How important is the exup valve on a 98 R1

[Sentry]

Have started disassembling the 98 R1 and found that the existing exup valve is no longer attached to the exup pulley (the two cables have been deleted). How important to the running of the bike is the exup valve? Is it advisable to reinstall the deleted cables? Cheers

[Arwon]

get rid of it, or lock it fully open. But you must keep the actuator connected electrically or by an EXUP eliminator. They are mainlt there for low revs and are fully open when at high revs. You will notice better throttle response down low after this fix.

[Sentry]

I was hoping you'd post. The actuator is still in the bike so I'll leave it connected. Thanks for answering!

[Arwon]

your welcome

[Sentry]

Turns out the exup valve has been deleted as well. Looks as though it came with aftermarket headers, possibly at the same time the Yoshimira exhaust was put on. Noice.

[Arwon]

Perfect, so the cables are there still. Just remove the tank and remove the cables and the jobs done. My 01 R1 has a full Yoshi system, it sounds great and it has better throttle response and power than a standard exhaust.

[guarino11]

Ive been looking through my 99 R1 and the exup motor is working but the valve is completely seized in a half open/closed position. Ive tried crc/WD 40 and some Loctite ‘Freeze and Release spray. Its not budging!

any suggestions on how to get it moving or is it best to scrap it and get a full system?

[Brendonv]

Anyway you can get a little 3 arm puller on it?

[guarino11]

Ive tried pulling at it with a pair of pliers but nothing. Would the 3 arm puller do a better job?

[Brendonv]

Not sure. Could you whack up a picture of what this thing looks like. Not sure if a puller could be used.

[Arwon]

Never had to free one up but a full system is the way to go. Download the workshop manual, it is freely available on the net.

[Brendonv]

Just had a look at the R1 EXUP valve. A puller wouldnt work. I was thinking of a different sort of valve. This is more like a throttle valve (on a small whipper snipper or something). My suggestion is to get some vice grips and extend the pivot arm with a pole or something and wriggle it back and forth to try brake the rust. The other option is to heat it. Once you do this, remove it and lightly sand the shaft so it doesnt seize again.

[guarino11]

This is with the pulleys still attached

This is them with it removed


I cant turn it and I cant pull it out.

Ive got my hands on the manual and although its a really good manual there's not much in there for this problem

[Sentry]

It may be some corrosion on the inside preventing the valve from moving. Try the vice grips first and spray CRC down the pipes.

[guarino11]

I started the bike up and let it heat up for a 5 mins and then tried to wriggle it out with the vice grips. I took the can off and sprayed down there aswell. Still no movement.