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BammBamm 04-12-2001 10:27 PM

Re: Honda RC211V V-5 Pictures
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.

Hafmo 04-13-2001 03:04 AM

Re: Honda RC211V V-5 Pictures
A couple of thoughts. Adding a balance shaft will rob some power and add a little weight, but by making the engine vibrate less the supporting structure doesn't have to be as strong (heavy.) Might be a push from a performance standpoint. As far as using the RC45 as a starting point, it never was all that successful as a race bike. Koscinski managed one championship with it, but that was it. That was a lot of money invested by Honda with not much to show for it.

DataDan 04-13-2001 04:10 AM

Balancing a V5
I don't buy the idea of differently sized cylinders to accomplish balance. Here's another possibility.

Note on the widely circulated photo of the motor that the back cylinders are widely spaced, positioned slightly inboard relative to the outboard front cylinders. That indicates a common crankpin, just like the VF, VFR, RC30, RC45, and just about every other V4 ever made.

The middle front cylinder is then the odd man out. Anyone here familiar with the Ducati Supermono? It's a single based on their 90-degree twin. Only one of the cylinders isn't a cylinder at all. It's just a hole with a mass attached to a connecting rod to balance out the real piston. Perfect primary balance in a single, and thus the ability to rev like crazy without shaking itself to pieces.

My guess is that Honda employs a similar trick in the rear cylinder bank to achieve balance.

draz 04-13-2001 05:31 AM

Re: Hmmm
I'm pretty sure the only reason the swingarm looks bigger on one side is that right side has the cut out for the chain.

El_Flaco 04-13-2001 08:30 AM

Someone said that it sounded a lot like a large, angry V-twin, which could imply a lot about the firing order. Big bang theory for traction? Interesting stuff! Keep us updated, MO!

Bob 04-13-2001 09:12 AM

Re: Honda RC211V V-5 Pictures
what's all that knocking sound?

tlogan 04-14-2001 11:33 AM

Re: Balancing a V5
I am not an engineer and not motor builder either. But I am not sure I buy this either, why add and additional mass of metal in the middle of the engine for balance an evan number of cylinders??? I read many articles on the Supermono, and that certainly was a excellent engineered motor...I agree completely with you on the duc. Anyone heard how many RPM's this motor is supposed to turn? This may answer alot of questions.

BammBamm 04-14-2001 12:33 PM

Re: Honda RC211V V-5 Pictures
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 04-14-2001 12:36 PM

Re: Balancing a V5
That sounds interesting. With all the other cylinders, the balancer could be light and relatively negligable. Someone's thinking...

dg_az 04-14-2001 05:06 PM

Re: RC 211v Rear end pics
I'd guess that the aluminum(?) box under the seat is the oil tank. Undoubtedly it's a dry sum engine.

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