 Engine rebuild, a few questions |
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| stugray |
 Aug 27 2012, 12:00 AM
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#21
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Advanced Member  Group: Members Posts: 3,825 Joined: 17-September 09 From: Longmont, CO Member No.: 10,819 Region Association: None  |
Thanks for the tips.
I will target 50cc if I can get there. I will put the head on and see how much room I have before the head hits the cyl fins. Next question: The standard (ace hardware) 10mm grade 8 washers are not quite as big OD as the stock washers. Is that OK? The stock part is: 900 025 008 02 However I cannot find that exact part anywhere. Can I use the slightly smaller washers or are the larger ones critical? Stu |
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| Valy |
Aug 27 2012, 10:50 AM
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#22
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Senior Member Group: Members Posts: 1,677 Joined: 6-April 10 From: Sunnyvale, CA Member No.: 11,573 Region Association: Northern California |
You need big washers to spread the load.
I got mine at Home Depot. Look harder (IMG:style_emoticons/default/smile.gif) |
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| ChrisFoley |
Aug 27 2012, 11:25 AM
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#23
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I am Tangerine Racing Group: Members Posts: 8,019 Joined: 29-January 03 From: Bolton, CT Member No.: 209 Region Association: None 
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Stu,
A tight deck is much better for efficient combustion. It makes no sense to cut the heads to an excessive CR and then shim up to attain the desired CR. Calculate the total combustion chamber volume with a .010" shim and cut them as close to that as you can. The way I determined how deep to cut recently, when I was adjusting a head to match another one, was to transfer the shape of the cyl. head chamber onto graph paper and count the squares inside the shape. It doesn't take that long. This method yields a very good estimate of volume removed per given cut depth. |
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| Dave_Darling |
Aug 27 2012, 03:56 PM
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#24
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914 Idiot Group: Members Posts: 15,328 Joined: 9-January 03 From: Silicon Valley / Kailua-Kona Member No.: 121 Region Association: Northern California
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Are the 2.0 heads the ones where it is easy to break through into one of the exhaust stud bores? I know that there is one Type IV head that gets very very thin near the exhaust stud when you fly-cut it a bunch.
--DD |
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