GS110X - Oil pump 1100/750

[SMARTY]

Hi, just want to find out if the 750 and 1100 oil pumps are the same, and what is the story round putting 750 pump gears in- is it for better volume?

[wraith]

The gsx750et have a higher volume gears than the gsx1100et, they also fit the gs850/1000 not 100% on the 750 and don't know if they will fit the efe

[Gixer1460]

1 hour ago, wraith said:

The gsx750et have a higher volume gears than the gsx1100et, they also fit the gs850/1000 not 100% on the 750 and don't know if they will fit the efe

I was told the gear swap was from the GS750/550 not the GSX variant? The GSX750ET definately had a different oil supply as oil pressure was considerably greater as required for the shell bearings in the mains and rods. The gears when used in the 1100's never produce anything like the pressure got in the 750ET for some strange reason even though I think the pumps are the same! With the uprated gears in a 1100/1150 you nearly double the std. pressure to a 'huge' max of about 30psi LOL!

[wraith]

I've used the 750et gears in GS 850 and 1000 many times with good results.

Just read that people have used them in the 1100 and had a mate that used the 750et gears in his 1100/1170 et 

But that's what he said 

[SMARTY]

Thanks, cheers

[Jonny]

I have GS750 oil pump gears in my EFE motor if that helps.

[Pedda]

Using 750 oil pump gears on the big engines gives higher oil flow by different ratio.
1100 ccm engines have 33 : 34 teeth
750 ccm engines have 29 : 38 teeth

the pump is the same. Changing the gears is a straight swap.

[johnr]

On 5/26/2023 at 9:32 PM, Gixer1460 said:

I was told the gear swap was from the GS750/550 not the GSX variant? The GSX750ET definately had a different oil supply as oil pressure was considerably greater as required for the shell bearings in the mains and rods. The gears when used in the 1100's never produce anything like the pressure got in the 750ET for some strange reason even though I think the pumps are the same! With the uprated gears in a 1100/1150 you nearly double the std. pressure to a 'huge' max of about 30psi LOL!

750 had higher oil pressure because it had a shell crank so the pump was pushing the oil against something trying to squeeze it in between those plain bearings. 1100 roller crank just needed the oil to be there in order to keep its balls wet......

[Tony Nitrous]

Just thinking out loud..
 

When you play mix and match with the gears to increase pressure, is there a pressure relief valve that limits it ?  Obviously you benefit from running max valve pressure and more flow but is there a valve that limits gains if left untouched  ?

[Arttu]

No, there is no pressure relief valve on the roller bearing GS/GSX engines. And don't worry, you won't need it with 750 pump gears. Even with them the oil pressure will be only around 0.5 bar (7 psi) when the oil is hot. With cold oil it may get up to 2 bar or so but even that isn't anything to worry about.

[imago]

4 hours ago, Tony Nitrous said:

Just thinking out loud..
 

When you play mix and match with the gears to increase pressure, is there a pressure relief valve that limits it ?  Obviously you benefit from running max valve pressure and more flow but is there a valve that limits gains if left untouched  ?

It's not about the pressure, it's about volume.

The stock set up for an 1100 is fine for lubricating the roller bearings, cams etc. If you tune an engine you put more pressure on the components, that causes more friction which in turn generates more heat. So if you increase the volume of oil flowing through the engine you increase the amount of heat which can be transferred to the oil. If you tune it to a larger degree, increasing the displacement, amount of fuel through etc then you need to look at extracting the heat from the oil quicker so an oil cooler is then next step.

 

[Blower1]

I have  planned to make a new bigger and more efficient oil pump to place where the original pump is now.

Just need to find oil pump rotors, which are a few mm bigger in diameter and taller. Making the pump housing is not difficult.

[johnr]

On 6/12/2023 at 4:42 AM, Tony Nitrous said:

Just thinking out loud..
 

When you play mix and match with the gears to increase pressure, is there a pressure relief valve that limits it ?  Obviously you benefit from running max valve pressure and more flow but is there a valve that limits gains if left untouched  ?

i think you need to forget about the oil in the big gsx being pumped at any significant pressure, youll do well to see 15psi, swapping the pump gear ups the volume that it flows, but its not under any real presure.

 

[SMARTY]

Thanks good explination