Electric Start For Vincent

[Peter Holmes]

Even so, they will have same old bevel drive to the camplate I´d think. Same with the Surtees 5-speed gears. I don´t have war with the G 49 alu bit - when it does not double with the gear change stops for not over- or underselecting gear change. It is just not great wanting to stop the mass of the actuating arm in the action at the very close grub screws in the G 49 near the gear lever shaft. Too much force there and no reliable positioning at the G 59AS change speed pawl place at that distance from the lever stops.
When deciding on lever stops at the G 49 and grub screws you want that G 49 to be put absolutely solid at its place. So then another flaw with the two fixing screws , one of them the excentric G 57 stop plate adjuster. My memory is clouded about some poor fits of the old excentric screw on the G 49, did not look solid or reliable, rather mangled bits. So , well, another devation, had some plates for the two screws made, plus a separate excentric roller, no hex head on it. I don´t do fine adjustments here, only centralizing the lever roughly for middle position. Then do the non-excentric screw up, throw in the excentric roller plus a split washer for some preload on the roller so it does not move when the lot is finally fixed for good.

Vic
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Vic, I do not think there is any doubt that you are a brilliant engineer, and your analysis and solutions to the perceived design flaws of the Vincent motorcycle are always interesting and informative.

My point being that Ben Kingham (and Tim) are also doing something quite remarkable on the track with a Vincent Black Shadow, Ben competes with the very best that Classic racing has to offer, and often wins.

I don't know how many gears Ben is running, 4 or 5, certainly not as many as a Suzuki RK67 that ran 14 gears to keep it in a very narrow power band, but whatever Ben is running, I would imagine that even with the abundance of torque that Ben has at his disposal, he is still having to make plenty of gear changes to compete with the opposition, with no margin for false neutrals or missed gears, so despite your reservations with regards to the efficacy of his modifications, they appear to function reliably, and exceedingly well.

 

[Peter Holmes]

I think that would be hard to do by me with just a drill press. I'll muddle along with my standard setup.

I would imagine that is what Tony Rose did!

 

[greg brillus]

Just carrying out my 4th Norvin twin with the electric start conversion........just a tad more work than a stock twin though.......

 

[DanQ]

I think that would be hard to do by me with just a drill press. I'll muddle along with my standard setup.

Hi Bruce, This is a mod that my father has carried out on many vin gearboxes he has worked on, he supplied the Kinghams with the modified G49 i believe. There are bikes out there that have covered tens of thousands of miles with this setup, our racers have used it for 30+ years. The block just needs machining to make space for locknuts and a couple of tapped holes for grub screws adding. I can provide a sketch if you're interested?
Cheers
Dan Quirk

 

[bmetcalf]

That would be very interesting! Post it on the Forum, if that is OK, please.

 

[Peter Holmes]

Hi Bruce, This is a mod that my father has carried out on many vin gearboxes he has worked on, he supplied the Kinghams with the modified G49 i believe. There are bikes out there that have covered tens of thousands of miles with this setup, our racers have used it for 30+ years. The block just needs machining to make space for locknuts and a couple of tapped holes for grub screws adding. I can provide a sketch if you're interested?
Cheers
Dan Quirk

Dan, I think we spoke in the Paddock at Brands Hatch (were you the passenger on that day? Lansdown Cup 2022) I was mightily impressed with the outfit, in the pits and on the circuit, your Dad's gear change mod appears to work really well!

 

[DanQ]

Dan, I think we spoke in the Paddock at Brands Hatch (were you the passenger on that day? Lansdown Cup 2022) I was mightily impressed with the outfit, in the pits and on the circuit, your Dad's gear change mod appears to work really well!

Could well have been, i was riding there that year with my passenger Dylan. Cheers, it's an ever developing project, although we can't take credit for the gear change on the kneeler outfit! It is built around a chopped motor with a TTi XHD 5 speed gearbox.

 

[oexing]

Peter, whenever I am faced with shitty components and ideas I am very quick with throwing them out the window before even starting on modding the shit for some improvements. And in this particular case I did not see the grub mod a solid solution, the gear shift stops should really not be at that place for reasons I have posted above. Sure, the alu block will take a bit more time to fabricate as compared to grubs and all. But it is a once for all time thing and robust in all respects, no adjustments even after repairs anywhere. The grub mod is known here for some time already, I don´t remember if I came upon it before I decided on my alu block at the change speed pawl place. Still not convinced about the grubs . . . .

Vic

 

[Peter Holmes]

I would not even attempt to convince you Vic, I would not be qualified to do so, you are without doubt an engineering heavyweight on this forum, I was just making the point that however the grub screw mod is viewed, it certainly seems to function very well, as I am sure your mod will, when it is fully road tested.

 

[LoneStar]

I may be uniquely lucky, but I never seem to miss shifts with my original, poorly-designed shifting mechanism...