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Offline garyhcb750

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Cr 750 conrods
« on: October 14, 2016, 01:19:37 PM »
Anyone know these conrods? I want to use them in a modified CB 750 SOHC motor. Were they made for the original CR 750 motors?
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Offline MRieck

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Re: Cr 750 conrods
« Reply #1 on: October 15, 2016, 06:07:29 AM »
Junk. I have one set and one of the big ends has 3 bearing tang slots. ::)
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Offline Jerry Rxman Griffin aka MuthaF'er

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Re: Cr 750 conrods
« Reply #2 on: October 15, 2016, 11:19:16 AM »
I have 6 of them and can't get a set of 4 with similar enough weights. They are NOT HONDA CR rods.
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Offline Nose736

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Re: Cr 750 conrods
« Reply #3 on: March 25, 2017, 11:57:38 AM »
If your going to use them I would have them re-balanced, Should be able to get them within 1/10th of a gram.
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Offline PeWe

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Re: Cr 750 conrods
« Reply #4 on: March 25, 2017, 02:15:34 PM »
Are these rods old from the 70's or new cheap and poorly made  in china and similar stuff?
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CB750 K6-76  970cc (Earlier 1005cc JMR Billet block on the shelf waiting for a comeback)
CB750 K2-75 Parts assembled to a stock K2

Updates of the CB750 K6 -1976
http://forums.sohc4.net/index.php/topic,180468.msg2092136.html#msg2092136
The billet block build thread
http://forums.sohc4.net/index.php/topic,49438.msg1863571.html#msg1863571
CB750 K2 -1975  build thread
http://forums.sohc4.net/index.php/topic,168243.msg1948381.html#msg1948381
K2 engine build thread. For a complete CB750 -75
http://forums.sohc4.net/index.php/topic,180088.msg2088008.html#msg2088008
Carb jetting, a long story Mikuni TMR32
http://forums.sohc4.net/index.php/topic,179479.msg2104967.html#msg2104967

Offline MRieck

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Re: Cr 750 conrods
« Reply #5 on: March 25, 2017, 03:23:14 PM »
Quote from: PeWe on March 25, 2017, 02:15:34 PM
Are these rods old from the 70's or new cheap and poorly made  in china and similar stuff?
They are garbage. OK if you want to make some kind of internal combustion artwork Per.
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Offline Big Jay

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Re: Cr 750 conrods
« Reply #6 on: March 25, 2017, 11:48:15 PM »
New rod coming by the summer. Stay tuned.
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Offline PeWe

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Re: Cr 750 conrods
« Reply #7 on: March 26, 2017, 03:28:14 AM »
Quote from: MRieck on March 25, 2017, 03:23:14 PM
Quote from: PeWe on March 25, 2017, 02:15:34 PM
Are these rods old from the 70's or new cheap and poorly made  in china and similar stuff?
They are garbage. OK if you want to make some kind of internal combustion artwork Per.
Aha, I saw an ongoing engine build with those in this winter. It is assembled now. 836 with ported head, cam. I hope not weaker than CB750 OEM. If weather will be warm enough for a ride I might visit the guy.
The head was beautifully ported with other inlet spigots.
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CB750 K6-76  970cc (Earlier 1005cc JMR Billet block on the shelf waiting for a comeback)
CB750 K2-75 Parts assembled to a stock K2

Updates of the CB750 K6 -1976
http://forums.sohc4.net/index.php/topic,180468.msg2092136.html#msg2092136
The billet block build thread
http://forums.sohc4.net/index.php/topic,49438.msg1863571.html#msg1863571
CB750 K2 -1975  build thread
http://forums.sohc4.net/index.php/topic,168243.msg1948381.html#msg1948381
K2 engine build thread. For a complete CB750 -75
http://forums.sohc4.net/index.php/topic,180088.msg2088008.html#msg2088008
Carb jetting, a long story Mikuni TMR32
http://forums.sohc4.net/index.php/topic,179479.msg2104967.html#msg2104967

