what would cause this?
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From: Near Frankenmuth, MI
I was curious to know for sure if the break-in process and set-up (timing) might have had something to do with it too?
I have mine offset 2 degrees and can really tell a difference between running when it's first warmed up, and when it's well heated up after being on the road for a short while.
Since the overhaul it's been a whole different motor and runs like brand new with just the top end rebuilt. The change to 9.6:1 from 8.5:1, and the .30 over can really be felt in acceleration. And the smoothness of the rebuild running is noticed at cruising speeds. Also the clatter is gone. Can't believe how worn the old top end was at 61K.
Once again, best wishes taking care of your situation.
Dirt don't hurt
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From: Haslet Texas
When you say offset are you talking about advanced or retarded?
Outstanding HDF Member
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From: Near Frankenmuth, MI
Retarded.
I think this is why I feel a difference in running when warmed up, and later when really heated up. When heated up it responds with excitement. When warmed up it has a slight hesitation when giving it WOT.
But I admit my old butterfly carb need replacing, and to get optimum performance a set of better pipes is needed too. Soon I hope!!
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From: Farmington ,MS
Correct answer...KB pistons come with a warning about this.
Last edited by Tom84FXST; May 23, 2014 at 10:17 PM.
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From: South Carolina
For those folks that may not know the difference between pre igniton (quick engine killer) and detonation (what we hear as pinging).
Here`s a link to a good description.
http://www.streetrodstuff.com/Articl...ne/Detonation/
Here`s a link to a good description.
http://www.streetrodstuff.com/Articl...ne/Detonation/
Last edited by Dan89FLSTC; May 25, 2014 at 07:20 AM.
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From: Lincoln ne
Well I guess the extra ring gap (or lack there of) would be the main contributor to my problem! What I don't understand is why the pistons didn't come with that handy dandy sheet. If I would have known that I wouldn't be dropping another $600. And only JE makes pistons that are 3.518 and 10.5:1 compression. It doesn't make sense that it took that long to do it though. My break in method was that of mototune, I wasn't easy on it... and why wouldn't the front cylinder have done the same thing? Oh well the great mystery I guess...
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From: la la land jerzey
Well I guess the extra ring gap (or lack there of) would be the main contributor to my problem! What I don't understand is why the pistons didn't come with that handy dandy sheet. If I would have known that I wouldn't be dropping another $600. And only JE makes pistons that are 3.518 and 10.5:1 compression. It doesn't make sense that it took that long to do it though. My break in method was that of mototune, I wasn't easy on it... and why wouldn't the front cylinder have done the same thing? Oh well the great mystery I guess...
the JEs want .0035 or even a little more depends on what your doing and the bikes weight and other stuff ask your guy what he thinks AND they are not quiet they do get better hot
in my shop we would not want that much compression in that over size .030 piston as evos are thin to begin with -- just my take
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From: Near Frankenmuth, MI
Interesting this came up again. I checked my box and the instructions were in it. Turns out they are .20. I thought I was told they were .30.
And in talking with their tech service I was informed the statement about a 2 to 4 degree retard was only to keep people from advancing the timing and causing critical issues. I was told this was the idea of a company tech many, many years ago.
I was told, and as is in the instructions "FINAL TIMING MAY VARY WITH YOUR APPLICATION". It has more to do with adjusting to where the motor runs the best and dyno testing would be the best to have it run precisley at it's peak and not cause damage.
I now know this wasn't the issue with the piston ring situation in the photos on this thread.
And in talking with their tech service I was informed the statement about a 2 to 4 degree retard was only to keep people from advancing the timing and causing critical issues. I was told this was the idea of a company tech many, many years ago.
I was told, and as is in the instructions "FINAL TIMING MAY VARY WITH YOUR APPLICATION". It has more to do with adjusting to where the motor runs the best and dyno testing would be the best to have it run precisley at it's peak and not cause damage.
I now know this wasn't the issue with the piston ring situation in the photos on this thread.