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EXUP valve problems

17K views 13 replies 8 participants last post by  hkdupz  
#1 ·
Can a messed up EXUP valve stop the bike from running?

The bike starts, while choked, but as soon as I hit the smallest amount of throttle, the engine dies.

I just got the bike back from a frame shop - it ran a week ago just fine. and they had disconnected the exup wires. I reconnected them, each possible way, but now the engine just dies.

Any help???
 
#4 ·
just because the cables are attached doesn't mean they are adjusted properly. They could be way outta wack. Do you have a manual that explains how too adjust them? Might sound simple but is your gas turned on under the tank. Maybe the shop turned it off before they removed the tank and forgot to turn it back on? Does your fuel pump prime when you turn the key on?
 
#5 ·
the only reason a code would be throw is if there was an sensor/servo motor issue. Take the cover off the exup (on the header) put 12volt to the servo motor for less than 1 second to see if it operates..Thats what the factory manual states.
 
#6 ·
Servo motor works. I had the tank off and turned on the ignition.

The bike starts, so it's getting fuel, and I double checked the gas lines. I took off the header and checked the exup valve, it turns as it should.

I think the trouble might be somewhere else. It just dies when I turn the gas, and it will only start with the choke.

It's probably some wire that I may have crimped putting her back together.

Trouble shooting continues.

Thanks for the suggestions!

-Bryce
 
#10 ·
My idle stay high at 3k RPM on my 02 R1. It does not kick donw until the bike reaches 220 degrees and fans turn on then it is normal. I did replce the header. How do you adjust the cables. Is there a choke cable that isnt kicked down?
 
#11 ·
On the 01 R1 there is a throttle advance screw located on the left side below the carbs. you can change you idle speed by turning the screw.

Did you check you choke? choke cable? a rich mixture would cause your idle to advance, but it might fowl your plugs quickly too if it's the choke
-Bryce
 
#12 ·
Hey guys, iv just reinstalled the exup on my 2000 R1, its lost alot of power from the a/m exhaust, (i wanted to experiance the bottom end power) i dont have a manual and was wondering if anyone can tell me how to adjust the exup cables encase they are out?