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Tillerman6

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Everything posted by Tillerman6

  1. Junglejeff, thanks for the reply. One major problem with piston replacements is weight change. The yz piston is 30 grams heavier than the TY so unless you do some major magic, it’s gonna vibrate like hell. I’m about half affraid to open the box from B&J as he has it apart and says he cant’ figure out what to do If I can make the special tools to put the cases back together I will try that. If not, it’s going to get sold for parts. Nobody is gonna hold my engine for ransom any more
  2. Duly noted and I ended up spraying it myself with automotive paint. Glad I didn't powder coat after all! Thinking of following that with a clear coat before re- assembly if I ever get the engine back and back together. Arrrrgggghhh!
  3. Tony- Thanks for that input, but I found that just by warming up the rubber coupling with a hair dryer it comes back to life and you can still use it. - Don't get it too hot, but even warm water should be enough to soften the material and it becomes stretchy and not prone to crack again. Good luck!
  4. I went ahead and used the automotive paint on most of the frame. Should have sanded it more. A little rough to the touch now. But that's the least of my problems with this bike. The engine has been in limbo at B&J racing since April, so I'm having him send it back to me AS IS. I don't think I will worry about the paint if the engine is toast.
  5. Well it's been April 21 to July 11. My lower engine cases were sent to B&J racing in Tennessee for a look see. After all that time- no joy. The owner said he didn't have time to put the crank in his lathe and check it out completely and he doesn't know where the metal chips he found inside came from. Apparently it was not a good time to send my engine to him. He had some serious family child illness and several trials events occurred during that time, so I guess I can't be too unhappy about the delay, but not having any idea about when my engine would be fixed was too much for me. They are super busy. So I am having him send me back the engine as is. They also did not find any pin from the needle bearing inside, so at least it was not in there doing nasty things to the innards. I am going to withhold judgement on B& J until I see what's been done and what I can do to fix it myself. If there is not too much damage, I will be trying to fabricate or borrow the tooling needed to re-assemble the engine case halves. If anyone has done this operation with the factory tools or equivalent, I would very much like to hear about the process and the tools needed.
  6. Sorry it took me so long to get back to the question of seal replacement- You guys are great for making these comments! I feel a lot better after reading that I am not the only one having difficulty putting in the All Balls Racing seals. - I am lucky to have some precision tools to scope things out. So after getting one seal stuck half way in and half way out, I decided to measure everything and see what was actually going on with the fit between the seals and the slider inside diameter.- As Feeetup fun said, the new seals from AllBalls racing have a moulded ridge near the bottom which protrudes out around the circumference .This protrusion seems to be mostly "flashing" from the plastic moulding process, and I managed to trim most of it off with sandpaper at first. I wanted to get a micrometer reading on the OD. Much to my surprise it was .008" oversize for the bore of the sliders! And the sliders were not out of round, but the seals are not concentric. So after much dissapointment and considering my options, I decided to grind down the plastic seal OD to a point where it would go into the slider tube without destroying itself or the slider tube. I have a Dremel hand piece with a flex shaft and I put a standard coarse sandpaper drum on the handpiece and then put the handpiece in the tool holder for my Southbend Lathe. This gave me a steady and controllable way to reduce the diameter of the seal( oh I forgot to mention I made a 34mm mandrel on the lathe and mounted the seals on it while grinding down the OD of the seals. I was pretty surprised to find that the seals were several thousandths out of concenticity as well as being oversized. So as the grinding progressed - very quickly I was down to just .0015" oversize and I decided to stop there. Good thing I did becase any more and the seals would have probably been too loose of a fit to withstand the oil and air pressure changes that they will see in use.
  7. Well, more seal problems- the All Balls seals jammed half way into the seats on the fork tubes and had to be removed. I made a male plug the same size as the fork slider and plugged up the bottom end with a threaded thick aluminum washer. this lead out to another washer on the outside bottom end and another nut. this sealed up the bottom end and I poured the fork leg full of water. Then with the fork tube in special jaws on the vise I put the male plug thru the seal and it rested on the water inside the tube. the seal kept the water inside when I hit the top of the special plug with a hammer. After a few whacks with a 5 pound mallet, the seal was pushed out from the inside by the hydraulic pressure. There was still some damage to the outside of the seal, but the fork tube did not get any scratches from a wrench or screwdriver this way. Now I am wondering if I can grind down the seals to a more reasonable diameter. The fork sliders are 45.999mm on the ID or 1.810" but the seals are .012" oversize or 1.822". Any ideas? I know they are supposed to be tight, but the seals are not just rubber. Has any of you guys ever run into this problem before?
