Author Topic: The 1970 Daytona CR750s. (Read 267075 times)

voxonda · « **Reply #350 on:** March 16, 2009, 11:42:01 PM »

Quote from: City Boy on March 16, 2009, 10:02:26 PM

Hi.With all due respect,I must disagree that the CR gearbox is horrible.I have one in my unit.Now,when I ride on the street it is tedious to get rolling.However,when I have road raced the bike,the close ratios become a blessing.The stock 1st gear now becomes useless at any circuit that does not have any ridiculously slow corners,whereas the CR first gives you a full 5 usefull speeds.I gladly accept the less than steller start for an extra usefull gear every lap.Not only that,I ride smiling inside with the knowledge that as long as I treat it nice,the tranny is an appreciating asset tee hee. Rock On

Hi city boy,

You're absolutely right about the fact that once rolling the box is fine, but getting it of the line in competition has cost quite a few clutch plates.
Let's Rock on.

Cheers.

City Boy · « **Reply #351 on:** March 17, 2009, 06:33:31 AM »

Hi voxonda.I quite agree re the clutch.Muchos TLC required leaving from stop.This is especially acute on street with gearing to give reasonable cruising rpm.For any of youse unfamiliar with a CR gearbox 1st gear is numerically same as 2nd in stock box. Still Rockin after all these years!!

kos · « **Reply #352 on:** March 17, 2009, 08:10:59 AM »

You made my point...exactly! First gear renders the CR box... a close ratio 4 speed. We tried those CR boxes, but the real gear box to use is Nova. Won Daytona 7 times and set all time lap record with it, along with Highest top speed ever for Vintage/Classic bikes at Daytona...155.556 MPH.

And...I sell them

We used stock OEM Honda plates (Metal & Fiber) and never had a probelm leaving the line. In fact...never lost a hole shot in 6 years. Adam, would hold throttle at 7500-800RPM and slip the clutch until full engagement., while never changing throttle position. Changed fiber plates after two race weekends and rotated the back (slightly burnt) metal plates at the same time towards the front of clutch pack.

KOS

voxonda · « **Reply #353 on:** March 17, 2009, 08:30:32 AM »

Well, I think our rider did not have the skills of Adam. Though he was a very good rider even in International events, but never really got that 'kitted' Daytona 750 off the line properly. When we had to push start them no problem. When I think of it, push starting these things.

IMHO these were the real "iron men", R.E.S.P.E.C.T

BTW our rider is not in these pic's.

benly- ben · « **Reply #354 on:** March 17, 2009, 03:21:59 PM »

heres me dad at the pod.

Ben

City Boy · « **Reply #355 on:** March 17, 2009, 08:13:10 PM »

Hi Kos.I had no idea that Nova box has different ratios than 970 assembly.What are the ratios ,if you wouldn't mind posting them for my records?I am very aware of your competition records;Kudos to you.My only track experience with my c.r. box was at Mosport Park,where first gear was perfect for the slowest corner on the circuit,Moss,namesake Sir Stirling hisself.This leads onto the fastest straight so all five speeds were used for the long uphill climb.I guess I only posted cus it took me aback that you felt the kit trans. was horrible.I understand better now the context that you meant. Rock On

lordmoonpie · « **Reply #356 on:** March 18, 2009, 05:04:48 AM »

Quote from: City Boy on March 17, 2009, 08:13:10 PM

Hi Kos.I had no idea that Nova box has different ratios than 970 assembly.What are the ratios ,if you wouldn't mind posting them for my records?I am very aware of your competition records;Kudos to you.My only track experience with my c.r. box was at Mosport Park,where first gear was perfect for the slowest corner on the circuit,Moss,namesake Sir Stirling hisself.This leads onto the fastest straight so all five speeds were used for the long uphill climb.I guess I only posted cus it took me aback that you felt the kit trans. was horrible.I understand better now the context that you meant. Rock On

Nova ratios are not as dramatic as the 970 box - BUT, Nova customer service for their parts is damn awful. Their response to customer problems is "well it works on my bike". I have had two years of problems dropping their boxes into a CB450 and a CB750 that was standard until the gearboxes went in. They have been no help at all and the three faults (gear selection failure, transmission locking and dipstick chewed off by gearbox) were all down to design faults in Nova's products, AND they damaged the nova dry clutch I was also running. Nova refuse to replace the damaged part, damage casued by their products!

Caveat Emptor - they're not cheap to then have to spend lots of time and money putting their design errors right....

bwaller · « **Reply #357 on:** March 18, 2009, 05:41:51 PM »

Like your pictures Rob. The "Le Mans" starts were always fun, gave us Jap guys an edge over the British stuff, plus I could really get across the track quickly!

City Boy probably remembers those days too.

City Boy · « **Reply #358 on:** March 18, 2009, 10:20:06 PM »

Hi bwaller.I sure do.In fact ,I guess I'm a true dinasaur but I think it added to the fun! Rock On

kos · « **Reply #359 on:** March 19, 2009, 08:26:10 AM »

Nova vs Kit (970) box

CR750
1st 24/41 1.708
2nd 27/38 1.407
3rd 30/36 1.200
4th 31/33 1.065
5th 34/31 .912

NOVA
1st 18/37 2.056
2nd 22/33 1.500
3rd 25/31 1.240
4th 31/33 1.065
5th 32/31 .969

FYI... F2 Engines have ratio changes on 4th and 5th and that can work well on a road racer. Most street bikes have very high overdrive ratios in top gears and this is always hard to overcome when areo loads are highest and engine cannot be run in "sweet spot" of power curve.

