Author Topic: Rickman CR750 with RC Engineering Cobra motor 1975  (Read 4908 times)

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Offline colined2

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Re: Rickman CR750 with RC Engineering Cobra motor 1975
« Reply #25 on: June 05, 2015, 05:31:18 am »
CB750 K4

Offline colined2

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Re: Rickman CR750 with RC Engineering Cobra motor 1975
« Reply #26 on: June 05, 2015, 05:32:45 am »
Another

Offline colined2

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Re: Rickman CR750 with RC Engineering Cobra motor 1975
« Reply #27 on: June 05, 2015, 05:34:20 am »
Last one.

Offline mick7504

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Re: Rickman CR750 with RC Engineering Cobra motor 1975
« Reply #28 on: June 05, 2015, 07:00:41 am »
That's a great story Colin.
I'm curious as to how you were allowed to get that bike inside the house mate because occasionally someone reminds me about 2 wheels being parked in the lounge room from many years ago.
Keep up the good work mate.

If I was you
I'd be worried about me.

Offline hondaron

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Re: Rickman CR750 with RC Engineering Cobra motor 1975
« Reply #29 on: June 05, 2015, 12:13:53 pm »
It's a small world, I emailed Colin as I just knew I knew him, thanks for the response Colin, not the Colin I was thinking.

I thought this was Colin Edwards Sr., father of World Superbike Champion and Moto GP rider Colin Edwards, when I met Colin Sr. in the late 70's he was riding a Rickman Honda 750, with an RC engineering Cobra motor with a Supercharger.

So reading this story I thought it had to be his, as he was originally from Australia............. what are the odds of two Colin Edwards both from Australia, both with Rickman Honda 750's ?

Colin Sr is in Conroe, Texas now.

Thanks for the stories and the pics Colin  :) :)

Offline Medyo Bastos

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Re: Rickman CR750 with RC Engineering Cobra motor 1975
« Reply #30 on: June 06, 2015, 06:13:09 am »
Honda Japan's answer was to fill in with weld the detent arm on the gear change mechanism where the spring connects and to reduce the diameter of the wheel or roller or whatever you call it on the detent by 1mm.BINGO no more gearchange problems.

please elaborate on this for us...

Offline colined2

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Re: Rickman CR750 with RC Engineering Cobra motor 1975
« Reply #31 on: June 06, 2015, 08:36:48 am »
Hello Medyo
It has been a long time since I modified the gearchange mechanism but if you take off the gearchange cover there are 2 arms in the mechanism, both spring loaded, on the left is the arm with the small wheel that rides on the thick outer washer with the notch in it, the detent arm in question is the inner one that goes to the right, the wheel on this one moves amongst the pins on the end of the selector drum as the gear lever is operated.I can only assume that welding the notch where the spring locates gives it more tension and the smaller size of the wheel helps lock it in gear.I never gave the technical side of this much thought but after I did it no more problems.I hope this helps.
Regards
Colin

Online PeWe

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Re: Rickman CR750 with RC Engineering Cobra motor 1975
« Reply #32 on: June 06, 2015, 12:51:15 pm »
Very interesting improvement to know in detail with photos.
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 colined2

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Re: Rickman CR750 with RC Engineering Cobra motor 1975
« Reply #33 on: June 06, 2015, 07:20:12 pm »
PeWe and Medyo
Good morning from a very cold Melbourne 12 degree's C. and a strong wind.
I hope this comes out OK.
Just to refresh,my Cobra motor from 1974 jumped out of 2nd,3rd,4th and 5th,after back cutting dogs on gears problem not fixed.On Honda Japan's instructions fill in the notch on the Drum Stopper (indicated on the scan) and also decrease the overall diameter of the wheel (indicated as well) by 1mm.
If you are having jumping out of gear problems and you have modified the dogs on the gears then you have nothing to lose by trying the above modifications.If you don't have a spare Drum Stopper detent arm I'm sure you could pick one up quite cheaply.This would sure be better than tearing down the motor for another look.
It worked for me.
Regards
Colin Edwards

Online PeWe

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Re: Rickman CR750 with RC Engineering Cobra motor 1975
« Reply #34 on: June 07, 2015, 05:18:30 am »
Colin, thank you very much from a windy, grey Sweden. + 17.8C at 02.17 pm
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 Medyo Bastos

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Re: Rickman CR750 with RC Engineering Cobra motor 1975
« Reply #35 on: June 07, 2015, 05:21:08 am »
ah, all is clear now, thank you for your efforts


...Save a tree, eat a beaver...

Offline Greg H

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Re: Rickman CR750 with RC Engineering Cobra motor 1975
« Reply #36 on: June 07, 2015, 10:03:32 am »
Nice one Colin ;) . I'm in the process of building a motor which will be fitted with undercut gears ,so I may incorperate that mod .

Offline Rickman88

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Re: Rickman CR750 with RC Engineering Cobra motor 1975
« Reply #37 on: November 26, 2015, 01:25:10 pm »
Hi,

Where can I find this fairing?

I need it and the front mudguard

regards
Rickman Honda from Barcelona, Spain :)

Offline hondaron

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Re: Rickman CR750 with RC Engineering Cobra motor 1975
« Reply #38 on: November 26, 2015, 01:42:33 pm »
Reproductions of the Rickman Honda 750 fiberglass parts are available from air tech
Check out www.airtech-streamlining.com


Offline Rickman88

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Re: Rickman CR750 with RC Engineering Cobra motor 1975
« Reply #39 on: November 28, 2015, 08:06:50 am »
Reproductions of the Rickman Honda 750 fiberglass parts are available from air tech
Check out www.airtech-streamlining.com

The main problem is that I'm from Spain, Europe so the shipping fees and customs are expensive :(

I'm trying to search something in England right now  :(
Rickman Honda from Barcelona, Spain :)

Online PeWe

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« Last Edit: November 29, 2015, 09:46:02 am by PeWe »
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