Author Topic: SRM clutch  (Read 2888 times)

Offline CotswoldsA7

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Re: SRM clutch
« Reply #30 on: 21.06. 2018 16:37 »
I totally agree with RogerSB re:Gary taking the trouble to post good info. I for one wouldn't hesitate using
SRM as and when a clutch job is needed. I guess it's a case of you get what you pay for including free advice. 👍😀

Online chaterlea25

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Re: SRM clutch
« Reply #31 on: 21.06. 2018 21:24 »
Hi All,
The oil I use in the primary is intended for wet clutch motorcycle engines (Castrol 10/40, Atevo ??)
No problems with the plates sticking, 4 spring clutch with Surflex plates

John
1961 Super Rocket
1963 RGS (ongoing)

Online metalflake11

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Re: SRM clutch
« Reply #32 on: 22.06. 2018 02:11 »
Hi All,
The oil I use in the primary is intended for wet clutch motorcycle engines (Castrol 10/40, Atevo ??)
No problems with the plates sticking, 4 spring clutch with Surflex plates

John

Exactly the same here. Two finger operation, no slipping, no dragging, no sticking.

It boggles my mind at times as to why people who work on bikes for a living, are questioned by people who do it as a hobby?
England N.W
1960 A10
England

Online orabanda

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Re: SRM clutch
« Reply #33 on: 22.06. 2018 02:12 »
As Gary Hearl points out, ATF is designed specifically for automatic transmissions; the oil has properties to cope with the application.

You might find this point interesting

One of those properties is to absorb (entrain) air bubbles. This leads to sponginess (compressibility) in the oil.

I have worked in the fluid power (hydraulics) industry all my life (and still at it). Occasionally we will receive a high pressure (10,000 psi) hand pump & ram assembly (with ATF in the pump reservoir) in for repair because it won't reach full pressure (will only get to 7,000 psi), and / or won't hold under load (it sags down).

The solution is to replace the ATF with mineral oil (10 - 32 cSt); the pump will then reach 10,000 psi, and the ram will not creep down. this takes all of 5 minutes.

The reason is the presence of air bubbles in the ATF, which is doing what it is designed to (capture the air).

As far as using ATF in primary drive cases, i don't. the recommended mineral oil does the job best. It is a higher viscosity (thicker).

Richard




Offline RoyC

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Re: SRM clutch
« Reply #34 on: 22.06. 2018 09:44 »
I've ordered this.

My bike is a 1958 A7SS
Stafford UK

Offline morris

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Re: SRM clutch
« Reply #35 on: 22.06. 2018 13:03 »
It'll always be one of those contentious topics (like Brexit) *smile*.
*yeah*

Did some experimenting with different oils in the past, and indeed found that a heavier oil made a stickier clutch.
In the end settled for a 10 monograde oil which works perfectly well in combination with the SRM pressure plate
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Offline nimrod650

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Re: SRM clutch
« Reply #36 on: 22.06. 2018 18:27 »
could you have a loop to slip over handlebar end to hold  lever in when stood ??

Online a101960

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Re: SRM clutch
« Reply #37 on: 22.06. 2018 19:15 »
Quote
could you have a loop to slip over handlebar end to hold  lever in when stood ??
Cable tie for instance.

Offline RoyC

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Re: SRM clutch
« Reply #38 on: 22.06. 2018 19:28 »
could you have a loop to slip over handlebar end to hold  lever in when stood ??

I had already given that a thought.
I use one of these to hold my front brake on when parked. (it's a combo)

I'll try adjusting the springs and changing oil first though.

My bike is a 1958 A7SS
Stafford UK

Online duTch

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Re: SRM clutch
« Reply #39 on: 22.06. 2018 23:19 »

 
Quote
could you have a loop to slip over handlebar end to hold  lever in when stood ??

 130g bean can (eat the beans first) / length of 50mm pipe/ hose clamp
Started building in about 1977/8 a on average '52 A10 -built from bits 'n pieces never resto intended -maybe 'personalised'
Have a '74 850T Moto Guzzi since '92-best thing I ever bought doesn't need a kickstart 'cos it bump starts sooooooooo(mostly) easy
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Offline RogerSB

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Re: SRM clutch
« Reply #40 on: 23.06. 2018 10:19 »

 
Quote
could you have a loop to slip over handlebar end to hold  lever in when stood ??

