05 cr250 variable altitude flap?

[ktgraf]

Just got a new 05 cr250. I read it has something called a "variable altitude flap". Anybody know what this does/how it works?

 

[john stu]

ummmmmmmmmmmmmmmmmmm what?!! do you mean the exhause flap ....it has nothing to do with altitude just exhaust pressure

 

[rosscopeeko]

I've got the Nov. edition of Dirbike mag and they state something weird in there about a traction control. They state it has traction control in the ignition black box that is designed to sense wheelspin and soften power accordingly. Is this true? It doesn't say anything about the variable altitude flap and notes it's extremely picky when it comes to jetting and altitude and tempurature jettings due partially to high compression.

 

[SQUIRLEYMOFO]

Just got a new 05 cr250. I read it has something called a "variable altitude flap". Anybody know what this does/how it works?

that's what it's called allright. Do a search on here there is a preferred way to set it.

 

[ktgraf]

from what I can now tell, it's the RC valve. I saw a link about it somewhere and it could have been a foreign so maybe something was lost in the translation. Apparently someone figured out if you adjust it differently than the factory setting it runs better, I saw a dyno graph and I believe it showed about 2 hp across. 12mm was the new recommended clearance (basically 12mm of rear cable showing). I'll worry about that adjustment when the bike stops scaring the **** out of me. Thanks for all the help.