TDR 250 rebuild thread
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First off progress has been slow, frame took 3 attempts to clean off all the goop everywhere, on the 250 the 2t oil is filled at the rear of tank under seat. Easy to spill/awkward to get at meaning any overfill runs straight down the centre of the bike. Have found a powder coaters hopefully and taking there Tuesday to check out.
Partial engine strip to assess any problems, apart from being in a right state cosmetically ,looking good internally. Cleaned off before disassembly but generally better than expected. Bores are good and barrels ported, as per receipt I have from Stan Stephens. Some hatching still visible so limited mileage methinks from being done, although power valves need a good sorting. Going to replace the crank seals and refinish engine cosmetically, refurb of oil pump all arranged, started ordering parts (gasket set, oil seals, new small end bearings, etc).
This will be a long build so I'll post up when any progress made.
http://imgur.com/gallery/R0EIi30 -
Its a twin cylinder powervalve engine as used in the tzr (some models), has to be twin expansion pipes that cross each other in front of barrels. Power output standard was around 50hp, with ported barrels no idea? I'll have a good look at carbs when I get to that stage and see if they have been altered (jetting).First registered December 91 so later in production run (1988-1993). Have ordered all new seals and some new engine case bolts (bolts underneath heavily corroded, horizontally split cases), all new Yamaha parts, some on back order. Found a powdercoaters less than 5 min away from my house, reccomended by friend with the lc that featured I one of my historic posts. Dropped frame off and taking barrels and cylinder head there tomorrow for vapour blasting. As it turns out last company I used that I was less than impressed with is no longer trading, karma eh!
http://imgur.com/gallery/UHHgzLq -
Barrels and ylinder head dropped off for vapour blasting, pistons and powervalves cleaned. Historic damage to slave powervalve visible, looks like rings have contacted edge of powervalve sometime. Checked prior to strip down and not visible in dirty photos. Best guess is powervalve linkage from driven powervalve to slave failed at some point allowing it to rotate at will. Existing linkage fell apart when I removed heads (have received new one for rebuild)
Did buy a new tool a few weeks ago that deserves a mention, 18v Dewalt impact wrench, should have bought one years ago!
Powervalve cleanup https://imgur.com/gallery/LBJeRzq -
When I bought the TDR it had the popular "upgrade" of TZR wheels, I picked up some refinished original wheels at the same time I bought the bike and stuck them in the loft. One of the reasons for the TZR wheels is the far better choice of tyres, the standard ones are 18" and 17", leaving a realistic choice of 2 brands, Bridgestone BT45 or Avon Roadriders, checked the reviews for both and Bridgestone the obvious choice .
Have ordered the spindles and spacers to suit so all ready when needed.
Tdr250 wheels https://imgur.com/a/ZmDZapu -
Collected my frame, barrels and cylinder head today, very happy with how well its come out. Still waiting for some parts from Fowlers for bottom end of engine on back order, did receive suitable wheel spindles from Greece with correct spacers for original wheels though. Want to get decent shock or new one in the next couple of weeks though, can lock myself in garage over the Christmas period then. Do intend on a Christmas day ride on something though, always used to do it years ago but lost the habit in recent times.
https://imgur.com/a/dgA4UaH -
@calum It's a standard powder coat colour, graphite. A shade darker but a very close match on the finish. The best recoat of a frame so far, but I did explain I wanted a premium job doing and paid a bit more to achieve what I wanted. Will be taking other parts needing refinishing soon.
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@calum It has got a subdued metallic finish, much like the original . In the flesh it looks impressive, factory fresh. As with all powder coating the vin on frame is somewhat diminished but the TDR has a data plate that rivets to side frame tube so no moans from the mot tester hopefully
