Topic: CR750 Oil tank

[froj]

Hello ,

as part of the preparation of the K6, is it possible to find the plan or dimensions of the oil tank of the CR750?

This plan can be modeled in 3D by a friend and made available to the forum 

[gschuld]

I can’t help with the info but that would be nice?

George

[froj]

I can’t help with the info but that would be nice?

George

Thank you George,

CR parts are particularly "rare" and expensive.
The idea is to be able with plans and dimensions to model them in 3D in order to benefit everyone.

It takes work but the informatic  tools are powerful :-)

Froj

[gschuld]

I agree.  I’d be particularly interested in a 3d model of the correct cr750 fuel tank as well😉

George.

[H2Eric]

Fuel tanks I believe came in two sizes 28 litre and 22 litre unless someone knows different.
Oil tanks also came in two different styles, those with a flat side facing forwards and those with a bulge for extra oil capacity, which I think were used on some of the endurance racers. They also used the standard Honda filler cap as opposed to the Monza style.

Eric

[napoleonb]

17500-300-970   Tank comp., fuel   1   replaces 17500-300-020   Aluminium fuel tank (capacity 28 liters)
17600-300-970   Tank comp., fuel   1   22 liters
55100-300-970   Tank comp., oil   1

There is no mention of the bulged oil tank in my 3 different parts lists, but I did see some on original photo's.
Also the 22 liter tank had the same tank cap as the standard CB's if memory serves me correctly, it doesn't specify if the tank is made out of aluminium or steel.

[froj]

Thank you Eric, Napoleonb

For this information but I am looking for a plan or photos with dimensions.
But, I'm talking about the oil tank and not the fuel tank ...

cordially

Froj

[napoleonb]

I understand, but the rational behind my post is that I've found no evidence of a later kit version specifically designed for enduroracing and for sale to the general public even as late as 1974 from the CB750-K5 kit partslist. There are a lot of replica's around and most are claimed to be made from an original tank but they do differ a lot between them.
So I recon you're not likely to be able to find one from an original bike and borrow it for a while to model it in 3D, if you do it'll be great off course and I for one am interested!

Most oil tanks are made so you can use the standard oil line between the tank and engine, each partskit had a specific part listed whereas standard parts were used just as much.
So there is what I think is the main reason for all those different tanks, it would be nice to source 15510-300-970 Hose comp., oil, A for reference.
I ended up just making my own from pictures as close as I could.

[Old Scrambler]

I measured and photographed CR replica oil tanks and then produced two units (both sold).
We improved the tanks with inner baffles and wrench-bungs to fasten the oil-lines without stressing the tanks.
We could make another. I have seen photos of units with a recessed curve on rear panel. Was this used on the 1970 CRs?

[froj]

I measured and photographed CR replica oil tanks and then produced two units (both sold).
We improved the tanks with inner baffles and wrench-bungs to fasten the oil-lines without stressing the tanks.
We could make another. I have seen photos of units with a recessed curve on rear panel. Was this used on the 1970 CRs?

Thank you for your answer,

Could you tell me the dimensions that you could measure?

The idea as I said in my first post is to model it and print it in 3D.

cordially

Froj

[westfieldandy]

I just read this,  a bit late but, for info:-

we spent 3 years racing a cr, and developed and tested loads of stuff to make a cr competitive.   one of the biggest problems is heat, the oil cooler too small and the oil tank needs to be as big as poss.    after developing as bigger oil tank as poss and re-working engine internals we began to manage heat.

then having looked through archives etc you can see honda had the same problems,  the later bikes after the dick mann win you can see all sorts of different idea's on privately run cr's, I then came across some of the honda france enduance bikes and the peter darvill bikes, and they all looked to be trying bigger tanks and coolers.   more compression = more heat.

So the stock tank was obviously not big enough, try and develop something along the same shape but with more capacity if your going racing.

[RottenRalph]

No dimensions but an auction website had some amazing shots of Vic World's '970' bike with some great close-ups, if Vic is on this forum I hope he doesn't mind me posting them. Ive got these printed off on my bedroom wall - p*rnhub not needed!

[Sam Green Racing]

I just read this,  a bit late but, for info:-

we spent 3 years racing a cr, and developed and tested loads of stuff to make a cr competitive.   one of the biggest problems is heat, the oil cooler too small and the oil tank needs to be as big as poss.    after developing as bigger oil tank as poss and re-working engine internals we began to manage heat.

then having looked through archives etc you can see honda had the same problems,  the later bikes after the dick mann win you can see all sorts of different idea's on privately run cr's, I then came across some of the honda france enduance bikes and the peter darvill bikes, and they all looked to be trying bigger tanks and coolers.   more compression = more heat.

So the stock tank was obviously not big enough, try and develop something along the same shape but with more capacity if your going racing.

Hi Andy, nice to see you are still about and showing an interest. Although a good idea, I don't know if Froj realizes what he is up against.
Different oil tanks have come and gone and copies made from them, some claiming to be made from original's, if he does get to make one, will there be just another look alike tank out there.
Honda have a bike on show in their museum, claiming to be the actual Dick Mann bike that won Daytona in 1970, it might be the bike but the fairing is not the one that Dick crossed the finish line with. If Honda can't get it period correct, what chance have others got when claiming something is a copy of an original. hahaha, Have fun guys and a happy Easter to you all.

Sam