Author Topic: Piston to head clearance - decking a block?  (Read 9538 times)

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Offline Don R

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Re: Piston to head clearance - decking a block?
« Reply #25 on: June 10, 2013, 08:34:39 PM »
I looks like my build. I cut the head to true it up and get back some compression and opened up the quench band a little. Mine was .008 out of the hole if I remember correctly. I didn't shim the base and didn't get aftermarket springs. I did however float the valves and ding an exhaust, so now I'll be buying springs and retainers and since i'm going bigger on the cam I'll revisit the base gasket issue too.
 I pocket ported the head and it really rips. There is a big thread with lots of specifics hondaman has done a couple of these. They don't all have the piston height issue, maybe the newer kits.
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Offline Don R

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Re: Piston to head clearance - decking a block?
« Reply #26 on: June 10, 2013, 08:37:26 PM »
http://forums.sohc4.net/index.php?topic=89779.225 Look for Hondamans posts starting on page 10 I think
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Offline Big Jay

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Re: Piston to head clearance - decking a block?
« Reply #27 on: June 10, 2013, 11:16:45 PM »
On rockerarm motors it is not necessary to use clay when checking piston to valve. You can just put the cylinder in the overlap phase and put an indicator on the retainer.  Using a makeshift tool you just pull the rocker arm down until the valve touches the piston while taking a direct reading on the indicator.

Offline Nikkisixx

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Re: Piston to head clearance - decking a block?
« Reply #28 on: June 11, 2013, 05:43:04 AM »
That is a bummer Don.  I checked the seat pressure for the stock springs and it was about 40 lbs.  Although I'm just running a stock K0 cam, I got a new set of kibblewhite springs for added insurance.   They seem to put down about 70 lbs of seat pressure. 

Jay - I like the method you describe for piston/valve clearance and plan to use it as a final check when the cam gets degreed in on final assembly. 
It is a proven fact that modifying a SOHC Honda in any way will bring on the apocalypse.

Offline Don R

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Re: Piston to head clearance - decking a block?
« Reply #29 on: June 12, 2013, 07:00:48 PM »
Not so bad. I knew I was bending the rules when I put it together but my race car was sucking up all my bike money. so, I went cheap and paid the price. My local bike shop has exhaust valves in stock. Big jay's got the springs and retainers. What about new keepers?  Are there new ones?
« Last Edit: June 13, 2013, 08:14:05 PM by Don R »
No matter how many times you paint over a shadow, it's still there.
 CEO at the no kill motorcycle shop.
 You don't need a weatherman to know which way the wind blows.

Offline Nikkisixx

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Re: Piston to head clearance - decking a block?
« Reply #30 on: June 13, 2013, 05:30:25 AM »
Not so bad. I knew I was bending the rules when I put it together but my race car was sucking up all my bike money. so, I went cheap and paid the price. My local bike shop has exhaust valves in stock. g jay's got the springs and retainers. What about new keepers?  Are there new ones?

I know Kibblewhite makes 5mm sets of keepers/locks for their conversion kit, but not sure about stock size.  Here is a link for the PDF catalogue:

http://www.kpmivalvetrain.com/pdf/Kibblewhite_2012Catalog_IndComponents.pdf
It is a proven fact that modifying a SOHC Honda in any way will bring on the apocalypse.