model B 557 sv gearbox ratio
model B 557 sv gearbox ratio
Hi all, Just got my model B going out for it first long run and its a bit slow in top can I change the front sprocket or what to raise the top speed a bit more than it is ?, it pulls very well up hill surprisingly well for a SV and there is plenty of compression etc., or do I need to change the ratio's in the gearbox, any advice, going by the numbers on the g/box it is a low ratio box, thanks Clive.
- Roger Gwynn
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Re: model B 557 sv gearbox ratio
As standard my B has a 16T engine spkt, I run it with a 21T, which is OK in the low countries but I am taking it to the Black Forest next week and will change to a 19 in deference to the hills. 1st is still not used on the flat unless a quick getaway is required but I suspect that starting in 2nd is quicker as it saves a gear change. But speed is not really the point. Overall ratio is always altered using the engine sprocket, all boxes are 1:1 in top gear. I see in 1927 Ariel quoted 17 or 18, then 21 or 23 in 1928-30.
Roger Gwynn, Membership Secretary, curator of the Machine Register and the works drawings. Director of Draganfly Motorcycles, Craven Equipment and Supreme Motorcycles mostly retired.
Re: model B 557 sv gearbox ratio
Hi Roger, thanks for the information on the front sprockets i will sort that and try a bigger sprocket as you suggest and see how she goes and you are right about first gear its very low. regards Clive
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Re: model B 557 sv gearbox ratio
Hi Guys!
May I ask where I get different sprockets for the Model B?
Regards
Andreas
May I ask where I get different sprockets for the Model B?
Regards
Andreas
- Roger Gwynn
- Holder of a Golden Anorak
- Posts: 1143
- Joined: Tue May 28, 2013 11:34 am
- Location: Norwich, UK
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Re: model B 557 sv gearbox ratio
Depends on the year, which is always useful information. The sprockets changed in 1928,29 and 1930. Certainly later 1946 sprockets will fit fro 1930, not sure about earlier models. I was lucky in that my bike came with alternative sprockets.
Roger Gwynn, Membership Secretary, curator of the Machine Register and the works drawings. Director of Draganfly Motorcycles, Craven Equipment and Supreme Motorcycles mostly retired.
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- Holder of a Golden Anorak
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Re: model B 557 sv gearbox ratio
hi you can try Geoff Brown at the clubs gearbox and clutch parts , or try Drags they may have the sprockets you need
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