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oh my fxxkin god my spragg clutch has gone

Joined Jul 2008
75 Posts | 0+
well after 3,000 trouble free miles my spragg clutch has given up the ghost.gulp.what i need is a step by step for idiots on how to replace this part.photos and diagrams any help at all.having read a few items on this problem it would appear you can use a bmw sprag clutch,alot cheaper by all accounts than a aprillia.reckon im gonna need the housing too as it sounds like a bag of spanners in a tumble dryer.any help will be rewarded with good khama and i think you,ll feel better having helped a fellow millle rider. mine is a 2000 very rare and the fastest electric blue type,although not the fastest today.what more can i add thanks for taking the time to read this. will use this thread to show the progress i have or have not made.
 
Here we go again - must be the winter.
Sorry to hear that mate. I've just put this lot (below) together for Whitetrash so it's all to hand.

First of all, how mechanically minded are you? It's not too much of a job if you know your way round a toolbox.

Secondly, CAN SOMEONE WHO KNOWS CONFIRM THAT THE 00 SPRAG IS THE SAME PART AS THE 01 -ON?

I think it is and if so, all of the below applies.


First off all – check this out:

http://www.apriliaforum.com/forums/showthread.php?t=155882
(With all the pics you need).

It’s most likely that the sprag and the housing are the damaged bits – the housing may look OK (just a few wear marks on mine) but it’s worth changing – unfortunately no one has yet found an alternative to the Aprilia part.
The sprag itself you can use the BM part –

http://www.motorworks.co.uk/bmw/products/product.php?f=b&bke=bmw&q=ENA57177&x=27&y=6


Part No. ENA57177

But you have to either fit it the ‘wrong way’ or rebuild it (simple but delicate job) so that the ‘balls’ lock the other way. You might find it a bit cheaper than from motorworks but they are reliable blokes and got it to me next day.
It’s about £58 quid plus postage – you can also use the Ducati sprag but it’s about £100 – don’t know whether the Ducati sprag runs the same way.

Aprilia Sprag - UK183
Ducati Sprag - UK100
BMW Sprag - UK55
Says Kiwi.


Notes:
Royton at REPS (http://www.repsmotorcycles.co.uk/) gave me the low-down on the BMW sprag.
If you assemble the sprag the way the Aprilia one comes out (with the flange trapped between the flywheel and outer housing) it will lock the wrong way (which I might have seen if I’d taken notice of the direction arrow on it!).
The BM part (and, Royston reckons, the Ducati part as well) has a smaller, tabbed flange which looks like it should fit in the milled recess on the back of the sprag housing.
Royston reckons he fits them the other way, with the tabbed flange between the large drive gear and the housing. He says he’s done several this way and at least one local bike he knows of is still starting strong three years later (the others he hasn't had back so ...).
To my relief, he also says that when he first used the BM part, he rebuilt the sprag to run the other way – just as I did – and it was fine.
The other query I had was the spring clip. The Aprilia part has small slots for the castellations on the clip to fit into: The BM part (and, according to Royston, the Ducati part also) just has gaps in the bearing cage, so gives no positive lateral location (you’ll understand what I’m on about if you see one). Royston says ‘it’s not going anywhere so don’t worry’ and he’s done enough of them to know.

I’m assuming that is a BMW part number (anyone confirm?) as opposed to a Motorworks one but anyway, it’s just a sprag clutch for a BMW F650 (circa 98, 99, Royston said, if you want to be specific).
You may find it even cheaper than this but I’ve dealt with Motorworks before (er, 1989 actually) and they’re top blokes – had this in stock and got it to me next day (think it was about 65 quid with postage).

For the housing and gasket, I tried the usual suspects who were very nice but quoted around 5-7 days from Aprilia – and we all know about Aprilia parts delivery times. So I phoned Speedaway Motorcycles www.speedaway.co.uk and they had both housing and gasket to me next day.

For the locking tool I used an M8 x 100mm plain bolt from my local engineering supplies place. The hole is in the r/h (as you sit on the bike) side just behind the oil pressure (?) switch at the bottom of the engine. The blanking bolt on mine was a gold allen headed bolt.
Get a socket on the flywheel then lay under the bike and ‘feel’ the bolt into the recess on the crankshaft.

You’ll need plenty of heat – about ten minutes with a blow torch on the centre boss until I saw the loctite start to drip out, then it should crack off with a breaker bar without too much trouble.

You’ll need Loctite 648 for the flywheel taper when you rebuild it – I bought a big bottle and it ain’t cheap so I might be able to decant enough into a smaller one if you want me to send you the tools. Let me know.

If you’re worried about using a non-Aprilia part, I did mine just before I went to Spain for four days of track abuse and it is fine (touchwood!).

Hope this helps.
 
