Pat Slinn's forerunner of the BSA "Otter".......




 The BSA Otter, has been hidden in the background of the Classic Trials movement for far to long, and has been shunned in some circles as a bike without an identity.

Well now is the time for that to change. We will try eventually, if there is interest, run events for ourselves and have one or two rallies a year,  for like minded owners to meet.

If you are interested.

                NEW Information.


Now that this web site is expanding to incorporate a wider aspect of the Classic Trials Scene.

You will be amazed at some of the articles within the pages now on this site.

 We now intend to build this site into the best Retro and Futuristic, Non Stop trials Information pages on the Internet...

To find out "What is New" on the site and the updated pages that get done on a daily basis,

Go firstly to the current year News page, which is at the top of the listings, where there will be announcements to all that is New on the site...



Pat Slinn's BSA C15 Rebuilt for a second time, and back in the livery it started its life with.



Most competition motorcycles from the BSA Factory were finished with a nickel plated frames.



This is BOK228C as it was first built,but now the steel rims have been replaced with deep flanged alloy.

It was in this guise,but with the steel rims, that Scott Ellis, Won the 1965, British Experts Trial in atrocious conditions...


Then we get To the Now Famous,

 "Foster BSA and Triumph Otter's"...

The frame that started the name for this type of machine...





Harry Foster would be so proud of what he had achieved, by bringing this, so simple a design for a BRITISH motorcycle trials frame affordable to the enthusiasts who then wanted to build up a BSA "Otter"1985.


Well someone wishing to now  build a bike to the same specification today can, as the Foster Otter frame will be back in production shortly, 2016.


A True Classic "BSA Otter".



           Make this year, your year, to do just that.

 Build a BSA "Otter" and use the engine of your choice...

 All the information you will need to build a "Otter" type trials bike like any of these on this web site ... Is here... 

Just take a look, you will get very interested...






to BSA Otter.Com


Site Started March 2010...


On this web site it is my intention to set up a BSA "Otter" Owners Club. And to produce

information about

other owners bikes as well as my own collection. 
There will be articles and information about the BSA (and sometimes Triumph) engines that fit into these frames. 
And it is my intention to run club trials for the BSA "Otter", along with a few well chosen bikes out of the Ariel and BSA factories, allowing some of the superb replica examples that are out there as well to compete, if they wish.
A brief history of the BSA "Otter" name, and frame.
 "My Theory".
Pat Slinn worked in the BSA Experimental/development department part of the competition shop, and in this shop a well known trials rider had his work bench, this was Samuel Hamilton Miller.
Now Pat worked all day next to one of Sam's Ariel's, and there were two both with the famous registration number GOV132. He got to thinking that  he could possibly construct a frame similar to the one used by Sam for his Ariel's, to fit a 250 BSA engine in, we wont call it a C15 because the engine was an experimental one with a beefed up bottom end.
  Anyway, Pat set too with his hacksaw, and started to make his frame with large two inch top frame and seat tubes, which were to carry the engine oil the same as GOV132. And as there were obviously BSA parts to hand,for frames that Pat had  tested, on prototype bikes for the British Army, he knew that the swinging arm and sub-frame from one of these bikes would be more than adequate, for the job so used these.
Take a look at Pat's bike at the top of the page, and in its final reinstated condition on the left.
So this is the bike that he rode in most national trials in the UK from 1964.
 Another person working in the same department was Scott Ellis's father Sep.
And Scott was now a "BSA" works rider, he was also on a quest to build a lightweight bike with more ground clearance.
Pat remembers seeing Scott's frame in his fathers office one day, and also the comp-shops welder George welding brackets onto the frame. But he thinks the main part of  the frame was built outside the factory. The influence was from an Ariel HT and an Elstar grass bike that Scott was riding at the time.
It used a Triumph Sports Tiger Cub sub-frame and swinging arm, So not forgetting that Scott had just moved over from Triumph, where he was a star riding a Works Tiger Cub.
Now this frame turned out to be the final one fitted to his works ride BOK228C, first registered in January 1965. And the frame that the late Harry Foster copied and named The now famous "BSA "Otter".
 But as you see Pat's bike was probably the one that inspired the others. Even the late Brian Martin, Comp shop boss at the time, was given some credit by Sammy Miller MBE, for it's design, true or not, we may never know...
There were others that made frames along-the same lines, as the BSA Otter  at the same time Harry Foster was making his, frames, but do you know where any of these frames  are?
We would love to know.
When we say "Otter" any frame with a silhouette in the same guise, as the original conception of the machine,
would be considered to be classed into this same bracket,
has long as it set out to achieve the same principles, of the frame built by Scott.
IE:To carry the engine oil in the large diameter frame top and seat tubes (2" dia). and to un-cradle the frame tubes, making it a spine type design. with no supporting frame tubes under the engine unit.
A separate rear subframe would be considered more concise with the original design, which has you now know used a subframe from a Sports Mountain Triumph Cub.
But welding this to the main frame would only be considered an update.
As would be using any existing swinging arm unit.
So You see an "Otter" trials machine frame can be in many disguises.

