Author Topic: Cobra motor disassembly and rebuild  (Read 107455 times)

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Offline dragracer

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Re: Cobra motor disassembly and rebuild
« Reply #775 on: January 17, 2017, 10:14:10 PM »
Had one on my small tire Kawasaki dragbike for years. I found out how well it works one day when I raised my head up from behind the fairing just as I crossed the traps on a 1/4 pass. At 145mph, the wind turned my helmet around on my head and I was temporarily in total darkness. Not cool at all. Took all the composure I had to maintain a straight line with one hand as,I pulled my helmet back in place with the other. Streamlining makes a difference along with a tight helmet strap and a properly fitted helmet.

Offline dragracer

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Re: Cobra motor disassembly and rebuild
« Reply #776 on: January 17, 2017, 10:28:45 PM »
I think I bought mine from Chaparral about 20 years ago. They still stock the with windshield for around $60.

Offline PeWe

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Re: Cobra motor disassembly and rebuild
« Reply #777 on: January 19, 2017, 10:02:14 AM »
Billy,

Go big or go home right ;)

How about an Assassin style road race full fairing...

George

Nice photo George! A CB750, right?
That's how to ride a bike!!
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 gschuld

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Re: Cobra motor disassembly and rebuild
« Reply #778 on: January 19, 2017, 11:37:24 AM »
Sure is, Russ Collins before he became "famous".  1971 or 1972, single engine, Ralph Muldoon aluminum dragster chassis.   Pepco blower, nitro methane injected.

Good stuff.

Offline PeWe

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Re: Cobra motor disassembly and rebuild
« Reply #779 on: January 20, 2017, 03:30:43 AM »
It must be old videos somewhere with the sound of those hot CB750's?

That flaming photo would fit a bottle/jar with hot chili. Trinidad Scorpion,  Bhut Jolokia (Ghost pepper) or similar tasty stuff!
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 dragracer

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Re: Cobra motor disassembly and rebuild
« Reply #780 on: January 20, 2017, 05:37:24 AM »
We need that picture of Bill on Purple Rain.

I only have one from my Kaw.

Offline MRieck

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Re: Cobra motor disassembly and rebuild
« Reply #781 on: January 20, 2017, 01:01:42 PM »
Sure is, Russ Collins before he became "famous".  1971 or 1972, single engine, Ralph Muldoon aluminum dragster chassis.   Pepco blower, nitro methane injected.

Good stuff.
Saw a Muldoon frame drag bike on a dyno last week. ;)
Owner of the "Million Dollar CB"

Offline bwaller

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Re: Cobra motor disassembly and rebuild
« Reply #782 on: January 20, 2017, 02:08:52 PM »
 Saw a Muldoon frame drag bike on a dyno last week. ;)



Ahhh, anybody we know?

Offline gschuld

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Re: Cobra motor disassembly and rebuild
« Reply #783 on: January 20, 2017, 02:51:08 PM »
Sure is, Russ Collins before he became "famous".  1971 or 1972, single engine, Ralph Muldoon aluminum dragster chassis.   Pepco blower, nitro methane injected.

Good stuff.
Saw a Muldoon frame drag bike on a dyno last week. ;)

Not something you see every day... :o  Very cool

George

Offline MRieck

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Re: Cobra motor disassembly and rebuild
« Reply #784 on: January 21, 2017, 07:08:40 AM »
Saw a Muldoon frame drag bike on a dyno last week. ;)



Ahhh, anybody we know?
He's not on the forum Brent. Very hot 836 engine.....should work very well. :D
Owner of the "Million Dollar CB"

Offline MRieck

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Re: Cobra motor disassembly and rebuild
« Reply #785 on: January 21, 2017, 03:26:27 PM »
Saw a Muldoon frame drag bike on a dyno last week. ;)



Ahhh, anybody we know?
He's not on the forum Brent. Very hot 836 engine.....should work very well. :D
Hopefully he gets down to Valdosta. He's an older fella getting back into racing. Super nice guy. It should fly pretty good......maybe 9's with some practice or a seasoned rider. I'll have to go up to New Hampshire and see it run. ;)
Owner of the "Million Dollar CB"

Offline Bill/BentON Racing

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Re: Cobra motor disassembly and rebuild
« Reply #786 on: January 22, 2017, 05:09:36 PM »
Here's some excellent hi performance duct tape! Lol, 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 #787 on: January 22, 2017, 06:07:46 PM »
Hey Bill, thanks for coming to the meeting yesterday. We at least got Mike to consider reducing the number of races. Not sure what else productive was accomplished. Nevertheless, we'll make as many as possible.

