ex up valve

mine is stuck open, i have a new motor coming but, the bike is meant to be getting powercomander fitted and set up
will this valve make a difernace?

should i wait till i get the vavle sorted before fitting PC?

but u never go over 60 mph

Hov' - where you getting the power commander fitted too ??

roystons (r.e.p.s.)

cearleon

http://www.repsmotorcycles.co.uk/

[yorkie_chris]

The EXUP valve opens at high revs, it's closed at low revs to give more midrange torque, so you can get away with a higher tuned motor for top-end power.

With it stuck open it will be fine for top end but will not give true details of midrange.

I would guess that the mixture will be set up fine for the mids dynoing it as-is. But you won't get a true idea of how well it's going to run when the valve works. Depending on the FI's level of stupidity it may run rich in the midrange when the valve works again.

I would definately recommend that you get it sorted first, dyno time is expensive and doing it twice is silly.

Originally Posted by yorkie_chris

The EXUP valve opens at high revs, it's closed at low revs to give more midrange torque, so you can get away with a higher tuned motor for top-end power.

With it stuck open it will be fine for top end but will not give true details of midrange.

I would guess that the mixture will be set up fine for the mids dynoing it as-is. But you won't get a true idea of how well it's going to run when the valve works. Depending on the FI's level of stupidity it may run rich in the midrange when the valve works again.

I would definately recommend that you get it sorted first, dyno time is expensive and doing it twice is silly.

thats what i was kind of thinking.......

cheers

[yorkie_chris]

Originally Posted by hovis

thats what i was kind of thinking.......

cheers

EXUP valves are almost always in places hit with road spray, exposed to dirty exhaust gases. A bit of attention with a wire brush should see it right.

Originally Posted by yorkie_chris

EXUP valves are almost always in places hit with road spray, exposed to dirty exhaust gases. A bit of attention with a wire brush should see it right.

+ 1, don't go to a dealer and say its the EXUP valve as thats a Yamaha term!

[yorkie_chris]

Yeah yeah yeah....

allthat time looking for "the right Blade" and he buys a dog