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Tillerman6

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About Tillerman6

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    Advanced Member

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  • Bike
    Yamaha TY 250 A

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    North Idaho (Sagle to be exact)

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  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!
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