Author Topic: RC cam?  (Read 1972 times)

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Offline Don R

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RC cam?
« on: February 11, 2010, 05:09:20 PM »
My brother brought this cam over #RC315  and  85 59 90K stamped on the end. How big is it? 
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Offline Don R

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Re: RC cam?
« Reply #1 on: February 11, 2010, 07:55:50 PM »
Never mind,I searched earlier and came up empty, Tried again and got it all. I didn't realize this was the same one here a few days ago. I really expected this one to be more radical. He got it with a 1000 race engine a long time ago.
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.

Offline 754

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Re: RC cam?
« Reply #2 on: February 11, 2010, 09:37:04 PM »
Int 55  85 deg

Ex 85  55deg

.375 lift on Int & Ex

Running clearance .012

#315 Hot Street Strong Torque curve from ground up--comes on low and never quits. This one makes lots of horsepower. Very good for heavy street ans altered bikes. Oor favorite in street class Has twisted us to many national records. Very streetable. Fair idle--quiet.

Quoted from an RC catalog..
..........................................................

 IF by chance you do not want to run it, I am ready to buy.....

 PM me..
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73 836cc.. Green, had it for 3 decades!!
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Offline Don R

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Re: RC cam?
« Reply #3 on: February 12, 2010, 08:54:19 AM »
Thanks, for the added info. If he wanted to sell it I would be first in line. My brothers hoarding of 750 parts have made it possible for me to re-build my 70 with relative ease. Little things like faded handlebar controls with cut wires that most people would toss, I have taken apart and made one good part from several. Like a right switch with a black kill knob. It's hard to toss even the junkest part after using boxes of rusty junk to make realy nice looking parts that work.
  The 1000plus engine he sold back to the original owner is one he wishes he had kept now. It was a 1000 with a stroker crank. It had external oil lines. We couldn't find rings for it and didn't have any idea there was a site like this where we could get information. Brings a tear to my eye, the guy that built it owned the local Honda shop and wanted the fastest one around. It was.
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 Jerry Rxman Griffin aka MuthaF'er

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Re: RC cam?
« Reply #4 on: February 12, 2010, 09:36:09 AM »
Frank, Don,

If you want a new 315 just buy one from Buzz at Dynoman.
As of today 3/13/2012 my original owner 75 CB750F has made it through 3 wives, er EX-wives. Free at last.  ;-)

Offline Don R

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Re: RC cam?
« Reply #5 on: February 12, 2010, 09:49:52 AM »
Dynoman.net   DP315, needs the springs of course, how about the ti retainers?
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 754

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Re: RC cam?
« Reply #6 on: February 12, 2010, 09:51:22 AM »
I believe I looked at those.. different specs.. ???

 Sounds like the same , only different.. ???

 I always wonder, why they cant sell on their own merits.

 I think the 315 is fairly close to one of the Megas..

 I will say this, with Webers, stock ports/valves, but with good valvejob, and 10.5 836 kit, I am really sierprised at how much midrange I was getting out of a 4 cylinder.. really nice on the street.. I would like to try a 327 RC, but I fear it may be a tad peaky..

 Still looking for another 315 or 327 though.. in good shape.
Maker of the WELDLESS 750 Frame Kit
dodogas99@gmail.com
Kelowna B.C.       Canada

My next bike will be a ..ANFOB.....

It's All part of the ADVENTURE...

73 836cc.. Green, had it for 3 decades!!
Lost quite a few CB 750's along the way

Offline MRieck

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Re: RC cam?
« Reply #7 on: February 12, 2010, 10:13:49 AM »
I believe I looked at those.. different specs.. ???

 Sounds like the same , only different.. ???

 I always wonder, why they cant sell on their own merits.

I think the 315 is fairly close to one of the Megas..

 I will say this, with Webers, stock ports/valves, but with good valvejob, and 10.5 836 kit, I am really sierprised at how much midrange I was getting out of a 4 cylinder.. really nice on the street.. I would like to try a 327 RC, but I fear it may be a tad peaky..

 Still looking for another 315 or 327 though.. in good shape.
Yes. It's kinda in between the 125-65 and 125-75
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Offline NitroHunter

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Re: RC cam?
« Reply #8 on: February 12, 2010, 10:36:34 AM »
The 256 duration @ .050" lift (as shown on the cam card) will give you a better comparison to other cams.
With decent compression this is a great cam, plenty of arm-stretching from 5k-redline+  ;D

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Offline NitroHunter

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Re: RC cam?
« Reply #9 on: February 12, 2010, 11:21:28 AM »
And with a little valve seat work they fit in F-2 heads...
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Offline Don R

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Re: RC cam?
« Reply #10 on: February 12, 2010, 10:15:45 PM »
Thanks, Nitro.  I copied the cam card for him. He appreciates it. Gotta get him on a new computer so he can get back on here.
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 City Boy

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Re: RC cam?
« Reply #11 on: February 12, 2010, 10:38:24 PM »
Hi gang.It would appear that RC changed the specs on the #315 at some point.The sheet that came with mine reads:Intake opens 12BTDC,Exhaust opens 42BDC,Intake closes 42 afterBDC,Exhaust closes 12 after TDC.Lift 358 IN. and EX.Duration 234 IN. and EX.Interesting!  Rock On
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Offline MRieck

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Re: RC cam?
« Reply #12 on: February 13, 2010, 06:37:01 AM »
Hi gang.It would appear that RC changed the specs on the #315 at some point.The sheet that came with mine reads:Intake opens 12BTDC,Exhaust opens 42BDC,Intake closes 42 afterBDC,Exhaust closes 12 after TDC.Lift 358 IN. and EX.Duration 234 IN. and EX.Interesting!  Rock On
That is probably because they started listing lift and duration #'s at .050 lift.
Owner of the "Million Dollar CB"

Offline Don R

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Re: RC cam?
« Reply #13 on: February 13, 2010, 07:32:38 AM »
  That would make sense. At some point I know the cam companies tried to standardize the numbers so it was easier to compare cams. Same cam, just different measuring method. There can still be differences in lobe profile even with the same numbers.
  What about retainers? Are the titanium retainers needed? Is there a more affordable alternative? I understand about inertia and mass at high rpm, just wondering.
  What about used rockers on a new cam? I know it's best to have everything new and break the parts in together but at some point with parts getting harder to find compromises will be made. Comp cams also has a new break in oil with the additives restored that most oil is missing now. (end of oil talk) please.
 Just trying to determine the totality of a cam swap and how big a project it really is.
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 NitroHunter

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Re: RC cam?
« Reply #14 on: February 13, 2010, 08:29:56 AM »
Hmmm...
Cam card I posted shows these figures at .050".
Strange indeed.
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Offline 754

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Re: RC cam?
« Reply #15 on: February 13, 2010, 08:35:42 AM »
I have my cam card, will try to post the info later.
Maker of the WELDLESS 750 Frame Kit
dodogas99@gmail.com
Kelowna B.C.       Canada

My next bike will be a ..ANFOB.....

It's All part of the ADVENTURE...

73 836cc.. Green, had it for 3 decades!!
Lost quite a few CB 750's along the way