So Check out the many pages and enjoy the site...









And Welcome...














And one thing you can have with a BSA"Otter" is load's of fun! Hey Brian.

Faber Mk 1-2 Frame.

Isle Of Man...

This is Pat Slinn's frame in the raw, after forty five years of service Pat stripped the bike's frame back to bare metal before repainting, and rebuilding it to show standard.

Looking at this photo you can see where the influence for the "Otter" frame came from, and as I have said before, this must have been the frame in the minds of Scott Ellis and his father, when they went ahead and built up their version.


Pat Tells me that he is now in the process of re-renovating the bike again making sure that he fits replacement parts that are necessary, and the same that were fitted to the bike when he originally built it.


Well we now know that has been done.

Look at the top of the page photo...















  More picture of Pat's frame in the stages of build up,  from this shot will be found in the Gallery.


Pat Slinn's Reply, to me about the web site. 2010.

Hi Charlie,
Congratulations on the "Otter" web site Charlie, it really is good.
The story of my frame is about correct. Brian Martin did know of it's existence, but I can't remember if he ever rode it.
Jeff Smith rode it.
 The occasion was when BSA was mixed up with a youth motor cycle project that was held on the BSA "Rec" behind the factory,
( where we all tested and practised on our trials & scrambles machines, and Sammy carved out some amazing sections !)
and Jeff was a special guest on one of the sessions. I only wish that we carried cameras in those days like we do today. I enclose some more photos of my bike.
When I first built the bike the frame was nickel plated, as per the majority of works frames, and bits and pieces were chromed. when BSA sent me to live and work in Germany I left the bike with my twin brother, he used it but unfortunately did not look after it. He worked for a powder coating company so he had the frame etc striped and powder coated. I am at present restoring it back to it's 1964 condition. 
Regards, Pat Slinn.


We then in the year 2000 get a New build of BSA "Otter".


Sammy Miller and Howard Fawkes from HGV Engineering in Cornwall, decided to join forces in a venture to build a New batch of "Otter" frames, using one of the Foster original frames as a pattern for the New Jig.


These became known has the

Faber... BSA and Triumph"Otter"...

And sold mostly through  Sammy Miller Motorcycles Trials outlet, eventually this became known has Sammy Miller Products. 

But some sold direct from Faber Frames...

One hundred of these Faber built frames were sold quite quickly for something from a minority sport. like  "Classic Trials".


Sammy eventually went his own way, and had "Otter" frames of his own made for a while, These were the Sammy Miller BSA Otter's...

There are still some of these that are still used, and can be spotted because of the bolt on sub-frames fitted.


To satisfy the powers that be in the Scottish Pre 65 trial at the beginning of May every year, Howard from Faber Frames came up with a Mk 3 version of his "Otter" frame.

This frame although mostly in the spirit of the original frame now had added engine under-run rails, and a bent spine frame, more like a BSA C15 but of bigger section.


I feel Now in 2015 it is time for a New batch of the Faber MK2 frames and I am going to do my best to persuade Howard at Faber Frames, to build a New Batch

 of these...


Photo Courtesy the late Pete Dawson.


This is a Mk 2 Faber "Otter" BSA built by Dave and his father Pete Dawson who also took the photo.

Thank's Guys...


The BSA Otter.Com. Frames.

