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  1. Started by herman,

    A friend has imported one of these and there's a chance I might be able to pick it up from him. My riding buddy says the red 303 is a late effort hodge podge of parts and that the transmission is a time bomb. I know very little about these bikes. Is the bike a museum piece? If the tranny is fragile, are there options?

      • Like
    • 4 replies
    • 3.8k views
  2. Started by rocker1,

    Good evening I need to send my Ossa MAR engine complete with head and barrel from Spain to the UK. I have no way of weighing it can anyone tell me what it weighs? also any hints on a good and cheap carrier would be appreciated.

      • Like
    • 4 replies
    • 2.1k views
  3. Started by solway19,

    Hi All, I thought I would share this with you all. I have been looking at various options to repair the stripped threads on my barrel and came across Seager Engineering who were advertising the service for Norton's. They have carried out the repair by machining and installing a bronze insert with a parallel thread. The workmanship is superb and I would highly recommend them. Spoiler

      • Like
    • 3 replies
    • 2.6k views
  4. I use F type atf in the gear box, but every year my clutch gets very stuck. Any ideas for getting it unstuck right now and keeping it from sticking each winter would be greatly appreciated. Thanks

  5. Started by oaktrials,

    I recently added a trail tech in coolant temperature sensor to my 2014 Ossa TRi 250, I am seeing coolant temperatures of 220 to 230 degrees F during extended climbs of 1000 to 2000 feet at 5000 ft elevation. Can any Ossa owners confirm the coolant temperatures they see during high load operation. New cooling fan, radiator clean, fan relay good, fan turns on at about 160 and off at 155. No lifting of radiator cap relief, idle speed drops about 200 rpm at elevated temperature. See coolant temperatures of about 150 to 170 during normal trials riding activity.

      • Like
    • 28 replies
    • 6.9k views
  6. Started by gogs56,

    I have Pirelli MT43 tyres to fit on my OSSA MAR mk3. What tyre pressures should I use for road use?

    • 2 replies
    • 1.9k views
  7. Started by bondy,

    Hello can any 1 tell me the silencer on the TR77 250 dose it need the packing? I cant get into it dose it need to be cut open? I just want to make sure because its not my bike as am doing some work on it cheers.

    • 0 replies
    • 1.4k views
  8. Started by minienduro,

    Any one know where I can pick up a replacement ECU for a 2012 OSSA Explorer.

    • 1 reply
    • 1.7k views
  9. I ran across an old OSSA here in the USA and I need help identifying exactly what it is...I just can't figure it out. The owner says it's been sitting in storage for 30 years and was told the bike is all original. The handle bars mount to the top fork yoke with U-bolts. The Frame number is B251002 and the engine number is M250154. I'm leaning towards it being a 1967 Pioneer based on the engine number and the large front hub, the rest of the bike looks like a Pluma/Plonker. Any help is appreciated. I'll try to post pictures...I don't have any right now.

    • 4 replies
    • 2.5k views
  10. Started by tsiklonaut,

    My 2013 TR280i has started to smoke recently, any idea what might be the cause? Doesn't run so well as well and it doesn't seem to be the fuel mixture issue, I've tried with a different fresh fuel/oil mixture and still the same. I figure it's maybe a gearbox oil leaking slowly into crankcase room, but where that leak might occur, a bad crakshaft seal in one side? Any ideas?

      • Thanks
      • Like
    • 40 replies
    • 12.1k views
  11. Started by ossamar,

    Has anyone fitted a tank breather to an OSSA TR80 cap? Thoughts and details appreciated.

    • 1 reply
    • 1.5k views
  12. Started by rick_watts,

    Hi guys, I have owned a TR 77 for ages, just looked at the engine number and its M-640810 and there is no number on the frame. on all the reference tables the engine numbers start with a "B" can anyone help to confirm my engines identity ? many thanks Rick

    • 9 replies
    • 3.2k views
  13. Started by Gobig,

    Hello everyone, I'm Matteo from Italy, I have a Ossa tr 280 of 2012, the bike is fine but I have a couple of problems to solve unfortunately in Italy there is nothing and there are no active forums, I need help I would need the kscan program and the explanation on how to build the connection cable in Italy it costs around 550 $ and the program is not found. can someone help me? I should also connect the front LED headlight but I do not have the switch on the handlebars, what are the cables to connect? I will put a hidden switch I apologize if my english is not perfect thanks a lot to everyone

    • 24 replies
    • 6.9k views
  14. Started by deputy dawg,

    Hi all i have a 250 mar that I've restored, i had the engine rebuilt, new carb it fires up easily but it smokes quite badly, running 50.1 fuel, anyone any ideas as where to start?

      • Like
      • Thanks
    • 17 replies
    • 4.5k views
  15. Started by pindie,

    My kick start works fine going down but struggles to return. It’s like the case seal has swollen up and is tight on the shaft? Any ideas what I should order in advance before removing the clutch case and investigating deeper?

    • 11 replies
    • 5.2k views
  16. Started by scot taco,

    Is there anything inherently bad with the 350 engine compared to a 250? I thought that I remembered reading that they were prone to running hot and if so is it a real problem?

      • Like
    • 2 replies
    • 2.9k views
  17. Started by papapitufo,

    Hello everyone. I have the kscan software, but not the diagnostic cable. Does anyone know which cables go to every color in the control unit ? Has anyone made a cable as btwice? Thanks in advance.

      • Like
    • 25 replies
    • 9.1k views
  18. Started by konrad,

    If this topic has been discussed elsewhere, I could not find it. I'm curious how many bikes (and of what type) were actually produced. If the numbers are unknown, maybe we can estimate them from VINs? I think my 2011 280 was a very early arrival in the US. Its VIN ends in 165. Same with my 2014 250, its VIN ends in 35.

      • Like
    • 6 replies
    • 3.7k views
  19. Started by pindie,

    Changing my fork oil soon for new 5wt as per Birketts info. 160mm air gap. Is this measured with the springs in or out? My plan was strip, clean and re bush/seal the forks. Screw the bottom bolts in to seal and then fill and work the cartridge to purge air. Before the springs go in I’ll measure and set air gap to 160mm- does this sound about right?

    • 5 replies
    • 2.8k views
  20. Started by konrad,

    Several members have ask me for help with Mapping/Upgrading issues. I'd be a lot more willing to experiment if I had an "expendable" ECU laying around. It does not necessarily have to be fully functional. I realize this is a long shot, with the small number of bikes built, but I'll put whatever I learn into the public domain.

    • 2 replies
    • 2k views

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