BX24 RPM vs. Speed

[kchear1]

Does anyone notice any difference in speed from 3/4 throttle to wide open throttle?

 

[Matt_Jr]

Yes, but not much. Maybe one or two mph.

 

[kchear1]

Matt,
Thanks for the feedback...It was interesting that it didn't do that when I first bought it. Guess that has to deal with engine break-in?

 

[Matt_Jr]

I don't know about it having anything to do with break in, but the amount of volume and pressure the hydraulic pump can pump at 3/4 throttle vs wide open throttle. The difference is very small is my guess.

 

[BXpanded]

With a positive displacement pump, flow should be exactly in ratio with speed. 3,000 rpm pumps twice as much as 1,500 rpm.

 

[Matt_Jr]

I understand that in theory, but due to fluid dynamics wouldn't the pump lose efficiency at higher RPM's? That and the fact that the pressure relief valve is close to reaching it's point of relief. Is this correct?

 

[kchear1]

Yes, the difference in speed from 3/4 throttle to full is very small...like you said, 1-2 mph, in relationship to the difference as you are going up to 3/4 throttle. There's not a linear relationship, but it is noticeable. Thanks for all the feedback.

 

[johnny_law]

I checked mine yesterday and it may be different than everybody's. Mine revs at about 3000rpm at 3/4 and will rev to 3500-3550 at full. I believe the engine is rated at 3200rpm and I am usually using it in the 2000's or idle.

 

[MPHarper]

I've noticed that my BX2350 is slower now than it used to be regradless of teh RPM. Any idea why?

 

[kchear1]

Mine used to max out speed at 3/4 rpm, but now I run it WOT to get top speed. Regional service rep stated that's how Kubota runs it so as to not strain the engine, especially when running the fel. But even at WOT, it is not as fast as when I first bought it and after about 4 hours of running it WOT, speed drops about 0.5-1 mph.