Hi to all again.
A while back I tried to describe the pins in the timing side that limit the travel of the gear change return mechanism and it seemed to cause a bit of confusion.
I ended up copying the text from a service bulletin for the American market that highlighted the flats on these pins that dictate how far the return mechanism moves and how they should be sitting.
Most people that replied could not picture these pins as they were obviously not in their particular model of A65.
I was on Ebay today and found these pictures of the two different timing side cases.
Hope this shows what I was meaning. Both show the apertures for the kick start lever and also for the gear change lever. I'd imagine the one with just the one pin (where the return spring sits) is of a later design.
Regards
Clarke
As far as I can see, up to 1965, the stop plate (68-3083) included an extra arm that limited its up and down movement between the two anchor pegs (68-3058). However, from 1966, the stop plate (68-3298) no longer had this arm and therefore the upper anchor peg was no longer required while the lower one continued to be used to control the return spring. That said, couldn't see any flats on the examples of the early anchor pegs I could see but can understand why these might have been used to refine the amount of movement of the cam plate :)
Thanks for the info Spaceman.
The stop plate I have in place is the later one which must have been fitted as the originals are no longer available.
It begs the question, would removing the top pin and making it like the later set up help the gear changing?
Clarke
With the later stop plate fitted, the top anchor peg will not now perform any function and so removing it will not make any difference to the way the gear change works.
My best understanding of how the gear change works on the A65 is as follows:
Up to 1965, the up/down movement of the gear change lever, and the quadrant it rotates to move the cam plate, was limited by the arm on the stop plate hitting the two anchor pegs on the outside of the inner timing cover.
Post 1965, the up/down movement was limited by shoulders machined on the re-designed quadrant (68-3294) hitting projections on the inside of the inner timing cover.
The implication of this would seem to be that if you have a pre-1966 engine and it is fitted with the later stop plate then there might now not be anything limiting the movement of the gear lever and quadrant. At the very least, the gear change might feel a little strange but whether this might result in damage to the gear box is less easy to predict :o
Thanks again.
So if anyone out there has a stop plate that Spaceman was talking about (part 68-3083) and the spring (68-3084), please get in touch and I'll gladly buy them. Anything to try and sort the poor shifting I've been experiencing.
Thanks and Regards
Clarke
As I've found in the past, it's sometimes easier to find BSA parts in the US than the UK although at the moment shipping times are a little excessive:
https://www.baxtercycle.com/product/68-3083/
Hi,
I think I may have one. I will have a look and let you know.
Dave.
PS. I have it in my hand. Not found a spring yet.
Thanks Dave.
Much appreciated.
Clarke
Clarke, out of interest, what are the gear change symptoms you have at the moment and is it simply that you are missing the stops that should limit the gear lever movement?
Hi spaceman, I've had the bike for about 9 months now. Initially the bike wouldn't start or run very well an would usually stall when selecting first gear. Once running, it would go up through the gears reasonably well but slowing down coming to junctions, lights etc, getting into second from third was a hit or miss affair. Finding neutral very difficult a very often it wouldn't go back into first. It felt at first like the clutch wasn't disengaging.
Usually this meant stalling at the lights and rocking the bike back and forth while getting first using my hand.
This happened every run and became really frustrating. Since about September the bike has been in my parents garage while I've gone about fitting a new monobloc carb, electronic ignition, changing a damaged alternator, going to 12volts and stripping and rebuilding the clutch as I want this to be an everyday bike in the Summer.
I've been reluctant to delve into the gearbox and I know that it could be selector forks, gear damage or a number of other issues, but the feeling I was getting through my right foot was the the lever wasn't travelling sufficiently to engage the selector in the camplate.
Someone posted the service sheet that listed the pins and mentioned grinding a bit off the stop plate for more travel so that's what I've been concentrating on.
Clarke
Clarke, it doesn't sound as if the problem is caused by the wrong stop plate - this would lead to too much gear lever travel and not too little. I'll go and measure the up/down travel on my A65 and it will be interesting to compare with yours.
To some extent, part of the problem sounds like clutch drag which would make it hard to change gear and find neutral. A good test of this is to try going through the gears with the engine not running - if you can change gear easily like this then clutch drag may be the cause of some of the problem.
If it's not clutch drag and not due to the stop plate, unfortunately, you may have to remove the inner timing cover and examine the condition of the gear change mechanism components.
Ok. I'll give it a try at the weekend as that's my next day off.
Thanks again.
Clarke