 And I appreciate you bringing the valve cover. It'll probably be my only piece of bling on the engine, thanks to you.

Offline Jerry Rxman Griffin aka MuthaF'er

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Re: Cobra motor disassembly and rebuild
« Reply #788 on: January 22, 2017, 06:39:37 PM »
Here's some excellent hi performance duct tape! Lol, Bill

Send him some Falcons place mats......  ;)
As of today 3/13/2012 my original owner 75 CB750F has made it through 3 wives, er EX-wives. Free at last.  ;-)

Offline Sam Green Racing

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Re: Cobra motor disassembly and rebuild
« Reply #789 on: January 23, 2017, 02:13:48 AM »
We need that picture of Bill on Purple Rain.

I only have one from my Kaw.

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 Medyo Bastos

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Re: Cobra motor disassembly and rebuild
« Reply #790 on: January 26, 2017, 03:59:44 PM »
Sure is, Russ Collins before he became "famous".  1971 or 1972, single engine, Ralph Muldoon aluminum dragster chassis.   Pepco blower, nitro methane injected.

Good stuff.
Saw a Muldoon frame drag bike on a dyno last week. ;)

I'd like to have a Muldoon frame myself


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Offline Bill/BentON Racing

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Re: Cobra motor disassembly and rebuild
« Reply #791 on: January 29, 2017, 07:59:32 PM »
Well, not sure who made it yet, Kosman looking kinda,  I know I like it, the work looks professional.  Looks promising.  Gotta get busy,  Bill
BentON Racing Website
OEM Parts | Service | Custom Builds
BentON Racing Facebook
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 Bill/BentON Racing

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Re: Cobra motor disassembly and rebuild
« Reply #792 on: January 31, 2017, 08:56:37 PM »
Here you go. Single digit bike, Yippee Kai Yeah! Lol,  I'm a certified Honda 750 nut! ;D, Bill
BentON Racing Website
OEM Parts | Service | Custom Builds
BentON Racing Facebook
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 #793 on: January 31, 2017, 09:36:17 PM »
Something tells me we'll see a single digit Honda going down the track in 2017.

Offline kmb69

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Re: Cobra motor disassembly and rebuild
« Reply #794 on: February 01, 2017, 07:50:04 AM »
Something tells me we'll see a single digit Honda going down the track in 2017.


Pretty sure you are correct!  ;)

And.....it won't require a blower or N2O!!!!!  :o  ;)  8)

Offline dragracer

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Re: Cobra motor disassembly and rebuild
« Reply #795 on: February 01, 2017, 10:24:25 AM »
Something tells me we'll see a single digit Honda going down the track in 2017.


Pretty sure you are correct!  ;)

And.....it won't require a blower or N2O!!!!!  :o  ;)  8)


Great to know someone is shooting for the nine second zone, N/A. My pockets are shallow and resources limited for that type package so I won't be attempting that particular record. I'm sticking with a poor man's method of making power. 😁

Offline Bill/BentON Racing

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Re: Cobra motor disassembly and rebuild
« Reply #796 on: February 20, 2017, 06:55:50 PM »
I wish mine had lasted this long! Lol
BentON Racing Website
OEM Parts | Service | Custom Builds
BentON Racing Facebook
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 #797 on: July 02, 2017, 07:35:09 AM »
Well,  after 6 weeks,  I can finally wrench again. So back at it, got to get ready for Galot, 1/8 mile! Gotta rebuild F brake m/cylinder and maybe caliper also. Oil pump needs Elan's kit also. Check fuel delivery and time to crank Patches again!
BentON Racing Website
OEM Parts | Service | Custom Builds
BentON Racing Facebook
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 #798 on: July 02, 2017, 08:31:43 AM »
Great news Bill. Get at it  ;D
As of today 3/13/2012 my original owner 75 CB750F has made it through 3 wives, er EX-wives. Free at last.  ;-)

Offline dragracer

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Re: Cobra motor disassembly and rebuild
« Reply #799 on: July 02, 2017, 08:53:50 AM »
Sounds good Bill. I know you've been anxious to get the bike repairs done so you could do some testing. The Galot race is approaching fast for us. Take care of the hand.