BSA C15

[scot taco]

A friend of mine is selling a 250 BSA in street trim.How much work and money would it take to turn it  into a trials mount? Can the frame and engine be used in standard trim? 

[totalshell]

months a lot and a lot should cover it.. simply the most expensive way to aquire a p65 bike by a significant margin.. all that would be useable would be forks frame engine..and all three would require modification.. and you d then end up with a converted road bike. buy a drayton frame buy an engine then buy everything else you would have had to buy to modify your c15 and you ll have a proper trails bike.

[cleanorbust]

As totalshell infers the sky's the limit when it comes to buying parts (some of them major, like wheels) to convert to trials trim. Really depends on what type of trials bike you're looking to create. If it's a reasonably competitive one, you'll be in for quite a lot of work and expense. If you just want a bike to ride for fun (though it might not provide much) you could just do a light conversion but end up with a bit of a lump and, sadly, spoil what might be a reasonably nice road bike by trying to turn it into something it's not.

Edited June 28, 2017 by cleanorbust

[scot taco]

Thanks for the replies. I was thinking maybe put some Betors on front,change gearing,seat and tank,but I kind of figured there was more to it than that.

I would like to own a BSA at some point,but not a road bike as I wont street ride anymore.

 

Thanks again.

[2stroke4stroke]

I would let it go to someone who would appeciate an unmolested roadgoing C15; there's enough bikes being cannibalised as it is.  

As you don't seem to be in a hurry you should be able to find one that someone else has converted or part converted leaving your conscience clear.

[japes1275]

Er, surely if scot buys a Drayton frame and a load of modern bits he'll end up with something totally different to a proper pre65 trials bike?!

BSA had a bit of an idea about trials bikes and what they did was convert a standard C15 and turned it into a trials bike - admittedly one that still needed loads of work to make it competitive!!

I agree with what has been said though, it will cost a fortune in time and money, better to buy one already done or perhaps half done?

 

[tony27]

You also forget that all those parts are probably not legal for use in the states anyway 

[scifi]

Used to have an ex works C15 that had a Scrambles frame and engine tuned for trials, for use in the SSDT.

After I used it for club trials, I modified it further to be competitive in Scrambles and Grass Track.   Used a 1 1/16 Amal on Methanol, sprint cam, Goldstar inlet valve and 12:1 CR Piston.   The Close Ratio Gears cost just £15.

So if you want to mod a road bike to trials, there are several things needed changing.

Frame mods to give Ground Clearance at least 8 inches, High Lift Exhaust. Single Seat, Long Movement Forks, maybe modern shocks to extend the travel on the rear.  Proper handlebars and ball end levers.

Then the engine needs the correct low compression, and a mild Camshaft, there is also the Wide Ratio gears to find.  I think these days you would need folding footrests.  Lower gearing cogs gearbox / rear cog     Then to use trials tyres, a 21inch front wheel WM1, and a WM3 18 inch rear wheel, with the security bolts.

Best of luck

I don't know if the frame head angle lugs were different types on all the BSAs models, maybe that's Ok.

Edited November 8, 2017 by scifi
Head Lugs.

[oldaz]

Find Michael Waller on youtube and have a look at his BSA builds, it will give you an idea of what's involved and possibly steer you in the right direction re BSA frames.