  8. Well, more seal problems- the All Balls seals jammed half way into the seats on the fork tubes and had to be removed. I made a male plug the same size as the fork tube and plugged up the bottom end with a threaded thick aluminum washer. this lead out to another washer on the outside bottom end and another nut. this sealed up the bottom end and I poured the fork leg full of water. Then with the fork tube in special jaws on the vise I put the male plug thru the seal and it rested on the water inside the tube. the seal kept the water inside when I hit the top of the plug with a hammer. After a few whacks with a 5 pound mallet, the seal was pushed out from the inside by the hydraulic pressure. There was still some damage to the outside of the seal, but the fork tube did not get any scratches from a wrench or screwdriver this way. Now I am wondering if I can grind down the seals to a more reasonable diameter. The fork tubes are 45.999mm on the ID or 1.810" but the seals are .012" oversize or 1.822". Any ideas? I know they are supposed to be tight, but the seals are not just rubber. Has any of you guys ever run into this problem before?
  9. Kind of a generic problem I think. the fork sliders are from a 75 DT 250 and the seals are aftermarket from "All Balls Racing". The online instructions say to use a fork seal driver. Or if you don't have one of those, use a piece of PVC pipe split in half and put back together with a hose clamp. It looks like the fork tube is also inserted into the slider at the time that the fork seals are driven home. Well, I did it another way with a male plug with a shoulder at the top just slightly smaller than the seal OD on the top end and just slightly smaller than the inner bushing on the inside of the slider.- Then hammered on the bushing I made which should have driven the seal in straight. It was well lubed and so was the fork tube, but the seal refuses to seat all the way. I'm hitting the driver I made pretty hard, but the seal is stuck about flush with the top edge of the slider. Any ideas? Are all seals this tight?
  10. Had a frustrating morning this morning as the seals I bought on Amazon did not fit the fork tubes. The fitment list said they would work, but did not. And they want about 40.00 US for each seal if you buy OEM seals from Yamaha 584-23145-50-00 for the 75 DT250. So I am trying a set from All Balls. For 30 bucks you get 2 seals and 2 dust covers. Hope they fit. I almost wrecked one of my fork sliders trying to get the first ones installed. It had a steel outer ring and it was .006" too big for the fork slider GRRRRRRRRRRRRRRRR! So it's going back. Live and learn. The next ones do not have the steel ring on the OD, so if they don't fit at least it will not damage the inside of the tube.
  11. Feetupfun, I think actually I like the MX/YZ backing plates better since I'm not running a speedo. They sure made a lot of different versions over the years! Those shoes of yours marked 401 are from a MX 125 originally and you could look for more shoes on Ebay or whatever from that bike and that's how I got my new shoes that are on my bike now. They were brand new and not all that expensive on Ebay. They were not 401 series but something close. I checked out the Racetech Gold fork valves and looks like they don't make a version that will fit the 75 DT 250 B/C forks. I think the do make something for the MX/YZ forks in some years. So are you machining down the new shoes to fit the drum housings better, or you have found a source of brake shoe material and scrape off the old ones and somehow attach the new ones yourself? If I get rich I could email Race Tech and see if they could send me a set of valves that had not been sized for another application. Possibly I could thread them and adapt them to my forks? Do they go inside the forks or sit on top?
  12. While we are on the subject of tracing parts back to their parent machines, I remembered that I had a "Yamaha Cross reference Index file on my computer. I can't seem to get it to copy and send to the Trials Central website, but I'm working on that. I think everyone that has an old Yamaha should have that information available. It's really just a list of the first 3 digits of the Yamaha part numbers and a "Tag" name for each one. The first 3 digits are code for the original bike that the parts were built for. Other bikes use the same parts later on, but having the 3 digit code on a part tells you what other bike the parts were originally used on. That way you can look up that year and model on Ebay or whatever under the original year and model and possibly find your missing parts that way. For instance, the part numbers beginning with 434 were TY parts. My brake shoes off the front wheel were 322 which was from an RT2 MR ( maybe a street bike?) I used Windows Photo Viewer to open these. Hope this helps! I will keep trying.
