Britbike forum Forums British Motorcycle specific Brands Bsa bulletin board A65 Clutch Cush Drive Screws Loosening

I installed a center hub that has through bolts, I have done this same repair before and with the through bolts most likely it will not need to be done again.

With the clutch lever pulled in all the way in first gear it now just barely creeps forward. The screw in the center of the clutch was adjusted all the way in and then out between 1/2 to 3/4 turn with the clutch cable unhooked from the clutch hand lever. This could be another post.

Thank you for the replies.

are you using the factory pressure plate or an aftermarket one (say from SRM)? the factory pressure plate uses a finer thread to the aftermarket ones (I think the SRM is UNC from memory), if it is the aftermarket one you will want to back the screw off by 1/8th-1/4 turn as anything much above this will not give enough lift and cause the bike to creep when the clutch is pulled in.

Examples of common punches from a US catalogue https://engineeringlearn.com/types-...king-principle-advantages-disadvantages/

Although I haven't heard of the name "p***k" punch before.

I have always run factory pressure plates on my A65s and I found that the "1/2 to 3/4-turn out" spec in my Chilton manual was too much, would cause the clutch to drag, particularly when warm. I've always attributed this to the clutch discs swelling. I believe the OE discs, which were on my '67 L when I got it, but only for a short amount of time, did not swell to the same degree as the aftermarket cork discs. This could explain the seemingly erroneous adjustment spec in the books, but this is only a theory based on a sample of ONE.

Also, the adjuster nuts need quite a bit of fine tweaking in order to get the pressure plate moving back and forth evenly.

One of my adjuster nuts was locking up on the spring, so I reversed (the spring) and it cured that problem. I noticed somewhere that some had filed off the indentations on the nuts, but not sure whether that's a good idea.

Some things that cause clutch drag.

Pressure plate spring pressure imbalance. Correct by adjusting spring pressure,

Warped steel plates.Replace plates warped by 3thou or more.

Worn cush drive. Replace with new unit.

Primary chain missaligned, check shims behind sprocket.

Clutch centre adjuster fouling with inspection cap at full lift, either shorten push rod or fit a thick O ring to the capto move it out.

Any single item above or combo will cause the machine to creep with the clutch held in.

A good list, but I found that checking the primary chain/sprocket alignment to any fine degree is problemati.c

The clutch did not creep before this repair. The adjusting screw is 3/4 turn out. The pressure plate was not changed and should be stock. It does work okay, but it just creeps forward very slightly at a standstill when running in 1st gear and the clutch pulled in all the way.

Straight edge, easier with the bike over on it's side.or before engine fitted.

Possibly the pressure plate is lifting unevenly,please note that the spring pressure adjusters must be operated in whole turns,( This is because the adjuster nuts have locking pips, if the spring is not seated against the pip it will turn in use until it is seated) start with the adjuster threads level with the nuts, operate the clutch and note any uneven lift, adjust the spring pressure to give even lift all round, dont worry if the thread protrude or recess unevenly , so long s the plate lifts even and clean all round it is good to go. If you have trouble turning the pressure adjusters because of the pips use the tip of a butter knife to ease the spring past the pip.

If the clutch isn't disengaging, I would start by looking at the cable adjustment and whether the lever (or ball lifter) in the timing cover is adjusted properly and has the ball bearing in place which bears against the pushrod.

When you rebuilt the clutch center, you probably removed the clutch push-rod from the left side, the clutch lift mechanism on the TS has a ball bearing, which bears against the clutch push-rod. It would be worth checking if the ball bearing is still in place or not. If its missing you will have inadvertently shortened the push-rod hence the clutch cant fully disengage.

If the ball bearing is in place, the way I adjust the clutch is as follows (note, others may have their own ideas, this is just mine):-
- as a starting point, make sure all the springs are the same length and also the spring cups have the same depth. Its not unusual to find mismatched parts here.
- with the adjuster on the pressure plate undone, start with adjusting the cable so that when the handle bar lever is pulled in, the lever mechanism in the timing cover is fully pulled in, but not fouling or grounding on any parts of the cover.
- screw in the clutch springs as far as they will go and then unscrew each by an equal amount (e.g. 1 turn), these settings will later be used to check if the clutch needs more free play to disengage
- turn in the adjuster screw on the pressure plate so its just touching the pushrod, then back off by 1/2 a turn
- pull the handlebar lever and try kicking over, ideally the clutch plates should disengage
- if the clutch plates dont fully disengage try unscrewing the springs all by 1/2 turn and see if its any better.

