Author Topic: My big bore 750 is stock.  (Read 1334 times)

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Online Don R

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My big bore 750 is stock.
« on: May 07, 2012, 09:50:14 PM »
The PO was pulling everyones leg all those years. He claimed 836, 900 and sometimes 936. Well I should have guessed, I took the head off to determine the bore size for the new head gasket, it appears to be stone stock. I need to dig out the old speedo to remember the miles, don't think it was too many, seems like under 20K.
 It's not the # correct engine for this K0 either but I don't have that one anyway.
 Now the decision is, put it back stock? It seems to run well. Or, I have an 812 engine apart, it was run with a plugged exhaust and is dripping with carbon black, I could maybe if they check out, snag the cylinder and pistons from it, get some rings and gaskets and a hone job. The other choice is a new forged piston 836 kit, but that will kill off the chance of a professional candy paint job $$$$ budget wise.

I've just never been the leave it stock kind of a guy.
« Last Edit: May 07, 2012, 10:10:28 PM by Don R »
No matter how many times you paint over a shadow, it's still there.
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 You don't need a weatherman to know which way the wind blows.

bollingball

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Re: My big bore 750 is stock.
« Reply #1 on: May 08, 2012, 12:02:16 AM »
 It seems to run well.  Then why did you take it apart?
Ken

Online Don R

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Re: My big bore 750 is stock.
« Reply #2 on: May 08, 2012, 07:15:45 AM »
It had a leaky head gasket and is going into a pretty resto-mod bike. I just couldn't do it. I'm glad to get the cocoons out of the head, it should run cooler.
  After sleeping on it I'm over the dissapointment. I think I'll get a stock gasket and pop it back just like it is. I've got everything else already here. It ran so good I was believing there was a big bore kit on it. I guess that's a good thing.
« Last Edit: May 08, 2012, 07:30:26 AM 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 Magilla

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Re: My big bore 750 is stock.
« Reply #3 on: May 08, 2012, 08:39:25 AM »
Don,  are you going to sell it or keep it?  If your selling, do what will bring the most profit.  If your keeping, do what will bring the most joy.
1972   Honda CB350
1972   Yamaha 500
1982   Yamaha 650
1988   Harley Sportster 883
1983   HD FXR Shovelhead
2003   HD Heritage Softail
2006   Victory Vegas Jackpot
1980   Honda CB650
1976   Honda CB750K
1982   Honda CB750
1964   Honda CA95
1982   Kawasaki 550
1974   Honda CL360
1975   Suzuki GT550
1981   Honda CB750
1981   Honda CB750
1970   Norton Commando
1972   Yamaha U7E
1970   BMW R50/5
1976   Honda CB750F

Offline seanbarney41

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Re: My big bore 750 is stock.
« Reply #4 on: May 08, 2012, 02:59:43 PM »
Hey Don, have you found anyone that has 812cc(64mm) oil rings?  I have some nice old ART pistons and cylinder but can't find oil rings.
If it works good, it looks good...

Online Don R

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Re: My big bore 750 is stock.
« Reply #5 on: May 08, 2012, 07:48:06 PM »
Hey Don, have you found anyone that has 812cc(64mm) oil rings?  I have some nice old ART pistons and cylinder but can't find oil rings.
Not yet but it's time to start. I beleive I read the 812 could be made with 350 twin pistons. It's possible those will fit. I'm going to pull the cylinders off the 812 and have a look.
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 seanbarney41

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Re: My big bore 750 is stock.
« Reply #6 on: May 08, 2012, 07:57:13 PM »
Hey Don, have you found anyone that has 812cc(64mm) oil rings?  I have some nice old ART pistons and cylinder but can't find oil rings.
Not yet but it's time to start. I beleive I read the 812 could be made with 350 twin pistons. It's possible those will fit. I'm going to pull the cylinders off the 812 and have a look.
pm me or post here if you find out anything useful, the oil ring I need is one piece and measures the same width and thickness as stockers (.098" thick x .115" wide)  Deves has top and middle rings.
If it works good, it looks good...

Online Don R

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Re: My big bore 750 is stock.
« Reply #7 on: May 08, 2012, 08:07:50 PM »
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 seanbarney41

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Re: My big bore 750 is stock.
« Reply #8 on: May 08, 2012, 08:21:11 PM »
thanks, that may prove helpful
If it works good, it looks good...

Online Don R

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Re: My big bore 750 is stock.
« Reply #9 on: May 08, 2012, 08:47:41 PM »
I posted a pic of my 812 piston also. Let's see what the eXperts say.
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.