Burman HP Gearbox

[GuyH]

Thanks John, I got you mixed up in my earlier post with John Gleeson who also posted on here some time ago and may have been the person who bought your bike judging by the parts he was looking for. Would I be right in thinking that a set of pre war 350 gearbox plates and a CP or GB gearbox will fix my problem if I can't find an HP box? That would still leave the problem of finding some chain-cases but would be a big step towards getting the bike completed.

[nevhunter]

The VCH's have the back wheel forward of the normal position and the gearbox adjuster nut fits in a hole cut through the rear guard. Cp and BAp gearboxes fit the same size plates. Nev

[GuyH]

Thanks Nev I'll keep an eye open for some VCH plates just in case this is the way I need to go. By the way I had some OG/OH engine and gearbox plates laser cut as the ones on my OG were some bodged up home made aluminium ones. It was virtually as cheap (or expensive depending which way you look at it) to have half a dozen sets cut as it was to make one set. If anyone out there is in the unlikely situation of needing some 1939 OG/OH engine and gearbox plates (for the HP gearbox) just let me know.

[nevhunter]

the vch plates are the same as the normal ones. The question is is the rest of the frame right to fit them to to allow the fitment of the CP box. the big question appears to be is the primary chaincase the same size? nev

[GuyH]

Thanks Nev these are good points. I'll have to compare the gearbox plate mounts on the frame and see if they're the same or if there's scope to alter the plates when I get some. I doubt the primary cases will be the correct length - they're quite short and compact. I'll have to get some plates and have a play with the old Burman CP box I have and see if it can all be made to line up. Hopefully it won't come to this but it's a good contingency plan.....

[brenton.roy]

Hi Guy,
don't forget that some Ariel's of this era (well, slightly before) had a pressed steel primary.
This is an outer only.
Noisy, probably a pain re chain oiling, but still..
Brenton

[GuyH]

Thanks Brenton, I wish it were so with this bike. Unfortunately not. I've uploaded a photo of the cases on my OH 250 - completely different from anything else I believe. If all else fails I may well end up doing what you suggest and using a CP box and adapting a pressed steel one to cover it all. I have a couple lying around which may be suitable. Ironically there are probably HP boxes and OG chaincases lying out there in someone's shed and no-one knows what they fit.....

[brenton.roy]

Hi Guy, well photo's always help. You never know what's lurking around, or whose memory might be jogged...
The steel primary does fit your early style crankcase.
They really are interesting bikes! Such a mix of old and new.
regards, brenton

[GuyH]

Hi Brenton, thanks for the info on the older pressed steel primary cases. I didn't realise they could fit the later models. I've just had a look at a photo of my 1930 model B and the mounting lugs appear to be in the same place plus it has the hole for the footrest bar. I'm working away at the moment but when I get home next week I'll take the primary off the B and offer it up and see what happens. Meanwhile I'll do another 'wanted' post with a different title and include the photo's.....

[nevhunter]

The original is a neat set up. The clutch seems to run"WET". and the primary chaincases appear different. The later W/NG's ran a steel set of primary chainguards but fit the same distances as the civilian alloy ones. You would have to check all centres and mount under the chainguard at the rear underside. This might turn into a fairly complex job., because the frame may have different dimensions somewhere and you don't really want to start altering it.The easiest way would be to get a standard frame and just fit the motor to it with the rest as a 350, and keep all your parts in case the bits you require ever become available. Nev