Burman gearbox cover

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nickbenson
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Burman gearbox cover

Postby nickbenson » Fri Aug 16, 2019 5:41 pm

Hello folks could anyone offer any advice on reassembling the gear box cover on my 1937 vh. I get the kick start pawl in place and as I offer the case up to the other half then the gear selector mechanism drops out of line and starts to separate. I have had loads of tries at doing it this rainy afternoon but it still won't have it, so Ive come back from the garage now before I go mad. I thought that tomorrow I would try wrapping the selector parts together with a rubber band on a piece of string then when the case is almost home I'd snip the band and pull it free. Most grateful for any advice. Regards Nick

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paul.wirdnam
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Re: Burman gearbox cover

Postby paul.wirdnam » Fri Aug 16, 2019 7:22 pm

Nick, are you doing this with the box in the bike...or on the bench?
'28 Model B (future project), '30 Model F, '31 SF31, '35 4F, '38 VB (abandoned project), '39 4G (current project), '46 VH, '48 KG

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Re: Burman gearbox cover

Postby nickbenson » Fri Aug 16, 2019 7:31 pm

Hi Paul
Yes on the bike. Regards Nick

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alan.moore
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Re: Burman gearbox cover

Postby alan.moore » Fri Aug 16, 2019 8:56 pm

Nick,
Take the gear lever off and assemble the complete gear selector mechanism into the gearbox. (Make sure the two 'dots' on the camshsft gear and the pawl are in line at 9 O'Clock) Then wind the kickstart spring up with the kickstart so its pawl clears any obstructions inside the case and then slide the outer case on.
Have a look at the Youtube video, its for a CP but the procedure is the same as the BA



Come back if your still having problems

Cheers
Alan
1939 VH Redhunter;1942 RN WNG;1951 Triumph 6T Thunderbird;1970 BSA B175 Bantam;1986 Yamaha SRX600 single
http://cloggymoore.wix.com/triumph-pre-unit-6t

nickbenson
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Re: Burman gearbox cover

Postby nickbenson » Sat Aug 17, 2019 6:47 am

Hi thanks for your replies. Yes I watched the video before proceeding and several times since to see if I had missed anything, but with a bench assembly gravity is helping to keep the machanism in place as the gear box is almost on its back so to speak, my problem is that because its on the bike and vertical the gear selector parts are wanting to slide out of place and separate after they have been placed, and the splined shaft for the gear lever is then misalined having slightly dropped, then when I offer the cover up I have to poke a finger through the gear shaft hole in the case to tease it up into line, at this point the whole thing seems to start to separate and the plate on it drops down...thats when the swearing begins again. Short of laying the bike over so that gravity would help me too I thought that I would try to band the parts together with a rubber band to stop them wanting to separate and if I have a string on the band, once the splined shaft is in the hole and the cover is nearly there I then cut the band and whip it out. sounds like a plan. hopefully. Regards Nick
Last edited by nickbenson on Sat Aug 17, 2019 7:39 am, edited 1 time in total.

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paul.wirdnam
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Re: Burman gearbox cover

Postby paul.wirdnam » Sat Aug 17, 2019 7:07 am

paul.wirdnam wrote:Nick, are you doing this with the box in the bike...or on the bench?


Nick, the reason I asked is because I've done this many times on the bench with the gearbox being held in the vice by the mainshaft clutch bearing surface with open box facing upwards. In this situation, it just a matter of assembling all selector parts in the box as Allan says and then lowering the cover on...

,,,but on the bike, you'll have to do the same but you'll have to counter the action of gravity of the 4 spring selector box which will want to tilt downwards. It needs to be horizontal as you put the cover on otherwise you'll never get the pin on the inside of the cover locating in the slot in the spring box. I'd use a thin knife or steel rule to hold it up as you put the cover on.
'28 Model B (future project), '30 Model F, '31 SF31, '35 4F, '38 VB (abandoned project), '39 4G (current project), '46 VH, '48 KG

Paul

nickbenson
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Re: Burman gearbox cover

Postby nickbenson » Sat Aug 17, 2019 8:05 am

Thanks again Paul I will heed your advice and I think I will give it another go this afternoon.

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chris.shearwood
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Re: Burman gearbox cover

Postby chris.shearwood » Sat Aug 17, 2019 12:06 pm

I've used the string method successfully a few times. I don't remember any need for a rubber band, just a string turned a few times around something convenient above and towards the rear (of the bike), then looped down over the gear change mechanism and then back up and towards the front and tied around something convenient. Once the outer cover is almost all the way on just undo one end of the string and pull it out.
1946 4G, 1950 NG and 1951 VH

nickbenson
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Re: Burman gearbox cover

Postby nickbenson » Sun Aug 18, 2019 7:20 pm

Well the string/rubber band plan worked a treat. The rubber band keeps all the parts together especially the outer plate which kept popping off and dropping, when you want to remove it as the case is nearly home you just pull up the string to expose the band then snip it and ping its out.
So thanks again for your help. Regards Nick

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chris.shearwood
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Re: Burman gearbox cover

Postby chris.shearwood » Mon Aug 19, 2019 1:01 pm

Nick,
I'm glad you succeeded but your mention of the outer plate popping off makes me wonder if you had all these parts nicely greased before installing them.
Regards, Chris
1946 4G, 1950 NG and 1951 VH


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