Electric Start For Vincent
- Thread starter hernandez1942
- Start date
I had my electric start fitted by Francois Grosset at his workshop in Northern Brittany, France, Francois is the designer (in part) and the manufacturer. His advice to me when he fitted it was not to use the decompressor, to me that is counter intuitive advice, but I adhere to his advice, but my bike is standard capacity in standard Shadow state of tune, the starter has always performed faultlessly, whether that would be the case with a big bore, high compression engine I am not so sure, it was not really designed for those type of engines.
Last edited:
The starter kits work very well.......but on a super tuned up twin, or a big bore high comp engine, the starter will struggle........it is a big compromise and cranking the engine from the opposite end of the gearbox mainshaft is less than ideal.......I see no harm in using the decomp to assist in the start.......it is really more if the engine has not run for some time and the lower crank case is full of oil......this extra drag puts extra strain on the starter just like it slows the crank when you kick start with your leg. The issue with a Norvin is there is very little space on the handlebars (clip ons) for a valve lifter lever.......Some of the ones i've done had the late model TPV heads on with the ability to fit a 12 volt solenoid type Harley decomp valve in each head.......this was a simple matter of a horn type push button on the bars.......Another good mod that I am doing to my own Norvin twin build is to machine a second plug hole on each head and install a pair of the Royal Enfield (India made ones) decomp valves.....these are a very simple cable operated poppet valve that can be hooked up together via one of the one into 2 cable spliters like originally used for the throttle on a twin.......They are quite cheap to buy and readily available.......with the 2 hooked up to a small lifter lever on the bars, it takes up very little room and is very easy to operate, much less effort than the original valve lifter set up.......one finger job.......I did this exact same mod for a new build Vindian project I have just finished for a customer in Victoria.......this is a kick start only bike but the decomp set up is the same as described......works very well and takes up no room on the bars. I first used these valves on a special build twin I did for Ian Boyd in Western Australia years ago.......this was primarily a post war "B" twin but the engine was a pre war bottom end and post war top end.......with this engine there was no decompressor mechanism in the engine at all.......so the use of these type valves was the only solution. I was amazed at how good the set up worked, it made starting the engine an absolute breeze, and this was using the pre-war Burman gearbox with the normal short kickstart lever........all good fun.
The bit I like about RE decompressors is that you can adjust the rear to open first that way you can differentiate which compression you are on with a kickstart on the Comet electric start I still position the piston before pressing the button (I have no decompressor on the Comet)
I recently read in the other VOC mag (fishtail) about where the piston shold be before kicking (a single) it should be just as the inlet is opening I guess thats why it is said for a Vincent "just over compression on the rear" that would be about right fotr the front cylinder (giving the longest swing)
I recently read in the other VOC mag (fishtail) about where the piston shold be before kicking (a single) it should be just as the inlet is opening I guess thats why it is said for a Vincent "just over compression on the rear" that would be about right fotr the front cylinder (giving the longest swing)
It was indeed Martin Quirke that offered the grub screw in the G49 solution to our over selecting problem, and it has worked well, although it did go out of adjustment after about a season of hammering, at least it could be easily adjusted again.
BUT, I don't think this mod will work with the Grosset electric start, because of the modifications needed to the G49. It needs a good portion of the lower removing to clear the sprag clutch, which is right where the grub screws would go.
BUT, I don't think this mod will work with the Grosset electric start, because of the modifications needed to the G49. It needs a good portion of the lower removing to clear the sprag clutch, which is right where the grub screws would go.
The version by Mark Cooper has std cases , but unlike the German one , the starter motor from a car is mounted in the rear of the cases . Mark has given me some dimensions of the starter ring outside diameter which will , he says , fit inside the available space . In essence he has used a Suzuki clutch nested inside a belt driven carrier and worked it all out from there . Beauty is it contains a radial springed cush arrangeent . So if you have a reasonable lathe most of the parts can be made in the shed all apart from the cutting of the belt profiles and milling the spring pockets { vert mill ] . My effort is still work in progress as I now need to set the width of the starter ring gear , then have the tooth form from a starter motor cut to the periphery . This is all going on whilst putting together a Norvin so its not a stand alone mod to an existing bike . From his video Marks starter looks the way to go and does not cost the earth
Just answering my own question , got his address , wrote via a Google translation , but have not received a reply . Can now safely assume that this line of enquiry is now closed and will press on with the Mark Cooper design
Any details ?
No I just read the description in an article on the Irving Vincent it does sound interesting