Flywheel Lightening

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Silverfang
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Post Sat Mar 07, 2009 5:47 pm

Since i've had to purchuse a new flywheel and soon a new clutch (Thanks Theo325 :D ) I had a thought about getting this fly lightened a bit since it needs re-facing.

How much, if at all possible, can you remove from a M20 flywheel safely considering it will need rebalancing afterwards.
BMW and Opel, both RWD, both german, both good fun
http://www.clockservicing.co.uk/ For any clock repairs try here.
ed325i
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Post Sat Mar 07, 2009 6:33 pm

gcs325i
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Post Sat Mar 07, 2009 6:42 pm

The number that I found, through searching on the zone, to be a safe limit was 5.6kg, When i got mine done it came in at a touch under 6 kg.
UweM3
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Post Sat Mar 07, 2009 7:48 pm

It's not only a question of how much can you take off, it's a matter of where you take the weight out. As more as you can take off on the larger diameter sections, the better.
Jhonno
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Post Sat Mar 07, 2009 9:59 pm

What Uwe says is true.. I have a 6kg flywheel, which revs better than a 4.5kg one for that very reason!
Got cable ties? Get diffin..

Arch roller for hire.

www.zeroexhausts.co.uk

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march109
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Post Sun Mar 08, 2009 8:46 am

This is because the mass that is further out from that axis must, for a given angular velocity, move more quickly than mass closer to the axis.
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hongkongfuey
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Post Sun Mar 08, 2009 10:46 am

i can get them done
if there wern't people like me,
with cars like mine,
who would you put down to make yourself feel better?
Silverfang
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Post Sun Mar 08, 2009 4:11 pm

I've got a machine shop locally who could probably do it.

What the question is now, is does anyone have a design or technical drawing on where the material can be removed from the stock flywheel?
BMW and Opel, both RWD, both german, both good fun
http://www.clockservicing.co.uk/ For any clock repairs try here.
UweM3
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Post Sun Mar 08, 2009 7:10 pm

Silverfang wrote:I've got a machine shop locally who could probably do it.

What the question is now, is does anyone have a design or technical drawing on where the material can be removed from the stock flywheel?
how much is that going to cost you?? A TTV flywheel isn't that expensive.
Silverfang
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Post Sun Mar 08, 2009 10:51 pm

UweM3 wrote:
Silverfang wrote:I've got a machine shop locally who could probably do it.

What the question is now, is does anyone have a design or technical drawing on where the material can be removed from the stock flywheel?
how much is that going to cost you?? A TTV flywheel isn't that expensive.
I don't as yet, I'm getting a quote on it when a friend's got it to said shop, I did look at the cost of a lightened flywheel but at the time i got it, i had a limited budget, still do :(

If it's more than £50 or so i'll only be able to get it re-faced.

I'll wait and see on the costs, reputedly this shop is good on price.
BMW and Opel, both RWD, both german, both good fun
http://www.clockservicing.co.uk/ For any clock repairs try here.
hongkongfuey
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Post Mon Mar 09, 2009 5:12 pm

mine after lightening, it's now at 5.9 kg
Image
Image

a pic of a unlightened one ( not mine forgot to take a photo before)
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if there wern't people like me,
with cars like mine,
who would you put down to make yourself feel better?
Silverfang
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Post Wed Apr 29, 2009 10:51 pm

Update: Flywheel's back from the machine shop, all of 6kg now from over 9kg! :eek: :D

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Front

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Back

And complete setup.... :D :D The clutch cost me a fair chunk but the machining totaled only £40 :D

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One brand new LuK Clutch.
BMW and Opel, both RWD, both german, both good fun
http://www.clockservicing.co.uk/ For any clock repairs try here.
rix313
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Post Wed Apr 29, 2009 10:56 pm

Looks nice how much did it cost to have it machine and balanced? You think thats heavy, M42 one was 12kg!! lol its 6.7 now winkeye
Silverfang
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Post Wed Apr 29, 2009 11:40 pm

rix313 wrote:Looks nice how much did it cost to have it machine and balanced? You think thats heavy, M42 one was 12kg!! lol its 6.7 now winkeye
Did mention in the post, but guess you missed it, the guy did it for £40 all in, and he's done many different flywheels with no problems.

Goes in on the 11th May 8)
BMW and Opel, both RWD, both german, both good fun
http://www.clockservicing.co.uk/ For any clock repairs try here.