 130g bean can (eat the beans first) / length of 50mm pipe/ hose clamp

Wife's fingers  *doubt* , or as Roy suggested at one time your dog's teeth (if you have one)  *bright idea* , a rope and tie it with either a clove hitch or a snarling wedge snotter knot  *dunno2* ?
Me thinks we may have been here before  *smile*.

1960 Golden Flash

Offline KeithJ

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Re: SRM clutch
« Reply #41 on: 26.07. 2018 16:45 »
Replaced my Triumph 4 spring type clutch which has been on the bike for about 50 years with a new SRM one.

My old clutch worked fine.  Used all manner of oils over the years including ATF.  Never slipped and was easy to set up.  Was a bit worn though.

The new clutch has been problematic.  Have tried various grades of oil and get about 600 miles or so before it starts to slip.  Have just adjusted it again and note I have to screw the clutch nuts in much more than SRM suggests. 

Have one of Steve McFarlane's electric starters fitted and he says "I recommend automatic transmission fluid for this as it helps to stop the plates from sticking".  So who is "right"?

Will be interesting to see if my clutch has bedded in or starts to slip again.  i wonder if I have the wrong cups and springs or perhaps the plates have been contaminated.  Time will tell.

Thinking of putting the old plates back in with their cups and springs.

Just my experience.




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Offline lawnmowerman

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Re: SRM clutch
« Reply #42 on: 26.07. 2018 19:43 »
I have just stripped, cleaned and refitted the four plate (non SRM) clutch on my SR and it was full of sticky black residue, I think contributing towards clutch drag and difficulty engaging neutral with the engine running.
I originally used straight 40 oil in the chaincase but I did some research on alternatives. Most ATFs have friction inhibitors which is the last thing you would want on clutch plates. When I looked at the Castrol website, the red TQF is an older formualtion which does not have these friction inhibitors and is recommended by Castrol for motorcycle primary drives.
Being red it is also useful to identify where the leaks are coming from  *smile*
I have only taken it out once since and the clutch did not slip and felt good and neutral was easy to find after a 15 mile ride although that could have been partly due to making sure the pressure plate lifted evenly and slackening the far too tight primary chain.
I am not saying that SRM are wrong in not recommending modern ATFs, but Castrol are saying differently regarding the older TQF.
Who can you believe?

Jim




1959 A10 SR
1938 Wolseley 14/60
1955 Ferguson TEF20 tractor
1965 Ferguson 135 tractor
1952 Matchless G80 rigid
1960 BMW R60
1954 Matchless G80S
1955 Ariel 500 VH
1951 Sunbeam S7DL
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Offline BrianS

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Re: SRM clutch
« Reply #43 on: 27.07. 2018 13:10 »
This thread is timely for me as my SRM clutch is just beginning to slip a bit under hard acceleration (is there another kind?) so I am guessing the plates have bedded in and time now to adjust it. Correct amount of play in the cable.

A knowledgeable mate recommended ATF as it lubricates the primary chain better than oil he reckoned. But he wouldn't have known that SRM say not to use it so methinks I will stick to mineral oil.

I have only done about a thousand miles since fitting the SRM clutch and it transformed the bike allowing me to easily find neutral and a really light action. Should I need to adjust the clutch after such a low mileage?

Brian

PS Whilst working up the enthusiasm to do the job, I have ordered some washers to go under the case screws as I recollect "someone" recommending - these are they apparently - 5/16ths x 1/2" - first of the two here https://stainlessmiddleton.co.uk/search?controller=search&orderby=position&orderway=desc&search_query=Small+O.D.+Washers+5%2F16+x+1%2F2&submit_search=
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Re: SRM clutch
« Reply #44 on: 27.07. 2018 13:24 »
G'day Brian.
Do you mean the primary cover screws? If so their 1/4" ID and I think 3/8" OD 1/32 thick.
67-1709 https://tinyurl.com/yao4rakk  are fiber for the level and drain screws.
Cheers

Edit: Was thinking plunger, s/a have the three front ones 5/16".
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