• Welcome to the website of the Vincent H.R.D. Owners Club.

    Should you have any questions relating to the Vincent H.R.D. Owners Club, or Vincent H.R.D. motorcycles in general, please contact Graham Smith, Hon. Editor and Webmaster by calling 07977 001 025 or please CLICK HERE.

    You are unrecognised, and therefore, only have VERY restricted access to the many features of this website.

    If you have previously registered to use this forum, you should log in now. CLICK HERE.

    If you have never registered to use this website before, please CLICK HERE.

G: Gearbox Burman Box Again

peter holmes

Well Known and Active Website User
VOC Member
In Australia and the UK we say Maths not Math. Grammar and spelling policeman at your service.:rolleyes:
In defence of the UK state education system neither Maths nor Math is correct, we were taught the three R's Reading, Writing and Arithmetic, I presume the three R's relates to the phonetic spelling, Math and Maths are simply abbreviations of Mathematics, the Americans chose to leave off the last seven letters, the Brits chose to drop 6 letters out of the middle, but tacked the s on the end. UK Grammar and spelling policeman at your service.
 

BigEd

Well Known and Active Website User
VOC Member
VOC Forum Moderator
In defence of the UK state education system neither Maths nor Math is correct, we were taught the three R's Reading, Writing and Arithmetic, I presume the three R's relates to the phonetic spelling, Math and Maths are simply abbreviations of Mathematics, the Americans chose to leave off the last seven letters, the Brits chose to drop 6 letters out of the middle, but tacked the s on the end. UK Grammar and spelling policeman at your service.
The vagaries of language and grammar would appear to be at least as complicated as this thread's topic. Burman Gearbox Again.:oops:
 

brian gains

Well Known and Active Website User
VOC Member
CB: I shall annotate my copy of Stevens on the margin accordingly, thank you.
However, my measurements do differ from yours , again using vernier calipers, my measurements in red.;
FROM CLUTCH END: bearing register on shaft (length), .760" 0.912". Width of 21 tooth layshaft gear approximately .926" 0.909", and the spline length corresponds. From the kickstart end, width of bearing register on shaft .949" 0.889", width of layshaft 3rd. gear .700" 0.700" and the spline length corresponds, (well it sticks out about.005").

Allowing for discrepancy in accuracy of measurement both of our sum measurements would correspond with Richardson statement that " the layshaft is sub assembled with the longer splines away from the operator". This being when mounted in the box. It may be more revealing to say that the bush for layshaft 2nd gear pinion , furthest away from the operator, is 0.783" or longer than layshaft 1st gear pinion bush which is 0.879" long.

Clear 8-/ ?
 

chankly bore

Well Known and Active Website User
Non-VOC Member
As a final observation I have a Newby belt drive on the "Comet on Steroids" with the standard Burman gearbox. Gear selection is light and quite often noiseless.
 

greg brillus

Well Known and Active Website User
VOC Member
I'm not convinced the Newby kits are ideal for street engines, only on account of the hub bearing not being a sealed unit. if the bike is being used quite often, there is a real risk of the clutch hub bearing running dry and seizing in some fashion. When used for racing, you need to strip the clutch and repack the bearing every year or so.........the one on the twin racer, started to grab/pick up because I had nearly forgotten to check it.
 

chankly bore

Well Known and Active Website User
Non-VOC Member
You probably have a point there, Greg. I'll keep an eye on that. I'm more worried about a lack of an E.S.A. I'm thinking of grafting on a rear wheel (Honda) with a cush drive, II'll get better, cheaper brakes as well!
 

greg brillus

Well Known and Active Website User
VOC Member
Don't get me wrong, I think Bob's kits are great, but just not so maintenance free as we might like. I am actually trying to buy a crank pulley off him as we speak..............:)
 

brian gains

Well Known and Active Website User
VOC Member
just to bring this saga to a conclusion, after no end of kerfaffiing about the drama that started with 4th gear disappearing out of the blue, the gearbox casing failing at the drive side circlip retaining groove and then the lurching 1st gear problem having had not a single issue with 1st prior to this. Not suspecting there was anything wrong with 1st and thinking it was an end play issue on the shaft I finally replaced the lay shaft gear, here are the new and old for comparison.

.thumbnail_20200112_153044_resized.jpg
I would say that I inspected for wear and with nothing to compare the failed one with I expected to see wear from the driven side of the dogs only and there was what I thought some minimal wear on the leading crest of the dogs and on the stand everything engaged quite happily however with the benefit of comparison the all over wear seems quite excessive.
I would saythat there had never been any inkling of 1st gear failure and that it would seem that this wear occurred in a nano of a second when the shafts were slopping around due to the mainshaft not being registered correctly. Fingeres X'd only service items for the rest of 2020 and I hope someone at some point can benefit from my experience. ps the young woman who gave me a thumbs up and jumped up and down as I took it for the initial shake down run up the road doesn't know how close she came to getting a big hug and a kiss.
 

Latest Forum Threads

Can't Find What You Need?

Buyer Beware: Fake or Real?


Top