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feetupfun

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  1. feetupfun

    Rickman

    Larry I'm going to have a go at re-writing what I think you have written to see if I have understood your posting. "I can't find a Rickman forum. I've got Rickman Montesa and Rickman Hodaka project bikes. I bought the Rickman Hodaka frame from a wrecker in Michigan. Most small Rickmans are for Zundapp engines. The frame has a H stamp. I found parts to complete it on ebay. The 100cc motor runs and shifts. The forks and wheels are from super rat 125. Either the motor or the frame is 6/71 which was on a small tag on the left side. The whole project has cost $US1500 so far. The motor is either stock with some Super rat parts or I might try and use some super rat parts or I might look for a better performing Hodaka engine. The gearing on it is very high. The Montesa did run but a few hours after I bought it, I found it had a broken gearbox shaft which needed the cases split and parts to fix it. The motor is the same as what came in a 1973 250 Cappra VR. It was stored in a barn in East Washington State for 20 to 30 years, was ridden by two brothers then a son. It was delivered to me. I could not believe how high the compression or the power was for an old engine. I am sure it has a pickled cylinder. It has rust in the tank and wheels. It's been pulled apart and stored in boxes. I have bought parts to fix it from a dealer in Oregon for when I can get to it. I've rebuilt some Bultaco motors. These Rickmans are not for sale. I like seeing photos of Rickmans but there are not many photos on the trials forum. I lost my Rickman photos when my other PC died. There are pictures of me at "Happy Hodaka Day"."
  2. feetupfun

    Unleaded Fuel

    Not related to the liquid compatibility as such, but there is an issue with modern pump petrol forming a very strong and adherent gum when it dries out.
  3. If it's just the brake action you want to improve, why do you also need to swap the shifting over? Lots of people ride trials with shift and foot brake on the same side
  4. Montesa dirt bike. Similar to Cota 348/349 but your hub is bigger and stronger. Cota 348/349 is 118mm sprocket ID. I had a Montesa Cappra 125 rear hub that looked like that and it was bigger than the Cota 348 hub.
  5. To get a bit of movement started you could heat the outside of the fork tube at the position where the damper rod piston is stuck while gently tapping opposing ends of the damper rod in turn
  6. Front braking while turning downhill is helpful for balance and speed control. Front braking technique is important when you are going downhill and turning from across the hill to downhill because weight is becoming transferred to the front. Rear braking is important for controlling the bike in turns that require some engine power.
  7. feetupfun

    Crank centering

    Another thing that can help with this sort of work is to modify the ID or OD of the old main bearings enough so that after fitting the new conrod, you can do any test-fitting of the crankshaft with ease at room temperature
  8. feetupfun

    Crank centering

    DickyM it's the centreing of the conrod in the bore that is important rather than equalising the side clearances on the crankwheels. You may not need a shim to achieve this.
  9. Because there is more torque on the clutch in the higher gears
  10. feetupfun

    BETA USD FORKS

    You got me wondering if I was imagining USD forks on my friend's bike so I went looking for photos. Here are a couple of photos of my friend's 2001 Rev 3 270 showing the USD forks that it came with (the bike that you have been told none were brought into Australia). Photos taken in 2004 or 2005 when the Queensland Trials Titles were held near Dayboro. From memory the first owner was Kris Hammond. Second owner (shown in photo) was Ken Cutmore.
  11. feetupfun

