Author Topic: different piston clearances for outside pistons?  (Read 1117 times)

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Offline Elan

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different piston clearances for outside pistons?
« on: February 04, 2011, 11:00:08 AM »
Getting my cylinders bored for an 836 build. I told the machinist .0008 to .0010"  clearance. He just replied with this:

"Got it.

I will set them up at .0010” for the inside cylinders and .0008” for the outside."


So I asked why different sizes and got this:



"On an air cooled motor, the inside cylinders always run  hotter.

I have bored about 1000 air cooled fours and I always do it that way."


Is he gonna f up my motor?

 
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Offline ekpent

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Re: different piston clearances for outside pistons?
« Reply #1 on: February 04, 2011, 11:07:29 AM »
Better tell him to hold up for a second till Hondaman.Mriek or somebody comes along.Don't think I would feel comfortable with that.

Offline Mark M

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Re: different piston clearances for outside pistons?
« Reply #2 on: February 04, 2011, 11:14:11 AM »
You got yourself a switch on machinist, many wouldn't bother with that kind of detail to the job ;D
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Offline Elan

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Re: different piston clearances for outside pistons?
« Reply #3 on: February 04, 2011, 11:22:09 AM »
Im thinking it can't hurt considering its still within spec regardless....
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Offline ekpent

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Re: different piston clearances for outside pistons?
« Reply #4 on: February 04, 2011, 11:36:08 AM »
Sounds like he has done a lot of them thats for sure.Guess if there was a problem he would have found it out.I know the multi cylinder two stroke sometimes had problems with the inner slugs..I will watch and learn.

Offline MRieck

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Re: different piston clearances for outside pistons?
« Reply #5 on: February 04, 2011, 11:46:05 AM »
What kind of pistons. That is to tight for 99% of forged pistons. Where did you get those clearance #'s? MTC's have some much skirt taper they can be run that tight but they don't make an 836 kit as far as I know
« Last Edit: February 04, 2011, 11:48:21 AM by MRieck »
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Offline Elan

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Re: different piston clearances for outside pistons?
« Reply #6 on: February 04, 2011, 11:56:32 AM »
What kind of pistons. That is to tight for 99% of forged pistons. Where did you get those clearance #'s? MTC's have some much skirt taper they can be run that tight but they don't make an 836 kit as far as I know

GOt it from this thread.....
http://forums.sohc4.net/index.php?topic=68776.0

What clearance are you thinking? They are cast, not forged

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« Last Edit: February 04, 2011, 11:58:51 AM by Elan »
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