The SR500 sidecar build - a motorcycle can't be single cylindrical and four-strokey enough (part 2)

 So this little SR500-gem came back to me, because it had developed a nasty gearbox issue or in other words: it wouldn't shift. Aside from that the engine had to be taken apart as it was left open for a while and lots and lots of saw dust found its way inside. In the parts bin also was a "new" cylinder and piston, which had some marks in the liner. (Which after a quick up and down with the hone were only cosmetical.) Also that new cylinder has got a full-blown strain-relief setup in place, which should help with reliability a bit.

Time to tear the engine down. (It was stored like this w.o. a sidecover for a while.)

Piston looking rather good. (Standard-size)

The clutch lever needle bearing wanted a good clean, some grease and a new seal.

Stripping down those old Yamaha singles is truly a breeze.

So the shift drum selector finger was the culprit - one could have done that without splitting the cases, but considering the amount of dirt that was inside...

Lower clutch lever was well mangled, welded up the hole with some stainless filler and then ground it back with a finger sander. Let's see how long this fix lasts.

5th gear looks pretty terrible, so I guess this one will be replaced rather sooner than later. 

Oil-pan got a goooooooooood cleaning and was sanded flat on glass as it was "contoured" like a 3d map of the Andes. 

Bit of gasket goo ...

... bit of clutch ...(I may have installed the oil-pump drive sprocket the wrong way round - still have to investigate on that one.)

 ... and a bit of sidecover. And there's a shortblock.

A bit of paint slathered on the flywheel, which is later removed and only stays in the grooves, makes checking timing a lot easier. 

The fact that TR1/XV11 engines and SR500s share the same valves, meant that I could just quickly sneak in new valves.

Now one wouldn't put them in, without polishing them up to a mirror finish, right?

Bit of a touchup on the ports - nothing fancy, because we're not building a race bike. Just a bit of love to remove casting flaws.

Black shmoo, because style matters.

Aside from a massive oil-leak (it does help, if you tighten the oil-feed to the cams), the old girl burst into live and made a beautiful racket. 

 

The oil-leak was an easy fix, but the clutch issue (not disengaging), still persists and I have to dig into that one. Aside from that the following posts will mostly deal with appearance matters, until we can finally dig into fitting the actual sidecar to the bike.