Honda CB750 Sandcast

Original-looking tires

DW69K0

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Clearly a Bridgestone on 2113 prototype Sandy.
DW



CBman

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Also green Las Vegas bike had Bridgestone tires. But production bikes had Dunlop F3 and K87. I will search in my library, but in one of first US magazine test there was written F3 and K87.


Steve Swan

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hmmm.   parts book calls for BS.  the pre-production display bikes have BS tires.  So far, it seems production bikes had Dunlops fitted. ????


DW69K0

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1969 Cycle World article, here is a picture from the rear of the test bike.
Best,
DW


Steve Swan

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Aug.69 CYCLE records Dunlop, F3 and K87.

MOTORCYLE WORLD, MARCH 1970, documents road test on machine with engine CB750E-1000024; Dunlop F3 and K87 fitted  MOTORCYCLE WORLD notes they had to wait for a 750 machine to tests, because the larger circulation magazines got the machine before they did.  Color pictures were taken for the MC WORLD article, leaves on trees were turning, so it must have been late Autumn when MCW got #24 to test.  and MCW commented the tire was pretty much worn with 5200 miles on the machine.  of interest, the article also mentions "chain break and punch a hole in the cases of the Honda Four."  The article goes on to say, Honda reps said the fix was applied to the very earliest machines; fitting a tooth larger front sprocket.

So, this quick look through all my American magazines, all pictures appear to show same Dunlop tires which all appear to show same tread Dunlop tread design.  i will look through my Factory brochures for mention of tire brands, but that'll be a few days.

i am suggesting the possibility production machines (USA) were fitted with Dunlops and not Bridgestone.  Although the parts book calls for either brand, i seem to remember English Dunlop was a tire brand commonly available imported tire to US, whereas not in the case of BS.  And, the BS tire was a Japanese tire, i'm not sure how readily available to retail in 1969.

it sounds like the 4 pre-prod units came with BS tires....????  Perhaps BS is what the factory had available at the time to fit to these hand built non-assembly line produced machines ????  But, Dunlop was the tire choice for production assembly.  (and fwit, this was the time when relationship between Honda and Bridgestone was acrimonious, Honda telling BS to quit making motorcycles or we'll stop putting BS tires on our motorcycles?)  Who knows to be fact..... But these were some of the factors making up the production climate around that time that could affect decisions.  ANYBODY KNOW MORE ABOUT THE BRIDGESTONE/HONDA RELATIONSHIP, WHEN THIS HAPPENED, WHAT THE FACTORS WERE ?

Anyway, what one sees in the parts book or in literature does not always translate to what the bike ACTUALLY comes with.  So, perhaps, Dunlops were fitted to production lines, but the book called for either brand.  The book called and literature called for a number of things not seen on prod.bikes, example that comes to mind is early literature called for 4 colors and we know early bikes came in 2 only.

looks like falls back to the more early examples we can find with what appear to be original tires, is what we can use to theorize correct tire.

F3, F6, F11, these different  numbers, i imagine, designate improvements in tire carcass and compound and maybe tread design.  Thoughts anyone ?

My 4779, my ride to California, my rear tire was over half worn when i went to dealership in California May 1970.  i distinctly remember him telling me to take it ease so i could get back to Nebraska on the remaining tire.  Which, i did.  There was no center tread when i got home.  I remember waiting for a tire to come in, it was at least a couple weeks.  That tire came from Olson Brothers Honda Triumph.


Erling

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As I remember it the 125 Bridgestone racer was build to test their own tyres on but outperformed the tyres so a foreign brand had to be fitted!
As for 4 colours on original models might one be the grey on E vin 111 I distinct remember seeing on Nürburgring May 1970?
    Erling.


Sgt.Pinback

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Have a set of Dunlop Goal Seal.
Came on a CB750 in 1970 to Germany, been changed to European wheels and stored since then.  
« Last Edit: November 16, 2015, 08:55:59 am by Sgt.Pinback »
Cheers, Uli (Leonberg, Germany)



kp

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If Mr Swan doesn't buy them can i put my hand up
Thanks
Yabba Dabba KP


markb

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Probably way too late but my hand's up too.
Mark B
1969 CB750 sandcast #97 restored - Sold Restoration thread link
1969 CB750 sandcaxt #576 - Sold
1969 CB750 sandcast #1553 - Sold
1969 CB750 sandcast #1990 - Sold
1969 CB750 sandcast #5383 restored - Sold Restoration thread link
1970 CB750 K0 restored - Sold
2010 H-D Tri Glide Ultra Classic (Huh?)


Sgt.Pinback

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Thank you for the PN's and E-mails.

Actually, I just wanted to show the old profile of those tires for comparison and didn't intend to sell.

If so,  I have no idea what would be a reasonable price. Living in Germany I assume that shipping would be quite expensive to USA. How to ship tyres?

Next week I will pick up another low mileage German KO, diecast of corse, registered 03/1970. Will have to do an overhaul and maybe then will give her those tyres.

If not the set will go to somebody here.
« Last Edit: November 14, 2015, 10:49:02 am by Sgt.Pinback »
Cheers, Uli (Leonberg, Germany)


4pots1969

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The poor... Sgt.Pinback by kindness he makes you see his beautiful tires 1969 and you want all poking him...
This is not nice!!  >:( :D :D ;)
I try to have a little humor, because here in France a Paris since yesterday, it's very sad...


« Last Edit: November 14, 2015, 12:21:15 pm by 4pots1969 »



Erling

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My Sand Cast front wheel stands with original tyre on.
Dunlop Gold Seal F3.
Was only on for the first couple of month.
Then the Münch 250 mm drum brake from my BMW came on.
Though only 18 inch rim it did not handle any different!
Just touching more frequently the exhaust pipes underneath!
One thing is: there are double mutters on the air valve stem!
Is this common?
Matter of fact, never really spoke to a fellow Sand cast owner.
5 landed here simultaneously. Met 2 of them then just briefly! 
    Erling.


CBman

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Cant make this info 100% right, but F3 tire was used on about first 2000 Sandcasts. Later sandcasts had F6.