Author Topic: Mean Streak rotor for the 17" rear conversion  (Read 897 times)

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Offline cafefill

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Mean Streak rotor for the 17" rear conversion
« on: January 25, 2013, 02:49:32 am »
I had the rotor mounting surface for the Mean Streak wheel turned down this past weekend by a machinist friend of mine. That part went fine. Then we got to the Mean Streak rotor, which needs to be turned down to 280 mm. There was also another journeyman machinist there, and they both agreed that turning down the Mean Streak rotor to the 280 mm was a mistake.  Turning it down will cut into the most outboard drilled holes in the disc, and they feel that doing this will make it prone to cracking. Any thoughts out there on this? I'd like to get off cheap, as I got the disc free with the wheel, but not at the risk of safety.
Cafefill
« Last Edit: January 25, 2013, 02:54:24 am by cafefill »

Offline GF-in-CA

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Re: Mean Streak rotor for the 17" rear conversion
« Reply #1 on: January 25, 2013, 03:31:13 am »
IMO, the rotor would not be any more or less likely to crack than without modifying it.  The radius of the holes is not small enough to be a concern for stress risers, plus the stress in that region is relatively low, so I would not worry about it.  I know of several owners who have done this, and have not heard of any problems as a result.  Of course, if you are still uncomfortable, there are other options that will work, so do what makes you feel safe. 

It will be hard on the tool they use to cut it, though, so you might want to throw in a couple of extra six packs of the good stuff for your friend.   :)

HTH,
Gary F.

1998 ZGX1100
Central Valley California

Offline Bob_C_CT

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Re: Mean Streak rotor for the 17" rear conversion
« Reply #2 on: January 25, 2013, 10:13:06 am »
Agree with GFinCA it is hard on the tool, On a lathe all is ok until you get to the holes. The tool is cutting what is called an interuppted cut which is hard on the tool. I was lucky and a friend of mine in the toolroom found out what I was doing and cut it for me on a Wire EDM machine, cuts like butter with the right machinery. Lathe or CNC Mill is doable but will take many cuts.
Southern Connecticut.
97 C10,ZRX Front, Meanstreak rim

Offline Dave Scott

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Re: Mean Streak rotor for the 17" rear conversion
« Reply #3 on: January 25, 2013, 01:08:15 pm »
as an alternative, if you can find a Nomad front rotor, it should bolt right on and is already a 280mm.

Offline Bergmen

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Re: Mean Streak rotor for the 17" rear conversion
« Reply #4 on: January 25, 2013, 03:52:51 pm »
Another alternative for machining would be to have it done on a Bridgeport with a rotary table. A bit of set-up but milling would not risk damage to the tool.

Dan
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