Gary Britton's  "Fifth" BSA Trials Bike build.


This time Gary starts from Scratch.




Build Story below...



Gary Brittons “Number five”.


Hello Charlie, thought i'd drop you a line about number 4. Actually that should be number 5 as there is also a 

1971 b25t in the garage now, but that’s another story. 

I always fancied making my own trials frame so this

Winters project is sorted.

I stole the dimensions off your site and off the Faber Mk1.

I drew the frame out on

the dining table and set about making a jig.

I used some 4 inch box for this (should be rigid enough). 

For the frame I used 1 3/4 inch for the top tube, 2 inch for steering tube and inch for the sub frame. 

All 2mm wall, I know that’s a bit thick, but it was easy to get hold of and should be easy to weld.

The steering head has machined inserts for tapered bearings.

The swinging-arm is off a BSA B25 all the way from

the USA.

I made slugs to lengthen it by 1 inch to make like the competition swinging-arm it was sold as. 

Well that’s as far as we have got.

I'll keep you informed of progress. By the way, bikes 1,2 and 3 are still going well...


Nigel is winning everything on Mk2, Jay rides Mk3 now, and then (he beat me on the weekend) and I’am still wobbling

around on Number One.




Like the barrel Gary.


All Photos Courtesy Gary Britton.

Yes Always build yourself a jig.



Good Swinging arm box Gary.


A tip to others contenplaiting building their "Otter" Frame,

is dont make the swinging arm to shallow or the  swinging arm will have restricted movment, and if you build it too wide, that many people think the Faber one is, you will have trouble with the chain fouling the top and bottom of the box.




I this one will just be Ok...

Looking a bit like a "Bariel" build to me Gary.




Hmmm, the primary drive is going to be interesting then?




Are that's better but it is still a square barrel Gary.?



B25 barrel C15 head




Explanation from Gary,

Your right Charlie, that cardboard box will never work, so I got one of these.
Only problem is I wanted to use a C15 cylinder  head.
First problem, the valve drain holes are different, so I had to make up a plug and drill a new one.
Problem number two, how to seal the push rod tube, umm.
Problem number three, how to make it look a bit nicer.
Oh well it would not be fun if it was easy.
 Charlie> Your doing a good job, keep "plugging" away.




Faber "Bariel", Frame, this one for a Triumph Cub engine...


An "Otter" frame with longer top tube Like an Ariel HT frame.

And 1" top suspension struts.


