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Hi all, so I have ended up with a C15 Road bike in my garage ready to convert into a trials bike. I realise that it will never be as good as an Otter or Drayton framed bike but it's all I've got to play with at present. 

So what I want to low is what hubs do I use to get laced to the 19 rear and 21 front rims, do I use the C15 hubs that I have or do I use something different?  

Do I use the C15  forks or enter the minefield of Fork / yoke /wheel options? 

Bearing in mind I would like to maybe upgrade to an Otter / Drayton frame one day. 

Im sure this has been asked to death so sorry for this but I need a shove in the right direction. 

The last bike I had was a Gasgas 300 but I fancied a British 4 stroke project. 

Thanks in advance. 

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15 minutes ago, H123 said:

Hi all, so I have ended up with a C15 Road bike in my garage ready to convert into a trials bike. I realise that it will never be as good as an Otter or Drayton framed bike but it's all I've got to play with at present. 

So what I want to low is what hubs do I use to get laced to the 19 rear and 21 front rims, do I use the C15 hubs that I have or do I use something different?  

Do I use the C15  forks or enter the minefield of Fork / yoke /wheel options? 

Bearing in mind I would like to maybe upgrade to an Otter / Drayton frame one day. 

Im sure this has been asked to death so sorry for this but I need a shove in the right direction. 

The last bike I had was a Gasgas 300 but I fancied a British 4 stroke project. 

Thanks in advance. 

Hello just read your details and would like to correct you on size of rear wheel this should be an 18 inch not 19 and welcome to the bottomless bucket world.  ps am just about to sell an Otter framed B40

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Thanks yes 18 rear, my head is a bit full from so much research and easily confused!  

I fancied the challenge of the full build rather than buying a finished one although I researched alot I only realised the drawbacks of a road frame conversion when it was in my garage on bits and staring at me. Oh well,  I'm sure I can turn it onto something reasonable. 

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Your post really is a "How long is a piece of string" type question. Firstly what shape is the C15 in ? If its a tidy and running bike then it would be a shame to break it up into trials bike as you will end up not using most of it. There are plenty of C15 and B40's parts around, it would probably be better to build a bike from bits. It depends what level you want it end up at,there are some lovely ones around that ride very well and some that are heavy,horrible and don't steer,stop or go very well.

The main bit is the engine,I think its generally accepted that the later roller bearing big end type engine is better. Mine has just been rebuilt by Rupert Ratio himself,(You need his books for any unit BSA) with a Triumph 5ta piston.(About 260cc now) It has Electrex World ignition and WD B40 gears. Thats it,all the rest of the engine is standard, it is lovely to use,as soft as could be,chuffing down to nothing and picking up crisply.A good spread of the first 3 gears and a jump to top as a road gear. You would struggle to find a nicer engine to use for a Pre65 trials bike.

With the frame,you could use a Drayton or Otter, and there are others,all an improvement on the original.Forks again, plenty of choice,mine are the 4 bolt BSA/Triumph ones, not particularly good but better than the original setup. With the wheels I'd straight away go for a pair of Gerry Minshall hubs or Alan Whitton. Lighter and brakes that actually work.

I guess its all about how much you want to spend or not. They can be very nice bikes.

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35 minutes ago, H123 said:

Hi all, so I have ended up with a C15 Road bike in my garage ready to convert into a trials bike. I realise that it will never be as good as an Otter or Drayton framed bike but it's all I've got to play with at present. 

So what I want to low is what hubs do I use to get laced to the 19 rear and 21 front rims, do I use the C15 hubs that I have or do I use something different?  

Do I use the C15  forks or enter the minefield of Fork / yoke /wheel options? 

Bearing in mind I would like to maybe upgrade to an Otter / Drayton frame one day. 

Im sure this has been asked to death so sorry for this but I need a shove in the right direction. 

The last bike I had was a Gasgas 300 but I fancied a British 4 stroke project. 

Thanks in advance. 

Just keep the motor and put the rest on ebay because thats all there is from a road bike thats worth keeping. Oh yes and keep an eye out for a trials gearbox because the road one is not really that good ratios wise. Personally i'd just sell the lot save the money and buy a trials one already done. Much cheaper to do that in the long run. Sorry.

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Ok so it's a 1963 frame on the log book but I don't think it is the original engine so not sure on the age or how to date it. 

Another reason I went for a full bike is to get it Road registered but I'm sure someone will tell me I can do that with bits too. 

I was trying to keep costs low but I was clearly deluded!

Not sure what to do know especially with old trials fantics comment. I guess I've made a rookie mistake.

Ultimately all I was aiming for was a bike I could build myself, enter the odd trial for fun, play in the woods and go to the local for a pint on. 

Another crossroad to decide which Road to take. 

 

DSC_3029.JPG

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2 hours ago, old trials fanatic said:

Just keep the motor and put the rest on ebay because thats all there is from a road bike thats worth keeping. Oh yes and keep an eye out for a trials gearbox because the road one is not really that good ratios wise. Personally i'd just sell the lot save the money and buy a trials one already done. Much cheaper to do that in the long run. Sorry.

What he said. ^^]

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I hope you have the other bits for the bike, not showing in photo! Otherwise either way it’s going to be an expensive project. Someone is looking for a road bike project so it should sell well. As others have said buy a C15 already converted or if you can a genuine C15T 👍🙂 converted road bikes can be very nicely done with all the right parts and then there are the conversions done purely because a trials 4 stroke attracts far more money💷💷💷 just compare the price of a few such as AJS and Matchless road and trials variants, you get more bike for less as a road variant and a lot less bike for the Trials version! I’m still trying to get my head around this price differential as I too would love to have any one of the afformentioned bikes. I had a genuine C15T as a schoolboy, bought for £15 in bits. I took the forks to Valu Motorcycles in Luton for them to rebuild £12. I then sold the C15T on for £35 still in bits. I sold it to a mechanic who had it built up and running within the week and was riding it at Oughton Head Common Hitchin. He then junked his very old BSA 250 with gas pipe home made swing arm and swinging footrests for wheelieing. That bike had external oil pump with adjuster but I can’t remember what Beezar it was but it was old but had knobblies and chrome petrol tank, so some conversions can be quite interesting🤔🤗😳 Pick your bike with care.

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If you really want to build it yourself, do yourself a big favour and check out Michael Waller's video's on youtube before you start.

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Looking at what you have, I think you would be financially better off buying a secondhand Beta Rev3...!

Just getting the gearbox sorted will be a big problem, as you will require the very slow first gear, also even if you can source the cogs, you will also require the Wide Ratio selector forks...   Back in the day, the whole  8 cog-set cost £15,   you won't find one cog for that now.

https://www.bsaunitsingles.com/Archives/Owners_Manuals/C15 Gear Ratio Bulletins 1963 x.pdf

Maybe better to build it up as a road bike, those deep valance mudguards are worth a fortune...

.

 

Edited by scifi

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22 hours ago, brian0304 said:

Can I ask how much are Minshall or Whitton Hubs/ Brakeplates ?

Budget on at least £300 per wheel built up and thats using a good second hand rim.

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The BSA forks are worth keeping, all you need to do is weld a bar on and you have two first class pogo sticks.

The kids love'em :thumbup:

 

Edited by suzuki250
  • Haha 1

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