EXUP question - YZF1000R

Alright so I have to lube the EXUP valve bushings on my '97 ThunderAce
with some anti-sieze every 5K miles or so - done it 5 or 6 times
already - no big deal - 30 minutes work and the squeaks are gone. This
time, however, I got interrupted in the middle of the job - phone rang,
one thing led to another - now a week later I can't remember which way
the power valve faces. Didn't realize it would fit either way until
last night when I tried to put it back together.

So help me out here Yamaha experts - which way does the concave side
face - toward the engine or toward the rear? Also, can't remember
which cable goes toward the front so can you tell me which way the
valve is supposed to rotate - CW or CCW?

Thanks!

 

It should be obvious. Which way are the hot exhaust gases coming from?
Rounded side to the front.

When you manually turn the servo motor pulley all the way clockwise,
and then turn the ignition switch on, the servo motor will return to
the digitally-computed running position for the RPM it's turning (zero
RPM while you're working on the valve) so you should be able to see
which cable will turn the lower pulley the same direction when you
manually rotate the upper pulley.

Since I have no corrosion problems here in Calfornia, I have only
adjusted the cables
once.

 

Ding ding ding you are correct sir! I got resourceful and checked out
the schematic on BikeBandit
(http://www.bikebandit.com/partsbandit/showschematic~dept_id~401653.asp)
and the convex side goes toward the front. And you're right - should
have been obvious - not so much from a curvature standpoint because it
would cork up the works either way but rather, placing the flow
restriction upstream of the bushings keeps the bushings from being
overly pressurized - less leakage of hot exhaust gasses and carbonizing
that way. But for some reason things aren't as obvious at midnight
after a long day as thay are after morning coffee...

Yeah I was kind of hoping not to have to take the tank off. Oh well -
it's probably about time to adjust the cable tension anyway. Hey
thanks for your quick reply!!!

 

Service manual for the above bike can be downloaded from
http://thunderace.hadeler.net/service_manual/
or
http://www.blackbears.ru/manual/files/Yamaha_YZF1000RJ(RJC)_Service_Manual.zip

 

SWEET!!! Thanks for that info, Daron!