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More sprag quesstions - help needed!

A

A303

Didn't want to hijack Kiwi's thread so:
Symptoms (01 RSV) are graunching noise from motor when trying to start but not turning over fast enough to fire. Been doing it a while but would usually start fresh off the optimate with only subsequent restarts being marginal.
No won't start at all, even when jumped from car, just graunch, graunch, graunch.
3-week old, Bosch 14BS showing 12.5v (engine off), new Yam starter solenoid, cleaned battery, solenoid and starter terminals/cable ends, so I don't think it's electric related.
Would someone like to comment/confirm that it sounds like sprag?

Happy to go in and have a look but need to know where I can get the flywheel puller or if I can use a generic one?

Alternatively, is there anyone out there (not too far from the south!) who can quote me a price to do it?

I have to pay the balance for my track trip to Spain by tomorrow and I have to make a decision on whether it's practical to get the bike fixed in time to get it to the transport for the trip by 29 November.

Any help and advice appreciated. Thanks.
 
sounds definatley like the sprag if graunching sound from lower engine.

Might want to speak to Kiwi to see if you both can get together to do both bikes at the same time, perhaps can get discount on parts plus you wont need to buy 2 flywheel pullers.
2 heads are better than one .
 
sounds definatley like the sprag if graunching sound from lower engine.

Might want to speak to Kiwi to see if you both can get together to do both bikes at the same time, perhaps can get discount on parts plus you wont need to buy 2 flywheel pullers.
2 heads are better than one .

Could be a plan - Kiwi's a bit far away but would be good to swap tips.
Anyone got a puller that they could measure for me so I can order one of those pattern ones?
 
Could be a plan - Kiwi's a bit far away but would be good to swap tips.
Anyone got a puller that they could measure for me so I can order one of those pattern ones?

I haven't got a puller, but if you need any advise I'm here and sure Kiwi RSVR will give you some advice too.

We are both on MSN, PM me and I'll give you my details, easier to help on MSN.

Please stop trying to start it with a fragged sprag, you'll end up causing a lot of expensive damage.

I'm still not convinced those BMW sprags will fit.
 
Hi mate i had a puller made for mine its a 22mill thread by 1.5 so if you know a tool maker or can get a 22 mill bolt you can pull it off with that get a blow torch so you can heat it up for about 10 mins it not that hard to do it you are good with tools mate i just put a new spring in mine good luck mate:thumbup
 
Thanks Guys.
Ordered the BM part from Motorworks - explained exactly what I wanted it for and the guy said he'd take it back as long as I hadn't fitted it, just costing me postage. Got to be worth a shot at 60-odd quid eh?
 
Once they start graunching 99% of the time you will have scored the housing as well.
If you put a new clutch in a scored housing chances are it won't last all that long. Given the housing isn't mega expensive i would do both while your in there.
 
Totally agree with Spoonz here , mine is really quite bad and will be replaced.
Dont forget to check the diameter/condition of the sprag gear brass bush as well :)
 
Thanks for that.
Ordering housing today and will check all the other bits.
 
Thanks Guys.
Ordered the BM part from Motorworks - explained exactly what I wanted it for and the guy said he'd take it back as long as I hadn't fitted it, just costing me postage. Got to be worth a shot at 60-odd quid eh?


Sounds expensive to me on something your gonna use Once :eatcorn

Better off paying postage and a beer for a fellow zoner to send his to you.
 
Sounds expensive to me on something your gonna use Once :eatcorn

Better off paying postage and a beer for a fellow zoner to send his to you.

Tim, I reckon A303 is talking about the actual sprag clutch not the puller.

Those 22mm x 1.5 pitch pullers on Ebay may well prove man enough to do the job.
 
Can anyone tell me where I stick the crankshaft holding tool? (yeah yeah, apart form the obvious) Can't find it mentioned in the manual and it's not obvious.
 
Tempting though it is to give a different answer it goes in just behind the oil pressure sensor in place of a bolt which you must remove. It locks the engine with cylinder 2 at TDC so i would pop out the plugs so you can rotate the cranshaft untill it locates.
 
Well, flywheel is off and sprag bearing fell apart in my hands - that helical spring looks to be a weak point - the rollers didn't look too bad while the outer race is a bit scored but not too bad (replacing anyway). Micced up the brass bearing which is within tolerance.
Here's my question: what is the point of the spring clip? It obviously doesn't hold the sprag in place as that's trapped by the flange between the flywheel and housing.
The BM sprag I'm using does not have locating slots for the spring but it does have slots which correspond to the castellations on the spring which means it won't be latterally located. Any ideas?
 
Well, flywheel is off and sprag bearing fell apart in my hands - that helical spring looks to be a weak point - the rollers didn't look too bad while the outer race is a bit scored but not too bad (replacing anyway). Micced up the brass bearing which is within tolerance.
Here's my question: what is the point of the spring clip? It obviously doesn't hold the sprag in place as that's trapped by the flange between the flywheel and housing.
The BM sprag I'm using does not have locating slots for the spring but it does have slots which correspond to the castellations on the spring which means it won't be latterally located. Any ideas?

I take it you mean the large circlip that holds the sprag in to the housing?

It is designed merely to restrict lateral/torsional movement and ensure that when engagement of the sprag takes place the full load or stress is placed across the full face of the rollers.

Have you got a piccie of the BMW sprag so we can see what the design differences are?

Pretty sure that knowing BMW design engineers, it is most possibly a superior way of managing that spring retainer.
 
Thanks AMB. I'll take one this morning. Don't get too excited about the BMW engineering as it's from an F650 which, as we know, uses a Rotax engine.
 
Thanks AMB. I'll take one this morning. Don't get too excited about the BMW engineering as it's from an F650 which, as we know, uses a Rotax engine.

Was the BMW sprag much cheaper than the Aprilia one?

May be worth doing a case study on your sprags life span to see if the savings are worth it. For your sake I hope it is.

Did you manage to get a hold of some Loctite 648 for the assembly process?

PS. Don't forget to use some RTV on the seal on the top of the casing, otherwise it will leak oil, not much but it will make a mess of your nice clean bike.
 
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