Author Topic: 1955 A10 Golden Flash 650cc - swinging arm model - clutch problem  (Read 3533 times)

Offline BrianS

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A10 clutch p*rn  ;)

I know what I will be doing tomorrow. Looks a nicely made bit of kit.

I am guessing the felt seal goes behind the big oval plate underneath the old clutch?

Best RTFM I guess   *smiley4*

Brian
1955 BSA A10 Golden Flash
Exeter, Devon, UK

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Hi Brian,

The SRM shaft adaptor does not have a scroll so the felt sits between the sliding plate and adaptor ,
it fits over the shoulder of the adaptor
Another large felt sits between the sliding plate and inner case,
The replacement ones seem to be pretty useless in my experience !!
I have used cork gasketing in its place but recently I was able to get some special kind of rubber ones
from Dave Flintoft, (none listed at the moment)
http://www.ebay.co.uk/sch/dfegold/m.html?ssPageName=STRK%3AMEFSXS%3AMESOI&_trksid=p2053788.m1543.l2654

Some sliding plates can leak like sieves between the two parts they are made from *eek*
degrease and run a bead of sealer into the "v"

HTH
John
1961 Super Rocket
1963 RGS (ongoing)

Online cyclobutch

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As a complete aside, I've recently been working on a Morini Camel 500 - though I think the architecture on their vee twins is all broadly similar. It's a 5 spring device that runs dry under a small cover with just four retaining screws on the LH side of the motor. I had hellish trouble removing the nuts from two of the five studs and ended up Dremeling the cups away so that I could get the pressure plate off to then remove it all. The studs screw into the inner drum and then peen over into a chamfer. So not too difficult to drill out and then unscrew and save the springs.

Main issue was oil ingress which was causing clutch drag, not slip, and I replaced three separate oil seals behind it all. I'd have to say that now it is all put together better it is the work of moment to go in there and poke about. Not that you should have to too often - the nuts pull right down (hence two were too tight) so there is no adjustment to be made.

Next issue will be the linkages that turn it from a right foot to left foot shift. Favourite would be to ditch it all resort to use of the right foot of course.     

Still running a 6 spring on the A10. Still wishing to switch to the SRM device - but mine just isn't quite bad enough to move me to put my hand in my pocket.
Various, including ...
'58 Iron Head Flash Bitza


Online KiwiGF

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I've just checked the srm site and it looks like it's 393 gbp for the srm clutch kit, that's getting close to a bob newby belt drive conversion! (Both out of my (eg. My wife's) budget range)
New Zealand

1956 A10 Golden Flash (1st finished project)

1949 B31 rigid “400cc hot rod” (2nd finished project, + favourite bike)

GL1800 Goldwing, well, the wife likes it

KTM 950 ADV, cos it’s 100% nuts

1952 Armstrong Siddeley Whitley for rainy days (with wife)

Offline BrianS

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I confess that I haven't taken all the advice on board in my enthusiasm to get Flash on the road again. It will probably come back and bite me but at least the clutch is now fitted and a quick test run shows it to be working fine. Not absolutely sure about whether it has made it easier to find neutral. I found it easily once and then selected 2nd and stalled it.  I will let you know.

I was a bit surprised how easy it was to fit the clutch and was a bit confused by the inclusion of a coloured fitting guide which seemed to indicate I would have to chop a bit off the push rod!

I am still surprised that there isn't a ball bearing at the gearbox end of the rod. It seems to have a cup in it to accommodate one but I am guessing the operating lever has a matching round face.

The second photo is to indicate what my interpretation is of SRM's instruction to have at least 1 coil of the spring showing above the top of the spring cup. Any SRM experts can advise if I have it right please?

Brian

1955 BSA A10 Golden Flash
Exeter, Devon, UK

Offline a101960

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Quote
was a bit confused by the inclusion of a coloured fitting guide which seemed to indicate I would have to chop a bit off the push rod!
Normally the SRM clutch assembly includes a radial roller thrust bearing, and to fit this the push rod needs shortening. Do you mean that you were able to fit the thrust bearing without shortening the rod? If you have any trouble finding neutral while stationary set the clutch up with the aid of a dial gauge. This will transform the clutch action beyond all recognition.
John

Offline BrianS

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Hi John and thanks for the quick reply!

Looking at the SRM ad, it shows a mystery part that I can't recall seeing so I have had a rootle through the box and found the "missing" part under the packaging  *sad2*

So I know what I will be doing tomorrow now  :!

Brian

PS I will have to Google "dial gauge"!