  13. Rim pic below. I's a DID rim. So are the "speedo drive lugs" right near the axle on the side away from the brake drum? 3 little tabs that stick out just a little? Did a little painting of the frame today. It's supposed to rain for 3 days starting tomorrow, so I had to get that going. Handlebar risers just need longer bolts to finish up.
  14. Well the UPS truck brought the new front tire today and I put it on the rim today. (pics below) The rim itself is a 21 x 1.6 after all. Apparently they measure between the rim edges on the inside and not the outside. The brake drum diameter is 130mm if that helps any. The shoes are marked "322-00". I was surprised at the weight of the new trials Dunlop D803GP at around 7 pounds whereas the knobby I took off was only about 6 pounds! Anyway, the width of the rim is probably the same as a TY rim at 1.6", so the weight of the wheel should fall in close to the TY wheel overall. The brake backing plate is magnesium, so that will not be a factor. I think the OD of the shoes will be very close to the 130mm ID of the brake hub if that helps any..
  15. Feetupfun, Glad to get your help! I think the DT250 B/C is exactly what I have. You would not think that KYB would make so many different forks for bikes that are more or less the same thing. Tell me about the Race Tech Valves. I'll send you a pic of my brake drum, but I'm guessing it is also DT250 B/C since the forks are. No problem with having enough weight I'm 180 lbs. Shocks will go on with body on top. (no mystery now) Will stick with the DT forks for now unless there is a windfall of TY parts coming my way. They sell sleeves for the fork sliders ready made. They would need a special jig made to hold them concentric if you were going to make your own on the lathe because they are so thin walled. You could not put them in a 3 jaw or 4 jaw chuck because they would distort from the squeeze of the chuck. When I get the new Dunlop D 803 GP installed I will weigh the front wheel without the brake backing plate and let you know what it weighs. I'm sure the rim is wider than a TY rim, but it might not weigh that much more. Made my own handle bar risers to get my standing riding position to be more upright. Tomorrw is my 70'th birthday, so I can't be riding all hunched over for too long Thanks for all your help! Wish you were in North Idaho- you could see my pile of parts! Or we could go fishing!
  16. The only difference I can see is that at the bottom of the right hand slider, there are two studs sticking out of the bottom of the fork leg to hold the axle clamp. If you look at the parts manual online: https://www.yamahapartshouse.com/oemparts/a/yam/5004177af8700209bc784bdc/front-fork There are no visible studs showing on either fork leg. \ Could be another "artist" problem as you mentioned before about the springs. There are also possibly some differences in the internal parts between the diagram and what is on my work bench but I would have to line everything up and take another look. However, I am more than willing to try the TY springs if I can find some later on. Spacers are no problem. I have a good ol South Bend 10K metal lathe. What would the Race Tech Gold Valves do for this situation? You are indeed the Yamaha Guru! Don't know if the YZ setup is any heavier? I think the front rim is wider than the one on the TY. Had another look at the Falcon rear shocks today. I do indeed have the 50 pound springs on there. And the shock body should be on top to get the shock action working both ways 100% if that is the desired result.?? I might adjust the spring clip all the way down (up) and see if I can get the 50% sag situation to happen. I can get a used TY front wheel and hub for about $100.00 US, but the condition could be a problem. Worth it? Also I can get some Very used looking TY forks (pitted and worn chrome on the tubes) Seals shot for 170 Us, but there again, condition looks like a problem.
  17. Yes, tried to cancel the order for the 15 wt and swap it for some 5wt oil. Hope that sounds better? As far as the source of the forks- Close as I can figure out it looks very similar to the 1974 Yamaha YZ 250 setup.Not 100% identical, but close enough. The axle is positioned on the centerline of the fork legs and anything newer than about 75 has the axle in front of the centerline. As soon as the seals and the new 10mm Allen bolt comes in I can at least put the forks back together (less springs and oil) and check for clearances around the new TY style front fender. From looking at the parts breakdown of the TY it looks like they use two sets of springs instead of just one big long one in each fork leg. Don't know if it would be possible to change out the MX springs for some TY springs? I hope so because the wheel hub I have now is also from a YZ and it does not fit a TY fork leg like it is with it's tennon and notch situation on the brake backing plate I have now. Buy a trials bike? Sure send me some $$$. As long as it is taking for the engine overhaul, paint, new seat, fenders, fork modifications, it would be nice to have another bike to ride !!!
