Twinshock

Hi, does anyone know the differences between the two as i am after an o/s piston for a 247 montesa and as bultaco pistons are more common i was hoping they may be interchangeable without too much trouble, Are the small end bearings the same size (piston pin same size ) and the same height. I can always more the ring pins if needed Dave

Hi folks, Thought some of you might enjoy seeing my winters project. Not sure how many of these you see over your way, but not too many in these parts.

I've got an OSSA TR77 that i'm doing up at the moment and it's a 250. Got no carb on it but i have a Bing off a 350 TR77 so i was going to fit that. Just wondering if anybody knew the jet sizes for the 250 as i assume they are possibly smaller than the ones for the 350 ? also the carb is leaking petrol. Now i thought it was flooding but after stripping and turning upside down the float needle seems to be sealing ok when i blow through the fuel pipe and there doesnt seem to be any fuel in the float which would normally indicate a punctured float. The float needle valve doesnt seem to be worn either. So only other thing i can think of is the gasket for the float bowl. Are t…

My Cota 247 has had quite a few bar bending spills - and now even a light fall results in a bend so I I think they are past their use by date. Can I get some suggestions on replacements. I do like the original wide bars they are approx 820 mm (32 inches) and I would prefer something without the cross bar support so as to keep the original look.

Does anyone know if you can just buy the mid box separately (I already have the tail pipe) or anyone selling one second hand?

Im of to the murcia region of spain (west) on the 24th of Feb does anyone know of any trials bike museums in this area? thanks in advance!

The article speaks for itself. Maybe a little bit off on the facts but the spirit of the day was captured very nicely.

Does anyone know the origins of this swinging arm? I think its an aftermarket item as it weighs a lot less than a standard mk1 and mk2 mar swinging arm, is brazed instead of welded and is approx 60mm longer than a standard swinging arm Its currently on my '76 mar but cant find a photo of another bike with one

Does anyone know the email / phone contact for Steve Sell for Ossa MAR parts. Many Thanks Brian H NZ

Now the Cota from hell has a shiney new piston and barrell bored to suit, I need to spend even more money on brake shoes! Which are best and are there any brands I should avoid? As for gearing standard according to the manual is 11 - 54 or 10 - 49, is this OK? Anyway here are some pics

well what can I say hmmm thought I would leave the comments from you guys

My TLR 200 had a badly rusted tank when I inherited it 12 months ago. Initially I tried the molasses treatment - 10 days submerged improved it but it didn't really control it so I fitted inline filters and became used to cleaning the idle jet. I have since tried other rust converters but once you rinse them out it is rusting again before the rinse water dries. However riding with a mate on his very sweet Bultaco M125 a few weeks ago and he was going through the rigours of draining his tank after a ride because of ethanol concerns and this made me a bit concerned about what may be happening on my Cota 247. So I decided to try and resolve both issues and I found an Aus…

Hello.. A Mildrewism. I don't bloody belive it. A lot of Mr Schreibers old bikes popping up all over California thesedays What do you think...! http://www.ebay.com/itm/1972-OSSA-MAR-formerly-Schrieber-owned-AHRMA-Trials-TL-RL-TY-Mick-Andrews-SS-1-/280969804102?pt=Motorcycles_Parts_Accessories&hash=item416b1af946&vxp=mtr 1972 Ossa MAR Trials machine in need of resto. Non running. Formerly owned by world Trials Champion Bernie Schrieber. A good friend of mine Steve Elliott's Father bought 3 bikes from Bernie when he lived in LA Canada, California in the late 1970's and this is one of them. Note that all cables are …

Hi all , i am restoring a pair of yellow and orange Ossa gripper's 250 and 350. Does any one know the paint RAL code for the orange and yellow colours? Also does any one know of a good fibreglass making person who can make side panels etc , not just ossa but other bike/parts as well? Thanks

Ive spotted this Ossa on ebay. I know nothing about them so i was just wondering, is it as rare as he claims and if so, what is different to the others i have seen? Ebay Ossa

I need to remove the primary drive on my 1980 349 and found this thread, any other tips as it's sure on there tight! http://www.trialscentral.com/forums/index....y+drive+montesa seems freezer spray on the crank and heat on the gear is the way to go? Thanks Steve

Hi, my latest project is getting costly as i have just pressed apart the big end to find the rod is ovaled and knackered. Anyone know where i can get a kit from or at the least a serviceable rod? cheers Dave

I was going to replace thirty years old front fork springs. The length of the new ones (which were said to be for 348!) were only 47 cm but my original are 50 cm. What's the right length? So whatever it is, I desided to lathe some nylon spacers (30-40 mm) and try with them.

Think I posted having problems getting one of the gearbox bearings out, in a blind hole. The bearing is conical, and a small amount of leverage popped out the balls and carrier leaving a conical internal surface and no space behind to get anything substantial in to grip: So I ended up grinding it out (no damage to the case

A pair just sold for