Topic: CR750 clutch basket....

[MRieck]

Anyone on the board seen a real factory CR clutch basket?? If so how was/where was it lightenend. Also. did they drive the oil pump off the basket directly or did they use the kickstarter gear. I have seen kit Kawasaki parts for the old Muzzy Raptors and ZX6's and the amount of lightening performed to the shift drum, transmission gears and especially clutch basket is incredible...beautiful stuff.

[Sam Green Racing]

Hi Mike,

You are in luck young man as I personaly know all four of the origional factory riders.
Team leader Bill Smith, Tommy Robb, Ralph Bryans and Steve Murry, Steve being the first person outside of Japan to pull a motor down, to dump the electron crank cases, as they leaked like fcuk.
Although Steve still races at International level he is rather old and has difficulty remerbering things as I have asked him several questions regarding our bike.
I will phone him tomorow night if he is in the country and will get back to you then.
How did your camping trip Go ? good weather I hope.

Regards Sam.

[MRieck]

I had a feeling you'd know something about it Sam.

[Sam Green Racing]

OK Mike,

after a lengthy phone call to Steve, he allways starts with I can't remember then it all comes flooding back.
The clutch and oil pump drive are all as stock CB750.
He said they where just about the only components that were not modified and gave no trouble at all.
When you think about it, our bike has done three seasons sprinting/drag racing on a stock clutch and that is the part that gets the most abuse.
When we had trouble with the clutch cable I pulled the clutch apart and the springs and friction plates all measured up to full/new spec.
Hope this is of use to you mike as you have been a great help to us.

Regards  Sam.

PS just a though, if you go ahead and lighten the basket how much will it afect the balance of the shaft.
I fitted a set of kevlar plates in my NC30, they was lighter than stock and they caused the bike to vibrate like hell.
When I changed back to stock honda plates the problem was gone.

Sam.

[Sam Green Racing]

 

[MRieck]

Well...first I'd like to say Sam thanks for your effort....you're a "Diamond Gezzer". Now that's a very good point about lightening things and more vibration. I've had a lot of experience with large FJ engines and that. That inculdes lightening the crank with a heavy duty basket, no lightening and a heavy duty basket and a lightening crank with a stock basket. The worst combo for vibration was the lightened, balanced crank with the stock,unbalanced basket. If i balance the lightened basket it will be all good. I think??

[Sam Green Racing]

Do you have a spare basket if it don't work ?

Bought a pair of high comp pistons for my old Benly to take it from 8.7 -1 to 10-1, also a set of valves and a full gasket set of ebay for $99.
All up about £70, To have bought them over here (can't) would have cost about £185.
Thank God for ebay USA.

Steve Murray that I spoke to was the guy that had to give up his ride to Dick Mann, perhaps he could have been the winner in 1970.
He also said that Bob Hansen was well into CR750s if you can find his details over there, but he said he had had a stroke last year and was'nt sure of his health now.

Regards Sam.

[Sam Green Racing]

 

[MRieck]

Hansen is really old now Sam. I have not had the pleasure of meeting him BUT he was instrumental in Honda's USA effort. You are lucky to know those man...I think Bryan's bike burnt to the ground at Daytona. I have excellent ideas on how to modify the baskets and better yet an absolute genius machimist to carry it out. This man does all the Penske F1 car suspension stuff etc.. real secret #$%*...a smart, fine bloke. You always have in on anything I do sir. You'd be surprised what a light, well balanced basket can do.

[Sam Green Racing]

Mike,

Any weight loss has to be a good thing, but at times it don't allways work.
Take the CR with me on it it's all wheel spin but a lot faster over the line but that don't win drag races.
Chris is almost twice my weight, slower at the top end but gets there quicker because his mass makes the tyre grip in the lower gears.
My Benly in stock trim weighed in about 275lb and was lucky to see 70mph.
When I got it down to 175lb the speed went right up to 87mph on the same gearing.
This weight loss took 4secs of its quater mile time.
We can but try.

Sam.

[MRieck]

Sam
 What kind of tire are you using?

[Sam Green Racing]

Not sure Mike, What would be on a stock bike size wise, but in race rubber.
It's just that I don't ride it often enough to get used to it , and the tyre pressures are not right, but he won't mess around with them.
when all said and done it's his bike.
I will give you some times to ogle at when I get my Benly back on the strip.
What did you mean in that PM , somthing about a sence of humor?

Sam

[Sam Green Racing]

 

[Sam Green Racing]

Mike it's a 120 18 Avon race tyre.

Hows things.

Sam.

[MRieck]

Doing OK Sam. Busy with bike work and watch work.

[Sam Green Racing]

Mike, a larger tyre will fit in but Chris wants to keep it as period as possible wherever he can.