  18. Feetupfun! Great info and good news. I was afraid the triple clamps were not TY in which case it would throw off the rake and trail. The lower fork legs have a TYB sticker on them. I guess they still could be from an MX or YZ Yamaha as the TYB rep said that TYB sells to OEM source makers. I was able to steer and manouver fairly well with the old high fender setup and with the fork tubes sticking up out of the top triple clamp about an inch and a half before I took the bike apart for the engine overhaul. The new fender is a TY replica from DC plastics and it looks pretty authentic, so I'm hoping I can get it to work with the new brackets I made. Lots of things to do before I can mount the new fender it though, as I need some dry weather so I can paint the frame and swing arm. Should happen next week I hope. I ordered the new front tire, some fork oil, and some new fork seals in the last couple of days. I guess I will wait for the seals and get the forks back together before I try and mount the new fender. It might be easier to have the bike on it's wheels and just leave the fork springs out until I can see how far the wheel moves up with no springs installed.? The rear shocks are Falcon brand and 13 5/16" center to center or 338mm. Is that longer than stock? How much ground clearance do I need for novice trials? Had to drill out one of the bottom allen screws to get one of the fork legs off. The threads were stuck to the innards of the fork metering rod and would just spin and not let the allen head screw back out. Somebody had put some yellow goop on the threads of the allen screw and it grabbed the metering rod threads permantly!. I ordered some 15 weight oil. don't know if that was a good choice or not, but gotta start somewhere. There is a small captive steel "washer" at the bottom??? end of the main springs( same OD as the spring OD) -looks like a small top hat with a hole in the middle. Is that supposed to be at the bottom of the spring or the top end? Thanks for all your help!
  19. You have raised a good point about the clearances behind and above the new fender that I had not thought of. . Fortunately, the new brackets are somewhat adjustable up and down the lower fork legs so the fender can be adjusted up or down about an inch or so, and also the fork tubes themselves are about an inch and a half longer than they need to be. These are TYB forks and the last 2 inches at the top of the tubes looks to be a separate piece, although they have resisted my best efforts to unscrew them. I can't tell if the triple clamps are Yamaha, or they have also been swapped out for the TYB. I will include some pictures here and maybe you can tell if they are Yamaha triple clamps? I had to replace the lower balls and races inside the center post, and I ordered Yamaha parts for that and they fit the frame and the center post perfectly, so i think it's just the fork legs and front wheel assembly that was swapped out. ?
  20. Apparently there are two models of Dunlop 803 series tires. there is the straight D803 and the D803GP for about $20.00 more. So due to my size limitations and the advice on here, I went ahead and ordered the 803GP tube type model. This will help me finalize the position of the new fender so I can drill the new holes in the exact spot they need to go and also make sure there is enough room for the expansion chamber and some mud on the tire. What would be a good height above the tire front and rear?Thanks for all the good advice!
  21. Not looking for a crossover tire, just for trials use, but thanks for the input.
  22. Lineaway, I don't know if the new metric sized tires will fit the english 2.75x 21 front rim. The Dunlop 803 GP seems to only be available in metric sizes ? Lineaway, I'm in the states and it's good to know that the metric marked tires are the same thing. Your link is showing a fairly low price too, so I will check out the shipping prices and see if that still makes sense. The michelins here in the states are only showing the metric numbers for some reason. Kind of confusing. Will do some calling around tomorrow. Good info and my "brackets" are special to the forks on this bike. They mount right to the fork legs to accomodate the TY style fender, but the fork legs on this bike have no mounting boss for the bolts from the fender, so it's off to the mill and the lathe making lots of aluminum chips to make something that will do the job. Not the easiest trick I've ever done either! But it beats buying more forks!
  23. By the way, I'm making my own front fender brackets (long story), and I have a brand new TY style front fender to mount. How much space should I have between the tire and the inside of the fender?
  24. I have a TY 250 which had knobbies and a fat seat on it. The front fender was mounted high up under the triple clamps. All this is being changed out in favor of trials riding. wish me luck!
  25. From just a little research I did just now, the only 2.75 x 21" tires made for trials are made by IRC. If you know of any Dunlop 803 GP's or Michelin competition tires that are sized in inches, that would be good to know.
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