Exup valve not cycling.

Purity Vendetta · Post by **Purity Vendetta** » Sun Oct 11, 2020 3:19 am

Hi all, I haven't been on here for quite some time, long story but I'm determined to get my FZR1000RU back on the road next summer. I'm in the process of 'recommissioning' the bike and have noticed that the exup valve no longer cycles through when the ingition is turned on. The valve appears to work otherwise. Anyone have any ideas? I'm thinking perhaps an issue with the CDI unit as it seems to control the valve. Given the tendency for them to seize up I want it to do the whole cycle like it used to.

Post by **Stig** » Sun Oct 11, 2020 8:27 am

Basics first...
Remove cables from 1 end so you can check individual Checking servo is working

Turn servo pulley wheel full in one direction. Then turn ignition power on and pulley wheel should reset to centre. Try other direction. If both self centre then servo is good.
There are plastic teeth inside the servo that sheer when the valve seizes. Some folk have swapped the gear over 180 degrees and successfully used the other unused area of the gear wheel. Also R1 gears are rumoured to fit

Then check if valve itself is free to rotate by moving pulley wheel by hand

Purity Vendetta · Post by **Purity Vendetta** » Mon Oct 19, 2020 2:15 am

Hi Stig, yes I went through all the normal checks, valve and cables free. The servo recentres when the ignition is switched on. I've come to the conclusion that it's a fault in the CDI unit as that controls the servo. I might try to borrow one to confirm my suspicions. The weird thing is that the system seems to be working re the revs.
Hope you're keeping okay in these strange times and thanks for the reply.

itsnotagenesis · Post by **itsnotagenesis** » Thu Oct 22, 2020 8:10 pm

You may be looking for a problem that isnt there. Not all servos cycle when switching on the ignition.