Won't start after big bore install

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Mar 10, 2015 | 11:25 AM

#31

prodrag1320

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From: deland,florida

I actually had a bike come in years ago by a DIY guy,bike wouldn't start,couldnt even push start it.he put the heads on with red shop rags in both cylinders (WTF??)

Mar 10, 2015 | 11:43 AM

#32

djl

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From: san antonio

Quote:

Originally Posted by prodrag1320

I actually had a bike come in years ago by a DIY guy,bike wouldn't start,couldnt even push start it.he put the heads on with red shop rags in both cylinders (WTF??)

Very funny; how does one do that?

Mar 10, 2015 | 12:05 PM

#33

Harleycruiser

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Joined: Apr 2012

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From: North Florida

And the winner of name that screw up is .

Quote:

Originally Posted by RKGDCG03

When you say stock push rods are you using the one piece Perfect Fit? Is the base circle of the new cam the same as stock? Your PR could be to long or to short. As has been mentioned check compression and PR placement.

Op, don't think we have all done stuff like that, this why we know what to look for. Mine was exhaust pushrod in intake, and this was after I had done several top ends, things happen, be glad you found the problem.

.

Last edited by Harleycruiser; Mar 10, 2015 at 12:07 PM.

Mar 10, 2015 | 12:45 PM

#34

LowRider68

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Joined: Nov 2014

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From: Sioux Falls, South Dakota

Quote:

Originally Posted by Jameson

Yes I reused the stock pushrods. Should scoop up some adjustables for when I tear this thing back apart?

Don't forget to give us an update. I will be done with my 107" FuelMoto build this coming weekend. I only have 2 pushrods to install, throttle body, tank and exhaust. Not to mention a whole bunch of non-performance mods to add.

The worst part of the build was the damn adjustable pushrods, well, the first one anyways. I'm just nervous about not having the cam in the TDC. But, fuelmoto has been awesome!

Mar 10, 2015 | 01:57 PM

#35

djl

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From: san antonio

Quote:

Originally Posted by Harleycruiser

be glad you found the problem.

What did I miss? Haven't seen the OP post the problem had been solved.

Mar 10, 2015 | 02:02 PM

#36

Harleycruiser

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From: North Florida

Quote:

Originally Posted by Jameson

The cam is not stock it's an S&S 570. I'm picking up adjustables now. I feel like a freaking idiot and it's now been made public lol.

Quote:

Originally Posted by djl

What did I miss? Haven't seen the OP post the problem had been solved.

Stock push rods with a 570 cam.

.

Mar 10, 2015 | 02:40 PM

#37

djl

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From: san antonio

Quote:

Originally Posted by Harleycruiser

Stock push rods with a 570 cam..

Maybe. The 570 base circle is .080" smaller than the OEM base circle which increases the valve train stack up dimension by .040". I am betting that Kirby provided, or recommended a .030" head gasket which would shorten that valve train stack up dimension by .015" which leaves a .025" "gap" in the valve train stack up height. One turn on typical adjustables is .035-.040" and how many of us have adjusted pushrods 1/2 turn to short without introducing starting issues? Noisy for sure but the motor will start and run. We don't know if Kirby decked the heads but if he shaved them at all, that stack up dimensions gets shortened even more. So, while I agree that the OP should be running adjustable pushrods, I am not convinced the pushrods are the problem.

Last edited by djl; Mar 11, 2015 at 11:23 AM.

Mar 10, 2015 | 04:15 PM

#38

target64

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Joined: Jan 2013

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From: Rouses Point, N.Y.

did op ever check the compression like djl suggested way back in the beginning of post ? that's what should have been done after all the basics were checked. way it sounds just cranking and when firing has a hollow sound down the pipes. as op stated. sound like the cams are not timed correct or the cams and crank timing is off also. very common sound when ignition fires with little fuel there and the valves being open has that hollow burp sound. and just cranks.