Hello to all,
Just joined and don't know a lot about trails stuff I'm afraid.
Bought a C15 with B40 engine and it's has an 11 front and 48 back sprocket set up. Not sure about the gearbox itself.
Obviously it's impossible to use on the road which is what I'd like to do mostly with the odd green lane and field thrown in.
Any ideas for the easiest way to get it more rideable? Just change the front one maybe? And to what size? Or can I do something with the rear one (bit doubtful this would work though?)
Apart from various other bikes I do have a standard C15 too.
Many Thanks
Adam
As you have a bolt on rear sprocket, bolt on a smaller one that will raise the gearing. You will have to shorten the rear chain as well.
Thanks for the info. How small do you think I should go considering mine is 48 at present?
Why not look to see what the gearing is on a B40. As you have a B40 engine in a C15 frame. Have you got B40 or C15 wheels. I believe the C15 had smaller wheels that would further lower the gearing.
Thanks for your help. I'm aware of wheel size and that a smaller rear sprocket would help, appreciated.
I think my question was that as the front sprocket is 11 and quite a lot smaller than standard then is there any way of re gearing the bike by just changing the back one or am I kidding myself that I can get away without changing the front.
Pretty sure I'm going to have to change the front but seeking a gearbox guru incase I'm wrong.
If nothing else you've got me into the workshop to have a go at it, cheers.
By fitting a smaller rear sprocket you will raise the gearing. Count how many you have on the rear then see what is the smallest available. This might save you pulling the bike apart.
You should have a 19 tooth gearbox and a 46 tooth rear sprocket it might be easier to change the pair to get it right.
Shall do, thanks. I think it's likely I'll be pulling it apart though with 11 front and 48 back at the moment. Thanks for all your input.
:) :) :) :)
If, as Idie says, you should have 19/46T that is approx 2.5:1.
If you wish to obtain that gearing with 11T on the front My maths says you will need to go to 27 or 28T on the rear.
My maths have been suspect for a long long time. So I shant object to going down in flames.
Mike 8) 8) 8) 8)
Thanks for the Maths Mike. Might be worth investigating to see if it can be done on that rear hub before I take everything to bits.
If it all goes wrong I at least can blame you........ ;D
I don't think you can go that low with the bolt on sprockets.
Quote from: idie on 06 Jan, 2022, 12:31
I don't think you can go that low with the bolt on sprockets.
I don't either. :( Apart it comes I'm sure. Something to start on this Sunday.
Hi,
When I had a B40 with off road pretensions I kept the standard rear at 46T and used a C15 17T gearbox sprocket. The gearing was still very useful on the road but gave a bit more plodding ability on gentle off road terrain.
Dave.
Quote from: DAVE BRADY on 06 Jan, 2022, 15:10
Hi,
When I had a B40 with off road pretensions I kept the standard rear at 46T and used a C15 17T gearbox sprocket. The gearing was still very useful on the road but gave a bit more plodding ability on gentle off road terrain.
Dave.
Now that might be perfect as I've got a 48 on the back, so if I'm right then a 17 front might give me the best of both as I'm not looking for fast road use.