Author Topic: Cobra motor disassembly and rebuild  (Read 107659 times)

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Offline Bill/BentON Racing

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Re: Cobra motor disassembly and rebuild
« Reply #150 on: January 09, 2016, 03:49:53 PM »
Same caliper sold for $297.50! Getting there. All helicoils done! Yeah Time for its bath!!
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1993 HRC RS125 | 1984 NS400R | 1974 Honda CB750/836cc (Calendar Girl) | 1972 CB 500/550 Yoshi Kitted 590cc | 1965 Honda CB450 Black Bomber | 1972 Suzuki T350 | 1973 88cc | Z50/Falcons Pit Bike | 1967 CA100| 1974 CB350 (400F motor)...and more.
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Offline Bill/BentON Racing

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Re: Cobra motor disassembly and rebuild
« Reply #151 on: January 09, 2016, 04:15:09 PM »
Got to wash all this away!
BentON Racing Website
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Over 35 years of experience working on vintage motorcycles, with a speciality in Honda SOHC/4 with a focus on the CB750 and other models as well from 1966 - 1985.
______________________________________
1993 HRC RS125 | 1984 NS400R | 1974 Honda CB750/836cc (Calendar Girl) | 1972 CB 500/550 Yoshi Kitted 590cc | 1965 Honda CB450 Black Bomber | 1972 Suzuki T350 | 1973 88cc | Z50/Falcons Pit Bike | 1967 CA100| 1974 CB350 (400F motor)...and more.
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Offline Bill/BentON Racing

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Re: Cobra motor disassembly and rebuild
« Reply #152 on: January 09, 2016, 05:52:05 PM »
Getting there.
BentON Racing Website
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Over 35 years of experience working on vintage motorcycles, with a speciality in Honda SOHC/4 with a focus on the CB750 and other models as well from 1966 - 1985.
______________________________________
1993 HRC RS125 | 1984 NS400R | 1974 Honda CB750/836cc (Calendar Girl) | 1972 CB 500/550 Yoshi Kitted 590cc | 1965 Honda CB450 Black Bomber | 1972 Suzuki T350 | 1973 88cc | Z50/Falcons Pit Bike | 1967 CA100| 1974 CB350 (400F motor)...and more.
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Offline Jerry Rxman Griffin aka MuthaF'er

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Re: Cobra motor disassembly and rebuild
« Reply #153 on: January 09, 2016, 06:30:20 PM »
 ;)
As of today 3/13/2012 my original owner 75 CB750F has made it through 3 wives, er EX-wives. Free at last.  ;-)

Offline gschuld

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Re: Cobra motor disassembly and rebuild
« Reply #154 on: January 09, 2016, 08:20:20 PM »
Purdy 8)

Offline Bill/BentON Racing

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Re: Cobra motor disassembly and rebuild
« Reply #155 on: January 09, 2016, 09:21:36 PM »
Finished, well 98%!
BentON Racing Website
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Over 35 years of experience working on vintage motorcycles, with a speciality in Honda SOHC/4 with a focus on the CB750 and other models as well from 1966 - 1985.
______________________________________
1993 HRC RS125 | 1984 NS400R | 1974 Honda CB750/836cc (Calendar Girl) | 1972 CB 500/550 Yoshi Kitted 590cc | 1965 Honda CB450 Black Bomber | 1972 Suzuki T350 | 1973 88cc | Z50/Falcons Pit Bike | 1967 CA100| 1974 CB350 (400F motor)...and more.
______________________________________
See our latest build 'Captain Marvel' CLICK HERE

Offline Bill/BentON Racing

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Re: Cobra motor disassembly and rebuild
« Reply #156 on: January 09, 2016, 09:26:35 PM »
Too save this head....29 of 30 6mm bolt holes had to be helicoiled! One valve cover bolt was fine, so I left it cause I could !!! 29 f'in ones! But I wanted to be like Mike Rieck. ..so I did it, anything to save 40 year old RC parts!  ;D, Bill
BentON Racing Website
OEM Parts | Service | Custom Builds
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Over 35 years of experience working on vintage motorcycles, with a speciality in Honda SOHC/4 with a focus on the CB750 and other models as well from 1966 - 1985.
______________________________________
1993 HRC RS125 | 1984 NS400R | 1974 Honda CB750/836cc (Calendar Girl) | 1972 CB 500/550 Yoshi Kitted 590cc | 1965 Honda CB450 Black Bomber | 1972 Suzuki T350 | 1973 88cc | Z50/Falcons Pit Bike | 1967 CA100| 1974 CB350 (400F motor)...and more.
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See our latest build 'Captain Marvel' CLICK HERE

Offline NalleyRacing

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Re: Cobra motor disassembly and rebuild
« Reply #157 on: January 09, 2016, 09:57:35 PM »
I smell a 10 second pass a'cookin  ;D

Offline Big Jay

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Re: Cobra motor disassembly and rebuild
« Reply #158 on: January 09, 2016, 11:08:18 PM »
Bill, send me the crank and I will balance it.

