Clutch parts confusion...

[RichardL]

Lucky for me this topic came up.

After reading, I went out to the garage to check the angle of my own clutch arm. It was right, having set it according to the "90 degrees to the cable" method but, in the process I discovered the cable was well frayed at the top. What to do, what to do? There is a vintage bike show this Sunday which I plan to enter. Voila! Once again my A7 barn find comes to the rescue with a good clutch cable that fit properly after trimming back the spiral armor to fit the top adjuster. 

Richard L.

[metalflake11]

S.R.M. are right, it should be parallel to the gearbox with the lever pulled in. It's exactly the same principal as a brake lever on the brake drum.

[a101960]

S.R.M. are right, it should be parallel to the gearbox with the lever pulled in.

Ah, metalflake 11, but that is not what SRM said according to what oldbeezargeezar posted.

SRM told me the clutch actuating arm should be 20 - 30 degrees away from gearbox gasket but Haynes says it should be parallel.

If oldbeezageezar has stated what SRM told him literally, then SRM were wrong in what they said. It is true that the actuating will end up being 20-30 degrees with the clutch engaged, but that is not the correct way to set up the clutch. Crucially the correct procedure is to set the actuator arm as described by BSA in the A7 / A10 owners instruction manual, which is to set the arm parallel with the clutch lever pulled in. That is not what SRM appear to have said.  What SRM actually said according to oldbeezageezar is misleading, and wrong.

[RichardL]

All very semantically confusing because engaging the clutch lever disengages the clutch.

Richard L.

[metalflake11]

S.R.M. are right, it should be parallel to the gearbox with the lever pulled in.

Ah, metalflake 11, but that is not what SRM said according to what oldbeezargeezar posted.

SRM told me the clutch actuating arm should be 20 - 30 degrees away from gearbox gasket but Haynes says it should be parallel.

If oldbeezageezar has stated what SRM told him literally, then SRM were wrong in what they said. It is true that the actuating will end up being 20-30 degrees with the clutch engaged, but that is not the correct way to set up the clutch. Crucially the correct procedure is to set the actuator arm as described by BSA in the A7 / A10 owners instruction manual, which is to set the arm parallel with the clutch lever pulled in. That is not what SRM appear to have said.  What SRM actually said according to oldbeezageezar is misleading, and wrong.

All very confusing isn't it?
 If you look at the gearbox arm from above from the timing side, it should be where the hour hand would be at half past eight. When you pull the clutch in, it should be at nine o' clock. When the clutch is released the arm should be free to move slightly to prove it is not pushing the pushrod and not being pulled by the cable.

[oldbeezageezer]

well, thanks to all you and to bsa-bill from an old thread. I got earlier SRM fitting instructions which were a lot clearer than the one they gave me with the clutch. My dilemma was setting the actuating arm before cutting the push rod. With the advice I got out in the garage and did the deed. Cut the push rod, (and hardened the end) and fitted the pressure plate, springs and adjuster.
It seems to work ok.  I couldn't get the actuating arm at 90D to the cable so will have to do final tweaks when I get running.  It will probably be a while as I was going to refit the primary chain but now the new clutch doesn't wobble on the shaft, it doesn't fit.
While waiting for the new clutch to arrive I took the rocker box off to sort out the, or I should say, one of the oil leaks. New gaskets, gasket cement, push rod tool so all set. Fiddly job which I did not think would be easy but no matter which way I fiddled, I couldn't get the box back on. Discovered two of the studs are bent! I thought studs would be an easy thing to get but on my bike the rear studs are longer than the front and all four appear to have the same part number and from what I have read here, all the same length.
It looks like shorter studs at the rear will be ok but does anyone know a part number for the longer studs. By the way, my engine has an aluminium head.

[muskrat]

G'day OBG.
Alloy head rockerbox's have 4 studs the same size pt# 67-1117 http://www.nsamotorcycles.co.uk/67-1117-bsa-a7-a10-alloy-head----rocker-box-fixing-stud-4371-p.asp
The top rear tappet inspection cover stud should have flats to be able to remove it. Makes the job a tad easier.
Cheers

[oldbeezageezer]

Thanks for the info and link Muskrat. I will order some and hopefully get back on the road before the end of our summer. Guess it's just warming up for you to get out and about.

Alan