I am refitting the clutch on my '63 650 SS and am a little confused as to what type of clutch centre and chainwheel I have. The Haynes manual shows a clutch centre with bonded friction pads on the backplate and a chainwheel with a solid backplate. My centre backplate is solid with no friction material and the chainwheel has a perforated backplate into which loose friction pads are inserted (pics attached). The Andover Norton and Norvil websites show a solid chainwheel with friction material on the clutch centre backplate. RGM show both a solid chainwheel and one with a continuous friction pad together with a plain clutch centre. They say these latter two parts are for early 3 spring clutches which I presume is what I have. No one appears to show a chainwheel with perforations and loose inserts like mine. My clutch was on the bike when I bought it in the early 1970s, but I don't know if it might have been modified before that. It worked perfectly well until I stopped using the bike in the 1980s. However, it would be helpful to know what setup I have if I need to replace any b its during assembly. Has anyone come across a chainwheel like mine before?
It's the early clutch. Used…
- Log in to post comments
clutch
hello i dont know how in GB but in Czech republic is possible to make repas of this part but it is not cheap
about 70L
it makes firm forexample
https://www.renovak.cz/spojky-pro-historicke-motocykly
i have on 650 ss late tipe of clutch there are two variants of springs and my clutch have more plates than earlier clutch
- Log in to post comments
I believe the correct clutch…
I believe the correct clutch had a thinner pressure plate and more plates to handle the power of the 650.. If the clutch is handling the power then I would not worry.
- Log in to post comments
More dominator clutch problems
I am proceeding with the rebuild of my 650SS clutch but am having problems putting it back together. The clutch spring stud nuts, part 040356 are not screwing onto the clutch spring studs, part 040384. When previously installed the tops of the studs had been peened to lock the nuts. Whilst the nuts undid OK, the top of the thread has been distorted making the nuts difficult to engage with the thread when tightening back up. I could simply replace them but apart from the top of the thread the studs are in good condition. and I would like to keep as many of the original parts as possible. I have tried cleaning up the threads but neither a Whitworth nor BSF die fits. I suspect that they are a 1/4 or 5/16" BSC thread but I don't have any BSC dies. Does anyone know the correct thread for this stud? It is the short, threaded section that fixes into the clutch centre and not the longer portion which holds the clutch springs.
- Log in to post comments
I think you are right about…
I think you are right about the thread being BSC , but being so short will be dificult to clear the stud threads with a thead die. The nut thread should clear with a tap. You could use locktite to secure instead of staking the nuts . You have to grind the face off a socket to get a good purchase on the nuts.
- Log in to post comments
Thanks Robert. It is only…
Thanks Robert. It is only the very top of the thread that is damaged, but I think I will grit my teeth and order some new ones. Helpful tips about the socket and Loctite.
- Log in to post comments
Allan - just run a junior…
Allan - just run a junior hacksaw blade around the thread working your way around and across the damaged few threads at the end of the stud. Remember that the flats on the stud have to engage with the flats on the race plate and should protrude a few threads after the end plate is in position. The shouldered 5/16 inch nuts should then engage. I use the 5/16 inch box spanner, that Norton recommend for the front cylinder head nuts, to tighten these three nuts and locktite. The stud should be flush with the top edge of the nut when fully tightened. Cheers, Howard
- Log in to post comments
It's the early clutch. Used from 1932 until the AMC box appeared. The later clutch has the friction and plain plates the other way round. Probably cheaper to machine the basket after the redesign. No disadvantage in use (unless someone knows differently?).