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Discussion Starter · #1 ·
Has anyone out there experimented with offsetting the ignition timing on the rear cylinder?
I'm looking into new ignition modules and Crane's HI-4TC offers this kind of feature. Just wondering what the application/benefit would be...

Thanks,

Ryan
Pittsburgh, PA

01' Deuce
 

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It's best left alone unless you are looking at competition applications.

The one exception to the rule are Delphi EFI bikes when using the race tuner where you have a relatively accurate means of determining what is happening inside each cylinder.

On a carbureted bike you would need to run the bike on a dyno and even individual EGT, head temperature, and/or fuel curve info on a per cylinder basis will give only so much info.
Then again you can always guess and experiment.
 

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Discussion Starter · #3 ·
Thanks Hippo!
That makes total sense.
That being said, do you have any preference in ignition modules? I like the Dyna and the Crane over Harley because they're adjustable. I plan on building up my bike over time, so I'd like to get an ignition that will work well with relatively stock and a highly modified motor.

thanks!

Ryan
 

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The way the cookie crumbles the overwhelming majority of bikes as in 90%+ we get these days are EFI, maybe they just send them to us. :D

Right now I think the best ignition is the Daytona Twin Tec, as in most flexible and with unique capabilities. Several people sell their privately labeled versions and my guess would be that HQ will give you the best tech support.
 

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The rear cylinder (the weak one) will see 1-3 degrees less advance than the front cylinder under load at high TP. Sometimes you need 4-6 degrees less advance at idle as well to smooth things out. Otherwise they will be basically the same.
This is not something to mess with unless you have resolved all other tunable variables and still have a defined problem.
 
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