The CB1100 Community Forum

And they look even better with the four-into-four Wyvern silences!

Agreed.

(09-27-2020, 05:18 PM)Bazbro_imp Wrote: [ -> ]And they look even better with the four-into-four Wyvern silences!

A question, guys..

Can a CB1100 engine be run with fuel supplied only by gravity, or MUST the fuel pump be connected?

The reason I ask is that I have identified a source of CB1100-fit fuel tanks that are look-alike CB750, with gravity fuel taps. The kicker is that they are £75 (unpainted) compared to Samurider's Whitehouse ones, at £1,600 (unpainted)!!

I'll check the Workshop Manual tomorrow to see if I can elucidate any info there, but I thought I'd ask you more knowledgeable guys first.

So if the CB1100 engine will happy run WITHOUT the fuel pump, I could be onto something...

(09-28-2020, 06:24 AM)Bazbro_imp Wrote: [ -> ]A question, guys..

Can a CB1100 engine be run with fuel supplied only by gravity, or MUST the fuel pump be connected?

The reason I ask is that I have identified a source of CB1100-fit fuel tanks that are look-alike CB750, with gravity fuel taps. The kicker is that they are £75 (unpainted) compared to Samurider's Whitehouse ones, at £1,600 (unpainted)!!

I'll check the Workshop Manual tomorrow to see if I can elucidate any info there, but I thought I'd ask you more knowledgeable guys first.

So if the CB1100 engine will happy run WITHOUT the fuel pump, I could be onto something...

Sorry Barry, the answer is no.

The CB1100 is a fuel injected engine which requires a constant fuel pressure of around 50psi at idle (under vacuum), rising to ~57psi at full throttle.

That said, the engine does not need to use the original in-tank fuel pump, you could use an external pump as long as it delivered the same pressure.
I should have also mentioned that the in-tank fuel pump incorporates a fuel pressure regulator, hence the external pump would have to be internally regulated or use an in-line regulator on the supply line.

(09-28-2020, 06:32 AM)Ninemeister_imp Wrote: [ -> ]

(09-28-2020, 06:24 AM)Bazbro_imp Wrote: [ -> ]A question, guys..

Can a CB1100 engine be run with fuel supplied only by gravity, or MUST the fuel pump be connected?

The reason I ask is that I have identified a source of CB1100-fit fuel tanks that are look-alike CB750, with gravity fuel taps. The kicker is that they are £75 (unpainted) compared to Samurider's Whitehouse ones, at £1,600 (unpainted)!!

I'll check the Workshop Manual tomorrow to see if I can elucidate any info there, but I thought I'd ask you more knowledgeable guys first.

So if the CB1100 engine will happy run WITHOUT the fuel pump, I could be onto something...

Sorry Barry, the answer is no.

The CB1100 is a fuel injected engine which requires a constant fuel pressure of around 50psi at idle (under vacuum), rising to ~57psi at full throttle.

That said, the engine does not need to use the original in-tank fuel pump, you could use an external pump as long as it delivered the same pressure.
I should have also mentioned that the in-tank fuel pump incorporates a fuel pressure regulator, hence the external pump would have to be internally regulated or use an in-line regulator on the supply line.

Sorry Barry, the answer is no.

The CB1100 is a fuel injected engine which requires a constant fuel pressure of around 50psi at idle (under vacuum), rising to ~57psi at full throttle.

That said, the engine does not need to use the original in-tank fuel pump, you could use an external pump as long as it delivered the same pressure.
I should have also mentioned that the in-tank fuel pump incorporates a fuel pressure regulator, hence the external pump would have to be internally regulated or use an in-line regulator on the supply line.
Very many thanks, Nine. An added complication but not insurmountable - just more cost and difficulty!

I'll have a look at the Workshop Manual when I get up and see what can be done.

Thanks again.

Darn it! On closely checking the dimensions of this remarkably cheap tank, whilst it has the LOOK of a CB750 tank, it's small - much smaller, just 9 litres! So back to the drawing board.

I've contacted an Indian company, who make excellent reproduction tanks, to ask them about this very question, namely, a 1972 CB750-looking tank that will fit a 2011-2020 CB1100. But don't hold yer breath...

I'll keep everyone posted if I hear anything. Meanwhile, I await Ninemeister's write-up on his K10/17. Happy days!

(09-28-2020, 07:10 PM)Bazbro_imp Wrote: [ -> ]Darn it! On closely checking the dimensions of this remarkably cheap tank, whilst it has the LOOK of a CB750 tank, it's small - much smaller, just 9 litres! So back to the drawing board.

I've contacted an Indian company, who make excellent reproduction tanks, to ask them about this very question, namely, a 1972 CB750-looking tank that will fit a 2011-2020 CB1100. But don't hold yer breath...

I'll keep everyone posted if I hear anything. Meanwhile, I await Ninemeister's write-up on his K10/17. Happy days!

Funny you mention Indian tanks. I'm going to buy an aluminium tank for my BMW Cafe project and have talked to a couple of companies out there who can make me a tank for around £400-£500.
I'm sure if you sent a stock CB11 tank the same guys could either re-fashion it into a very passable (but larger) CB750 unit or make you a new one in alloy?

(09-28-2020, 11:50 PM)Ninemeister_imp Wrote: [ -> ]

(09-28-2020, 07:10 PM)Bazbro_imp Wrote: [ -> ]Darn it! On closely checking the dimensions of this remarkably cheap tank, whilst it has the LOOK of a CB750 tank, it's small - much smaller, just 9 litres! So back to the drawing board.

I've contacted an Indian company, who make excellent reproduction tanks, to ask them about this very question, namely, a 1972 CB750-looking tank that will fit a 2011-2020 CB1100. But don't hold yer breath...

I'll keep everyone posted if I hear anything. Meanwhile, I await Ninemeister's write-up on his K10/17. Happy days!

Funny you mention Indian tanks. I'm going to buy an aluminium tank for my BMW Cafe project and have talked to a couple of companies out there who can make me a tank for around £400-£500.
I'm sure if you sent a stock CB11 tank the same guys could either re-fashion it into a very passable (but larger) CB750 unit or make you a new one in alloy?

Funny you mention Indian tanks. I'm going to buy an aluminium tank for my BMW Cafe project and have talked to a couple of companies out there who can make me a tank for around £400-£500.
I'm sure if you sent a stock CB11 tank the same guys could either re-fashion it into a very passable (but larger) CB750 unit or make you a new one in alloy?
That's the EXACT conversations that I've had with my Indian contact ('Bikenation'), funnily enough. He suggested that I send him a tank for him to fashion into what I suggest, but I've pointed out to him that, as far as I can tell, they would need TWO tanks - a CB750K2 to form the outer, visible shell, and a CB1100EX/RS bottom part to weld underneath. And as I'm not made of money (otherwise I'd buy the Whitehouse one I've been telling him about!!) I just cannot buy TWO tanks, plus their postage to India! I'll see if he comes back to me with anything.

An alloy replica CB750 tank has ENORMOUS appeal...!!

There is a company in your neighborhood making beautiful alu tanks for bikes , they make them for Gold Stars etc.