Author Topic: clutch springs and cups  (Read 277 times)

Online berger

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clutch springs and cups
« on: 18.05. 2020 22:46 »
I fitted a second hand 4 spring clutch from a box of bits thinking I have it put together as it should be but, I backed the springs off one turn because it wasn't disengaging to well and a bit clunky. now it is biting at the end of the lever travel and I can't get used to it, cable and arm etc all set up well. so I need information. I don't know the part numbers of the springs and cups I have put in so can anyone tell me the length of springs part number 42-3273 and if these springs are the same as 68-3287 that I have seen for sale for the 4 spring clutch. also the length of cups 42-3197, I have ordered some new plates because I am thinking if the cups and springs measure up it could be the tired old plates giving me this problem. my 6 spring worked very well. --apart from giving the hand a good work out it started biting well before this one and never slipped or clunked. this triumph one is the hub without the rubber shocker, as columbo used to say "just one more thing" can anyone tell me the number of the clutch sprocket drum that goes with the rubber cushioned inner drum because I think I have a mash of bits that don't match all together if you know what I mean and I think the sprocket drum I am using with the hollow inner drum starts with 57,   I hope someone knows because I am very confused now *conf2*

Offline ironhead

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Re: clutch springs and cups
« Reply #1 on: 18.05. 2020 22:58 »
Can't help with the springs & cups but the drum & sprocket is the same for both. The 57'  is a triumph number.   ie Triumph clutch.
SA

Online berger

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Re: clutch springs and cups
« Reply #2 on: 18.05. 2020 23:30 »
iron head cheers fast reply, the number is triumph but there is a 42 sprocket drum as well so I need to know which part numbers go with which and those measurements . I am also needing to know why I have seen the 68 part number springs for the 4 spring early clutch, it is a headache at the  *pull hair out* edit---- o lordy just been on dragonfly site and seen 4 or 5 plate set up how the eck do I know what fits what now, I need measurements of all things that build up a 4 plate and a 5 plate, do they use the same inner and outer drums and just swap the springs and cups???? now I see fog!!!!

Offline Peter in Aus

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Re: clutch springs and cups
« Reply #3 on: 19.05. 2020 00:47 »
Time to go to the pub *eek* *beer*

Busselton West Australia
49 A7 longstroke
58 A10  SA

Offline ironhead

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Re: clutch springs and cups
« Reply #4 on: 19.05. 2020 06:40 »
G'day Berger.
Clear as mud *eek*.  I don't think drags has got it quite rite with the 68-3287 springs, these are for  late A65 , 3 spring clutches. The 68 number you mentioned for the early drum is for the early  4 spring A65's ( they mixed that up as well)
According to there list and another I've looked at & as you have found, you need the 42-3273 springs & 42-3197 cups. ( for 5 plates )
I don't know the dimensions though but they do mention the 42-3273 spring can be used on the small unit Triumphs with the  3 spring clutch ( lighter than the 750's).

How many clutch plates can you stack onto your clutch center ? ( has it still got the lip) you should be able to fit 6x plain & 5x bonded . ( there should be enough room to fit 1 more plain plate so as when the pressure plate is lifted the last plate can't fall off).

I've only ever seen 43t sprockets BSA number 42-3266 & Triumph equivilent.  They work with both center types.

You need to have a 5/6 plate set up, Ignore all the guff about 4 plates ( early pre unit triumph? C15/B40? )

With the spring cups fitted in the pressure plate do they bottom out on the backing plate?
If all 4 cups are the same length ( & clear the backing plate)
All 4 springs are the same length ( don't coil bind) You should get a workable clutch if all the other bits are up to scratch. ( any grooves in the drum from the drive plates ? )

If only we could just pop down to our nearest BSA dealer & buy the correct genuine parts instead of ( it might fit pattern parts/rubbish ) *rant*


