The Ossa plonker.

244cc trials.





The Ossa factory were slipping behind the other two Spanish factories that were turning out trials bike to the new found market brought on by Bultaco when they cooperated with Sammy Miller to build them a winning machine, which he surly did.

 Montesa were also developing a observed trials  machine to jump onto this new found band wagon.

Ossa needed someone that had a name in this game to establish a link to what was hoped would be a profitable outcome.

 Searching the Star names that were available for someone who had knowledge of what was needed to build a competitive two stroke engined trials machine

 Well at that time  young Mick Andrews had been riding a AMC company re-badged Francis Barnett, now named a James, and rumour had it that the plug was about to be pulled on this works team, has they were getting out of competition to save money.

Mick had the call from the Ossa factory, and went over to visit them.

 What he needed to do was along the same lines as Sam did for Bultaco, and put a trials bike together with what was available. And then ride the machine to develop it.

 All that was really available that Mick thought could be made into a trials bike with a bit ,or perhaps a lot of work, was the companies so called trail-bike/scrambler that they were exporting to the USA and Canada. This little machine with its 231cc engine was the Ossa Pioneer.

So in the year 1967, Mick set about the job in hand. and aimed to build a bike capable of riding, and getting a result in the Scottish Six days trial,

 the way to develop the machine was to ride it in as many National trials here in the UK has he could.

The engine power was down so the capacity was upped with what was available, and this brought the "Plonker" machine as Mick named it out to 244cc.


(A trials bike was known as a "Plonker" here in the UK when most of the British machines had large four-stroke engines and with the advance lever pushed over to retard them old bikes would "Plonk".)


So now with the help as usual  with the great photo shots that

Justyn Norek Snr, always sends me, and the way his son young Justyn test rides any machine, with the front wheel pawwing for air,we will look at the photos of the "Ossa Plonker"

 And also thank the owner of the bike, for letting the Justyn's near it,to ride and photograph. we wait for the report on the ride later.


All photos Courtesy Justyn Norek Snr.



All photos Courtesy Justyn Norek Snr.


Note the "Bryan Wade" helmet design, Justyn is using.


All photos Courtesy Justyn Norek Snr.


That's more like our Justyn.


All photos Courtesy Justyn Norek Snr.


You can see why Mick eventually got the hacksaw out big-time to create the eventual MAR. the motor was as low as a BSA.


All photos Courtesy Justyn Norek Snr.


The machine just looks heavy, but was it?

or was it the glass-fibre clothing that made it look so.


All photos Courtesy Justyn Norek Snr.

The tree could tell a tale or two.



All photos Courtesy Justyn Norek Snr.

Magnificent shot Justyn


The engineering was just to heavy for a well developed trials machine but when you have a short space of time to get a bike together like Mick did.

 You use what you have for a start point and then modify the machine in your head first. 

ride it knowing that eventually you will have to start with a clean sheet of paper.



All photos Courtesy Justyn Norek Snr.


Not even an air box for Ossa but Bultaco were already using this method of engine breathing.

 Why ?

Well Ossa needed to get a trials bike out into the market-place quickly,so the "Plonker" was still basically a trailbike-scrambler, off of the asembly line, with as little modifications as they could get away with.

front wheel and a smaller hub was the biggest change and a small increase in cubic capacity.



Just a heavy old lump.



The only rear wheel able at the time so that had to be used, the front and the forks were at least lighter.


 But with the development we then got the  M,A,R later.



Even Justyn has to hang back to get that wheel into the air.


As always more Later.