After now owning a couple of Faber framed BSA Otters, I decided to have a go at building my own frame.

I started with a replica of the original Scott Ellis British Experts Winning  machine,

Working with only a picture  in the Don Morley book,

"Classic British Trials Bikes".


The Scott Ellis Replica 250 BSA...


I then built the Pat Slinn designed frame for the

"Top-Cat" Triumph TR20 Cub.

Top Cat Triumph TR20 Cub during build up...

After this machine was built using a frame jig that I had made, I decided after a conversation with a friend to see how cheap I could build a "Otter" frame.

This was the

"OOTC" (Otter-On-The-Cheap)

bike below.

Other "Otter" frames were built including one built from

Square tubing, the

"SQ" framed Otter machine.


We now also have the Foster Original frame jig, so that production can restart with these frame to the Original Specification.

If there is Interest...



Photo Courtesy Otterman. "Otter On The Cheap"..

So on these pages there is, as I have said, all the information to go ahead and have a go at building your own machine from scratch, if you wish, and many using this site for guidance now have.


We now in 2016 add a new frame builder to the list of people producing

Scott Ellis Replica frames.

His Name is Harry Stitt, from Northern Ireland.


Harry Stitt BSA Frames.

Harry is only 20 years old, educated at the Belfast Royal Academy.

He is some sort of magician with a welding torch at this age, and has been building BSA frames for some time and has a reputation for the quality and design of the frames.

Not only that but he proves them himself by riding Classic Scrambles.

There is a page for Harry Stitt BSA Otter, check it out.

We now have someone capable of keeping the BSA Otter name going forward for the future...


Photo Courtesy Justyn Norek Snr.

This Harry Stitt BSA is the new Acquisition of Justyn Norek Junior.


Not only that but due to interest in every thing "Classic Trials Machines", we now cover not just only the BSA "Otter" and other BSA machines but other forgotten brands from both home and abroad, in fact from the World...



Here are three examples that are already within these Pages.


The Moto Guzzi...
Photo Courtesy Justyn Norek...


The Bianchi...

Photo Courtesy Justyn Norek...


The Parilla...

Photo Courtesy Justyn Norek...


Photo Courtesy Jack Knoops and "Offroad-Archives".


We will also cover some of the more interesting creations of steel and metal that eventually became the Star machines of not only the Magnificent British past but from the entire "Classic Trials Motorcycle" scene of the World...

The machine above is the ex Brian Martin BSA C15 being ridden in the 2012 Pre 65 Scottish.

by Andrew Paxton, for owner Edward Freeman...


Photo Courtesy "Otterman"©

We also have pages of "One Off" built Classic Trials bikes, all very interesting...

Above a home built "One off" BSA engined


Story on the Scorpion Page.


So Enjoy your journey through these many Interesting Pages...



 If you have any questions you may need answering about the BSA Otter Breed, or any other Classic Trials machines, or this website, Just Ask Me, by contacting me through the email address below, Or the Contact Page...


Pages will be updated weekly. And New Pages added all the time.

So call back won't you.


 We are here for You.

And to Help preserve the "Classic Trials bike Scene" that is our Heritage.

So enjoy our many pages, and there is interest not just for the "Classic Trials Rider."

But Tales about growing up in the trials country of North Oxfordshire, and Yorkshire, and Wales,

and even more to come.



So I hope you enjoy finding something interesting to you,

amongst these many Pages.

And If you have suggestions for more >contact me at


Regards Charlie.


Charlie Prescott aboard the Paul Beswick built Faber BSA B40 Otter...


Also Check out the Pages on the

Mini-Otter ® builds...


We still think this little bike is part of the future of Motorcycle trials, Both here and abroad...



Mini-Otter Number Two... showing it's size...



And the nice little Lifan 125cc engined Mini-Otter, Number  Four...



And the long suffering Mini-Otter Number One...

 The test-bed... 

More Later with the first Production build of the

Mini-Otter®-Super cub trials.......


For 2022 we also have a new series of trials bike tests by the Justyn's Norek that should be of interest, as these are very special trials bikes with loads of history...And with superb photography...



The ex "Works" Mick Andrews 320 YAMAHA MAJESTY...

Is one of the tests..Enjoy...

Stay Safe Folks...