Offline Bill/BentON Racing

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Re: Cobra motor disassembly and rebuild
« Reply #159 on: January 10, 2016, 04:59:09 AM »
Deal brother.  I'll box it up and shoot it out tomorrow, thanks Jay, I need all the help I can get. K. ;D, Bill
BentON Racing Website
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Over 35 years of experience working on vintage motorcycles, with a speciality in Honda SOHC/4 with a focus on the CB750 and other models as well from 1966 - 1985.
______________________________________
1993 HRC RS125 | 1984 NS400R | 1974 Honda CB750/836cc (Calendar Girl) | 1972 CB 500/550 Yoshi Kitted 590cc | 1965 Honda CB450 Black Bomber | 1972 Suzuki T350 | 1973 88cc | Z50/Falcons Pit Bike | 1967 CA100| 1974 CB350 (400F motor)...and more.
______________________________________
See our latest build 'Captain Marvel' CLICK HERE

Offline Bill/BentON Racing

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Re: Cobra motor disassembly and rebuild
« Reply #160 on: January 10, 2016, 01:19:24 PM »
Anyone wondering crank weighs 19 lbs.
BentON Racing Website
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Over 35 years of experience working on vintage motorcycles, with a speciality in Honda SOHC/4 with a focus on the CB750 and other models as well from 1966 - 1985.
______________________________________
1993 HRC RS125 | 1984 NS400R | 1974 Honda CB750/836cc (Calendar Girl) | 1972 CB 500/550 Yoshi Kitted 590cc | 1965 Honda CB450 Black Bomber | 1972 Suzuki T350 | 1973 88cc | Z50/Falcons Pit Bike | 1967 CA100| 1974 CB350 (400F motor)...and more.
______________________________________
See our latest build 'Captain Marvel' CLICK HERE

Offline Sam Green Racing

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Re: Cobra motor disassembly and rebuild
« Reply #161 on: January 10, 2016, 04:07:44 PM »
I'd give my right arm to be helping you Billy  :'(
C95 sprint bike.
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Offline Retro Rocket

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Re: Cobra motor disassembly and rebuild
« Reply #162 on: January 10, 2016, 04:11:41 PM »
I'd give my right arm to be helping you Billy  :'(

I think I can arrange shipping for that Sam.... ;D ;)

Nice work Bill... ;)
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If You can't fix it with a hammer, You've got an electrical problem.

Offline Sam Green Racing

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Re: Cobra motor disassembly and rebuild
« Reply #163 on: January 10, 2016, 04:14:53 PM »
I'll bet you can, hahaha
C95 sprint bike.
CB95 hybrid race bike
CB95 race bike
CB92
RS 175. sprint/land speed bike
JMR Racing CB750A street ET drag bike

Offline Retro Rocket

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Re: Cobra motor disassembly and rebuild
« Reply #164 on: January 10, 2016, 04:19:43 PM »
 ;D
750 K2 1000cc
750 F1 970cc
750 Bitsa 900cc
If You can't fix it with a hammer, You've got an electrical problem.

Offline Sam Green Racing

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Re: Cobra motor disassembly and rebuild
« Reply #165 on: January 10, 2016, 05:13:27 PM »
 ;D ;D ;D ;D ;D
C95 sprint bike.
CB95 hybrid race bike
CB95 race bike
CB92
RS 175. sprint/land speed bike
JMR Racing CB750A street ET drag bike

Offline Bill/BentON Racing

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Re: Cobra motor disassembly and rebuild
« Reply #166 on: January 10, 2016, 05:24:58 PM »
Man , so much in the works for 2016!
BentON Racing Website
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Over 35 years of experience working on vintage motorcycles, with a speciality in Honda SOHC/4 with a focus on the CB750 and other models as well from 1966 - 1985.
______________________________________
1993 HRC RS125 | 1984 NS400R | 1974 Honda CB750/836cc (Calendar Girl) | 1972 CB 500/550 Yoshi Kitted 590cc | 1965 Honda CB450 Black Bomber | 1972 Suzuki T350 | 1973 88cc | Z50/Falcons Pit Bike | 1967 CA100| 1974 CB350 (400F motor)...and more.
______________________________________
See our latest build 'Captain Marvel' CLICK HERE