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well after 3,000 trouble free miles my spragg clutch has given up the ghost.gulp.what i need is a step by step for idiots on how to replace this part.photos and diagrams any help at all.having read a few items on this problem it would appear you can use a bmw sprag clutch,alot cheaper by all accounts than a aprillia.reckon im gonna need the housing too as it sounds like a bag of spanners in a tumble dryer.any help will be rewarded with good khama and i think you,ll feel better having helped a fellow millle rider. mine is a 2000 very rare and the fastest electric blue type,although not the fastest today.what more can i add thanks for taking the time to read this. will use this thread to show the progress i have or have not made.

mine is in bits at the mo so any help you need feel free to ask!
 
well after 3,000 trouble free miles my spragg clutch has given up the ghost.gulp.what i need is a step by step for idiots on how to replace this part.photos and diagrams any help at all.having read a few items on this problem it would appear you can use a bmw sprag clutch,alot cheaper by all accounts than a aprillia.reckon im gonna need the housing too as it sounds like a bag of spanners in a tumble dryer.any help will be rewarded with good khama and i think you,ll feel better having helped a fellow millle rider. mine is a 2000 very rare and the fastest electric blue type,although not the fastest today.what more can i add thanks for taking the time to read this. will use this thread to show the progress i have or have not made.

Davos, sorry to hear your sprag woes.

A303 has compiled a pretty damn good how to there, if your still a little wary then use this for images and a bit of guidance - Click Me

Download the user guide after entering in the code at the top right of the screen. This code is just to make sure your not another computer.
 
ok,after hours of reserch im going to have a crack at it.wish me luck.reckon i burnt the solinoid out too, as it only turns over when i cross it with mr screw driver.as for mech minded,i,ll give anything a go.i can only make it worse or better.
 
ok,after hours of reserch im going to have a crack at it.wish me luck.reckon i burnt the solinoid out too, as it only turns over when i cross it with mr screw driver.as for mech minded,i,ll give anything a go.i can only make it worse or better.

As long as you follow the instructions and use the right tools this is a pretty easy task to complete.

If in doubt as to any part of it, please just ask.

Many guys on here have done these before and I'm sure they'll help you along the way. As will I.

You'll find getting the flywheel off is a ******* of a job, make sure you have a good heat source and a good puller.
 
Just gotta be patient with that flywheel - just sit there and heat it for around 10 minutes, she'll come.
Good luck mate. Any probs, just ask.
 
Davos. I'm just posting the puller and crank locking bolt to Whitetrash - if you can hang on, get in touch with him and ask him to post them on to you once he's finished.
 
just ordered housing and sprag bmw version.got everything else.just adapting bbq gas bottle to fit on my plumbers torch. could def do with puller,thought my puller kit would get it off but its not happening.not enough grip to edges.so would be truly gratfull for the lending of puller.unless you could give the dimentions of it,thread size ect.and i,ll buy one.
 
just ordered housing and sprag bmw version.got everything else.just adapting bbq gas bottle to fit on my plumbers torch. could def do with puller,thought my puller kit would get it off but its not happening.not enough grip to edges.so would be truly gratfull for the lending of puller.unless you could give the dimentions of it,thread size ect.and i,ll buy one.

Hi mate,

The puller dimensions are on this thread Click Me.

Pretty sure you can get them off Ebay for around £10 too.
 
Here's the bloke I bought it off -

http://stores.ebay.co.uk/Classic-Pre65-and-TY-Trials-Shop

It's a 22mm r/h thread.
Crank locking tool you can use an M8 by 100mm bolt. Make sure it's a good quality one - you DO NOT want it snapping off in your crankcase!

If Whitetrash finishes with the tools in time I'm more than happy for him to post them on to you, so get in touch and see how long he's going to be.
 
My heart goes out to all of you with sprag clutch problems, i'm praying i havn't bought a fragile bike, i know the triumphs have sprag probs as well.

Good luck to you all, i'm watching all the posts regarding this, and wish you all the best.
 
My heart goes out to all of you with sprag clutch problems, i'm praying i havn't bought a fragile bike, i know the triumphs have sprag probs as well.

Good luck to you all, i'm watching all the posts regarding this, and wish you all the best.
Mate, it's all down to how you start them - keep the battery in top shape, upgrade to a beefy one when you can and keep it on an Optimate, do the Yamaha relay mod and even the alternator wiring mods (it's all on here, just search) and then make a point of starting it with the cold start lever on and zero throttle. If it don't start, leave it! And get the battery well charged up before you try again.
Then your sprag should not give you any problems (hopefully!).
I know that some of the Triumphs you can do through the top case hatch - but on some of them, if the starter clutch goes it's a full crankcase split! So we're pretty lucky.
 
A303 all your help is much appreciated mate, as soon as i recieve the tools i will get it stripped fully and order what i need. think i will fit the relay as a matter of course as well. Its got new plugs and a strong spark on all 4... lets hope it fires straight into life once its back together
 
A303 all your help is much appreciated mate, as soon as i recieve the tools i will get it stripped fully and order what i need. think i will fit the relay as a matter of course as well. Its got new plugs and a strong spark on all 4... lets hope it fires straight into life once its back together

No problem mate. They went in the post tonight. I didn't put any Loctite in 'cos I couldn't find anything suitable to send it in and didn't want to miss the post office. You only need a small bottle.
 

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