Starter clutch (Not again!)

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grubby
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Joined: Wed May 01, 2013 8:05 pm

Starter clutch (Not again!)

Post by grubby »

I know this subject has been done to death, unfortunately that's part of the problem. There's so many posts about it that although I've been trawling for an hour I haven't found an answer that I need. So please bear with me.
My starter clutch didn't work when I got the bike so the first thing I did was to get access to it and take it apart. On the inside of the mechanism the "Triangular" metal plate has got worn by the rollers and I suspect that this is the reason why it's fritzed. My question is how does one fix this or does anyone know where I can get a new starter clutch?
https://photos.app.goo.gl/vmNzTKhqaGunz5rr6
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slosher
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Location: Walsall,Black Country

Re: Starter clutch (Not again!)

Post by slosher »

Hi Kevin if i were you i'd Bin It and try to find the later starter clutch Borg Warner ;)

Cheers Dave
GT750L
GT550L
TL1000 97s
T140V
Loctite Trained Engineer :lol:(since having the Bonnie)
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Alan H
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Joined: Fri Aug 05, 2011 6:38 am
Location: Wombwell, Republic of South Yorkshire

Re: Starter clutch (Not again!)

Post by Alan H »

Just keep looking. These early clutches are very hard to find nowadays.
I sold my last one last week.
The main wearing part is the centre which the three rollers run on. If that is damaged, it's knackered and there's no new ones available.
Or buy a complete late clutch with the borg warner starter clutch and change the lot.
Proof that four strokes are over complicated
quark77
Posts: 495
Joined: Tue Sep 26, 2017 10:27 pm

Re: Starter clutch (Not again!)

Post by quark77 »

theres an American outfit selling the pins, springs and rollers ,he says they are the same fit for the 550 and 750 ! Not sure about that
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Rich100
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Location: Doncaster

Re: Starter clutch (Not again!)

Post by Rich100 »

Hi Grubby,
I’m Going through the exact same problem and as Alan has said it’s the starter clutch Gear thats the problem if thats
Knackered you will have problems finding a replacement. My gear is just about repairable see picture.
194DB4D3-BD7A-4778-BA40-B777D692F0F3.jpeg
F5BD6FCC-4D3E-400F-82C6-87BEFEF4446D.jpeg
I have managed to track down the repairs kit in the UK and at a very reasonable price as it’s for the GT750 which uses the exact same part numbers and is therefore much cheaper than ones that are advertised as GT550 ones.
https://www.ebay.co.uk/itm/362543379547.

Hope this helps and you manage to fix it buddy.

Kind regards,

Rich.
Suzuki GT550 M 1974
Kawasaki Z650 1980 F1
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Alan H
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Location: Wombwell, Republic of South Yorkshire

Re: Starter clutch (Not again!)

Post by Alan H »

The GT750 (all models) and GT550 early models starter clutch rollers, collets, and springs are identical and same part numbers. Unfortunately all the rest is different.
The issue with the 550 one is that the 3 countersunk screws that hold the 'triangular' retaining plate come loose due to lack of maintenance and then the rollers 'chatter' on the centre as it all gets loose and then it's knackered. The rear 'driver' cog that meshes with the starter motor is no longer available, so if yours is pitted or broken, you're stuffed. I was told many years ago by Eddie Crooks and Frank Whiteway about this - and the cure - which should have been picked up during servicing, but hardly anyone bothered back then, so they mostly ended up in bits. The later Borg Warner style clutch centres (or a complete BW clutch) can be fitted, but they are getting rare now due to everyone with the early clutch fitting the later ones.
The cure? Completely dismantle the clutch (you can make a clutch holding tool out of an inner and outer clutch plates and a bit of scrap metal for a handle to get the centre nut off) and examine the thin large diameter gear at the back. This has a 'pigs nose' spigot that the 3 rollers run on and unless that is perfect, or can be machined perfect, it's boned.
If it's ok, then remove the 3 countersunk screws holding the triangular plate and clean the threads very well - studs and holes - check everything for wear.
Remantling. At Crooks, they told me to gently tap the stud threads to slightly 'bruise' a couple of threads, then apply loctite studlock the the threads and screw the studs in as tight as possible with a screwdriver. Then give each one a good \\\\\ (technical engineering term*) with an impact driver to be sure it's TAF (another tet*). Lastly, use a centre punch a couple of times on the outer edge of the 3 studs to make an indentation half on the stud and half on the triangular plate. The little bleeders won't come loose again. A set of rollers, collets and springs are thirty-odd quid from Francos or elsewhere (or Baz might have some), and I would recommend fitting new ones. When the job is all done, fill the gearbox with a decent 10w40 mineral oil and keep an eye on the level as the 3 rollers need lube or they'll eventually shatter and the saga starts again.
Proof that four strokes are over complicated
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grubby
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Re: Starter clutch (Not again!)

Post by grubby »

I've now sussed out what my problem is and it's a weird one, which is why I was so confused as to how the starter clutch could work in the first place. Bear with me here! :roll:
My starter gear centre, which is an interference press fit is no longer an interference press fit! :oops: So what has been happening is the starter gear is spinning on the centre piece which is why the clutch can't engage.
So does anyone have a spare starter gear? Or do I have to get a machine shop to weld the centre onto the gear?
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Alan H
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Re: Starter clutch (Not again!)

Post by Alan H »

That's the bit that is completely unobtainable. First, ensure the outer face of the centre of that part ( that the 3 rollers run on) is perfect. If it isn't it will cause the rollers to chatter on the face and eventually shatter, causing the roller(s) and centre to lock the clutch and probably do other damage.
If you still decide to get it welded, then it has to be done perfectly otherwise it will act as an eccentric with eventual failure as above.
Proof that four strokes are over complicated
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