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mcman56

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Everything posted by mcman56
 
 
  1. Forma Boulder have pretty good calf room. With calves on the large size and the big Leatt knee guards, Forma boots close but just barely. https://www.motosport.com/product/?code=SS-M-G-P-NA-PLA-DIRT&key=Leatt-2022-Dual-Axis-Knee-Guards&cc=us&variant[LBRI08C]=LBRI08C-X003-Y003&cc=us&variant[LBRI08C]=LBRI08C-X003-Y003&utm_source=google&utm_medium=pla&&mrkgadid=3327779862&mrkgcl=500&rkg_id=0&adpos=&creative=331604523753&device=c&matchtype=&network=g&product_id=LBRI08C-X003-Y003&gad_source=1&gclid=CjwKCAjwh4-wBhB3EiwAeJsppKMXOCXmGLvAbXSsWUN2Jn1gP9nM-DN0I6IWqL8Pqgp-QutvS5nC7BoCOWUQAvD_BwE&gclsrc=aw.ds
  2. This claims 155 lbs dry. IIRC, the beta 4t is about 7 1/2 pounds heavier than the 2t models. The Honda is then another 7 1/2 pounds heavier than the Beta 4t. https://www.outdoordepot.biz/Motorcycles-Beta-EVO-300-4-Stroke-2024-South-Fork-CO-cfe3b8b3-3612-42bc-b1b1-b081007ec67e This says 170 lbs wet for the Honda. https://www.dirtrider.com/dirt-bikes/montesa-honda-trials-motorcycles-2023/
  3. I stand corrected. The number is 60 hours and came from an ISDT preparation manual put out by Lampkins. I was just following that recommendation but the clearance never seems to change. There was no failure.
  4. I have a 16 Beta 300 4t and have been checking valves every 50 hours but they never seem to change so plan to stop. It is a lot of work to get to the valves. Everything comes off the motor except the swing arm bolt and the engine then rotates down around the bolt to get valve access. It is also quite a bit more work to get to the carb compared to the 2t. It is the quietest bike and easy to kick.
  5. Not the same bike but I once had an early 90s Fantic 80 for one of my kids. It had full size wheels and was a full size bike or almost full size. It probably weighed as much as a current trials bike or a bit more. Power was adequate for a 155 lb person to pop over moderate size logs. It worked pretty well on the flat but any kind of a hill was an issue. Even a very moderate size hill required max rpm in first gear just to get up. Modern 80s probably have more power but when you test ride be sure to try some kind of hill.
  6. This is what the RT cover looks like, There is not quite enough room for the kick starter on the shaft.
  7. mcman56

