A Bicentenial restoration/rescue - '76 RD400

So far, engine out of frame, cylinders honed, things measured. Piston looks great and measures perfect, cylinders cleaned up and measured Ok. But! Ring gap is 2X max, so new ordered. Leak down failed on right main crank seal-to-case joint, so it all has to come apart and get new seals (on-hand). Right now the engine is on its left side to remove ~1/4" built-up road grime.

This thing has 24, 29, and 34 mm nuts on various shafts, so I have had to get some new impact sockets.

My new Brauer electric impact works great!
 
Crank sent out to rebuild. Carbs all clean. Many parts acquired. Next will be to clean paint off of places on the engine (ends of fins, sides of outside head fins) where it doesn't belong. Then, frame gets rolled back into the garage, stripped down, cleaned, and repainted.
 
Yamaha made lots & lots of the RD250/350 & 400.
I think one of the reasons so few are left is so many road-racers learned on one.
They could wad one up, then get another cheap. & wad that one up as well.
My son had a 350 with chambers & low bars that went like stink.
With some suspension work they also handled OK back in the day.
Cheers, Steve
 
Crank is back from the rebuilder. Frame is stripped down for cleaning and repaint. Next week will be busy preparing for a bike show Oct 3rd at church (PM me if you want info - in Powell, TN.) Then, the race to get the tank and panels painted while the low humidity fall air is around.
 
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I have owned RD250s and 350s. I built up a pretty nice 350 about 20 years ago and it ran great! 20 mpg and socially unfriendly with it expansion chambers, port work, bored carbs and reprofiled squish on the heads. Lotsa work and I ended up selling the nice bike in the later 90s for 800 bucks! I decided if I was doing all that work again, I would start with a Vincent or something :p
 
There's a bike boneyard down here by us over in Six Mile.
Not sure if they'd have parts or not, but it's huge. Scrounged parts there for the Stepson's Kawasaki.

In 1976, I bought a brand new Yamaha RD400. Loved it, but in '79 was mature enought to know that I was not mature enough to have it in the Kentucky/Tennessee mountains where I planned to move when I got out of the Navy that summer. So, I sold it to a shipmate. Life happened and it wasn't until '04 that I had another motorcycle. I've had mostly GoldWings since, but always longed for another RD. Things like this are hard to find when you are looking for them. Actually doing a search for a TW200, this bike poped up. Like the folks that would prefer a rescue dog over a breeder's choice pure bred, I prefer a project bike. And this is.

1976 Yamaha RD400 in Chappy Red (that will change to Geneva Green). Engine in frame and a roller, plus a bin full of parts. 360+ miles away. Road trip! Picked it up, spent the night with a cousin, and brought it home. Missing are: brake calipers, mufflers, one muffler boot, air cleaner cover (and element), plug leads, rear fender, rear hoop (called a stay in the parts list), tail light and bracket, all signals. Lots in need of repair, too. Seems to have been stored in the dry except the seat pan. Engine turns over, but didn't test compression.

This should keep me out of trouble for a while.
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There's a bike boneyard down here by us over in Six Mile.
Not sure if they'd have parts or not, but it's huge. Scrounged parts there for the Stepson's Kawasaki.
I've heard about the breaker at Six Mile. Not made it there yet. Need to ride over that way while the weather is nice. Do you ever go to the Time Warp? There was a nice 350 there Tuesday.
 
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I've heard about the breaker at Six Mile. Not made it there yet. Need to ride over that way while the weather is nice. Do you evere go to the Time Warp? There was a nice 350 there Tuesday.
Grabbed coffee there a couple of times over the years.
There's someone here in town that buzzes around on a sweet 350. Always wanted one since High School.
 
No photos today, but the RD400 case mating surfaces are cleaned up (about six hour's work) and the transmission installed and tested that it shifts (one hour's work). Tomorrow the crank goes in!
 
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