Offline MRieck

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Re: Cr 750 conrods
« Reply #8 on: March 26, 2017, 06:11:39 AM »
Quote from: PeWe on March 26, 2017, 03:28:14 AM
Quote from: MRieck on March 25, 2017, 03:23:14 PM
Quote from: PeWe on March 25, 2017, 02:15:34 PM
Are these rods old from the 70's or new cheap and poorly made  in china and similar stuff?
They are garbage. OK if you want to make some kind of internal combustion artwork Per.
Aha, I saw an ongoing engine build with those in this winter. It is assembled now. 836 with ported head, cam. I hope not weaker than CB750 OEM. If weather will be warm enough for a ride I might visit the guy.
The head was beautifully ported with other inlet spigots.
One can only hope Per. It's all about the bolts....the ones in those rods look crude. Plus the rods themselves are heavy. A reworked OEM rod (polished, balanced, shot peened ) with late style bolts would be a better option IMO.
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Offline PeWe

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Re: Cr 750 conrods
« Reply #9 on: March 26, 2017, 09:39:44 AM »
Quote from: MRieck on March 26, 2017, 06:11:39 AM
Quote from: PeWe on March 26, 2017, 03:28:14 AM
Quote from: MRieck on March 25, 2017, 03:23:14 PM
Quote from: PeWe on March 25, 2017, 02:15:34 PM
Are these rods old from the 70's or new cheap and poorly made  in china and similar stuff?
They are garbage. OK if you want to make some kind of internal combustion artwork Per.
Aha, I saw an ongoing engine build with those in this winter. It is assembled now. 836 with ported head, cam. I hope not weaker than CB750 OEM. If weather will be warm enough for a ride I might visit the guy.
The head was beautifully ported with other inlet spigots.
One can only hope Per. It's all about the bolts....the ones in those rods look crude. Plus the rods themselves are heavy. A reworked OEM rod (polished, balanced, shot peened ) with late style bolts would be a better option IMO.
OK, that sounds bad. He should open the  lower case and replace rod bolts with F2 version then....


Quote from: Big Jay on March 25, 2017, 11:48:15 PM
New rod coming by the summer. Stay tuned.
For power monster  engines or something between OEM and Carillo?
A relatively cheap and durable combo with balanced crank would be fine. If slightly lightened even better ;)
« Last Edit: March 26, 2017, 09:43:21 AM by PeWe »
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CB750 K6-76  970cc (Earlier 1005cc JMR Billet block on the shelf waiting for a comeback)
CB750 K2-75 Parts assembled to a stock K2

Updates of the CB750 K6 -1976
http://forums.sohc4.net/index.php/topic,180468.msg2092136.html#msg2092136
The billet block build thread
http://forums.sohc4.net/index.php/topic,49438.msg1863571.html#msg1863571
CB750 K2 -1975  build thread
http://forums.sohc4.net/index.php/topic,168243.msg1948381.html#msg1948381
K2 engine build thread. For a complete CB750 -75
http://forums.sohc4.net/index.php/topic,180088.msg2088008.html#msg2088008
Carb jetting, a long story Mikuni TMR32
http://forums.sohc4.net/index.php/topic,179479.msg2104967.html#msg2104967

Offline SOHC4 Cafe Racer Fan

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Re: Cr 750 conrods
« Reply #10 on: March 30, 2017, 03:21:18 PM »
Quote from: Big Jay on March 25, 2017, 11:48:15 PM
New rod coming by the summer. Stay tuned.

Any info you can give as to how they compare to Carrillos or Cycle X Super Rods?
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Offline PeWe

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Re: Cr 750 conrods
« Reply #11 on: March 31, 2017, 05:56:47 AM »
Hopefully a good and low cost setup. My APE crank in my K6 is very addictive. Difficult to close the cases in my next K2 project with std crank/rods
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CB750 K6-76  970cc (Earlier 1005cc JMR Billet block on the shelf waiting for a comeback)
CB750 K2-75 Parts assembled to a stock K2

Updates of the CB750 K6 -1976
http://forums.sohc4.net/index.php/topic,180468.msg2092136.html#msg2092136
The billet block build thread
http://forums.sohc4.net/index.php/topic,49438.msg1863571.html#msg1863571
CB750 K2 -1975  build thread
http://forums.sohc4.net/index.php/topic,168243.msg1948381.html#msg1948381
K2 engine build thread. For a complete CB750 -75
http://forums.sohc4.net/index.php/topic,180088.msg2088008.html#msg2088008
Carb jetting, a long story Mikuni TMR32
http://forums.sohc4.net/index.php/topic,179479.msg2104967.html#msg2104967
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