Topic: CR750 wheels, advice needed

[Jadahonda]

I have for a longer time been thinking of building a CR750 Dick Mann replica or a CR750 kit bike, and have decided to build a kit bike.

Rear Wheel:
I have a replica rear hub that was casted here in Norway many years ago, and have now finnished it. I know that the rear wheel is 18", but what is the width on it?
Is there someone who sell drilled Borani rims or similar? Shall it have stainless steels spokes or zinked steels spokes?

Front wheel:
As fare as I know Honda delivered 19" rim at the first, and later 18" What is the width on this? And is there someone who sells rims and spokes for this?
Jan

[napoleonb]

I've got 3 different partslists and there is some difference but this is the info on the wheels:

44606-300-970   SPOKE A, front   20      Used on aluminium rim #9 washer, nipple. With nipple, rear
44607-300-970   SPOKE B, front   20      Used on aluminium rim #9 washer, nipple. With nipple, rear
44701-300-970   RIM, front wheel   1   44701-300-970   Aluminium rim 1.85B - 19

42311-300-970   COLLAR, rear wheel side   1      
42313-300-970   COLLAR, side, rear brake panel   1      
42601-300-970   HUB COMP., rear wheel   1      
42606-300-970   SPOKE A, rear   20      #9 washer, nipple. With nipple, rear
42607-300-970   SPOKE B, rear   20      #9 washer, nipple. With nipple, rear
42701-300-970   RIM, rear wheel   1   42701-300-970   Aluminum rim 2.15B - 18

However in the 5th partslist there is a slight deviation in regard to the RIM, front wheel, unfortunately there is no further background info on measurements (besides knowing it is 18" and most likely still 1.85B):
44701-300-971       RIM, rear wheel      1

The original rim's were most likely DID, but I never found those for sale btw.
My rims and spokes were done by a local company specialised in wheels, I could chose between butted or straight spokes and a variaty of rims and they laced them in for me.

[Jadahonda]

Many thanks!

I also have found that the first verion of the front rim had number 44701-300-970 who was 19", and that the later 971 was 18". Can anyone confirm that both is 1.85" wide?

From one picture I have seen it looks like the spokes is single butted Zn-plated spokes, but it would be nice if someone can confirm this.

The original CR-rims was DID rims, and was stamped "CR750" 3 places on each side.

Jan

[Sam Green Racing]

Member Ken736 sent all the specs to me which I posted in the Daytona thread.
I just found it but the link no longer works.
You could try asking Ken if he still has the info, here's his profile  http://forums.sohc4.net/index.php?action=profile;u=4838

Sam.

[Jadahonda]

Many thanks
Jan

[napoleonb]

The rear wheel has butted spokes so for one its more than a fairly educated guess the front wheel should also be butted.
The last pic is not very clear but if you look closely at the top of the hub on the far side you can slightly notice a butted spoke contour.

I did see some picture's of DID being stamped into the rim between the spokes, but never saw or heard anything on CR750 stamps do you have pics?

[turboguzzi]

borrani are still at it, just around the corner from my house

not sure they have the dimensions you need though

http://cerchiorecord.com/en/gamma.php

motocicliveloci are their agents

[Tintop]

Thanks for posting that link TG.  From the #'s above that would make the front a WM2 40-18. and the rear a WM3 40-18.  Both would appear to be available from the list posted.

[Jadahonda]

I will add a photo who shows the "CB750R" stamps later. A friend of mine have restored a factory kitted CR750 a couple of months ago for a customer, and he was able to get a pair of original CR rims. On the front, it was the late 971 rim who is 18"

If no one here is able to confirm the width on the rim, I will try to get in contact with the new owner and ask him.

Jan

[Jadahonda]

Here is the photo of the rim. Both front and rear rim is stamped "CB750R" 3 places on each side. It also has the normal DID-diamond stamp beside the air filler cap.

[Jadahonda]

I am adding a photo of the rear hub / spokes also who showes the single butted stainless steel spoke. He says that they are reproduction of original CR750 spokes, but I am still unsure if they used stainless steel. Other photo's I have seen showes Zn-plated spokes.

Any information is welcome

[Tintop]

Those SS spokes look like the ones Buchanan supplied me for the 18" Borrani I used.

[Sam Green Racing]

Jan, very few bike looked or were the same, It was a kit that was offered and you bought the parts you thought your pocket could afford. I wonder how many people went to the trouble of having the swingarm modded to like the one in the last picture?

Sam.

[Jadahonda]

Yes, the spokes is made by bucanans.

Sam: I agree With you that a Complete 970/971-kitted bike is difficult to find. There is also some differenses between the Daytona bike and the kit Honda sold later, as fixed clipons on the daytona bike vs. the hinged clipons that was offered in the kit. As far as I know, it is the same with the rear shock absorbers. In the kit they was made to fit the original lugs, so whats done in the photo is wrong on a kit bike after my opinion.

So, my goal is to build a replika based on the parts that was deliverd as 970/971 parts from Honda, and not a "Dick Mann/Daytona replica. To do this, I will try to collect as much information as possible for the 970 parts.

What about making a tread for documentation of 970/971 parts here?
Jan

[Sam Green Racing]

WE did have that list Jan but the link to it failed, there was a lot of tech specs and modifications added to it, did you not contact Ken736?

Sam.

[Jadahonda]

I have not done it yet, but I will....
Jan

[Retro Rocket]

WE did have that list Jan but the link to it failed, there was a lot of tech specs and modifications added to it, did you not contact Ken736?

Sam.

Try Mark at M3 racing....

[H2Eric]

Jan, very few bike looked or were the same, It was a kit that was offered and you bought the parts you thought your pocket could afford. I wonder how many people went to the trouble of having the swingarm modded to like the one in the last picture?

Sam.

I got my swinging arm done that way
Cheers
Eric

[Jadahonda]

Eric:
Yes I have seen that, you are building a very nice Dick Mann replica, and on that bike this is the right way to do it, but not on a CR750 if I am right???

What size on rims and tyre do you use on it?

[H2Eric]

Eric:
Yes I have seen that, you are building a very nice Dick Mann replica, and on that bike this is the right way to do it, but not on a CR750 if I am right???

What size on rims and tyre do you use on it?

Hi Jan
The wheels on my bike are WM3 front and WM4 rear, both are 18inch. Tyres are Dunlops.
I tried a WM2 x 18 on the front, but it didn't look right. However if anyone is interested in a Borrani style alloy WM2 x 18 rim with 40 holes let me know. Although its has been laced to a hub and has had a tyre on it, it has never been used.

Cheers
Eric

[MFHP]

Hi Jan,
as far as I know, WM3 2.15X18"  in the front and WM4 2.5X18" in the rear  is the correct size.

Mike

[JohnN]

I think the scan attached is from the broken link Sam mentioned. It lists 1.85 front and 2.15 (WM2 & WM3) rear which would make sense for tires available at the time. I have WM3 & WM4 installed on mine for use with modern (treaded) race tires. This is also the largest width allowed by some vintage club rules.

John

[Jadahonda]

Many thanks for all good advice, and sharing information about the wheels. From what I have seen, I will use a borani 1.85x18 in front with 3.25.18. This will be same as the -971 version of the rim and a 2.15x18 with a 4.00x18 rear. As far as I can see, this is right for a CR750-kitted bike. This is also the same that I got from Ken. (and the scan in the post above)

When I look at photo's of the dick mann bike, you can clearly see that the front wheel is larger than the rear, but I have no idea about the width on them.

Jan