SA

Offline Jules

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Re: clutch springs and cups
« Reply #5 on: 19.05. 2020 07:59 »
Hi Berger, out of interest why did you abandon the 6 spring if it worked ok? or was it just becoming too heavy/clumsy??
I have no knowledge of clutch differences I'm afraid, I'm just working with the bits I've got, but on another post, I asked about cables with Teflon liners (lower friction), what cable are you using and have you ever looked into that side of the "heavy 6 spring clutch"?? cheers

Online Sav

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Re: clutch springs and cups
« Reply #6 on: 19.05. 2020 09:47 »
Did a total guts refurb on my A10SR 4 spring hollow clutch start of this year and used SRM parts, plates springs etc. Every thing fitted fine and worked much better than before.
1961 A10SR, spent a fortune at SRM
1961 A7SS, finally the right green
2011 New addition 1937 Empire Star, twin port, high pipes. Turned out to be the most unreliable bike I have handled.
2017 finally found the liner/barrel were flexing and causing all the overheating/nipping up. Early B33 barrel fitted and it's reliable at last!
White Cliffs Country

Online berger

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Re: clutch springs and cups
« Reply #7 on: 19.05. 2020 12:02 »
first of all jules the six spring was set up for the way I ride not wanting slip when I give it wrist twist at 5000 plus rpm and to do this and enable easy stationary first gear selection it is a clutch that enables you to break brazil nuts between finger and thumb, also the two cables I have on the bike-one as spare are good cables. when I fitted the rrt2 I thought I would put together the 4 spring with parts that came to me. peter in oz, good plan and I am thinking the same *beer*. iron head your input is valued as for the numbers being wrong so it looks like I have ordered the wrong springs *doh* yes to it has the lip and I have 6 plain and 5 friction starting with a plain and finishing with one and they don't fall off. I did double up the last plain when fiddling about and yes that one would fall off. I checked the cups didn't bottom in the drum and as memory serves there was maybe 1/4 inch clearance. the cups are maybe about 1/3/4s inch and the springs are about 48mm 1/7/8ths these of course are old used items. there is also a rubber cushed inner drum and one cup that is 36mm about 1/13/32 and it looks like this one cup fits this drum *dunno*, there is also two springs at 43mm 1/11/16ths also old springs, I think the chainwheel is stamped 57-something and I got these parts after a mate was struggling with his clutch on a triton and fitted the 750 clutch, looks like I will be taking it to bits anyway when the new friction plates come and will see the number on the chainwheel that starts 57 and seeing if that is the same as the 42 one but then  having the lip inner that shouldn't matter should it? when do the pubs open *pull hair out*

Offline Seabee

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Re: clutch springs and cups
« Reply #8 on: 19.05. 2020 16:25 »
When you get it all sorted Berger, please post all of the correct #'s. I have a 6 spring on my RR and you do not want to get caught in stop and go traffic! I have a strong grip, but wow! If I back off on the springs to make it a little more tolerable, it slips. It is currently as "soft" (HaHa) as I can adjust it without it slipping.
I have a 4 spring in the SR and it is smooth and easy to operate. Luckily, the RR is my "show" bike, so it gets ridden very little. The SR is a jump on it, one kick, and GO! Very reliable and easy bike to ride. I completely restored both bikes, so I know all of the clutch internals are in good shape.
1961 Super Rocket
1957 Road Rocket
2009 Harley Electra Glide Classic
1993 Harley Springer Softtail
1971 Harley Shovelhead
1970 Harley Sportster Chopper
1957 Harley Panhead Chopper
1982 Yamaha XT550
2001 KTM EXC 400
1970 Honda CT70
Southern Illinois, USA

Online berger

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Re: clutch springs and cups
« Reply #9 on: 19.05. 2020 22:39 »
Seabee I have done some detectorist work on the interwebby, as far as I can make out looking at piccies I have the correct bits so will see what happens with new friction plates. chainwheel 57-1549 and that now rings a bell, springs 57-0999 and they look the same as in my clutch, cups 57-1931 also looking good, these numbers are for the 5 friction and 6 plain plates and from what I can see you can use the non cush drum or the cush drum with the lips on, so long as they are for the 5 friction plate clutch, err this is providing the numbers are correct