    TY175 Clutch

    Once again, the clutch started to drag and hot stick. I then replaced the steel plates with new Yamaha plates, it worked well for a short while but started doing it again. These plates do have the dimples. I just sanded the steel plates with 180 grit and it seems OK for now. Could it be that you need to replace the friction and steel plates at the same time? This seems strange. I also get cold stick but don't care about that.
  8. The rear brake is the one thing I dislike about Evos. The Beta 4t has the brake on the other side yet has the same weakness. In addition, I found Rev3 rear brakes to work fine. I sometimes wonder if the lack of feel on Evo rear brakes is actually the brake lever (flex?). Or maybe it is the combination of the lever and my small feet (size 9). The picture is more vulnerable but a workable solution. I think the Jitsie lever helps a little also. Early Rev3s had a 2 piston caliper in the back. I did this after replacing all brake components including the disc and trying all available pads.
  9. Where do you find the flash point? Is there a comparison chart somewhere?
  10. That is a very interesting way to try laid down shocks. How much did it raise the seat height? It reminds me a bit of this.
  11. The angle of rotation (back/ up) is usually different for modern trials pegs vs vintage trials pegs and all MX bikes. If you find modern pegs to bolt on they may not be horizontal on top. In addition, you need to consider kick start clearance. I widened the stock pegs. The funny angle is for kick start clearance.
  12. Earlier Beta 4ts had a slightly quicker throttle, at least in the initial stage. I think the change happened around 2019. I have a 2016 and when I went to the later throttle is made operation with small throttle openings easier to control. I'm not sure if you can still get the old model from Beta. However, when looking for a replacement tube for my 2016 throttle, I found that the one used on KTM 50 4t was exactly the same. This may be it but the description is odd. https://dominoracing.com/shop/off-road/domino-4t-throttle-system/ https://dominoracing.com/shop/off-road/4t-spare-parts/
  13. Attached is a scan from an old Hotrods catalog. It shows all rod/ pin dimensions for a number of YZ250 engines. I would be curious to hear if one matches your engine. The catalog also shows pins available by size but it is from 2007. I see that Hotrods is now part of the Allballs group and still sells individual pins. https://www.allballsracinggroup.com/p126-crank-pin Scanned Document.pdf
  14. That should come with the rod kit.
  15. I ended up going to the Tubliss system and the issue appears to be gone. I expected mounting to be quite difficult but it was not bad. I see their claim about it being lighter. I did not weigh anything but I would say... maybe and it probably depends on the thickness of the 4:00 x 18 tube you are running. The 18" tube and two rim locks go away. You add a skinny bicycle type tube, plastic cover and lightweight rim lock/ pressure valve. Provided plastic tape replaces the rim band.
  16. "bounced me backwards just a bit pulling on the throttle." That is exactly what I would describe as the throttle getting away from you. In that situation, a smaller front sprocket makes the bike run out of RPMs quicker so it can sort of choke off or minimize the "getting away from you". It is cheap and easy to try.
  17. A couple of years ago, I bought an 01 Rev3 270 with almost zero wear on the original tires. Power was very sharp right off the bottom with the initial crack of the throttle. It was much much sharper than my 2014 Evo 300 2t Factory off the bottom. (The 300 Factory sort of took off mid range.) I added a full millimeter of base gasket for a total of 1.5 mm. Then I installed the heaviest flywheel weight I could find. It was something from a Techno marked Ducati. Power delivery is much smoother and it is easier to kick. I would think anyone who likes vintage bikes like a TY250 would like flywheel weights on modern bikes. I also find that going down a tooth on the front sprocket helps. The clutch out speed is slower so it makes clutch use easier in slow tight turns. (I'm no clutch master.) But, based on your injury description, you may have been going pretty fast. A smaller front sprocket also reduces the tendency to build speed with a series of obstacles to clear like log-log-log. If the throttle does get away from you, the bike will also run out of RPMs quicker with a smaller front sprocket so you can't get in as much trouble. I have tried 2 teeth lower but find it reduces the ability to get up and over things in first gear. A smaller front sprocket does reduce top speed if that is important.
  18. This issue continues. I was deflating and reinflating tube to get it centered every couple of rides. I also increased pressure to 5 psi. In other bikes I use 4 psi. I stopped the deflation/ inflation step and developed a leak at the valve stem in a maybe 5 short rides. I installed a 4:25/ 4:50 tube and ripped the stem off in only a few miles of dirt with no rocks. There was no impact. I just came around a turn on a flat road, gave it a good bit of throttle and could feel it go flat all at once. The tire remained seated on the rim. I rode the bike about 1/4 mile with the flat and the tire was still firmly seated on the rim. The bike has a DID 2.15 x 18 rim. This is really odd. I'm not sure if I should try an IRC tire or maybe the tubliss system. Does anyone run Tubliss on a trials bike?
  19. I run an FMF universal muffler on a TY175 and it really quieted the bike down. On that bike, I was able to just cut off the OEM muffler and clamp the new muffler on. I used the smaller FMF universal but did need a reducing collar to fit the TY. I can't picture how thick a the TY mono muffler is but the FMF is a bit wider than modern trials mufflers so you have to make sure you have clearance. Beta 4t (at least some years) had no external stinger to clamp on so the spainsh fly spark arrestor came with a short piece of tubing you had to weld on the back of the muffler to accept the spark arrestor.
  20. A friend runs a Fisch on the standard muffler. It has the official markings. https://fischmoto.com/products/fisch-moto-spark-arrestor There are also these. https://spanishflyracing.com/collections/usfs-approved-trials-spark-arrestors?page=1 These types come in different sizes. They have the correct screen size but I don't think they have the official words. They do pass inspection at the CA off road parks I go to. https://www.ebay.com/itm/144812387857?epid=2036443760&hash=item21b77dae11:g:mG4AAOSwxuRdAQGy&amdata=enc%3AAQAIAAAA8Bo2BHlkCXTg7Kn4Te3UWlLpEySMWS40xxfzj%2FIPPL2TFnH2VPCNU46qnjf7EB5GOrl1o4kc2alPDjZ%2FnilZCPKIR%2FNud4bYtPC3hYB%2BSb2kcQW4LXx2eFxF8KcFBnBjOA2oYscMNuivkbPhg639mMsZ5AQWd%2BlqY4MlQ%2BfgkpdMETL1LWf8NwzsD6PICnbPnezD7hqwVOqbFOj%2F%2FMaEtgurY69G833xzp4VqzFCCQIyPXUq6954mLEZyZVpvpMd%2FDHDC3eBb%2FTSBdr%2BrhFxUidY9PXW2KfKrwiEtVFmOKFNfL6qoRLblcY%2BQlbKuSAA%2Bg%3D%3D|tkp%3ABk9SR-jQoIXVYg Another https://www.speedandsport.com/product/spark-arrestor-screen-universal/
  21. The O5 in a circle sounds like a casting date. Things like this would be cast in large lot sizes. Then there is machining and painting plus transit times. I have spent a little time looking at casting dates on Beta cylinders. A cylinder with 05 casting date would likely be found on a 2006 or even a 2007.
  22. I was able to reduce shock through the handlebars on my TY175 by using a fat bar and rubber mounts from a mid 2000 CRF250. See picture. I was already using risers to put the bars in that position so there was no ergonomic change. At rest, I can flex the bars a bit but notice no negatives while riding. Rox Risers sell something that looks similar. I don't see a good way to squeeze these into a modern bike without a big change in bar position but have found it is quite easy to change the valving in a modern Beta's forks. https://ibb.co/GWLwwMB
  23. Can someone clarify how to install the front sprocket retention hardware for a TL250?. There is a flat washer with cut outs to slide on the spline. There is a second washer with similar cutouts which also has some horizontal protrusions that will mate with the first washer. However, I don't see how these two washers can mate once on the spline. Then there is an e ring that fits but is not a tight fit in the groove on the spline.
 
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