Web Site Changes

[Steve Swan]

All these small insignificant details in 1969 are today very very interesting!!
There should be several manufacturers in subcontracts for the manufacture of the wrinkle gas tank??
Who can give other explanations?

Perhaps the Japanese.  

My personal assumption, in the case of 17L tank differences, the bottom pans of the tanks were a result of tooling changes.

[4pots1969]

Yes Steve, it's a good assumption...
But why have they not made the effort to delete these not very pretty wrinkles when you open the fuel tank when they did new matrices?
You would think that they were necessary and even planned by the Honda factory engineers to reduce and absorb the deformation of the sheet metal during stamping??
A problem solved maybe after by a different sheet thickness?
Mark, shells without wrinkles have different weights who are wrinkled?

[Wayne]

KP. Thank you for taking the time to provide some additional great pictures and details. I'll sift through it hopefully today and hopefully closeout the fuel tank area and then we can move on to the Fuel Tank Caps. I don't know if we have learned any more since the info was written on the current web page: http://cb750sandcastonly.com/support12.htm

[Wayne]

I have cropped a couple of your images KP and got them pointing in the same direction for comparison purposes. Let me know if I missed anything that should be noted. I'll also do am image noting the absence of wrinkles in the side of the late tank.

[Wayne]

And lastly the tunnel comparison between a "mid run" and late production tank. I'll update the web page as soon as I have a green light on that last 2 posts, images.

[hondasan]

My view would be that the late (fourth type) wrinkle tank is likely to be from a die-cast VIN, a result of the tooling being refined as production progressed.
Given the rate at which a power press can turn out  pressings such as this, there would only ever have needed to be one tool in use at any one time. As the tooling wore and was re-furbed or replaced, it most likely evolved to produce smoother (better) pressings, which would in turn reduce the force required by the press, and the subsequent rate of wear of the tooling.

Once upon a time , it was easy - flip the filler cap and check for wrinkles. Now we are faced with four possible versions of the wrinkle tank + the Yamiya version. The restorers dilema!

Chris R.

[Wayne]

My view would be that the late (fourth type) wrinkle tank is likely to be from a die-cast VIN, a result of the tooling being refined as production progressed.
Given the rate at which a power press can turn out  pressings such as this, there would only ever have needed to be one tool in use at any one time. As the tooling wore and was re-furbed or replaced, it most likely evolved to produce smoother (better) pressings, which would in turn reduce the force required by the press, and the subsequent rate of wear of the tooling.

Once upon a time , it was easy - flip the filler cap and check for wrinkles. Now we are faced with four possible versions of the wrinkle tank + the Yamiya version. The restorers dilema!

Chris R.

So my dilemma. Do I add the 4th version to our web page? IMHO the Technical and distinction's area of our site is to identify and distinguish between parts that were used in the various production range of the "sandcast" CB750. I'll use the same argument here as I did with the Yamiya tank earlier in this thread. Where do we stop in putting up different tanks, or tank that didn't come on a sandcast machine? Let the debate begin on version 4.

Having said that, the information is valuable for phase 2 down the road. The dedicated K0 part of the site.

[4pots1969]

Now we are faced with four possible versions of the wrinkle tank + the Yamiya version. The restorers dilema!
Chris R.

Just a digression...
Must be added to version Yamiya yet another version of copy for the Wrinkle Gas Tank perhaps more "dangerous" than the version from Yamiya...

[Steve Swan]

Yes Steve, it's a good assumption...
But why have they not made the effort to delete these not very pretty wrinkles when you open the fuel tank when they did new matrices?
You would think that they were necessary and even planned by the Honda factory engineers to reduce and absorb the deformation of the sheet metal during stamping??
A problem solved maybe after by a different sheet thickness?
Mark, shells without wrinkles have different weights who are wrinkled?

I doubt non-visible wrinkles were important to mass unit production.  Proper fitting tank was important.  Your, point on gauge of sheet metal used is a possible reason the wrinkles changed or disappeared.

[hondasan]

My argument to include version 4 of the wrinkle tank would be to ensure that those that pursue 100% perfection know there is a wrinkle tank version which is not correct for sandcast machines.

I acquired this tank at a very favourable price with the intention of putting it on #5298 (which in my 24 years or ownership has never had a wrinkle tank), not realising it to be incorrect to this VIN. That said, I am pleased to have it and will fit it to #5298 which is a long term rider, and will from now on at least pass the filler cap inspection test!

Cheers - Chris

[kp]

I have a question
Why didn't the earlier Honda including the CB450 tanks have wrinkles 

[markb]

They took them out of the dryer right way.      Oh wait, is this a trick question?

Sorry KP, that's a helluva good question.

[kp]

They took them out of the dryer right way.      Oh wait, is this a trick question?

Sorry KP, that's a helluva good question.

Hey Mark, I like your thinking 

[DW69K0]

Actually, the 1965-67 Honda CB450 K0, AKA the Black Bomber had wrinkles in the back of the tank.
I own five and know them well.
Duane

[DW69K0]

Oops, bad picture, let me try this again.
Hope this one loads correctly.
DW