The BSA A7-A10 Forum

Technical => Clutch, Primary, Gearbox => Topic started by: bobandbec on 11.12. 2015 16:06

Title: Changing gear
Post by: bobandbec on 11.12. 2015 16:06
Have noticed recently that when I'm on the A10 and wanting to change gear I can't get it to go in. This is both changing up and down the box. Once in gear everything is fine but becomes a real problem when I have to slow down and I can't get it to go into a lower gear or I'm wanting to go into a higher gear and I'm stuck in 1st or 2nd.
Any advice about what might be the cause?
Thanks

Peter
Title: Re: Changing gear
Post by: stu.andrews on 11.12. 2015 16:18
Clutch dragging-requiring adjustment?
Title: Re: Changing gear
Post by: Klaus on 11.12. 2015 16:29
I gues the gearchange returnspring is brocken. part number 67-3340 boah....footchange stop plate return spring.... *eek*

cheer Klaus
Title: Re: Changing gear
Post by: muskrat on 11.12. 2015 18:53
G'day Peter.
My first thoughts are as Stu and Klaus have mentioned. Plunger or S/Arm? What was the last thing you worked on before this started to happen?
Cheers
Title: Re: Changing gear
Post by: bobandbec on 11.12. 2015 20:32
Hi Muskrat
Done nothing to this except usual oil changes etc. Bought it a couple of years ago as a restored bike which had done about 200 miles in 3 years since the restoration. So still running in when I had it. It's a 1960 swingarm.
Has run like a dream (touch wood) since I have had it. Only recently noticed the gears "sticking" when running. One or two other little problems cropping up now but thankfully these I can handle.
The gears don't "grind" when changing. Just notchy and difficult to get out of/into gear.
I've got a new return spring ready so I can give that a go. Is it straight forward to do?
Thanks for the help
Peter
Title: Re: Changing gear
Post by: muskrat on 11.12. 2015 21:13
I'd still look at the clutch first. Important the pressure plate is lifting squarely.
The spring is an easy job. Do you have a parts diagram? Things to check while your in there.
#37 gear selector plate spring washer split spring.
#39 gear selector plate. Condition of teeth (rounded)
#52 gear cam plate pivot pin nut. Tight.
#67 gear control cam plate plunger housing. When lock nut is tightened about two threads should be viable. You could try backing it out a few threads to see if it makes any difference.
Cheers
Title: Re: Changing gear
Post by: morris on 11.12. 2015 21:50
Which oil have you got in the primary?
Asking this because some time ago I had the same kind of problem due to a to thick oil in the primary leading to a sticky clutch. Changed it to an even thicker one. Don't ask me why I did this because it only made the the clutch more sticky, but it seemed a good idea at the time... *conf2*
Since then, cleaned the clutch plates and changed the oil to an SAE 10 grade. Switches gear as through butter now.
Title: Re: Changing gear
Post by: bobandbec on 11.12. 2015 22:55
Thanks Muskrat, Not sure I understand completely what you're saying but I'll get the parts diagram out and study it in relation to your remarks. Sure it will slot together then.

Morris: I just use the Morris 20/50 classic in the primary as in the engine. I'll have a look at the clutch to see if it's contaminated when I look to see if it is running true.

Thanks

Peter
Title: Re: Changing gear
Post by: morris on 11.12. 2015 23:10
Morris: I just use the Morris 20/50 classic in the primary as in the engine
That's also what I first got in but as said, didn't work to well on the clutch.
Some here use ATF fluid in the primary with good result.