gear ratios

Information relating to the Matchless G5 or AJS Model 8 350cc Lightweight
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klaus
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Joined: Fri Dec 05, 2014 5:29 pm
Location: england

gear ratios

Post by klaus »

hi can anybody tell me if I can fit a gear box sprocket with more teeth to make the gearing on my model 8 higher as it seems to be reving at 50mph and first is so slow,thanks klaus
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Janet
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Re: gear ratios

Post by Janet »

Yes, several people have done this. If you search through this section of the forum your should find a number of posts about this. I believe they put 20T.

I like high revving engines because it makes me think I'm going fast. :rofl:
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Rob Harknett
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Re: gear ratios

Post by Rob Harknett »

I think the manufactures geared the machines to protect them from labouring. I would not consider I would know better than the manufacturers. Unless I needed to change the use, for which the machine it was built. Even then, follow manufacturers recommendations.
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ajscomboman
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Location: HAMPSHIRE UK

Re: gear ratios

Post by ajscomboman »

Having had a model 8 I can say Rob, the factory were wrong! It's so low geared on the 18t sprocket that 1st gear is a waste of time. Being on the larger side 20t was too big but 19t I found to be ideal especially with the trick twin piston I fitted. Went like a bat out of hell even 2 up!
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clanger9
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Re: gear ratios

Post by clanger9 »

I second that: my li'l 250 has an 18t front sprocket and it's undergeared. You can get 19t or 20t sprockets from Andrew Engineering.
More info in this thread here
1989 Moto Morini Dart 350
1993 Ducati 750SS
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Rob Harknett
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Re: gear ratios

Post by Rob Harknett »

I have not had a 350 lightweight. I have had 250's Inc prewar 250. Both seem very low geared in 1st. However the low gear was needed 2 up on some of the steep hills encountered on the Wrexham Jampot run into N Wales, also at the 1992 Jampot at Towcester. Against the very strong headwind on the run home 2 up, I had to drop down to 1st gear and about 10 mph, the bike laboured in 2nd.
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ajscomboman
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Re: gear ratios

Post by ajscomboman »

Rob Harknett wrote:I have not had a 350 lightweight.
Well why did you answer the post then stating that the factory surely couldn't get it wrong. You've got stacks of knowledge but please stick to what you do know to be fact.
klaus
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Joined: Fri Dec 05, 2014 5:29 pm
Location: england

Re: gear ratios

Post by klaus »

thanks to you all I think I will go for a 20t front sprocket cheers klaus
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clanger9
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Location: Chester, UK

Re: gear ratios

Post by clanger9 »

klaus wrote:thanks to you all I think I will go for a 20t front sprocket cheers klaus
Good stuff. Do let us know how it rides with the 20t sprocket. Inquiring minds want to know... ;)
1989 Moto Morini Dart 350
1993 Ducati 750SS
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