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Discussion Starter · #1 ·
I have read many places the TW37 tops out at 9.8:1 , does anyone know what the TW26(G)s optimum compression ratio is ? I saw Bill Bishop using 9.25 on his Stage II . Thanks to all in advance
 

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Different people have different approaches, I tend to run the 37 at 9.5 or 9.6 tops, and the 26 at 9.2 or 9.3 tops, looks like Hammer and Hippo are on the same page.
 

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Discussion Starter · #3 ·
Thanks Hippo , had a wonderful chat with HDwrench yesterday and we decided for my build and riding style the 31G was the best choice.
 

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Based on what one reads on the forum that should put a smile on your face also.
 

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Okay guys, if I run a 26g with 9.3:1 compression on a 95" motor on a carbed bike, can I use the stock ignition module or do I need to to get one that retards the timing say 5* to avoid pinging with 93 octane gas.
Thanks in advance for you replies.
 

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LittleBear said:
Okay guys, if I run a 26g with 9.3:1 compression on a 95" motor on a carbed bike, can I use the stock ignition module or do I need to to get one that retards the timing say 5* to avoid pinging with 93 octane gas.
Thanks in advance for you replies.
it ought to be fine
 

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190lb ccp is optimum. Use a Crane or DTT ign for adjustability and a little more snap. Stock will do and DTT or Crane will do better. USe the compression calculator on the RSR to determine dynamic compression. X.X/1 numbers are not all that meaningful unless you factor in the camshaft timing and altitude.
 
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