Offline Jerry Rxman Griffin aka MuthaF'er

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Re: Cobra motor disassembly and rebuild
« Reply #167 on: January 10, 2016, 06:46:23 PM »
I'll bet you can, hahaha

Yeah but it has to be attached to the rest of you Sam. Gotta get you back somehow.
As of today 3/13/2012 my original owner 75 CB750F has made it through 3 wives, er EX-wives. Free at last.  ;-)

Offline 754

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Re: Cobra motor disassembly and rebuild
« Reply #168 on: January 10, 2016, 06:49:23 PM »
Let me know if you need a steering stem for the Ceriani, have to make one for mine and maybe some Betor trees as well ..weigh that Pm caliper, i think they were like 14 oz.  We ran 4 of them on a chopper, the guy said it stopped better than expected..
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Offline Bill/BentON Racing

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Re: Cobra motor disassembly and rebuild
« Reply #169 on: January 11, 2016, 04:51:46 AM »
Frank, will do. It's very light for sure,  thanks, Bill
BentON Racing Website
OEM Parts | Service | Custom Builds
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Over 35 years of experience working on vintage motorcycles, with a speciality in Honda SOHC/4 with a focus on the CB750 and other models as well from 1966 - 1985.
______________________________________
1993 HRC RS125 | 1984 NS400R | 1974 Honda CB750/836cc (Calendar Girl) | 1972 CB 500/550 Yoshi Kitted 590cc | 1965 Honda CB450 Black Bomber | 1972 Suzuki T350 | 1973 88cc | Z50/Falcons Pit Bike | 1967 CA100| 1974 CB350 (400F motor)...and more.
______________________________________
See our latest build 'Captain Marvel' CLICK HERE

Offline scottly

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Re: Cobra motor disassembly and rebuild
« Reply #170 on: January 11, 2016, 06:17:36 PM »
Anyone wondering crank weighs 19 lbs.
How does that compare to a stock crank, Bill? Remember, energy is stored in the rotating mass of the crank, and this stored energy is what launches you off the line when you let out the clutch at 6000 RPM. Weight in the right place can sometimes be your friend. ;)
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Offline TurboD

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Re: Cobra motor disassembly and rebuild
« Reply #171 on: January 11, 2016, 06:27:24 PM »
I agree Scottly, depending on a racers clutch hand a lightened crank may not be your friend.

Offline dragracer

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Re: Cobra motor disassembly and rebuild
« Reply #172 on: January 11, 2016, 06:52:46 PM »
I agree Scottly, depending on a racers clutch hand a lightened crank may not be your friend.

Not a fan of lightened cranks in dragracing. Need that rotating weight off the line as TurboD mentioned. Light weight rods and pistons are okay, light bikes okay, light riders even better- light cranks no bueno.

Offline Bill/BentON Racing

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Re: Cobra motor disassembly and rebuild
« Reply #173 on: January 11, 2016, 08:51:55 PM »
22lbs stock. That's why I run my lightened rotor some. Helps launch. Stroker cranks I just want balanced on a 750, they ate weak already once stroked. 900F I'll probably lighten some. Well, why don't you add a few pounds then and balance. Cause it going slow it down maybe?  A fine balance no doubt!
Grandma will launch it! ;D, Bill 
BentON Racing Website
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Over 35 years of experience working on vintage motorcycles, with a speciality in Honda SOHC/4 with a focus on the CB750 and other models as well from 1966 - 1985.
______________________________________
1993 HRC RS125 | 1984 NS400R | 1974 Honda CB750/836cc (Calendar Girl) | 1972 CB 500/550 Yoshi Kitted 590cc | 1965 Honda CB450 Black Bomber | 1972 Suzuki T350 | 1973 88cc | Z50/Falcons Pit Bike | 1967 CA100| 1974 CB350 (400F motor)...and more.
______________________________________
See our latest build 'Captain Marvel' CLICK HERE

Offline dragracer

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Re: Cobra motor disassembly and rebuild
« Reply #174 on: January 12, 2016, 06:23:30 AM »
Wise move to balance it Bill. No way would I ever consider running a engine with thrown together parts without balancing the rotating assembly. I learned that years ago from a big block Chevy engine I had in a 1970 Nova SS, 396 with a 4 speed. Spend the money now, or you will be spending it later.