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Discussion Starter · #1 ·
Anyone know any details on this Super Hawk with the 450DOHC Top End? Looking for the details, if possible. Any input would be appreciated. ;) Check out the "Dry Clutch also"! :cool: Found some info on adapting the top end from a Suzuki GS400 once but can't find it now, so assistance on finding THAT would also be appreciated. ;) Both conversions would not only give it the DOHC, but would increase the engine size also. :cool:



 

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After some investigation, this one leaves me a little confused.
It has the look of one of the 250/305 RC's, as most other RC's had the dry clutch on the right side.
The open frame suggests to me that it may be a Works racer.
Though the 450-type head is clearly a 450, unlike the heads that are on most RC's, which are only "similar" to a 450 head.

The carbs appear to be very modern vintage, but the front brake looks to be old-school Honda-type.

I'll keep searching, but hopefully someone else may have more insight.
This may be a one-off hybrid that I've simply never run across before.
 

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WOW Bill, that's a cool find if I've ever seen one! Who woulda thunk it??

The ingenuity of motorcyce builders NEVER ceases to AMAZE me!! :shock:

GB :mrgreen:
 

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Discussion Starter · #6 ·
Here's some inspiration for my Super Hawk builds:











 

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Discussion Starter · #7 ·
Will this one do?




CR77 Replica Specifications

Engine type: .................. Four stroke twin, 180 degree firing DOHC with two valves per cylinder

Bore & Stroke: ................ 65 x 54 mm

Power @ RPM: .................. 52 BHP @ 12,000

BEMP: ......................... 175 PSI

Power Band: ................... 8,000 to 12,000 RPM with a safety zone of 1,500 RPM extra

Primary Drive: ................ Straight cut gear w/idler, 19-63 (3.31:1)

Clutch: ............................ Multi-plate, Dry

Transmission: ................. Five speed, constant mesh

Gear Ratios: .................. (1) 1.898 (2) 1.459 (3) 1.254 (4) 1.192 (5) 1.000

RPM Drop @ upshift: ........... (1) 27%, (2) 21%, (3) 11%, (4) 8%

Ignition: ..................... MotoPlat Magneto, pointless ignition one sparkplug (14mm) per cylinder

Carburetion: .................. Two Keihin 31mm smoothbore, dual cable operated. Main Jet #110, Jet Needle # RH3, Needle Jet 2.6mm, airbleed type, air jet #250, pilot jet #55, cutaway 2mm, float valve 2.5 mm

Oil Pump: ..................... Twin gear type, low volume, supplying engine and transmission.

Valve Diameters: .............. Inlet 23.6mm, Exhaust 22.0mm

Port Throat Diameters: ........ Inlet 21.0mm, Exhaust 18.7mm

Valve Lift: ................... Inlet 7.0mm, Exhaust 6.0mm

Valve Springs: ................ Dual 70-80lbs on seat, 120-130lbs open

Valve Overall Length: ......... 100mm

Valve Guide Length: ........... 55mm

Valve Weight: ................. 26.9 gm (With retainer, keepers, and 1/3 of spring weight 79.6 gm)

BTW, I've talked with a fellow who built a CR77 Replica with the Suzuki GS400 topend and gotten the details about it and it IS quite involved (more than I am capable of dealing with). :|
 

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bill440cars said:
Anyone know any details on this Super Hawk with the 450DOHC Top End? Looking for the details, if possible. Any input would be appreciated. ;) Check out the "Dry Clutch also"! :cool: Found some info on adapting the top end from a Suzuki GS400 once but can't find it now, so assistance on finding THAT would also be appreciated. ;) Both conversions would not only give it the DOHC, but would increase the engine size also. :cool:



Its a CB77. With a CB450 barrel, head and G-box in it. The converion is NOT easy and to be honest, distroys most of the CB77 internals. All that is left is the outer "shape" of the crank-cases. The hubs are RC replicas made by a guy in Hungary, the carbs are moderm Keihin CRS's.

Stevie
 

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Discussion Starter · #9 ·
Stevie_d13 said:
bill440cars said:
Anyone know any details on this Super Hawk with the 450DOHC Top End? Looking for the details, if possible. Any input would be appreciated. ;) Check out the "Dry Clutch also"! :cool: Found some info on adapting the top end from a Suzuki GS400 once but can't find it now, so assistance on finding THAT would also be appreciated. ;) Both conversions would not only give it the DOHC, but would increase the engine size also. :cool:



Its a CB77. With a CB450 barrel, head and G-box in it. The converion is NOT easy and to be honest, distroys most of the CB77 internals. All that is left is the outer "shape" of the crank-cases. The hubs are RC replicas made by a guy in Hungary, the carbs are moderm Keihin CRS's.

Stevie
Thanks for that Stevie, I knew it was a 450 top end, didn't know the rest. Although I had heard that it took alot of aluminum rod, to get things ready for the conversion and that there was a 500cc version. I'm looking to get a bit more "guts" and speef out of it, if I can (on a limited budget).
 
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