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lemur

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Everything posted by lemur

  1. Working on excavators and farm tractors and operating them year round I noticed they are just huge heavy duty versions of a trials bike transmission. I run shorty levers so the clutch engagement changes just with that change, clutch progression is the result of hydraulics. I think ATF is perfect for automatic transmissions, my trials bikes all have one of the most simple standard transmissions and organic friction plate clutch systems ever produced. The ISO 46 works even in sub zero it is considered all-weather. Water swells clutch plates and lowers the burn point of the oil in the clutch. Burning the oil between the friction plates is what causes the carbon glaze that builds up on a cooked wet clutch and that comes from improper combined clutch & throttle control. The ISO or SAE or AGMA measure is the viscosity measure relative to temperature, the rest of what differs is what additives are in the oil to make them suit a particular task. If you had to do a 45 gallon oil change in an excavator or farm tractor at the cost of some small package oils being sold in bike shops, you would go broke real fast.
  2. Mr

    lemur replied to JohnAaron's topic in Montesa
    The parts diagram for the 247 Cota shows the assembly order a little better and the forks appear to be similar in construction to the 200.
  3. 5 Montesa 4RT bikes over 20 years I only used ISO 46 hydraulic transmission oil in the transmission/clutch casing, never had a lick of transmission or clutch problems and the oil cost 7$ per oil change, change it frequently because there is no filtration on the transmission, the thing that destroys the oil is water from condensation or pressure washers. ... don't use pressure washers or swamp the bike and your oil will last longer 👍
  4. omg Honda PGM-Fi is light years superior to the CV carb on any motorcycle, it has one screw to adjust, the idle and it never misses a beat. Beta CV carb has what? 2 chokes, vacuum fuel tap, vacuum throttle lag and a vented float bowl just like a toilet tank works. ... was it water or condensation in the connector to the throttle body? is fixed easy, open it and blow the water out.
  5. If the distribution and dealership representation was better here, I would be riding Montesa again. The Cota is far more settled in the suspension, not as lively as many 2T bikes and the 4RT thrive on revs with smooth throttle control and lots of clutch abuse, great bike for hill climbs and deep mud. They don't cold start in serious cold winter weather unless you have a heated garage or build a fire under it, small concern for most. After about 3 or 4 years you will need to learn how to adjust valve clearances very accurately.
  6. First 2 digits is the # of the week, last 2 digits are the year abbreviated, same with all tires.
  7. lemur replied to guy53's topic in Beta
    ... I mean the bike should have come with PGM-Fi instead of a being saddled with a CV carburetor, then it would be at least as good as a Montesa in performance and reliability.
  8. lemur replied to guy53's topic in Beta
    Nice bike but the carburetor rots.
  9. lemur replied to Andy-Walt's topic in Yamaha
    Did you test or replace the 5k resistor spark plug cap?
  10. You are comparing Bias ply tires to Radial ply tires, competition rear trials tires are all radials. At one time they did manufacture radial trials tires in both tube and tubeless type (Pirelli did) , not sure that is still the case. ... Historically tubeless tires were an extremely tight fit to bead on a rim that was not designed for tube tires. Not all rims have a safety bead.
  11. That's a yes, it's even the same part #.
  12. Would that be your enduro bike fitted with USD forks? ... things are made out of aluminum on competition trials bikes because aluminum weighs 1/3rd. that of steel which also has a tendency to rust. Same as with your enduro bike the axle provides the majority of support required to keep the fork legs running as one. Everything is beefier on your enduro bike to the tune of almost 80 additional pounds. How easy is it to twist and or break a modern trials bike? It's not easy at all, I've launched my bikes off cliffs and experienced relatively little damage, but I do tend to buy other then Gasgas bikes which are not exactly the sturdiest in the market but generally are the cheapest to buy. Example your foot peg brackets are welded to the tube steel frame and not replaceable bolt on components attached to an aluminum casting. Tube frame cracks around the headstock have been reported by owners and many friends that do own current models tell me the rear fenders are very expensive when they needed replacement. Beta has an even more fragile front fender brace made out of plastic. Front fork stanchion tubes (also aluminum) are the most expensive part that can be easy damaged by just a small scratch, but you can buy sacrificial fork guards to help protect those.
