Aprilia RSV4 Shift Spring Install

If this intimidates, you.....

Slowly step back away from the 1/2 air impact wrench......

This is what stuff you take off.
(covers, water pump, etc)

and you need.....

1. Aprilia Shop Manual
(for "stuff")
2. New Aprilia clutch cover gasket, water pump gasket (not supplied)
(you have 90% probability you can reuse originals, but I'm not that lucky?)

3. Normal mechanic's tools

4. 5mm allen wrench

5!!!  1/2" Impact wrench
(for 32mm clutch nut)

6. std depth 27mm socket

7. new clutch cover gasket

Remove the clutch cover and secure out of the way.

Careful, the starter idle gear usually falls out.
Carefully remove the 6 5mm headed clutch allen screws.

Sometimes the steel bolt "post" unscrews with the clutch screw - No matter, you can take the post and screw apart later and loctite the post into the clutch hub.
Remove the outer pressure plate.

Note the staggered semi-circles on the clutch tabs.

Keep that relationship (look at the Aprilia Service manual).

I'm sure there's some magic in the setup but it appears that every 2 change. Or there's an snickering engineer overseas who likes red herrings.
Now, remove the 27mm clutch nut. It's "normal" thread. Be sure to "unstake" the nut flange (if yours is staked).

Under the nut is a thrust washer (check that in the manual, I'm doing this from memory) and the slipper clutch 3 legged spring.

You can see, at 7 o'clock,  that one of our "clutch spring posts" unscrewed with the clutch screw.
Set the new Factory Pro Shift STAR in place - using that screwdriver to keep the detent arm down while you place the STAR into it's "only fits one way" slot -

When roughly in place, thread in the retaining screw in and rotate the Shift STAR until you feel it drop into it's shift drum slot.
It doesn't have to be in any particular gear position.
(in case you were wondering)

Rotate the shift star till it reaches the end of it's travel (it will be 1st or 6th).
Note that the stock detent arm doesn't need to be installed while you are installing the Shift STAR.

Good idea to use a drop of LocTite - but not absolutely required if you actually tighten the screw properly.
(6-8ftlbs torque).

Now let's install the new Factory Pro Microbearing Detent Arm.

Best to assemble the stack of shims, arm and spring onto the screw and thread the screw in just enough to hold things and lever the arm up, onto the profile of the STAR.

This picture shows what notch happens to be neutral. It's the 1/2 depth "valley".

LocTite is fine. 6-8 ftlbs torque

Check that the bike shifts through all the gears.
If it doesn't shift through all the gears, something's not aligned.

Click here to view a trained professional do it.

"Rotax transmission gear change Wild Ride!"

He happens to be shifting with the shifter, but I would leave the ZipTie on, and use the 5mm allen screw in the Shift STAR to turn the shift drum to check STAR / drum indexing.

All OK? Snip that ZipTie and let the shift arm finger reach over and caress the Star's pins.

Now, do like the movie star mechanic did - Reach under or over the bike and use the shift lever to make the changes.

This checks the shift arm operation.

All OK?

Put all the rest of this stuff back on.

Definitely use LocTite on the clutch nut and torque to factory Aprilia specs.


Aprilia Shop Manual
is the
Last Word
in assembly procedures!

If in doubt at all - do what your manual says.

Do all safety checks necessary. Test ride carefully!

Any problems? Call 800 869-0497 ask for Tech

Enjoy your new sweet shifting!

Marc Salvisberg

comments / corrections / additions?



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