SFC1000 Starter Clutch

levo said:
I still have the Howdi starter in my Rgs .The original GM gearbox component certainly was a failure , it has chewed up quite a few alternators on my  Lav but I don't give up very easily. With a little bit of help from a friendly lady in an auto transmission place  we managed to find another GM sprag . The original one held the sprags in-between 2 rings where as the revised one has another slightly smaller 2 rings as extra support . I have been running this new sprag  for over three and a half years ,was just before my argument with that pesky Commodore which ironically probably had that early sprag in it .I have pulled it out to check it on several occasions and looks as good as the day I put it in so am  pretty chuffed.  The part no is T700r4 and is also out of  a GM auto transmission. 


Hey Levo - interested to learn a little.  So my howdi clutch does the job, has a bit of a rattle immediately after starting but otherwise the only surprise is the one I got when I found it in there.  Did you have any early warning before the earlier models failed?  And if you can get hold of the correct part number which has provided a reliable alternative I'd appreciate it.


Cheers, Nick
 
Nick Alcocks two triples with the Howdi clutch both failed and he revereted to stock, Howdi refunded the money, which was  hugely honourable thing to do, and unusual!, but didn't want the scrap back, Nick also did huge mileage in his bikes commuting 200 miles per day for decades, but the Howdi clutch mileage was not very high at all, the sprag bearing is not a GM part but a standard bearing part, he has the GM part number but they take double what a bearing factor will take, there is no point, in a Laverda triple it does not get sufficient oil, very odd how Levo's one works so well, Howdi did say he was using cast off parts from used transmissions and also new Chinese built bearings, but who cares anyway the stock stuff works just fine, I have two engines rotating in and out of TOG (and a third if you include the race motor) and always used the same stock starter clutch, yes it has had a few parts in it now and then, but never failed when in use.
CLEM
 
Hey Nick The only warning you get is if you inspect the sprag periodically by removing the alternator cover and if there are bits of fine metal filings stuck to the magnet the sprag is starting to fail or the alternator stops working cause the filings have damaged it.
As for the sprag its self the old sprag DID come from a GM auto gear box model as Clem said  T700r4but forget about that one. The revised sprag part no JXS70020 ALSO came from a GM auto trans model no 4L60E Now maybe the one you have may have a different sprag as Clem says from a bearing supplier but the double row sprag in mine as I said is still doing strong.
 

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Nick the first photo in my last post in the auto trans is the one you want notice the double ring holding the sprag together as compared with the bare sprag in the second photo which is the old one that fails. ps not sure what makes the rattle  in yours after startup as mine doesn't. Hope this helps.
Levo
 

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levo said:
Nick the first photo in my last post in the auto trans is the one you want notice the double ring holding the sprag together as compared with the bare sprag in the second photo which is the old one that fails. ps not sure what makes the rattle  in yours after startup as mine doesn't. Hope this helps.
Levo


Hey Levo - that is helpful - thanks.  Mine looks pretty clean at the moment so I'll put it back and look at finding the alternative part you quoted as well.


Cheers, Nick


PS. That is one strong RGS you have been riding - and well looked after  (congrats)
 
Cheers Nick glad I could help......yea the old girl still goes pretty well considering the way I have abused her.
Levo
 

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So when I put the clutch and alternator back I am planning on using the rattle gun to do up the alternator rotor retaining bolt, that goes into the end of the crank - this was my approach on the 1200TS.  I note there is no woodruff key like the 1200, or similar, on the SFC to avoid any slip, and wanted to check with that there is no special instruction for the SFC? There is also a lock washer on the 1200, but not on the SFC.  (dunno)


Cheers, Nick
 
Nick I normally just do the nut up with a half inch drive ratchet and then give the ratchet a couple of belts with a rubber hammer seems to do the trick has never come undone until you want it too. Seeing that it is a taper fit I don't think it needs to be as tight as a rattle gun would make it but I could be wrong.
Levo
 
ngiles said:
So when I put the clutch and alternator back I am planning on using the rattle gun to do up the alternator rotor retaining bolt, that goes into the end of the crank - this was my approach on the 1200TS.  I note there is no woodruff key like the 1200, or similar, on the SFC to avoid any slip, and wanted to check with that there is no special instruction for the SFC? There is also a lock washer on the 1200, but not on the SFC.  (dunno)


Cheers, Nick

That is because the MkII/120? alternator is not timed for anything, absolutely irrelevant how it is fitted.  A key will not stop it from slipping if the taper isn't tight, these are for locating only.  The key would need to be a lot beefier if it were to transfer any torque.

Apply a drop of Loctite medium to the screw, but careful with the rattle gun!  I've found quite a few stretched bolts... ::)

piet
 
I recently learnt the limits of the rattle gun whilst re-assembling the outer flywheel on my Falcone. Tapered crank end with a key.
The rattle gun sheared the key since I hadn't sufficiently tightened the nut first.
The flywheel fell off after 10 minutes.

I started again without the rattle gun and all's well.

Paul
 
sfcpiet said:
A key will not stop it from slipping if the taper isn't tight, these are for locating only.  The key would need to be a lot beefier if it were to transfer any torque. 

Learnt that the Hard Way many moons ago with a Ducrappi 860 ...  :(
 
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