Sprag clutch... What Ive learned so far

[fatboy]

If you have starting issues get it sorted. It only takes a few weeks to kill the sprag !
If someone gives you a sensible price to do the job, bite their hand off, its not that cheap DIY.
If you have R&G bungs fitted no need to drain oil tank and remove, undo the return line from the oil cooler, the tank fits nicely on the rear bung.
Its taken over 3 hours just to get the flywheel off, broken 2 pullers, about an hour of blowtorch use, countless worries over stripping threads/shearing pullers ect.
So cost so far....
Loctite 648 £22
Internal puller, broken, repaired, broken. few beers
Workshop quality 2 leg puller £38( on offer )
Gasket and new flywheel retaining bolt £33.03
Sprag clutch £91
I went for an external puller in the end because I did not want to wreck the motor, never seen anything like this before, fucking nightmare, think Jay and Tim lucked out on their job

[fatboy]

Now relaxing with a beer,...and looking at said parts...
The length of the taper/interface between crank and flywheel is approx 40mm, about twice the norm.
That amount of contact surface area with Loctite 648.......
WHY ?

[blinkey501]

If you have starting issues get it sorted. It only takes a few weeks to kill the sprag !
If someone gives you a sensible price to do the job, bite their hand off, its not that cheap DIY.
If you have R&G bungs fitted no need to drain oil tank and remove, undo the return line from the oil cooler, the tank fits nicely on the rear bung.
Its taken over 3 hours just to get the flywheel off, broken 2 pullers, about an hour of blowtorch use, countless worries over stripping threads/shearing pullers ect.
So cost so far....
Loctite 648 £22
Internal puller, broken, repaired, broken. few beers
Workshop quality 2 leg puller £38( on offer )
Gasket and new flywheel retaining bolt £33.03
Sprag clutch £91
I went for an external puller in the end because I did not want to wreck the motor, never seen anything like this before, fucking nightmare, think Jay and Tim lucked out on their job

Glad it sorted mate.

[mangocrazy]

The length of the taper/interface between crank and flywheel is approx 40mm, about twice the norm.

The amount of gripping force that Loctite 648 can exert over a length of 40mm is insane. Obviously Aprilia never wanted it to come loose, intentionally or unintentionally.

Well done that man. How much heat did you have to apply to get the job done?

[fatboy]

I think I must have used the blowtorch for around an hour, on and off. When it did let go it went with a helluva crack, threw the flywheel against the retaining bolt, had to use stilson's to remove the bolt as the pressure point from the puller was embedded in the socket cap thing.
By ironic chance my mate turned up with a hardened internal puller today, delayed by ill health.
The puller IS available to borrow/copy ect. 2 way puller, internal tapping for a pusher bolt

[mangocrazy]

By ironic chance my mate turned up with a hardened internal puller today, delayed by ill health.

Fairly typical... Is that the glorified bolt that AF1 sell on their site - the official Aprilia tool?

The puller IS available to borrow/copy ect. 2 way puller, internal tapping for a pusher bolt

Any chance of a pic? Does this one have the correct internal thread, and two legs?

[fatboy]

Its 22mm x1.25 to fit the flywheel and butt up against the crank. The internal tapping looks like 12mm ( Falc crank is 16mm )
It was made to fit a universal puller set rather than a Falc. If the internal bolt were to shear it could be retrieved by magnet.
The internal bolt must be carbon steel so should cope ok...
Pics.. got to learn me how to use dropbox ect