SFC1000 sprag clutch

A

andre

Senior member
Guys
At 99,859 km my SFC1000 starter clutch is getting a freshen up (springs, plungers, rollers).

The 'freewheel' that the rollers contact onto surface is a little worn (dented or 'chattered'?).

I can leave as is, get the surface ground smoother, or get it metal sprayed and ground back to correct dia (what dia?)?

Advice on best option please?

Thanks
Andre
 
If it's working leave it well enough alone.  This surface is very highly loaded and just about every attempt to repair them that I have seen has failed.  Newly manufactured replacements even suffer and one I had only lasted a short time.
Just put in the new rollers etc and button it back up, deal with the freewheel if it starts to give you trouble.
Cheers
SteveB
 
leave it, you are asking for trouble if you play with it

if you grind it smooth you are reducing the diameter and when they get too small in diameter the clutch stops working as the rollers only have limited movement

if you build it up with metal spray the built on material will be totally torn off within the first couple of attempts at starting the engine

as Steve said, that is a very highly loaded part

 
Thanks Steve and Red. Ties in with my recollection of old posts on this subject. I'll get on with reassembly tomorrow.
Off to watch sprintcars at Western Springs Speedway. Yahoo

Another minor thing. Clutch drum off while I install new primary chains. I'm sick of those anti rattle springs on the plates so I'm gonna bin them. Any disagreements to me binning those 2 springs?
 
andre said:
I'm sick of those anti rattle springs on the plates so I'm gonna bin them. Any disagreements to me binning those 2 springs?
Click to expand...

no disagreement from me, is a fine plan

others will be along soon to disagree though

 
Glad we agree on that.

Back to starter clutch. How the hell do I hold those new springs/plungers/rollers in place while I install the freewheel. Its driving me (more) nuts
 
Assemble the gear wheel on to the sprag unit off the bike...a simple anti-clockwise (from memory, but it's easy to work out by observation) twist works against the rollers, compresses the plungers & springs so that the gear wheel shoulder just slips into position.  (This is done with both components horizontal so nothing falls out of place).  Then offer the whole assembly up to the bike's crankshaft.
 
Further to Rob's advice - with the alternator laying on the bench and all springs/rollers installed, it's possible (provided you don't have too big/clumsy fingers) to reach in and push each roller back one at a time to get the freewheel in.  Careful of the sheetmetal edge on the roller sideplate - usually very sharp!
Cheers
SteveB
 
I assemble the rollers with a dab of grease which helps hold them in place better
grease gets diluted with the oil over time and disappears
 
redax5 said:
no disagreement from me, is a fine plan

others will be along soon to disagree though
Click to expand...
I don't disagree but I agree, you can get rid of the anti-rattle springs without any undue side affects. With great trepidation, I ditched mine a couple of years ago, can't say it made much difference to the clutch operation but certainly made life easier. If you can get hold of one, suggest you whack in an extra steel plate between the two friction plates that had the springs attached.

As Red said, somebody will be along soon to disagree :D :D

Terry
 
Had those springs fitted to the S1 80 mirage in the Motodd. Ditched them 60k kays and 13 years ago. Made absolutely no difference that I'm aware off. Also fitted an extra friction plate too.
 
Got sprag clutch sorted thanks Guys. Wasnt that hard once I applied myself (got someone else to do it...)

Regarding extra plate in clutch housing (got rid of anti rattle springs) - will anextra steel plate create any issue over pressure plate having less 'depth of engagement' where it engages with the clutch hub teeth?
I guess I could draw a picture if thats not clear
 
Know exactly what you mean Andre, suppose it depends on how worn your existing plates are. I would do a bit of experimenting, if the extra plate takes up too much space, you could always put it aside and whack it in when the plates have a bit more wear. HTH

Terry
 
Binned the springs when I fitted a new primary chain on the series 2, 
compared my fingers and the size of the springs mmmm, f$%# this! haven't noticed any difference.
maybe a bit more rattly at start up, bugga all really, but when the clutch takes up its real quiet.
 
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