The BSA A7-A10 Forum

Technical => Clutch, Primary, Gearbox => Topic started by: Gasket4450 on 22.02. 2016 19:37

Title: Kickstart jamming - This Could Happen to You !!!
Post by: Gasket4450 on 22.02. 2016 19:37
                         Apologies to everybody, as I know this subject has already been done to death, and this is quite a lengthy post, but if it stops anybody else making the same mistake, it will be worth it.
           For some considerable time, the kickstart on the A7 has been jamming. If I am honest, it’s been doing it from day one, but just lately it has been getting worse and worse. My usual method of dealing with it is to free it on the clutch, and then give it even more GBH with the size 11 boot.  Yesterday, it jammed completely, half up and half down, and would not move an inch either way.  Uh oh, not good.  So I spent what was left of yesterday reading the various posts on the subject on this forum.
                             Finally, I plucked up courage this morning, and took the gearbox apart. What a mess!  A badly chewed kickstart quadrant, and piles of swarf and other sundry particles in the bottom of the cases. The strange-looking extra shoulder in front of the stud hole casting in the first picture is not reinforcement, it is in fact a pile of swarf and filings!  Some of the more sinister looking bits can be seen further back in the bottom of the case. Uurrgh!!
      On examination I discovered all the bushes in the casings were worn, which had probably exacerbated the problem by allowing the kickstart shaft to slop backwards and forwards slightly, thereby increasing the likelihood of the teeth not meshing properly. There was a lot of play between the ratchet pinion and the ratchet pinion bush ( over 0.008 at least ), again not helping matters. Once the ‘grinding down ‘ process had started, it was only a matter of time before the inevitable happened – check out what happened to my kickstart quadrant in the pics.
      Anyway, it appears I had done the unforgiveable.......I had matched a ‘ flat top ‘ ratchet with a ‘ pointy ’ quadrant, obviously a recipe for disaster. Instead of checking it earlier, I had just carried on regardless, giving it more and more welly each time, without stopping to think what might be going on in there. What a bonehead, eh? What is more annoying is that I paid a lot of money for this ‘ completely refurbished ‘  gearbox from a so-called specialist, although I have had it for some time, but only fitted in 2014, and only done 1000 miles. So, another lesson learned there, then. Do it yourself next time, Thompson.
      However, it is not all bad news, as I have a NOS quadrant and shaft, and three of the four new bushes I need, so it won’t be too expensive. I shall order a new ratchet pinion and bush, and a new inner case kickstart shaft bush from my old friends at Lyford Classics tomorrow – always good service from them. And a couple of gaskets too, as I had to take the inner cover off as well. I couldn’t run the risk of swarf being in there too. Good job I did, as some swarf had managed to get into the inner case bearing, so I’ve stripped the box and cleaned it thoroughly. All in all, a lot of unnecessary work caused by me being stupid, really. Anyway, let my stupidity stand as a timely warning to others, I say.
All the best
Norman T
Title: Re: Kickstart jamming - This Could Happen to You !!!
Post by: chaterlea25 on 22.02. 2016 20:58
Hi Norman
Hmmm *sad2* *sad2* *sad2*
Some time ago I was looking for some flat topped ratchet gears,
Eventually I managed to find some,  BUT
When they arrived they were oversize in the bore, same as you have found  *ex* *ex* *ex*
I made a couple of new bushes to suit as the sellers stock were all the same
The seller gave me a very decent discount because of the problem found

Caveat Emptor *ex* *ex* *ex*
John
Title: Re: Kickstart jamming - This Could Happen to You !!!
Post by: Gasket4450 on 22.02. 2016 21:15
Thanks, John.         Yes, I've already discovered that. There are two distinct sorts of pinion on sale, one with I.D of 3/4", and one with 24mm ! I have also found two different BSA part numbers:  67-3168 and 67-3376, but haven't figured out yet which is which !!! However, I believe the one I need for my nice new pointy quadrant is 3376, the larger bore.  Pic of 4 odd ones I have, 3 large internal diameter, 1 small. ( The small one does not go on the standard A10/A7 pinion bush )
Regards
Norman
Title: Re: Kickstart jamming - This Could Happen to You !!!
Post by: KiwiGF on 22.02. 2016 22:58
Mine jams but frees up pretty easily after pulling the clutch lever in...I thought this wss normal?

should I be worried?
Title: Re: Kickstart jamming - This Could Happen to You !!!
Post by: Gasket4450 on 23.02. 2016 02:14
Hi KiwiGF. You only need to worry if you are negligent like me. I think they all do it to a certain extent. Not a problem if you look after the old girls. Just need to be aware of the early signs and symptoms, such as difficulty in engaging the kick start, and graunching noises from the gearbox. Ignore them at your peril !
Have a nice day
Norman
Title: Re: Kickstart jamming - This Could Happen to You !!!
Post by: muskrat on 23.02. 2016 11:30
"Ah, they all do that sir" Both mine lock from time to time. I find kicking them on the side stand rather than the main stand helps. 9 out of 10 it's a worn pinion bush and/or worn spindle bushes.
Most if not all your damage Norman is the quadrant/pinion miss match.
I bought a pinion for the A65 last year. I could throw it on from the doorway! I made a bush to suit then a month or so later a new bush arrived from the supplier. So if anyone needs an oversize bush to fit the dodgy pinion, free + post.
Cheers
Title: Re: Kickstart jamming - This Could Happen to You !!!
Post by: bsa-bill on 23.02. 2016 11:34
yep my RGF does but the Flash never has, fitted some new bits but still does it occasionally, read somewhere (here most likely) that over-tightening the  nut can squash the bush out of shape a bit and cause it.
 
