Yamaha RD350 meanderings.

@chak feels a bit that way sometime....

It's always a bit of a disaster to try and hurry this stuff, which is exactly what I'm doing. Anyways, I attempted to get the engine buttoned over the weekend. I doweled the heads to the barrels to try and keep the head perfectly concentric. As standard, they can wander quite a bit which gives you inconsistent squish clearance. Normally, it's 2 holes through the head into the gasket face of the barrel - I tried a different method and it worked ok.

After that, I fly-cut the lip off the top so I could run the full width RD400 gaskets which seal much better and don't distort the heads. At this point, I was all set to bolt it on, and set the squish but to my chagrin discovered that I'd been sent the wrong little end bearings. Boo.

Then I set about pulling off the clutch and primary pinion gears, to change to the 350 ratios. I actually was planning to use a basket and some parts from an old YZ400C MX bike, which has the same ratio, but straight cut gears. On closer inspection though, there is a little damage to the face of one of the teeth on the basket and the idler gear that goes on the back for the kickstart still hasn't arrived. Clutch shelved for now.

So finally, I started welding some of the seams on the cones....not easy! There's only .2mm difference between 20 and 22ga (.98 to .78) but it really makes it harder to weld. I was running just a dribble of acetylene out of my smallest tip and even then, you can't hang around. As is typical, I got my eye in a bit better after the first couple, so I might go back and remake any slightly blobby ones. In keeping with the rest of my efforts this weekend, just as it all started going well, I ran out of O2....

Ho hum.

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