Tillerman6 Posted May 4, 2020 Report Share Posted May 4, 2020 So with all this unwanted "time off" I decided to try and put my old TY 250A back together. I don't have a shop manual for the A, just the B model, and the B model shop manual calls for 3 special tools to re-install the crankshaft. Spacer (looks like a very large washer) P/N 90890-01016 Crank Shaft Setting Pot P/N 90890-01012 - Looks like a tube about 6" long and 1.5" diameter with a large flange at one end. Crank Shaft Setting Tool P/N 90890-01017 Looks like a special threaded rod about 6" long. All this can be seen on page 110 of the TY250B shop manual from Cycleserv publications, but I don't know if these tools will work on the A model or not? Also- I have a lathe and a mill- If somebody has the time- can you please measure your tools and let me know the dimensions? I could make my own most likely. Much thanks for any advice or tips that you may have! Tillerman6 po Quote Link to comment Share on other sites More sharing options...
feetupfun Posted May 4, 2020 Report Share Posted May 4, 2020 1 hour ago, Tillerman6 said: So with all this unwanted "time off" I decided to try and put my old TY 250A back together. I don't have a shop manual for the A, just the B model, and the B model shop manual calls for 3 special tools to re-install the crankshaft. Spacer (looks like a very large washer) P/N 90890-01016 Crank Shaft Setting Pot P/N 90890-01012 - Looks like a tube about 6" long and 1.5" diameter with a large flange at one end. Crank Shaft Setting Tool P/N 90890-01017 Looks like a special threaded rod about 6" long. All this can be seen on page 110 of the TY250B shop manual from Cycleserv publications, but I don't know if these tools will work on the A model or not? Also- I have a lathe and a mill- If somebody has the time- can you please measure your tools and let me know the dimensions? I could make my own most likely. Much thanks for any advice or tips that you may have! Tillerman6 po PM reply about using a flat tool sent and yes you can easily make the tubular tool that Yamaha shows if you have a lathe. Yes the LH end of the A model crank is the same as the LH end of the later models. The RH ends differ slightly because the A has a spline drive and the later models have a key drive 1 Quote Link to comment Share on other sites More sharing options...
Tillerman6 Posted May 4, 2020 Author Report Share Posted May 4, 2020 Feetup Fun and Majesty, Great advice and nice book! Majesty- looks like I need the DT250A/360A Service Manual after all. Feetup fun- I will take a closer look and see if my tubing stock is about right for that tooling. Quote Link to comment Share on other sites More sharing options...
majesty Posted May 4, 2020 Report Share Posted May 4, 2020 Sorry Mr T Can't help with any DT manuals. Good luck Quote Link to comment Share on other sites More sharing options...
Tillerman6 Posted May 4, 2020 Author Report Share Posted May 4, 2020 16 minutes ago, majesty said: Sorry Mr T Can't help with any DT manuals. Good luck Majesty- That was still a big help! The TY manual You sent said on page34 that the engine overhaul information is actually in the DT250A/DT360A 1974 manual. I found a digital download on Ebay for $7.00 Apparently the DT series is pretty close to the TY series in the 1974 model year. 1 Quote Link to comment Share on other sites More sharing options...
Tillerman6 Posted May 6, 2020 Author Report Share Posted May 6, 2020 On 5/3/2020 at 11:31 PM, feetupfun said: PM reply about using a flat tool sent and yes you can easily make the tubular tool that Yamaha shows if you have a lathe. Yes the LH end of the A model crank is the same as the LH end of the later models. The RH ends differ slightly because the A has a spline drive and the later models have a key drive So today I mounted the crank in my lathe between centers to get an idea of any problems before I start ordering parts (mostly new seals). i didn't get very far and the wife wanted to put up a dog fence, so off we went. After we installed the fence I was pretty tired and just putzed with the front fender mounts. This bike has the forks off a DT or an YZ, so there are no mounting points for the bolts that hold the front fender on. So I made up some new split ring clamp on ones from scratch. But they were too tight and I spent all afternoon fitting them to the fork legs. So that's done, but I still have to mount the aftermarket fender. This type of fender is traditional on the TY's but I don't have one to copy. Do you know about how much room there is between the front tire and the inside of the front fender? It will be tricky to get the spacing right with that slippery plastic fender so I've got the bike on the corner of my table top work bench with the front forks hanging off the edge. If I put the front wheel on, it should be possible to figure out where to drill the holes (I hope) Tools- for the crank installation tool - The manual has no dimensions for the Yamaha tool, But it looks like the tube tool sits over the left end of the crank and rests on the inner race of the main bearing? That way there is minimum strain on the bearing. but you need a threaded rod with a female nut on the business end to attach to the magneto end of the crank and another nut to take up the slack. I have not had a chance to unpack all the little paper packages of engine parts I got back from B & j engineering. I'm hoping everything is there. Some of the shop manuals show a shim that goes on the right end of the crank, but some others don't. Did your 250 have a shim on the right end of the crank? it would be right against the right hand flyweight if it is there at all. But don't bother looking if your engine is not torn down of course!! Tillerman6 Quote Link to comment Share on other sites More sharing options...