Title: Re: Kickstart jamming - This Could Happen to You !!!
Post by: Topdad on 23.02. 2016 11:58
Mine hasn't locked up for quite a while ,free'd as per via pulling the clutch. Norman the only worse quadrant I've seen came out of box my mate picked up ,in the end  it was working by friction alone  virtually no teeth left at all .That owner had been totally indifferent to what was happening inside but suffice to say the swarf had destroyed every bush and bearing in the box so you shouldn't feel to bad about what happened.
Title: Re: Kickstart jamming - This Could Happen to You !!!
Post by: Gasket4450 on 23.02. 2016 13:09
        Oh, wonderful, I feel so much better now...... *cry*

             Yes, you're probably right Muskie, everything was moving around in there much more than I was happy with, so new bits all round should fix it.
Cheers

Title: Re: Kickstart jamming - This Could Happen to You !!!
Post by: BVSR on 23.02. 2016 18:22
Hi,

67-3168 is for pre -54 and 67-3376 is for -54 on. The teeth profile is also different. Look at the pictures in De Groot´s site.

Markku

http://www.degroot-bsa.nl/index.php?route=product/category&path=51_60&page=3


http://www.degroot-bsa.nl/index.php?route=product/product&path=51_60&product_id=751
Title: Re: Kickstart jamming - This Could Happen to You !!!
Post by: Gasket4450 on 24.02. 2016 21:13
Thanks Markku, I thought it might be something like that. The problem in this country is that they are sold as one and the same item by a number of retailers, which is not helpful. I now have the correct item. 
Regards
Norman T
Title: Re: Kickstart jamming - This Could Happen to You !!!
Post by: Gasket4450 on 02.03. 2016 11:38
                  Everything now back together, a complete new set of bushes, new ratchet pinion ( pointy teeth, from Monty's Classic M/Cycles on EvilBay ), and a nearly near quadrant. Everything working as it should now. Another lesson learned......

Thanks to all, and roll on Spring
Norman T
Title: Re: Kickstart jamming - This Could Happen to You !!!
Post by: paulmbsa on 13.03. 2016 08:27
if it jams do not force it, put it in gear and rock it GBH Never works in the long run
Title: Re: Kickstart jamming - This Could Happen to You !!!
Post by: duTch on 18.03. 2016 10:57

 Over the last couple of weeks time and interest permitting, I've dissected all five boxes I have, including the one in use. they are in various states of explosion, but not all have ratchets, but some of the ratchets are so worn I've no way of knowing how they started out (flat-topped or pointy). No big deal, but they all have a bush with OD ~0.931/Pinion I.D ~0.940.
  Still no big deal, But Norm (gasket4450), I'm wondering how/where that pinion with the 3/4' bore fits into the scheme, as that's about the shaft size- doesn't matter, just curious so I don't end up with one?
Title: Re: Kickstart jamming - This Could Happen to You !!!
Post by: Gasket4450 on 18.03. 2016 16:46
Hello Dutch.  Somebody more knowledgeable than yours truly here had a look at that one, and recognised it as probably belonging to an old M series box, the one that lays on its side, as it were. I had always assumed it was A10 as it came in a box of assorted  A10/A7 bits from Fleabay.  ( The same scenario as the jolly japester who drops a couple of ciclips on you garage floor when you're not watching, as you're too busy beaming about the 3 year rebuild you've finally just finished !!! ) *problem*
Regards mate
Norm
Title: Re: Kickstart jamming - This Could Happen to You !!!
Post by: Greybeard on 18.03. 2016 17:33
...the jolly japester who drops a couple of ciclips on you garage floor when you're not watching, as you're too busy beaming about the 3 year rebuild you've finally just finished !!! )
That is evil!!
Title: Re: Kickstart jamming - This Could Happen to You !!!
Post by: KiwiGF on 18.03. 2016 19:31
Or the newly rebuilt A65 engine (not mine) with the spark plugs out in the workshop just waiting to be timed before being fired up, and the little boy exploring the workshop who thought secretly dropping a few 1/4 inch half nuts down each hole would go unnoticed  *eek*

It did for a couple of hundred miles....and then knock knock rattle rattle and into the support van it had to go.

The "evidence" found when the bike got home was hex shaped impressions all over both pistons and the head.......and a smaller pile of nuts on the bench.

The total repair bill will depend on whether there is big end damage  *pull hair out*

At time of writing the little boy has yet to be "interviewed".
Title: Re: Kickstart jamming - This Could Happen to You !!!
Post by: bsa-bill on 18.03. 2016 21:42
Quote
At time of writing the little boy has yet to be "interviewed".

MMMM - might I suggest before the interview you cast your mind back a decade or three. or four . or ......