BSA Owners' Club Forum

The BSA Workshop => Bantam => Topic started by: trophy on 06 July, 2021, 20:29:28

Title: D14-4 Gearbox assembly
Post by: trophy on 06 July, 2021, 20:29:28
Hello all.  Am having to sort out two problems with a gearbox I have just re-built.  Problem 1) is a kick starter that regularly locks at the top of its stroke but is OK if the crank is turned slightly.  Problem 2) is the gear change sliding gears on the mains and the lay shafts both have 21 teeth, but I have read that one should be 21 and the other 22 teeth.  Can anyone point me in the direction of an illustration and gear specification that I can refer to.  I cannot find anything on line.  If it means I need a 22 tooth sliding gear where would I get one from? All help much appreciated.
Title: Re: D14-4 Gearbox assembly
Post by: AdrianS on 06 July, 2021, 21:57:16
Without digging out my workshop manuals, I cannot help with the second question.
The first problem is a very common one and probably not related to the gear box. Mine locks occasionally and find I have to rock the bike to get it to free. Some people try relieving the first tooth on the kickstart quadrant and say that helps. I have changed my quadrant and it made no difference.
Title: Re: D14-4 Gearbox assembly
Post by: trophy on 07 July, 2021, 20:29:42
Thanks for the info Adrian. Much appreciated.  I will take another look inside the box to make sure its not an obvious fault.  The gears select fine so its a disappointment when the kick start plays up.  Re the 21 or 22 teeth sliding gears my manual tells me sod all but as the gears select OK I assume its not a problem.  Ride safe all.  Off to watch the match on tele.  Come on England.
Title: Re: D14-4 Gearbox assembly
Post by: Dean Southall on 07 July, 2021, 21:04:46
Bantam kickstart sticking at end of stroke is often due to lack of clearance in the outer engine case. Have you used a gasket for the outer cover? It is needed or the kickstart will lock up. If you have a gasket then try a thicker one.
Title: Re: D14-4 Gearbox assembly
Post by: trophy on 09 July, 2021, 20:19:29
Hello Dean.  I do have a gasket fitted but I will double up on it and see if it makes a difference.  Will let you know if it eases the situation.  Watch this space. 
Title: Re: D14-4 Gearbox assembly
Post by: trophy on 12 July, 2021, 21:12:36
Hello all.  I doubled up on the thickness of the gasket on the cover Dean but it made no difference to the kick start lever occasionally jamming so the  gasket stays standard.  However after re-placing the rear wheel chain, and when the lever next jammed I selected a gear and the lever freed once the rear wheel was turned slightly.  So that's how it going to be.  Thanks Adrian.
Title: Re: D14-4 Gearbox assembly
Post by: bluebell on 09 August, 2021, 19:31:00
i have an answer for this .since all the cases are now 50 plus years old now,,this is what you do,,,with the quadrant in your hand,,gently grind off a small amount on the first tooth surface so it dosnt over engage into the chainwheel  cog ,,just a small amount,,this is due to the wear in the starter shaft boss hole becoming slightly elongated,,,and and and  when you kick the engine over,   kick rearwards and down,,,not just downwards,,,,,cappiche?