Topic: Oil Tank won't fit! Did I waste more cash, again?

[jrrobertsjr]

A bit of history. 1972 CB750 Frame that was bought as a rolling chassis. The rest of the bike was in 8 milk crates. I don't have a clue what was originally on the bike and what was rounded up from other CB750s.

Everything has been bead blasted and powdercoated.

I picked up my oil reservoir from the powdercoater yesterday and installed new rubber grommets to mount it to the frame.

It looked great until I tried to mount it to the frame.

The center of the grommet holes wouldn't line up with the mounting holes on the frame. I can force it but the grommets on the tank distort a great deal.

Additionally, the tank rubs against the frame and rubs hard. I mean it really pushes.

So my question is where did I go wrong? (Other than buying it.)

Are there different oil tank spacings on other CB750s? If so how can I find the right one?

If anyone has one, please let me know. I would be glad to trade you a shiny, new, acid-bathed, super clean, freshly powder coated oil tank.

I think the measurement on my frame across the top is 27cm center to center.

If anyone can help my out on this, I would really appreciate it. If you think you can help, PM me and I will get you my phone number or give you a call while I am in front of the bike.

Thanks,
Johnny

In this picture, only the bottom grommet is in. I pulled the other two to see if I was crazy.

[fang]

Without any other details, my first thought is that since you have European controls maybe the whole bike is an European.  Since I have never seen one of those bikes before all my thoughts are total speculation, BUT it might be that there are other differences too, such as the frame and/or oil tank mounts.

If this is the situation then the USA-spec oil tank you bought might not fit.


Can you send us the measurements between all three mounts on the tank and all three of the measurements on the frame.

Thanks and good luck!
-fang

[fang]

I went out and measured two of the frames in my garage at the moment

my 1976 measured about 29.4cm (11.56") across the top two oil tank mounts

and this is the interesting thing:
my early VIN 1969 frame measured about 27cm (10.63") at the same place -- just like yours!

I know some of the non-USA models trailed behind the USA models as far as changes went.  I am only guessing, but it all that is correct -- and your non-USA 1972 frame is the same as a 1969 USA frame -- then you might need a "sandcast" oil tank.

Who else out there has any thoughts on this?
-fang

[mlinder]

Yep, i tlooks like he needs the oiltank like mine:



Shaped differently, differnet mounting points. Our frame slook the same.

[jrrobertsjr]

OK... Good info. Thanks guys.

So it seems as there are different spacings on different tanks.

mlinder, from the pic, your tank looks like mine. Obviously, I can't see the difference in the spacing from the pics so what should I look for on eBay? What year is your bike and what years do you think would have the correct spacing?

I really appreciate the help guys. I wish I had mocked up that tank but I never thought that I would run into this issue.

My frame number is 2095104.

After checking out hondachopper.com...
Model      Sell Date     Release Date     Prod.           Code Frame #       Engine #
750K2       1972           03/01/72        341           CB750-2000001 - CB750E-2000001 -
 
Looks to me like I should be able to buy a 1972 oil tank and call it done but after reading Fang's thoughts, I am not so sure.

Could you take a close up pic so that I have something to compare it to.

Can't thank you guys enough. I would start over if I wasn't so far into this one.

The measurements are below. I hate to even post this since I really want to take them again but if I get better ones tonight I will post and let you know.

[mlinder]

I think the tank you have is hte later, rounde done. Mine is very square. It's a '69. I think the mounting points are slightly different too. I'll take pictures adn measurements later tonight after i get home.

[Bob Wessner]

The K0 tank, based on part number anyway, is different than the K1/K2. These two, based on part number, share the same oil tank.

[jrrobertsjr]

Thanks 1hotz.

If it doesn't fit I'll be glad to send it back.

I really appreciate the gesture. You don't see stuff like that on the other boards.

I went out to the garage to take more measurements. August in Houston. It had to be 150 degrees in there.

This is my best approximation.

The triangle at the top is pretty accurate and since it is the frame, these are the measurements I am looking for.

I did my best to measure the tank to show how its off.

If it wasn't pressed so hard against the frame on the leading edge, I might look the other way and let it go but I hate to start half-assed doing stuff after all the hard work I have put into the bike so far.

All measurements are center to center.

[jrrobertsjr]

1hotz,

I sent you an email to your personal account.

Johnny out.

[jrrobertsjr]

Still on the hunt for an oil tank that will fit these dimensions.

If anyone has on that will fit these measurements (center to center), please let me know.

I haven't heard back from 1hotz but I am still hoping he has something that will work.

I see a bunch on eBay but no easy way to get any valid measurements from most of the sellers.

I've done my best to get these as accurate as can but if you have questions, PM me with a number and I'll be glad (eager) to call you.

I am not looking for anything for free other than some of your time and a little measuring.

Thanks,

Johnny

[jrrobertsjr]

No pressure from me, bro.

I am just really glad to have you checking on those tanks for me at all.

Gimme a shout when you get a chance and let me know what you need from the parts bin here.

I got a good bit of stuff I won't be using.

Johnny out.

Congrats on the job. I start my new one in 3 weeks and I am already feeling the pressure.