OSSA

I need to replace the O rings on the fork caps of my 73 MAR with Betor forks. The measurements seem to be 3mm x 31mm. Here in the USA metric Orings are not locally common. Also, before I order them, I was hoping someone knew the proper size. Thanks

Well, I heard another rumor that OSSA may be back before next winter with 2018 bikes! of course, it is always 'we will see' but this one seems it could have a bit more truth than some. Anyone heard anything lately? Mark

I can bring my software/interface to the Kingman World Trial if anyone needs to give their OSSA a tune. I don't know my route back up north- so a possibility I could stop by if you live on my route. Mark

Does anyone have a tip on how to grease the linkage? Cant find any info on the net!?? Is it a wheel, swing take it all off operation? Heard that it should be done quite often. The patient is a 2012 tr280i. /D

I have just found out that where I thought I had a 250 MAR, it is in fact a 350. Last year I brought a new Minuki carb for the bike but spec'ed for a 250. What jets and setting should I change too?? i have noticed the bike has a low down flat spot , so hopefully this is the reason why?!

During a trial this weekend I noticed a creaking from the clutch mechanism whilst pulling in the lever. It is also heavier and notchier than my mates OSSA clutch. The noise seems to come from the cable, but I worry it might be transmitting up the cable from the clutch arm ?? Will a cable be the answer to my problems, and is there any way to make it lighter than it is ?

I'm new to this forum , just bought a 2012 Ossa tr280i , not really happy with the engine feel in bottom end and it keeps on flooding. So I'm trying to understand how the FI system works , I understand FI but I don't get how the Ossa does its calculations , my MAP sensor is In the outside air not the manifold , so is the amount of fuel dependent on the throttle position? (With some tweaks for engine temp etc) so the map sensor is only monitoring the barometric pressure ?

Hi does anyone know what bearings and bushes are needed for the swingarm thanks Lee

Hi guys. Got a 2012 Ossa TR280i for a price i could not say no to. I'm a bit worried about parts, and already want to order me a new rear fender as i am pretty sure I'm going to break the one on the bike eventually. Where can one order Ossa bits these days?

As above, has anyone tried to fit the new style flexi rear fender on the old style seat base? If so, is it a direct bolt on or was there a modification required?

I first will say I appreciate the experience and knowledge here. I grew up riding when these machines were being made, but never considered them as I was a kid growing up racing MX when the Japanese bikes arrived and became dominant. Fast forward to 2016, I wanted a trials bike. Many reasons why. My good friend and riding buddy purchased a 72 MAR about a year ago that was supposedly very nice. He learned it was good but lacking in the fine details and he does not have or own junk. A few weeks ago, knowing he needed some original parts, I noticed another MAR on a Facebook group that was for sale reasonably inexpensive. He acquired it. So he had plans to build a …

Hi just acquired a 2012 ossa tr280i but I have a couple of problems with it , firstly the linkage is showing signs of play ,looks like its coming from the centre bolt on the rocker , where can I buy new bushes and pins , also rear silencer is cracked badly so looks like I need to get that welded , but I'm guessing it will eventually fall apart again . also the rear wheel bearings are shot , does anybody know what size bearing they are ,? thanks in advance.

Bit of a stupid question, but when you put the nut securing wire on the mar clutch, do you route the wire through all 5 posts or wire them individually

Sorry for another daft question,but I've nearly finished the rebuild i wish i hadn't started. have just received a new countershaft sprocket which i ordered specifically for it, it has a shoulder on it.( talon TG375 ) The one i have just taken off hasn't so theres not a lot of threads left for the nut soo frustating, can anyone confirm the talon sprocket is correct, and do i need to get another sprocket spacer.

Stupid question time .... How on earth do you remove the ECU from a 2013 onwards TR280 ( the ecu is mounted down by the cylinder ) . Do I need to remove the radiator first or am I missing something plainly obvious? Would like to make sure the plug is dry and fill with electrical grease but it's not nearly as simple as it first appears

Hi All, Just starting a resto' of a 350 Explorer. Mostly complete,engine on the bench,just missing the long travel seat if anyone knows where I can get one? Does anyone know the proper frame colour on these. As you can see from photos it obviously been sprayed in the past but there are 2 colours,black and a dark silver. I have seen them in various shots/brochures with a black frame as well as silver as the MAR. So can anyone help,were they black or silver. Thanks in anticipation for your help and any advice

I have taken the time to search and read about these bikes. I recently acquired a 1973 MAR and was wondering if the center exhaust section contains or contained at one point packing material, or is it baffled, or simply a small expansion chamber? I ask on account of wanting to clean it off carbon deposits internally and externally prep it for paint.

iS there anywhere I can get a Cush-drive shaft puller in the uk I know Keith Lynas has them across the pond

Following the issues with my mar first having an oil leak, then jumping out of gear, I have removed the oil and refilled it a couple of times. The first time I drained the remainder of the oil that hadn't already leaked out, then filled it with 900cc / ml of oil. Following a 5 min ride I left it to drain again over night. After re fitting the detent plunger I went to put the drained oil back into the bike. To my surprise there was only 600 ml in the catch tank ?????!!!!!! Where are the other 300ml ??

As above, does anyone know of wider aftermarket pegs that bolt straight on ?