How lite can you go with a A+ flywheel

For a standard cast wheel this is about optimum http://universe.websiteactive.com/~ausmini/forums/viewtopic.php?t=28969&highlight=flywheel+lightening

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David L


My greatest fear in life is that when I die my wife will sell my Mini and tools for the price I told her I paid for them!

David, he says A+ so it's probably the dreaded Verto one. I have no idea on those friggin' things... If I ever got one I'd bury it.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

Doc it has not got a verto clutch. Clutch plate and back plate on primary gear side and diapham on release bearing side

I just weighed the last 2 piece flywheel I did. it's 6.1KG.
Yes I know you can go lighter, some people drill holes etc- but this is for road use, light enough IMO.
I also lighten the backplate by making it curved triangular, similar shape to a Wankel rotor. I'll find and weigh one in the morning.

<edit> My Minispares UK catalog says a safely lightened (one-piece?) flywheel is 6.05KG so I'm on the money.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

Mason, I've got a Lyn Rogers lightened one from a mini7 race car sitting on the shelf.....it's more air than metal and he said he probably wouldn't put it in a big bore, but don't let that stop you

OK I just weighed a pair of backplates. Stock one is 2.6KG, my triangularly lightened one is 2.1KG.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

The flywheel i have is 5.7 kg so im going to leave it as it is .Thanks for the advise

whats the advantage of a lightened flywheel - does it only help you get the revs up better??

Do they lose horse power - like a heavy one when it starts moving takes a lot to stop can have more restriction and still turning, where as a light one wont?

Do they have any disadvantages??

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"In two years time your car will be like a lady's clothes, out of date, my car will still be in fashion when I am dead" - Sir Alec speaking to Pininfarina

is it for sale?

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speed costs....how fast do you want to go...

Sure. I was thinking about chucking on my 850 but that's sold, only have the 1380 now and that has a steel ultra light already. Would get it crack tested etc before using it, and maybe have a chat to senior Rogers or even take it to him since you're up that way. PM me with an offer.

Yes it allows the engine to rev out quicker since you have removed mass and it should rotate quicker(I think). However the downside is you lose some low down torque but it is negligible. I have a lightened one in the new engine and it is much of a muchness(static it revs better under load however the dyno showed a little drop in the low torque - you just have to get it there with gearing and changing them higher up the rev range)

I just recently changed the flywheel on the Soob and they tooK a massive 2.6kg out of it. Revs its tits off now but I have noticed a little loss in low range torque when I am traversing the dirty stuff but it gets up to operating revs quicker. It is a compromise I suppose.

Heres a pic of the Soob Flywheel - consider that the original is completely flat from the edge to the centre: They took it off the engine side only and it took them 3 hours just to mill it down(hard stuff this...lol):







Not real good pics but you get the idea

Hooroo

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Rob Forsyth
Miniot!!

It revs hard

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BLOODY HELL!!!!

Nice looking gear there. Do your revs drop off quicker with that setup? I noticed the Touring Wagon goes up quickly to revs but drops back even quicker now...

Again nice gear...

Hooroo

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Rob Forsyth
Miniot!!