[BammBamm]

Re: Hmmm

The swingarm appears smaller on the left hand side because of the chain passing through it. The exterior dimensions are usually the same. The solid side is strong due to being solid, so it can be light, but the other side requires extra bracing due to the hole causing stress concentrations.

 

[BammBamm]

I heard this too, but at a displacement of approx 940cc. Honda has years of data for 750cc x 4 cylinders, so if you add a fifth of the same displacement, you get 937.5cc. Basically it's a RC45 motor with an extra cylinder. They spent thousands of man hours on bore/stroke for the 750cc motor, so they can use this data rather than starting over with minorly larger cylinder bores/strokes.

 

[BammBamm]

Engine balancing has nothing to do with the size of the cylinders. It has to do with phasing, weight and couterbalancing via the crank and coutershafts. The Modenas is a V-3, and all the cylinders are the same size. If your theory is correct, the single would be double the size of the other two cylinders in the v, and that is simply not correct. In fact if the cylinders are different sizes, the power pulses would be of varying magnitudes making the engine very difficult to balance with varying speeds and throttle openings. It makes more sense that the cylinders would all be the same size and that the engine uses a complex phasing balancing process. There is no primary balance anyway as the V isn't 90 degrees.

 

[BammBamm]

Bigger cylinders, more mass. There is an ideal balance between bore size/stroke/piston speed/friction, and Honda thinks it is close to the RC45's size. I think they just added another cylinder of the same size, and have a counterbalancer to offset the unbalance. Two cylinders up into the frame where narrowness counts, three below.



If the bigger cylinders worked, Harley's would be rocketships, but that aint the case.

 

[BammBamm]

It wasn't successful against bikes with a 250cc advantage. Everything is even in GP rules as far as 4 strokes are concerned. Honda was very successful against the other 750's.

 

[BammBamm]

Re: Balancing a V5

That sounds interesting. With all the other cylinders, the balancer could be light and relatively negligable. Someone's thinking...