 Hi Charlie. Thought I'd give you an update on number 5.
As you can see the basic frame is welded.... Of sorts, (i don't think the Harris bros will be on the phone any-time soon).
All the angles are close to what I wanted and there is not to much distortion.
The steering head bearing seats have gone a little out of round but I think I can fix that with the dremel.
 The swinging arm has rubber bushes so the next job is to make some proper ph-s bronze jobbies. Some nice aluminium 14" shocks are on the way.
The plates under the engine in the pics is just an engine stand, i'm going to extend the engine plates front and rear down below the motor so I can fit a nice 6mm bash plate.
The motor is a B25 with a C15 head.
I know lots of people use B25 barrels on a C15 and i'm not sure how this is going to pan out.
As well as the drain hole not lining up the studs are to short and the C15 ones, are the wrong thread.
I have made a  3mm compression plate to take some of the bark out of it and someone suggested using C15 cam followers to make it a bit softer. But that's long way off yet. All for now G.B.
All Photos Courtesy Gary Britton...
And the Barrel named "Shawn"...
The "Bariel? build, is looking good Gary.
 Hello Charlie, as you can see its nearly finished, not.
This weeks problem has been the exhaust system.
First take one perfectly good very shiny very expensive chromed exhaust pipe and cut it up with the angle grinder.
The fit of the pipe in the head was like throwing a nail bar into a empty warehouse.
First I had to machine the port so its round then turned a plug to take up the gap, looks aright I think.
For the silencer this time I thought I would buy one at the show but when I got it home it just did not look right so this one was bought on ebay.
Some Triumph Tiger-Cub hubs were bought and cleaned up and made wider.
I also made some brake pivot cams.
Forks are four-stud as per the others.
I think the material used for these yokes was more cheese than aluminium, also all the tooling must have been worn out as the burs around all the machining was really bad.
Charlie.> Gary I am just getting some New yokes made as they are getting imposible to find now and the price you have to pay is up to New billet ones.)
As you can see the rear mudguard and seat have that Ariel look about it.
Do you think it needs a brace across the  mudguard?
While asking for advice what about bracing for the swingarm box?
Charlie.> Gary you could rivet a alloy plate on the underside of the mudguard this would keep the look but make it stronger.
Swinging-arm box should be OK with the large diameter tube, but you could brace the footrests to the engine plates which would strengthen it and the rests!
All for now. G.B.  
'BARIEL'S ' I do like its basic design.
The exhaust modification looks very good, a lot better than the standard push into the cylinder head that always leaks.
This hub modification by adding 1 1/2" into the width is a must for good spoke line with the off-set you need.
And still works out cheaper than buying "Billet hubs" if you can do the work... 
You can turn these brake cams on a lathe and then cut and file the flats, so you dont need a milling machine.
All Photos Courtesy Gary Britton.
More Photos and update later.
Charlie~Oo>...Its been some time but Gary has been like me very busy,
 but the number "5" build is now on again, new photos below.
Hi Charlie, a bit of update on number five.
Its been a while but I've not been doing nothing, there's a BSA  B44
that needed sorting, a B45t (B25 with a B44 motor) that now go's like the clappers, but wont stop so good.
There has been a Trimph Tiger-Cub trials bike for a mate, and a garage extension so you can see I do have an excuse.
So on with number five:-
As you can see its off the sideboard and up on its own two wheels.
Still in the dry-build stage.
I made up a cradle as before and got the best welder in the world to stitch it together for me.
(Rally-Weld Pontypool). As it is, it measures 53 inch's wheelbase,
11 inch's ground clearance and
65 degree fork angle, so not far off.
At the moment the shocks are borrowed off one of the other
bikes, and I have 400mm shocks on order so that should raise the thing up a little. I shelved the idea of
using a C15 head when a B25 head fully rebuilt popped up.
But like I said before, this gives me the problem
of connecting to the carb. The carb is pointed straight at the down tube,(I had the same problem Gary)... so I made up a manifold in two
parts and connected them with some hose. It looks a bit convoluted but its the only way I could think of.
With the B25 motor being a bit hot for trials work, I'm trying to soften it up a bit. I made a compression
plate and I'm thinking of using a small carb (22mm). What do you think?
(Yes 22mm sounds good)...
Next job, clean up the welding, pressure test the frame/oil-tank and get the thing painted.
Then I can start
the build proper.
That's all for now. I promise the next update wont be so long coming.
All the best G.B.

GB Number 5...



GB5 ... Side 2...



That is class welding Gary....



Charlie...That is a one of the better ways I have seen getting over the carb line problem without doing the head modification that I did. I made four  manifolds up and could still not get one too my satisfaction Gary, so good job...



More later with the rest of build number Five......




I must say that Gary inspires me every time I look at a new photo that he sends me.

 He is just an artist with steel and aluminium ... And we know he creates great end products, with the bikes that he builds, but there is also this artistic element to the builds that only a true craftsman can achieve...

This country is full of artisan constructors that get little recognition to what they achieve.

 But Our Gary is one, that I will always portray as being one of the best...

 Keep on doing what you are best at Gary creating unique trials bikes.



Only the best gear on These builds, but the best always shines through...



This is the updated build of Gary's Bariel... I do like the intrusion of the Ariel Engine in the shot...



Do You know I feel that the simplicity of the chain tensioner here is the way to go... I have been tying with this for a while...

 Thank's Gary, nice one...


By the first of December 2019, Gary had got number five up and running, and spent a couple of hours testing the bike, another "First-Ride"...

 Here is what he said...


Hi Charlie, Spent a couple of hours riding the bike today for the first time. It works well but the carb is not quite right. The tick over is erratic and the engine speeds up on a closed throttle sometimes, it also coughs and stalls sometimes. Never had these problems on the other bikes.The carb is a 22mm set up for a C15. I know the B25 should have a bigger carb and I think the long inlet tract may be a problem. I know some people say to use another make but I want to use an Amal. Any advice would be most welcome. Cheers G.B.


 Hi Gary…


 Bikes looking good…


 It sounds like it might be sucking air in somewhere on the inlet tract…


It is one of them things with a new build you just need loads of time to get them running right.. Hey…


 I have a B25 engine in build and have not altered the inlet manifold like I have on the others so I will probably have the same problem as you…


Let me know how you get on and what you did to cure the problem…


 Nice to play with another new bike though…..


 Will update page….


 Thanks for sticking with me all of these years too…


 Regards Charlie.


Gary's Number Five....



There is a New Page in Construction about The labelled "Bariel" Machines.


Due shortly.



More Later.