing i changed from the previous 2 rides was a new air filter.

Any thoughts? Thanks.

Share this post


Link to post
Share on other sites

Check out your Accelerator pump diaphragm see if any good if you open you thorttle open fast it should spray fuel in to the intake of the motor to much can make it bog to little make run lean.

Look up BK Carb mod

Check the jets and the bowl make sure you dont have dirt in it it could be a clogged jet.

On you new Air filter did you over oil the air filter.

Is your hot start valve all the ways closed if it hangsa open it run LEAN thats bad.

Is you chock off it cause to run rich.

Test rode on street, ran it through the gears and it ran very well and crisp. Took it out to the trails and it ran very well. Went riding yesterday and the bike did not run great. As long as I rolled the throttle on easy it was fine, but when giving it a healthy amount of throttle it would sputter.

fresh gas, plug looked fine. the only thing i changed from the previous 2 rides was a new air filter.

Any thoughts? Thanks.

Edited by marv02

Share this post


Link to post
Share on other sites

Two things: You replaced the air filter; be sure it's not over-oiled, effectively clogging it. Secondly, the plug can "look fine" but be glazed with a semi-conductive deposit that can short under a load. Try a fresh one.

Share this post


Link to post
Share on other sites

Also consider jetting issues if you test rode the bike on the street at lower elevation and in warmer weather.

Share this post


Link to post
Share on other sites

Check your jetting to make sure that all jets are clean, proper for your elevation, temperature(s), and any mods done to the bike. Follow the stickies in the forums to tune each circuit. Do not assume that the previous owner did the job properly. It also sounds like you should check on the accelerator pump diaphragm and do the O-ring mod. In my experience, the O-ring mod was much, much better than the BK mod and a hell of a lot easier.

Edited by Pooley

Share this post


Link to post
Share on other sites

Thanks for the replies fellas. Put in a new plug and that cured the mid range issue. Then found out the fuel screw was set fat for our altitude, turned it to 1 turn out and that fixed the 1/8-1/4 throttle hiccup. That was probably what caused the fouled plug as well.

More info on the o-ring mod please.

Thanks again.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now
Sign in to follow this  
Followers 0