Flywheel - Less Weight = Less Wait

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- Flywheel -

Less Weight = Less Wait

The question - I linked over to your web page, and was quite impressed. Nice Honda. I too seek all from my motor, it's nice to give the "twins" a run for their money, from a single 250!!! However, onto what my question is. I noticed that your spec's included a lightened flywheel. Who did it, or more precisely where can I find info about lightening it???? I've got a very good machinist at my disposal and have wanted to do this for a while, but didn't know where to take material off. I understand the principles and how it affects the tractability of my motor but I figured that it would be something more to throw into the tuner's toolbox.

The response - The material is removed from the outside of the rotor. Since the pulse trigger is sticking out of the surface you can't remove material across the whole surface. Once the flywheel is trued in a lathe you cut up to the trigger from one side, then up to the trigger from the other side. No material is removed from the front of it. A cut (or multiple cuts) totaling between .075" and .100" is all that is removed (depending on application).

Rick

I can get a "used" flywheel from the scrap yard for about 75 bones and then start whacking away. So you leave the material that is "in-line" with the trigger, and don't bother with milling that off?? Would it be advantageous to radius the corners of the cuts to help prevent cracking??? I've seen the nasty results of a Banshee flywheel cracking apart at 9500 rpm's.

Backcountry

That's right. Leave the material in that area alone. A small radius is always a good idea. It is probably best to attach the flywheel to a trued spindle - one made from a real TRX crank with the key way and threads on the end to tighten it on - or one that is identical to it - and double check it for run out. What is true on the flywheel is the inner surface - the surface which presses against the crankshaft. All balance and truing should be done from this surface. This method would be preferred over chucking the rotor and truing it from there.

Rick

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