You should arrive at a point where the clutch disengages enough and doesn't drag but also doesnt slip when running.

I think the ball bearing at the end of the clutch rod is 7/32", I always seem to lose mine somehow when taking out the push-rod and I've temporarily replaced with a 3/16" ball which I had.

3/4 turn out is too much. Try 1/4 turn out. And adjust it when it's warm.

I noticed that the adjusting screw in the center of the pressure plate looks to be too far into the locknut. After noticing this I removed the adjusting screw and pulled out the rod. The rod looks okay on both ends, there doesn’t look to be any wear on it so I would think that it is okay.

Any suggestions about the adjusting screw being too far in?


At this point I also want to adjust the 3 screws on the pressure plate so that it rotates evenly.

Any tips on adjusting the 3 spring screws so that the pressure plate rotates evenly?

If the centre screw is too far in then when you adjust it, it will be adjusting against the main shaft and not the push rod. The pushrod should be poking though by a few mm when there is no tension on the cable, so push against the rod and see if it is still proud. Following that, as long as the nut is fully On the adjustment grub screw then all should be ok.

For clutch adjustment, start off with all the screws with the top of the heads flush with the screw tops. Then push against the plates and check the gap behind them. Adjust the adjusting screws in or out until there is an even gap all round.

Before you do, check all the spring cups are the same length and if possible, check the springs also, if you don’t know the history of the springs, get some new ones from a reputable supplier.

Alan, I don’t quite follow what you are saying about pushing on the clutch plates and then checking for an even gap behind them. Could you try explaining this another way?

Thank you for replying

I think what Alan meant is "with the clutch disengaged, push the clutch plates away from the pressure plate and rotate it with the kickstart while checking the gap all around"... or something to this extent.

I usually eyeball the pressure plate while rotating it to make sure it's true but, back when I had an issue similar to yours with creeping forward, I used a dial indicator against the outer edge of the pressure plate. It doesn't usually take a lot to get the plate to spin true. (in my case, the creeping turned out to be due to screws that had backed out, exactly like you at the start of this thread).

Marc

Yep. Thankyou Marc for clarifying for me.

I think it’s always worth adding and this is as good a time as any that when you buy these old bikes, you need two things in your arsenal. One is a parts book for your year of bike. The other is a workshop manual (preferably the factory manual) for your year.

Changes were made year on year and you’re best getting what is for your bike. It probably sounds like I’m having a dig but this is not meant to be as such.

The wsm will answer most questions and often has really good diagrams showing how to do certain things. And list out special tools and how/where to use them (between the two books)

Would someone know the grade of the 3 bolts used in the clutch center and their torque specification?

The steel plates are not fitting well on the new clutch hub center that I bought so I returned it and will buy another.

I beleive the plates for the 4 spring unit are different than the 3 spring type and not as easy to get hold of. - but whilst I have a 4 spring unit in my garage, I haven't got a 3 spring one anymore to make a direct comparrison.

I received the new clutch hub center that has through bolts and the driven plates slide pretty well onto this one. The driven plates did not slide easily onto the first clutch hub center which I believe is at least part of the reason for the clutch dragging. Everything is installed and the clutch springs and center rod adjusted. Next is putting the primary cover on.

Does someone here know the amount of oil to put in the primary case? I cannot find this in the manual. 1/3 pint or 1/2 pint.

To avoid the confusion between Imperial and American pints, I go by the Metric spec: 140cc (or 140ml, same thing).

The primary chaincase has two special lower perimeter screws, originally these were painted red and used special sealing washers. If you inspect the screw bosses on the lower inside part of the chaincase you will seee where the screws go, one screw boss is drilled on the top side, this is the oil level,the other screw boss which has a milled down section is the drain,. To fill , put the bike on the centre stand , remove slottted inspection cap upper most on the case, remove the level screw and put a pan beneath it, fill thru the upper cap hole untill oil dribbles out of the level screw hole, stop filling, let the dribble slow to a drip, replace the screw and cap, no need to measure anything. Every A65 manual I have shows the drain and level screws in a pic , the 1970 manual shows this on page B24 figure B38, the Haynes manual has the same pic on page 31.On a stock bike the level screw is just in front of the brake pedal footpad and the drain is just to the rear of the footpad, the screws can be sealed with Al, or fibre washers, you can make your ownfibre washers using a pistol dril and some sand paper, most auto shop 1/4 bore fibre washers will work , if the OD is too large, it can be reduced easily by bolting a few on a 1/4 a screw , chuck it in a drill the reduce the OD on some 100 grrit paper