Converting a Comet into a Twin.

lvhrd

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Not to hijack this thread, but what kind of costs would be involved in building a Comet motor from the cases? Is it even possible to acquire all of the necessary parts?
I ask because I'm thinking that starting with a set of cases (or thereabouts) might be how I get my first Vincent.

thanks,
Chris
 

nkt267

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but what kind of costs would be involved in building a Comet motor from the cases? Is it even possible to acquire all of the necessary parts?
Start by finding a good set of secondhand cases.Then look for a nice Comet that someone else is selling.It is usually a lot easier and cheaper to 'build' a bike this way. As far as I can tell all other parts are available for a Comet ENGINE.Frame parts may be a different kettle of fish.
http://www.vintech.co.uk/
http://www.vincentspares.co.uk/shop.html
Try pricing the parts from these sites...John
 

MartinRestorer

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Comet to twin

I started the thread as I was looking for advice, Russ, Peter & Stuart have enabled me to make a decision. You give me the impression that your toys were being launched from the pram :D

Mark
I have been trying to acheve what you are contemplating, but taking a comet engine from a Rapide frame and building the twin engine.I have been doing battle with some John Wyatt cases over the last 2-3 years with many obstacles. But I may have been unlucky with this set of cases. But good for a chalenge. O and what was your decision.Good luck Martin
 

Comet

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Mark , is it just for the power difference that you are looking to convert to a twin? If it is, a cheaper option than the full twin conversion is the 636cc rebore.:D I am not sure of the full details but there was one at the Severn rally. It still looks fairly standard but it puts out power that is comparable with a twin. It would certainly be a LOT cheaper and so much fun pulling up beside a Rapide and leaving them stood at the lights, after all there would still be a big weight advantage.:cool:

cheers

Comet
 

Mark Fraser

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Mark , is it just for the power difference that you are looking to convert to a twin? If it is, a cheaper option than the full twin conversion is the 636cc rebore.:D I am not sure of the full details but there was one at the Severn rally. It still looks fairly standard but it puts out power that is comparable with a twin. It would certainly be a LOT cheaper and so much fun pulling up beside a Rapide and leaving them stood at the lights, after all there would still be a big weight advantage.:cool:

cheers

Comet

Comet,
I've heard of this recently when I was down the ACE one evening. This chap seemed to think it was Bob Dunn that did this conversion?
Anyone on here had this done to their Comet?
 

Comet Rider

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Big Bore Comets

Hi Mark,

In regard of big bore/ stroke Comets.
I run one of Vinparts 90mm bore kits, my dad runs a Terry Prince 600cc kit. Both go well with either standard stroke, or Bob Dunn 100mm stoker cranks.

If you want more info, drop me a line..

Neil
 

van Ginneke

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Hi all, searching the forum for info on 'who makes new twin crankcases' I found this thread.
(Yep, 3 years later.....) I am toying with the same idea to convert (...) a Comet into a Rapide, I have two Comets.
One in process of renovation and another one 'as found' after 35 year in a shed.
So I can butch one....
The best place to get a twin crankcase is Godet?, but I thought he only sells these if he can build a complete one for you, is that so?
Vincent
 
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