    BETA USD FORKS

    A friend of mine had your model Rev 3 with USD forks and it developed more sag than normal and he discovered that the fork spring was broken. If yours is a 270 it might even be the same bike. My memory is telling me that those forks were standard on the first model Rev 3 and were optional on the second model Rev 3. Yours looks like the second model which I would call the 2001 model. This is what the first model Rev 3 looks like
  12. I don't think it will have an oil filter. If it's like the Jotagas bikes I've seen they are two strokes. Normally only 4 strokes have oil filters.
  13. Wow that's amazingly original after all the years. Good find and great to see. Thanks for the photo. The absence of external damage and wear makes me think it must have been parked up somewhere for almost its entire life so far. The tyres look like 1970s type. I bought a TY250 in this sort of condition in 1994 and was amazed at how unused and undamaged it was at the time but that was 26 years ago so yours is even more surprising.
  14. The A model fits yours and the BCDE covers are all the same. Either cover suits either flywheel on any engine. They changed the cover design to make the motor look slimmer after initial criticism of the width of the A model engine and also to help keep the bike at the same weight despite the heavier flywheel. The BCDE cover is magnesium while the A cover is aluminium. Other weight saving changes to keep the weight the same with the later, heavier flywheel were aluminium brake arms, magnesium clutch cover and oil pump cover and an aluminium fuel tank. If you do get an A model magneto cover, a BCDE model shift lever will probably not suit the shape of the A model cover.
  15. and another one https://www.ebay.com.au/itm/1974-YAMAHA-TY250-TY-250-Stator-Cover-Mag-Cover/362581712843?epid=1681129835&hash=item546b8ddfcb:g:2DoAAOSw~Tdch9zo
  16. and another one https://www.ebay.com.au/itm/1974-YAMAHA-TY250-TY-250-Stator-Cover-Mag-Cover/362581714795?epid=1681129835&hash=item546b8de76b:g:618AAOSwrERch93A
  17. Yes that's the A model cover. At times I've seen multiples of them advertised concurrently on eBay. Here's another one https://www.ebay.com.au/itm/74-YAMAHA-TY250-TY-250-A-OEM-LEFT-CASE-STATOR-COVER/202894542533?epid=1681129835&hash=item2f3d7506c5:g:Xx4AAOSw6PpeNMHi
  18. If you are unable to find that cover, the A model cover fits and they are in plentiful supply
  19. Those look like standard Cota 247 forks so they could be called Montesa or Betor-Montesa forks. I suspect were probably made under contract in the Betor factory in Spain for Montesa. They are slightly different internally to Bultaco Betors and OSSA Betors of the same era and the sliders are unique to the Cota 247. Ceriani brand forks were made in Italy but forks like those on your 247 are also known as Ceriani type forks because the internal design was originally developed by Ceriani and later copied by other fork manufacturers.
  20. Yes the brass piece. I bent it about 45 degrees which was enough. You know that even if you did break it, it could be replaced with a piece of brass or copper tubing. Those vent fittings are just glued into the body of the carby. Another consideration is that the carby has a bowl vent on each side so it probably makes no practical difference if one of them is blocked off
  21. I think I just bent the part the hose goes onto to give clearance. No money required
  22. Those drawings in parts books often contain things that are misleading. I've seen a drawing in a parts book for the internals of the forks of one bike (maybe a TY) and they have drawn the springs unrealistically which can cause confusion. Yes there is a performance advantage if you fit an ignition that changes the timing to suit the engine RPM compared with the standard TY ignition that has fixed spark timing. A fixed spark timing is only perfect at one particular RPM and choosing what timing you run it at is a compromise for the rest of the RPM range. In the case of your bike the advantages would include less tendency to kick back when starting and more power in the mid to high RPM range. My seat-of-the-pants estimate for the trials bikes I've fitted them to would be about an extra 10-20 % power available in the mid to high RPM ranges. There are probably modern aftermarket ignition systems that also have stator coils for lighting.
  23. The holes drilled in it are to balance it and were put there by the manufacturer. The steel ring/band on the outside of the "cup" of the flywheel does look to have been machined slightly narrower but it is hard to tell for sure with your photo. Trials two strokes generally have more flywheel effect built into the crankshaft than trail bikes and MX bikes. In the case of the TY250 motor the additional flywheel mass compared to the trailbike motor that the TY motor is based on is in the form of that steel ring fitted to the flywheel cup. The next and subsequent models of the TY250 twinshock have a bigger steel band there than the A model. Trials two strokes benefit from the additional flywheel effect because it smooths out the response of the motor at low RPM to changes in throttle input. This smoothness is important when riding trials sections to help with controlling the bike. The ideal amount of flywheel effect depends on the skill level and personal taste and riding style of the rider. The B and later model TY250 motors have a very strong flywheel effect which helped them perform well in the 1970s but since then the performance of tyres and the way we ride trials has changed so much that reducing the flywheel effect on those models is nowadays a popular modification. Back when the A model TY250 came out it was perceived as having a motor that was a bit too responsive which is why the steel band on the flywheel was made bigger. Nowadays the A model flywheel effect is seen as close to the ideal. When riding a TY250 on trails and roads, the additional flywheel effect of the TY compared with a similar motor in a trailbike with less flywheel effect is of no practical benefit.
  24. Depends on the design of the cap and what it screws onto. Some use a o ring. Some use a flat rubber seal.
  25. I'm the same weight as you and on my TY250 I've got standard damping Falcon trial classics with 50 lb springs and they are perfect for me. I don't hop the rear but if that is your intention then you would be better off with the superlight damping version.
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