1955 BSA A10 Golden Flash
Exeter, Devon, UK

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Hi Brian,
Ahferfu*ksake  *ex* *ex*

The part you have indicated is the needle roller thrust bearing, fitting this means that the pushrod must be shortened
The pusher and radial bearing steady the pressure plate and help getting a truer lifting action
It is a necessary part of the design  *ex*

The other end of the pushrod sits against a ball bearing fitted to the operating arm adjuster
The pushrod  may take a bit of time to arrive at the best length
The operating arm and its bottom part with adjuster should be parallel
The arm should wind up parallel to the casing joint or a fraction further in with the handlebar lever pulled

You can make a wire pointer easily enough to get the pressure plate running true

Dont let your enthusiasm get in the way of doing the job properly  *ex*
Dont wait till all else fails before you read the instructions
  *eek*

John
1961 Super Rocket
1963 RGS (ongoing)

Online ellis

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Hi Brian.

The adjustment on your clutch springs seems too tight to me. SRM suggest one complete coil showing so I would back them off about two complete turns and this should give you a one finger clutch operation at the handlebar lever. Also SRM suggest not to use ATF but use 10/30w engine oil with no modifiers, and just 190cc of oil in the chain case so that the chain just gets a splash of oil now and then to lubricate it and also the clutch needle roller bearing. Too much oil in there could wet the plates too much with the possibility of clutch slip.

ELLIS

Offline BrianS

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Thank you for your patience John and for your advice on the clutch spring adjustment Ellis.

Following on from John's advice, I have taken the inspection cover off the gearbox side and the clutch operating arm is quite a way out of parallel with the bottom part that holds the adjuster - if I have understood correctly. I guess this means taking off the gearbox cover to adjust it but it begs the question why it was fitted out of parallel in the first instance?

I unscrewed the clutch adjusting screw to have a look at the ball bearing and, unfortunately it is more rugby-ball shaped than circular with substantial wear on one side. I assume this is scrap and needs replacement. Looking at the Draganfly pages I need part number 65-3403 but, sadly, they are out of stock at the moment. I have located a couple on eBay but have had to ask how much extra for 1st Class and to post tomorrow instead of the quoted "within two working days".

Worse still is that I can't follow the SRM instructions in terms of measuring the pushrod to determine how much to cut off.  SRM expect this to be done with the old clutch still in place. I really really don't want to take apart the new clutch and try and retrofit the old one if I can avoid it.

I will contact them in the morning but I would have assumed that if I shortened the push rod by the exact length of SRM's little pushrod I shouldn't be far wrong?

Brian
1955 BSA A10 Golden Flash
Exeter, Devon, UK

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Hi Brian,
First of all you need to get a new adjuster and its included ball,
It is possible (just about) to remove the splitpin nut and washer on the clutch adjuster with the end cover in place
The idea is to have the cable and arm travelling through a 90 degree angle ideal position when operating
during this the adjustable pusher should wind up in as near a  straight line with the pushrod as practical
If you have a 3/8 x26 bolt (old rear bicycle axle) you can fit it in place of the adjuster
Then the bolt and cable arm should be at 90 degrees when in the correct position
There should be a thread or 3 protruding through the locknut when you refit

To determine the pushrod length get all the above sorted first  *ex*
Assemble up the pressure plate without the centre adjuster, then use some thing like a welding rod and slide it through until it meets the pusher on the far side, mark the length
then measure up the SRM pusher,bearing and adjuster so as to place the adjuster nicely in the pressure plate
Trial cut the pushrod a little long, and reduce as necessary
Make sure the pushrod end is trued up square, and then re harden the end
Heat to dull red and quench

John
1961 Super Rocket
1963 RGS (ongoing)

Offline Billybream

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Brian do not worry if you cut the push rod short, a lot of us cut the rod in half and fit an additional 1/4" ball bearing between the cut ends (after hardening) further improving clutch operation.
If you mess up push rod just buy some silver steel rod as replacement.
1960 Super Rocket, owned since 1966, back on the road 2012 after being laid up for 29yrs.

Offline BrianS

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Thanks again for responses!

Reassuring to hear about the possible fix for an over shortened rod. Such a good idea to keep things smooth.

However, I have no engineering experience and would appreciate advice on how to cut/shape the rod ends square before hardening please?

Sorry to be so needy! I can strip down a TTR250 engine and gearbox to the last nut, bolt and bearing and rebuild without a manual but feel lost with the A10 and am making some silly schoolboy errors  *sad2*

A bit of good news is that eBay seller "irahnoo" will send the new adjusting screw in today's 1st Class post at no extra charge  *smile*   See http://www.ebay.co.uk/itm/361852575898?

Brian

PS I should have realised I was not the first to have questions - see http://www.a7a10.net/forum/index.php?topic=2890.0
1955 BSA A10 Golden Flash
Exeter, Devon, UK

Online ellis

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Hi Brian,

Where in the country do you live. Maybe one of us lives nearby and can call to show you how it all goes together. I agree it is a big leaning curve not having worked on A10s before but this forum is best place for resolving your problems. Stick at it, it will be worth it in the end.

Offline Topdad

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Hi brian if it goes wrong don't worry I must have 5 spare clutch pushrods I'll gladly send you one in fact if you'd like I'll send you one as a spare . Bob
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