Tillerman6 Posted May 14, 2020 Author Report Share Posted May 14, 2020 On 5/3/2020 at 11:31 PM, feetupfun said: PM reply about using a flat tool sent and yes you can easily make the tubular tool that Yamaha shows if you have a lathe. Yes the LH end of the A model crank is the same as the LH end of the later models. The RH ends differ slightly because the A has a spline drive and the later models have a key drive So the crank is out for an overhaul. I would assume that you use the tube type puller on both ends of the crank? Seems a bit tricky, but some folks are obviously doing it. And what is this about a "flat tool"? By the way have you done this yourself? I mean re-install a crankshaft on a 175? Quote Link to comment Share on other sites More sharing options...
feetupfun Posted May 14, 2020 Report Share Posted May 14, 2020 Just now, Tillerman6 said: So the crank is out for an overhaul. I would assume that you use the tube type puller on both ends of the crank? Seems a bit tricky, but some folks are obviously doing it. And what is this about a "flat tool"? By the way have you done this yourself? I mean re-install a crankshaft on a 175? The flat tool is what I described in a private message after you asked me about how to do the job. I don't use a tube type puller. Yes I've pulled in many TY175 cranks with a flat tool. Quote Link to comment Share on other sites More sharing options...
feetupfun Posted May 14, 2020 Report Share Posted May 14, 2020 On 5/6/2020 at 1:14 PM, Tillerman6 said: So today I mounted the crank in my lathe between centers to get an idea of any problems before I start ordering parts (mostly new seals). i didn't get very far and the wife wanted to put up a dog fence, so off we went. After we installed the fence I was pretty tired and just putzed with the front fender mounts. This bike has the forks off a DT or an YZ, so there are no mounting points for the bolts that hold the front fender on. So I made up some new split ring clamp on ones from scratch. But they were too tight and I spent all afternoon fitting them to the fork legs. So that's done, but I still have to mount the aftermarket fender. This type of fender is traditional on the TY's but I don't have one to copy. Do you know about how much room there is between the front tire and the inside of the front fender? About 20mm with an inflated Michelin trials tyre. Because you have non standard forks it would be a good time to check how much clearance there is with the forks fully compressed (springs removed) between the top of the guard and the underside of the lower triple clamp. It will be tricky to get the spacing right with that slippery plastic fender so I've got the bike on the corner of my table top work bench with the front forks hanging off the edge. If I put the front wheel on, it should be possible to figure out where to drill the holes (I hope) Tools- for the crank installation tool - The manual has no dimensions for the Yamaha tool, But it looks like the tube tool sits over the left end of the crank and rests on the inner race of the main bearing? Yes That way there is minimum strain on the bearing. but you need a threaded rod with a female nut on the business end to attach to the magneto end of the crank and another nut to take up the slack. Yes I have not had a chance to unpack all the little paper packages of engine parts I got back from B & j engineering. I'm hoping everything is there. Some of the shop manuals show a shim that goes on the right end of the crank, but some others don't. Did your 250 have a shim on the right end of the crank? it would be right against the right hand flyweight if it is there at all. But don't bother looking if your engine is not torn down of course!! The shim goes between the RH crank wheel and the RH main bearing Tillerman6 Notes added to your questions Quote Link to comment Share on other sites More sharing options...
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