  13. That's what I meant by loosen everything.
  14. Loosen everything and bring it back into alignment then torque everything back down, odds are there is less damage then you think. Bracket is important in that, you only have a spring in one fork leg, so the only thing keeping the spring side and dampening side lower fork legs moving in unison is the strength of the axle and that fender brace. Align and tighten the fender brace last.
  15. Air rises where I live, so first I push the brake pads all the way open forcing most of the fluid back up into the reservoir where I drain it off with a large syringe, then I push fresh DOT4 UP through the brake calliper bleed screw and into the reservoir, then I pump up the brakes to bring there pads back in contact with the disc and fill the reservoir to the prescribed level. Your old fluid will be discoloured compared to the fresh fluid. Same syringe process works for bleeding a hydraulic clutch.
  16. ... water content in old brake fluid will boil when the brake becomes hot with use creating the worlds tinniest steam engine inside your hydraulics, it will work right up until the brakes gets hot enough to boil the water creating air bubbles in your brake system which is bad.
  17. That's easy; it doesn't take oil it uses brake fluid which absorbs water out of the atmosphere turning your brake fluid into something very toxic nasty. You need to do what is called a flush of the old brake fluid and replace it with fresh fluid without introducing any air into the hydraulic system. After that you will know if you require new rubber parts in the brake master cylinder or not.
  18. Engine was a CZ attempt but soon will be professionally converted to a TY175 engine 😎
  19. How much did that ride cost? If the dealer doesn't have a replacement float needle and seat which might not even be the problem, I think I would be inquiring about a replacement complete carburetor. It's only the most common carburetor on any current modern 2-stroke trials motorcycle.
  20. It's also there for the benefit of your minders fingers. Competition rules may even require the safety guards be in place if you are competing in a sanctioned event. see: FIM Trial Technical Rule 41.04 ... if you are riding in winter they become a problem with ice buildup and I remove the guard seasonally, but studded tires are crazy dangerous so only crazy people would ride or catch studded tire bikes in winter.
  21. Tried one of the slab back protectors and don't like it, replaced it with a Troy Lee Designs back and chest vest which is way better 👍 Thinking about purchasing a second Troy Lee vest in a different model to wear over the first one so they cover any missing areas. Nothing is cheap to buy any more. ... model is a UPV something
  22. Ignition timing is usually slightly advance to TDC typically 10 to 20 degrees before and the black box is what alters the spark advance more if the engine even has that feature, it might not. I found a parts manual online for that bike no problem no luck with a service manual. Faulty bottom end seals destroy the engines intake vacuum more then anything else (symptoms would be poor compression test, hard starting and not a crisp pop pop pop sound on the engine). Your CDI trigger coil should show some resistance, more resistance than the primary ignition coils typically have. The clearance distance between the stator coils and the flywheel magnets should be as small as possible for the best spark intensity. One of those coils is likely for ignition and the other is for lights or horn. Only way I know of to test the black box 100% is to have a second working bike and swap parts to troubleshoot.
  23. I think you are stuck with raising the peg profile or lowering the lever profile aka bending it. The levers do bend before braking, I have a badly bent one on one of my TRS now.
  24. lemur replied to sparkle21's topic in Montesa
    🤔 By repackaging something simple and selling it like something special ? Yep, shop at your local farm supply where people buy oil by the pail and get the same stuff or better at a fraction of the cost, then you can retire the rich guy that lives in his own trials area 👍
  25. lemur replied to sparkle21's topic in Montesa
    Found 08C35-HTX-740 in stock and available from Acura dealers 👍 it's only $144.60 CDN 🤣 that's a lot for happy.

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