Hi 85Hokie... Yes, I understand about lugging an engine, but with my Deere, 1500rpm almost never lugged down... it just did the work with a smooth even engine speed. Running at twice that rpm seems wasteful for fuel, and excessive on engine wear over time... that's a LOT of engine wear over a couple thousand hours of operation. I've also heard on another forum of issues with the Kubota hydros "bypassing" under a load while pushing, or climbing a grade with a full bucket, and the answers given were to back off the throttle and 'crawl' the several minutes it took to get to the top of the grade (not steep according to the questioner)... that doesn't sound attractive to me where with the manual trans I just scooted up ANY grade (shy of tipping over) w/o any added stress to the engine. Has this been YOUR experience with these hydros?
Hard to compare a diesel model vs another "similar" model -
For example - a L2501 I think has a top end at 2200 rpms according to specs ..... why? Probably to keep the HP below the magic threshold without DPF - but a BX can wind out at 3400 rpms. SO two different engines making HP at two different RPMS. SO running a deere at "X" rpms geared and a Kubota HST at "X" leaves way too many variables to have a proper decision to be made on that amount of info. As for running at twice the RPM's - that math cannot compute - again 2 entirely different engines designed by two different manufacturers. AS for fuel consumption, look at this chart of the B7800 engine,
fuel consumption for this engine is the same at 2000 rpms as it is 2800 rpms - and the hp has increased - true torque has gone down, but the engine is running at a rpm to cut or pull or whatever the engine is designed to accomplish.
As for wear on engine, you would be surprised that the LACK of wear on an engine at a rated RPM - whether or not you run your engine at X or Y rpms is completely up to you, but the engine wears the most when you turn your key - period, once it is to temp - the wear is almost none. And as for your information about "bypassing" on a hill - true it does not do well to go uphill in a HIGH range with bucket fully loaded, same thing as moving up that same hill in 4th gear from a standstill on a 4 speed tractor. What you read on the "other" forum is someone that wants their cake and icing and eat it too!!!
Newer machine HAVE to be run at their higher RPM's due to the regen's it must go through.
HST's are designed on either 2 speed or 3 speed DEPENDING on the proper use of the machine - notice I said proper .......... too many people think a BX should be able to pick up the ass end of a truck and sprint around the yard with it in tow!
Information is just that - information, some people will never listen to simple scientific fact, some will buck the system due to a myth that someone else told them.....
The myths about synthetic oils come to mind, sooooo many people BELIEVE that it causes seals to leak or the engine needs to be broken in first then switch...... Neither being true ( a seal leaks because it is bad - and the oil that the synthetic replaced had a higher viscosity than the synthetic)
the reason I bring up that point is this - Kubota along with other diesel manufacturers KNOW how the engine should be run, and they make a manual accordingly. I agree that running an engine wide the hell open for no apparent reason foolish, but it is designed to be run at that RPMS for the life of a engine!
Best point to understand is a diesel generator - there typically is no variables in engine rpm - turn it on and it runs at rated RPM to produce the power needed.
Again - the point made here, run as you see fit, as long as it works for you. And based on information - there are few kubota's I would NOT want to own.
