No sweat Colin, When you dig into the F7 a bit and see what you need, let me know what you feel like discarding. As I said, just a (more or less complete) motor would be a place to start. Pat.
Jon lives in my 'hood. If I get a chance in the next coupla days, I'll wander over to his place, get him to boot it up and give me his 5 cents worth and post what he says. Pat.
Have had my second brush with an F7 - the price is higher than I want to pay, considering I'll be discarding most of it and... the transmission had so much water in it, the oil had turned milky... Oh well - there's still my daughter's 175 twin if I change a few things on it to make it P1-legal... Pat
Right you are about DS7 cases - horizontally split, DS6 vertical split. Not polyester poisoning, more like Pabst overdose LOL. Anyway, back to P1: get to look at the Kaw 175 next week - I'll let you know how it turns out. Pat
Hey Jeremy, Not disputing your DS6 comment, but the YDS-3 and YDS-5 cylinder base gaskets are the same P/N, so shouldn't the DS5 cylinders fit on the DS3 cases... which was my suggestion wan't it? Ya the DS6 stud spacing was the same as the RD's up to the RZ, wasn't it -the "notorious" DS6...
The YDS-3 would be a fun bike, just a little difficult to keep the cast iron cylinders from seizing at racing speeds. I've also heard of the crankshaft-mounted clutch giving problems at high rpm's (TD1's had a similar problem) but the fixes must be known as there are a number of them still being rac...
Jeez Brad, Just when I was talking to the UK Bantam Club about a 175cc BSA Bantam Road Racer...with plunger rear frame, no less... Pat PS thanks I'll check it out
Ya Pete, But your bike was a piss-poor enduro bike and the XT500, not a whole lot better. Both made nice street bikes with the ability to take an occasional wander down a cowtrail or gravel road and not come unglued. In stock form, they were excellent for getting your ass handed to you if you were e...
Brad, I stand by my comments. Yes, Yamaha built rotary valve road racers (RD56 for one) as well as their 125cc twin and later 4 cylinder 250cc race bikes. If any of them ever showed up at a VRRA grid, it would be amazing. Yes, their (smaller cc) street bike line was rotary valve (50, 55, 60, 80, 100...
The fact that the rule book forbids Noguchi stuff means that you're at a disadvantage with the CT175 no matter how much you carve up the ports and shag around with the bike. The F7 is a rotary valve and can really be made to run, especially if you can find or can clone a "Skunk Worx" intak...
Hi Alan, Love your RD56 roller and the YR-1 engine is great (I've owned a YR-1 for 43 years). I began something similar a number or years ago - but ersatz, stuff built to resemble the Z608, not the real thing like yours, sold a lot of the bits off ages ago. The only thing you might have trouble with...