All the way back in 2012 I picked up this bike. It belonged to the guys dad who had recently passed away. He knew nothing about it and just wanted it gone. $100 later and it was mine.
All that's left of it is the engine. Everything else except for the wheels and brakes has been sold off over the years. This thread will document the teardown, inspection and buildup of the engine. Kinda lazy on the pics, but it was a nasty, grody mess on the outside and it was locked up. I recall that shortly after I got it home I squirted a healthy dose of P B Blaster down both plug holes. Glad I did.
First thing I did was squirt some more Blaster down the plug holes and see if I could get it to spin. To my absolute amazement, a wrench on the rotor nut and a good smack and I had movement. A few rocks back and forth and it was free. Without a doubt the easiest "unlock" I've ever done. Sounds promising, eh?
The rocker box was already off because I robbed the cam out of it ages ago. Head and jugs came off with no fuss. The jury's still out until I do some cleaning and measuring, but they look to be in pretty good shape. Currently coolin' their heals in the wash tank.
Pistons look good. I know it looks like a lot of scoring on the skirts, but actually there's very little. This damn Pixel magnifies everything. Oddly, the top and bottom rings are seized in their grooves... but the second ring isn't. That's a head scratcher. There we NO needle bearings in the con rod little end, so as far as I know that makes this an XS1B engine and not the XS1... correct??
On the left side the rotor still looks in good shape.
Also on the top end... there was evidence of red RTV, so the top's been opened up before. Pulled the right cover. There didn't appear to be any signs it'd ever been opened before, but I found this laying on the bottom of the cover.... the nut and worm gear for the tach drive. No signs of the tach drive shaft or other bits. Odd huh? Luckily the oil pump gear stayed in place all by itself.
The clutch was similarly untouched. Funny, there was a discussion here today on the rubber rings Yamaha installed in the clutch... the ones everyone shit cans when they replace the discs.
Rolled it over and split the cases.
Spun the tranny through all 5 gears and everything shifted smoothly. Just a visual inspection, but the dogs and gear teeth almost look like they've never been used.
A bit dirty, but the crank looks to be in excellent condition. There's still copper showing inside the little ends and all the bearings feel tight.
Overall, a pretty easy teardown. I'll get everything cleaned up and start some measuring. All in all, I think I got pretty lucky with this one... it appears to be a pretty easy rebuild... not to jinx myself or anything. "Sides, I ain't superstitious.
Oh, and this motor's already spoken for.
All that's left of it is the engine. Everything else except for the wheels and brakes has been sold off over the years. This thread will document the teardown, inspection and buildup of the engine. Kinda lazy on the pics, but it was a nasty, grody mess on the outside and it was locked up. I recall that shortly after I got it home I squirted a healthy dose of P B Blaster down both plug holes. Glad I did.
First thing I did was squirt some more Blaster down the plug holes and see if I could get it to spin. To my absolute amazement, a wrench on the rotor nut and a good smack and I had movement. A few rocks back and forth and it was free. Without a doubt the easiest "unlock" I've ever done. Sounds promising, eh?
The rocker box was already off because I robbed the cam out of it ages ago. Head and jugs came off with no fuss. The jury's still out until I do some cleaning and measuring, but they look to be in pretty good shape. Currently coolin' their heals in the wash tank.
Pistons look good. I know it looks like a lot of scoring on the skirts, but actually there's very little. This damn Pixel magnifies everything. Oddly, the top and bottom rings are seized in their grooves... but the second ring isn't. That's a head scratcher. There we NO needle bearings in the con rod little end, so as far as I know that makes this an XS1B engine and not the XS1... correct??
On the left side the rotor still looks in good shape.
Also on the top end... there was evidence of red RTV, so the top's been opened up before. Pulled the right cover. There didn't appear to be any signs it'd ever been opened before, but I found this laying on the bottom of the cover.... the nut and worm gear for the tach drive. No signs of the tach drive shaft or other bits. Odd huh? Luckily the oil pump gear stayed in place all by itself.
The clutch was similarly untouched. Funny, there was a discussion here today on the rubber rings Yamaha installed in the clutch... the ones everyone shit cans when they replace the discs.
Rolled it over and split the cases.
Spun the tranny through all 5 gears and everything shifted smoothly. Just a visual inspection, but the dogs and gear teeth almost look like they've never been used.
A bit dirty, but the crank looks to be in excellent condition. There's still copper showing inside the little ends and all the bearings feel tight.
Overall, a pretty easy teardown. I'll get everything cleaned up and start some measuring. All in all, I think I got pretty lucky with this one... it appears to be a pretty easy rebuild... not to jinx myself or anything. "Sides, I ain't superstitious.
Oh, and this motor's already spoken for.
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