Flywheel Fin Lenght

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chris2470
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I was looking into the possibility of also getting my SIL flywheel lightened and balanced and at this point it would make sense to decrease the fins to Italian length to remove some extra weight. If I was to do this would it still be OK to fit my Indian spec cover. If not and I need a thinner cover will it still fit flush to me existing head cowling. Or as I fear they will both need to be replaced as a pair.
Any input will be greatly appreciated before I take the plunge.
Best Regards

Chris
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Doom Patrol
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It sounds to me the easiest answer to your problem Chris is to get it lightened and balanced by all means, but leave the fins as they are. It won't save you much in the way of weight if you get them trimmed and you can still use your existing cowls.
WINTERMODEL150
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yeah i agree keep fines standard length ,bigger fins means more cooling of the cylinder,you can also weld the inner boss together as these sometimes let go on a high performance engines.

Dean.
OzOAP
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Was told ages ago that a 'tall fin' Indian doesn't cool any better than a 'Short fin' due to the air gap between the fins being the same.
I've modified loads of Indian flywheels by milling every other fin off but leaving them std height, along with spinning a bit off the back to an overall weight of 2kg.
Have had no problems with overheating.

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Doom Patrol
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That's interesting Stirling. What led you to try that approach in the first place? Was it simply a weight saving? Actually, if you consider the AF lightened flywheels that people fit which are both smaller and with fewer fins they don't appear to have any problems with over heating. And if they don't I very much doubt yours would. I'd be interested if anybody else has any comments to add to this.
OzOAP
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You dont save much weight by just milling the fins.
A mate gave me a flywheel and asked me to do it, thought "f@@k it, it aint going on my engine, so I dont care if it over heats"
He put it on his TS, no problems.
Must have done bout 15 now, all various specs, ally kits, iron barrels, ect.
Would be interesting to try one without lightening the back. See if the reduced 'finning' helps throttle response.
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