The BSA A7-A10 Forum

Technical => Clutch, Primary, Gearbox => Topic started by: Guy Wilson on 06.10. 2017 16:36

Title: Stiff clutch lever
Post by: Guy Wilson on 06.10. 2017 16:36
Just how stiff is acceptable for a clutch?
My '53 Golden Flash has a later 4 spring clutch. The amount of strength required to pull the clutch in seems excessive and the clutch doesn't snap back when released.....Its ridable and the clutch engages and disengages as it should, although my left hand feels like its at the gym....
The cable is good and there's no resistance or frayed wires etc.  I've replaced the clutch rod as the previously one was marginally  tight in the tube. The replacement has no resistance between the activating lever and the clutch but makes no difference to the action.  The resistance seems to be in the springs on the clutch housing. Its possible I have the wrong springs, but they seem to be original although the bike came to me originally in bits and the clutch is from a later A10.
Has anyone else had  similar issues?  My Triumph TR6 by comparison has a very light clutch..
Many thanks
Guy
Kenya
Title: Re: Stiff clutch lever
Post by: duTch on 06.10. 2017 16:52

 Does the hand lever pivot easily without the cable attached? Maybe the screw/bolt  lock-nut is too tight ?
Title: Re: Stiff clutch lever
Post by: a101960 on 06.10. 2017 17:07
Yes, I agree with duTch, first thing to check is the handle bar lever. It is probably binding at the pivot point because it is to tight.
Title: Re: Stiff clutch lever
Post by: Guy Wilson on 06.10. 2017 17:16
I'll check the lever although the resistance appears to be at the clutch end.. stay tuned...
Guy
Title: Re: Stiff clutch lever
Post by: JulianS on 06.10. 2017 17:44
Check clutch cable condition, run and lubrication.

is your bike a very early swinging arm model or has the later 4 spring clutch been adapted to fit a plunger model?
Title: Re: Stiff clutch lever
Post by: t20racerman on 06.10. 2017 18:53
Agree with JulianS - amazing how much difference a correctly routed, good condition cable makes. My 4 spring clutch was a light two-finger only job.

Other checks - bent push rod, and adjustment of the cable so that the lever arm on the gearbox acts across a small range at 90 degrees to the cable.
Title: Re: Stiff clutch lever
Post by: muskrat on 06.10. 2017 21:06
Also check the adjuster inside under the oval cover is working at 90 degrees to the pushrod and the ball is still in it.
Cheers
Title: Re: Stiff clutch lever
Post by: Guy Wilson on 06.10. 2017 22:17
thank you all..lots  to check in the morning!
Guy
Title: Re: Stiff clutch lever
Post by: Guy Wilson on 06.10. 2017 22:18
Its an early swinging arm model with a later 4 spring clutch
Title: Re: Stiff clutch lever
Post by: JulianS on 06.10. 2017 22:33
Most 4 spring conversions use the 6 plain and 5 bonded plate item which takes spring cups 1 3/8 inch long.

There is also a 4 spring clutch used on dynamo 500 Triumph which took 1 less of each plate and used shorter spring cups and  inner drum. Cups were about 1 inch I think.

I would check the length of the cups is right for the number of plates in your clutch.
Title: Stiff clutch lever
Post by: Guy Wilson on 07.10. 2017 06:33
that's worth looking at..the lever, cable, activator, rod all move freely..
Guy
Title: Re: Stiff clutch lever
Post by: duTch on 07.10. 2017 06:51

 So there's smome confusion here;

 
Quote
My '53 Golden Flash has a later 4 spring clutch. T
,

 but;
 
Quote
Its an early swinging arm model with a later 4 spring clutch

 ...so unless I missed something else, it can't be a '53, as the S/A's didn't happen until '54 *conf2*; which doesn't really matter much because the clutch is having issues whatever it is
Title: Re: Stiff clutch lever
Post by: JulianS on 07.10. 2017 09:45
The first swinging arm A10s left the factory in November and December 1953.
Title: Re: Stiff clutch lever
Post by: Peter in Aus on 07.10. 2017 09:58
Try cutting the clutch push rod in half and adding a ball bearing in the middle you will have to harden the cut ends and shorten the rod by the size of the ball I think it is 1/4 or 3/16 cant remember but it dose make it easier.
Peter
Title: Stiff clutch lever
Post by: Guy Wilson on 07.10. 2017 16:09
So once again...thank you all and especially JulianS for making me look at something I thought was ok.. you were quite correct in diagnosing a badly routed and badly lubricated cable. It wasn't until I took the cable off that it that there was a kink despite it appearing fine on the bike.. Its now a two finger pull...
Also, if the magneto is correct, I have a March, 1955 Golden Flash and not 53 as previously stated..
I would have been stretching my head in frustration for days, possibly weeks without your help.. It again proves the tremendous worth of this website!
Many thanks
Guy
Title: Re: Stiff clutch lever
Post by: duTch on 08.10. 2017 00:21

 Good you got the clutch sorted.

 I don't want to turn this into a dating thread, but;
Quote
Also, if the magneto is correct, I have a March, 1955 Golden Flash and not 53 as previously stated...

 More than possible the maggy has been changed. Since I've had dating charts available, I'm aware that bikes made have been built in the year ahead of the model year. Mine has 23.12.52 stamped in a couple of places, so maybe like you I've always called it a '52 but now accept is a '53 (with a BA **** eng.#) but in a '56 frame- so It's now " '50's "  *smile*.
 One way you can check is this chart kindly submitted by others on more relevant threads;
https://www.britbike.com/bsapitstop/dating/1951-60.html (https://www.britbike.com/bsapitstop/dating/1951-60.html)


Title: Re: Stiff clutch lever
Post by: RichardL on 08.10. 2017 02:18

Quote
Mine has 23.12.52 stamped in a couple of places...

Awww, that's nice, a Chistmas bike. Last one grudgingly assembled just before taking off for holiday.   *smile* ;)

Richard L.

Title: Stiff clutch lever
Post by: Guy Wilson on 08.10. 2017 10:30
Engine number is CA10 7100
Frame number is CA712326
Clutch is working very well now ! Left hand exhaust valve seems to be burning a little oil..that's my next job..
Guy
Title: Re: Stiff clutch lever
Post by: JulianS on 08.10. 2017 11:32
I would saythose numbers are from the late part of the 1955 season - May June or July 1955.

Photo 1 from Glass's Motor Cycle Check book 1946 -1958 edition. Published in 1958.

Photo 2 explains Glass's check books if you have not seen them before. They were mainly for models sold in the UK to enable dealers to identify models
Title: Re: Stiff clutch lever
Post by: Guy Wilson on 08.10. 2017 16:59
thank you! Mine came up from Southern Africa to Kenya. I think it had a Rhodesian registration  number.
Guy