Primary Belt drive by Bob Newby

Spqreddie

Well Known and Active Forum User
VOC Member
Thanks David,
do you know how many teeths has this front pully in order to know the ratio?
The generator sproket doesnt seems to fully engage, it looks like the theeths might escape and wear the belt, but might just be the photograph perspective.
Ciao,
Edmondo
 

davidd

Well Known and Active Forum User
VOC Member
Edmundo,

It is a 40mm wide belt with a 36T CS sprocket and a 68T clutch. David says the gap at the generator may be a little big and he will close it down with the eccentric adjustment, but he has not had any issues with it.

David
 

Spqreddie

Well Known and Active Forum User
VOC Member
Thanks, so it gives you a 1,88 ratio.
To go near the stock 1,6 rato, you would need a 44 or sproket but as you wrote in a previous post it will be difficult to fit it under a cover, therefore soultion would be as suggested to get a small front sprocket and change the gearing at the back end to compensate.
Any how i think that i would still opt for 44 sproket if it fits without need of grinding the cases to not get to far away from the orginal set up. of course a custom cover will be needed.
Thanks,
Edmondo
 

johnmead

Well Known and Active Forum User
Non-VOC Member
9k=

mm Newby
Here is a picture of a 40mm Newby primary cover being developed by a member of the VOC Dutch section. He has been working on it for a couple of years and is near completion. I have a standing order for one.

John Mead
 

johnmead

Well Known and Active Forum User
Non-VOC Member
Beltdrive Primary Cover.jpg

Here is a picture of the 44mm Newby belt drive cover.

Thank you Bruce, it worked. See you at the next section meeting at seans.

John Mead
 

minivin

Well Known and Active Forum User
VOC Member
Has anyone had any more experience with fitting one of these twin belt set ups, into a standard primary? I am still questioning whether I am willing to run a standard triplex chain, what with the engine I am building hopefully being a bit spiced-up. However, I don't fancy having spaced-out covers destroying the looks of the engine. Has a way been found to hide all this under the standard covers?
 
Top