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Triumph Twin Into A B40 Frame - Any Thoughts?

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Hi folks,

I've just signed up to the forum as I'm looking to build up a bike for green laning and long distance trials. I've got a WD B40 frame and a C15 engine but I'd really like to put a Triumph 3TA engine in (mainly because I love the sound of the twins). I haven't got as far as acquiring an engine yet as I thought it would make sense to check out whether it's possible first.

Has anyone out there done it themselves and if so are there any major issues i.e. will the engine fit the frame without major mods and is it possible to get chain alignment ok without dramatically changing the balance of the bike?

I'm not looking to do hard core trials and it will probably spend more time on the road than off.

Any thoughts and wisdom gratefully received.

thanks

Welcome to the forum. My advice is to get the tape measure out and do it - whatever you end up up with it will be another British bike being ridden.Both the unit BSA and the unit Triumph twins have plenty going on in terms of modern ignition and lighting coils,so getting reliable sparks and lights is easier than ever before - the two biggest problems in the past...

Direct answer to your question is yes as I ride one in trials. It is not a WD frame and I do not know the difference. It is a tight fit with exhausts being a problem.

The triumph adventurer was basically a unit bsa frame, b25/b50 oif with the triumph twin engine fitted in it for trails, green lane work.

I have a TRIBSA with a 500 unit twin engine in a B25 frame. The engine does fit, but the rear part of the LH frame loop has to be modified with a hammer. Because it is all so tight in that area, It is imposible to adjust the primary chain tension without taking the engine out of the frame. Not great!

The side stand needs to be very long, the bracket modified or made cunningly cranked.

i used a Triumph high level siamese pipe from Armours (unchromed) and had to have a new RH exhaust tube made up for it as the std version wants to pass through the frame downtube!

The oil in the frame set up gives you more room to package an air filter/battery/assorted electrics in the space behind the engine. You can also buy competition side panels from Rickman which cover up all this junk.

Overall it is a really nice bike for road and trail.

I would add a picture if I knew how to do it!

I am looking for a folding gear lever for my bile - anyone know a supplier?

Unless you intend to enter trials events I wouldn't bother, if you look how much it will cost to build this up you're much better off buying something like a Honda CRF.

I have a lot of Pre '65 trials bikes and built a couple so I know how much you'll be looking at, you'll be hard pressed to get much change out of a couple of grand and this will buy you a solid purpose built green laner.

As for noise, not sure you can beat the FMF will a mega pipe manifold :-)

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