Motorcycle classics magazine. Steering the MV3 -500

J.A.W. said:

Curious, those diminutive M.V.3 chassis dimensions are very similar to the original RD 350.. Coincidence?

Click to expand...

Coincidence or not, all the RD 350 Yamahas including the 250 &350 LCs (Don’t know about the YPVS) start to wobble at the handlebars at 95mph I suspect that the MV doesn’t, maybe because it usually comes with an hydraulic steering damper fitted.

BTY it appears that 6 MV 500s were built in Italy and 6 in the UK this must make it the most copied muti-cylinder GP racer right now.

A two stroke has extremely different characteristics to a fourstroke as far as the frame and geometry are concerned. I know some of the guys like to fit watercooled MX motors to Honda RS125 frames, and the combination seems to work. But a two stroke has very poor torque characteristics, and the way you ride it is different. In most cases it is 'point and squirt', not tip toeing nimbly around corners working on the opposition. ( Except for an RS125). I know Colin Seeley built the Yamsel which was successful, but my approach has always been totally different with the two types of bike. I am posting a pic of my 'folly'. It is a copy of an Egli two stroke fra me intended for a TZ750 motor, fitted with an H1 Kawasaki based motor with RD350 barrels. It has TZ750 port timings and is 600cc capacity. It is not as simple as merely fitting a motor in a frame. I've used plates to get the motor high enough to get the chain line right, and still have the correct rake to suit the 17 inch wheels.

I"ve noticed that skinny large OD rims/tires hook up better when at extremes of lean as it was on 17" balloon tires I learned mc and my limits of control - as my un-tamed Cdo's went out of control before tire grip became a limiter [except on THE Gravel] so didn't learn much but to back off before crashing in nic of time. Almost guit the clunker Commando but Bob Patton via Tom Davenport saved me - plus accidental engine combo that could about equal the racers - amazingly to me and confused contesters.

Someday hope to find out for sure what the best tool for harsh cornering is up to 150 mph or so. There's great competition to face that does impress me deeply on what I need to face up to. Need suggestions on how to demo Peel capasity to tempt others to surpass and improve on her .

Aco , "a 2-Stroke has very poor torque characteristics"- not quite old boy, that hit is what chainsaw/outboard boat users depend on to get good bite, & up on the plane..
I put an H2 mill in a Yam 350 LC chassis, the added mass on the front [static & dynamic] improved the steering/stability-took away that flighty feel at speed.
Hobot, I concur with the subjective feel of diameter vs width - tyre footprint characteristics you have described.