KOS

voxonda · « **Reply #360 on:** March 19, 2009, 01:19:10 PM »

Hi Mark, any luck with the pic's?

Cheers, Rob

City Boy · « **Reply #361 on:** March 19, 2009, 04:47:35 PM »

Thanks for the #'s kos.Glad you included those for 970 also;Went looking in my notes from a less organized time and drew a blank.

kos · « **Reply #362 on:** March 20, 2009, 04:19:40 PM »

Sorry, I am having problems loading... as the photos that were sent to me were done by a "pro" and the mega bites are huge!

Any ideas?

KOS

turboguzzi · « **Reply #363 on:** March 21, 2009, 01:09:28 AM »

there are quite a few programs to re-size images, guess that if you are asking then it means you dont have photoshop which is the most professional

either download an advanced viewer/editor like Thumbs or you could try to email them to yourself through hotmail or AOL. these mail services will resize big pics for mail friendly dimensions.

When you reopen the mail simply save the smaller pics and then post them here

Ricky_Racer · « **Reply #364 on:** March 22, 2009, 07:06:32 PM »

Mark, if it will help, just email the photos to me. I'll resize and optimize them and send them back to you in just a couple minutes. I set up a script in Photoshop.

Lemme know if I can help. RR

Johnnie · « **Reply #365 on:** March 24, 2009, 02:04:03 AM »

Quote from: voxonda on February 24, 2009, 02:53:23 PM

Well not a CR but it is from that era and it is coming slow but it is getting there:

One of Gordon's framekits.

Very sturdy, but light, 20 m/m front axle.

Pic's are taken some weeks ago, in the meantime waiting for the light alloy wire wheels with genuine Dunlop TT100 tires. Frame is almost ready for blasting and painting.
Cheers, Rob

Hi Voxhonda

Are those old style Keihin CR carburators in the first pic??

Thanks

voxonda · « **Reply #366 on:** March 24, 2009, 03:42:57 AM »

Hey Johnnie,

No, regretably not, these are OEM carbs.

Cheers, Rob

Big Bob · « **Reply #367 on:** April 04, 2009, 01:16:16 PM »

Quote from: kos on March 20, 2009, 04:19:40 PM

Sorry, I am having problems loading... as the photos that were sent to me were done by a "pro" and the mega bites are huge!

Mark, for chrissakes I hope you're not talking about me!

CR750 at Roebling Road, that's my buddy Garry on the 554 bike:

Fighting it out on the front straight:

Hauling ass:

Big Bob · « **Reply #368 on:** April 04, 2009, 01:22:31 PM »

And just for my own gratification....

Me dragging a knee on my Production Heavyweight CB 750 at Daytona:

Just a split second from taking first place on Tuesday:

And this is me standing next to the guy I beat. Pic was taken just after he beat me on Monday. If we're gonna make this fair he needs to carry about 150 pounds of ballast:

voxonda · « **Reply #369 on:** April 04, 2009, 02:36:02 PM »

Thanks kos and Big Bob, beautiful pic's.

Cheers, Rob

mikeb4 · « **Reply #370 on:** April 04, 2009, 04:30:48 PM »

Awesome pics! that looks like a lot of fun ... seems like a timewarp flashback!

Thanks for posting......

Retro Rocket · « **Reply #371 on:** April 04, 2009, 05:24:11 PM »

Awesome pics, thanks Bob. Vox, i have a good set of the 31 CR's with the ticklers from the CR750 race kit......Interested? I was thinking about swapping these for 2 sets of modern CR29's, either that or put them on flea bay.

Mick

voxonda · « **Reply #372 on:** April 05, 2009, 02:35:36 AM »

Quote from: retro rocket on April 04, 2009, 05:24:11 PM

Awesome pics, thanks Bob. Vox, i have a good set of the 31 CR's with the ticklers from the CR750 race kit......Interested? I was thinking about swapping these for 2 sets of modern CR29's, either that or put them on flea bay.

Mick

Hey Mick, interested...............Wish I had the funds at this moment, would be a dream come true! Man oh man I would like to buy them from you.

Cheers, Rob

Ricky_Racer · « **Reply #373 on:** April 06, 2009, 08:44:23 AM »

Mick, can you confirm that the CR900 (31mm) tickler carbs will fit a CB750 SOHC by using DOHC intake rubbers?

If not, do you have any other tips for mounting them? If not, does anybody??? Thanks! RR

Sam Green Racing · « **Reply #374 on:** April 06, 2009, 02:41:57 PM »

Sad day guys.

http://www.bonhams.com/cgi-bin/public.sh/pubweb/publicSite.r?sContinent=EUR&screen=LotDetails&iSaleItemNo=4230025&iSaleNo=17358&iSaleSectionNo=2&sServer=http://images1.bonhams.com/&sPath=2009-03/19/7832695-1-1.jpg

Sam.

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Author Topic: The 1970 Daytona CR750s. (Read 267075 times)