bestrcpilot

In the US where I ride the rules are the year of the bike for what class it can be riden in. So a OW10 would ride with the TS class, or 1970 to 1976 class. Well anyway the build is started, going to start with a 1978 dt175 frame and a 1975 ty250 motor and forks and wheels. Building a frame jig this weekend. All of the pictures are loaded into the computer and a set of blueprints are being printed. Got to love CAD input picture and out comes blueprints. If it was built before, we can build it again.

Thanks but I've seen that. Is anyone in the know? Are any of these bikes still around? Or did Yamaha cut them all up? I would love to show up at the local TS trial and see what they tell me if I would be aloud to ride it. I guess I will just have to built one from the pictures on the web.

Hello all I'm looking for any info on the OW10 that mick rode in 74,75,76. I would like to build one. Wonding if the Dt. was a base for it or was the Dt based on it? Thanks

Had the Bultaco M125 out for a run around today. After about 20 minutes it quit running. after checking all normal stuff I checked the plug cap. Now this was a brand new NGK cap and it had 5000k or open. So on goes the old cap back on and the Bully started right up. Never trust a part just because. it's new

Yes it's the kdx220 piston. Sorry about that .

Hello all I 'm trying to find any info on using a rdx220 piston in a ty175. The rdx220 piston has the right size wrist pin 16mm and with bore sizes starting at 69mm. My liner is already at 68mm on my stock engine and I would like to keep using it as the porting is to my liking, but would like to rebore to 70mm and make a 200 out of it. So anyone used the rdx220 piston and what needs to be done with it in order to make it work? Thanks

I've had the same problem. The rubber coating on the reed was not straight and flat it had worn after 35 years. A new reed block fixed it.

I guess I had it wrong. should not answer questions after a couple of beers at night.Anyway enjoy your bike and hope to see you at the trial in Grafton WV next weekend.

Hello and welcome.Your bike is a 348. Look in trials inc and Mavt for trials in your neck of the woods.

11/51 I find to be the best for trials work. I have tried 10/51 and found that it was to low,lots of revs in 1st gear but gives you 3rd gear on some of the hills. Your bike seem to be geared for the road. But then what is the bike used for?

Hello cleaner Yes I set the the top of the forks level with the top of the yoke and I'm using 340mm rear shocks with the top shock mounts moved down. I did find that I needed to use a fork brace, as the forks seem to twist more with the forks lower in the yokes (with ty175 forks) . By angling the shocks the spring rate changes (lighter 50 pd springs act like 45 pd spring). There are pitures of my bike on here somewhere. Sorry For no link but my phone will not let me post links. And the kickstand needs to be longer or use a rock under it.

Tony I find it hard to follow your thinking that by going to longer shocks on a ty175 with the upper shock mounts moved that it will stear like a Harley. By rising the back of the bike with longer shocks you steepen the head angle. It aslo adds more weight to the front wheel. Should he drop the forks down to be level with the top of the yoke Yes. And after moving the shock mount he will have changed the amount of rear sag and by going to a longer rear shock the rear sag comes back to where it should be. I run 360mm shocks with the mounts moved down and find that the bike will out turn most ts. I'm not trying to start a flame war, jusy trying to understand your thinking. thanks

Thanks feetup. That what I needed.

Almost done rebuilding a M125, that I got as a barn find. could someone tell where the kickstand mounts to the bike. I think it mounts to the swing arm on the right side, but The bike did not have a swing arm on it when I found it. And the Alpina swing arm that I'm using does not have a kickstand mount on it as the Alpina kickstand is on the frame. A picture would be great. Thank for any help

To realine the crank,some are held between centers and two dial indicators on the bearing surfaces. And some you rest the bearing surfaces on a set of V blocks and using the dial indicators on bearing surface. Spin the crank and watch the indicators to find the high spot. Then hit the counter weight with a lead hammer at the high spot. But first take the crank out of the centers or V blocks. I've made a jig for the cranks that I do a lot(ty175) the jig holds the two crank halfs while pressing the crank pin in. Hope this answer your question.

I've had some crank pins that will come out at 2 tons on a home made press and some I've had to take into work and use the 50 ton press. Most will come out at with the small home made press. For the ones that seem to be stuck A hard hit with a lead hammer on the counter wieght seem to help them move.

To add more oil to the fire. The size of the size of a air box is only as good as the air flow that it will let pass through it. The stock air box and carb to air box pipe are not the best. The intake pipe has to turn the flowing air 90

I use the rubber floor mats. They come in 3'x3' sheets at the home improvement stores.

Check the reeds and reed block to see it the reeds are sealing to the reed block. Mine would not pull 4 or 5th gear and would not pull a hill. Had to replace the reeds and reedblock, it was running rich at anything above 1/4 throttle. Just a thought

The book calls for a point gap of .020 inch. But I just use that setting as a starting point. I set the the timing so that the points open at .090" before top dead center and not at the book spec of .070" and the only way to do this is to play with point gap as the stock stotor can not be moved. New reeds will help as will a spacer plate between the reed block and the rubber intake boot. Just make sure the reeds are closing down tight to the reed block. a intake rubber from a Yamaha rd350 also as it centers the carb to the reed block and is not offset to the left like the stock intake. Here in the states Bj racing has the parts and in England trails and trial. Are just two of the many. And there is Ebay.

The thinner head gasket is something that has to be made. I used sheet cooper from a model airplane shop. The sheet cooper can be easily cut with a pair of scissors. There are threads that explain the mods that can be done to the ty175 engine, the best mod that I fine that works the best is a new carby. A 40 year old carby is worn out and will never work right. I put a 24mm Mikuni flat slide on mine and it turned a dog into a jewel.

Hi I mean the whole exhust. i started a fire in a big steel drum and put the exhust in the fire and let it burn overnight. Do not try it this way if it's alum. If you get the exhust good and hot like after a long long ride and it still smokes after you shut the motor off then it's oil build up in the exhust.

I run the same oil and also at 50/1 and it does not smoke a lot. Have you clean out the exhust? I found that mine smoked a lot with the old exhust until I burned it out. just a guess

My Ty 175 had the 2 coils together,these are the lighting coils. the smaller one is the lighting coil for the tail light and the larger one is for the head light. These coils are at the 9:00 o'clock postion and the large coil at the 3:00 o'clock postion is the ing. coil

As one of the old grey hairs myself. Get a ty175 and have fun with it. It's the easiest to pick up out of the mud. and lightest of the old twin shocks. I have a Bultaco m125 and a Mont 348 and find the ty175 the one I ride the most.