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My 60 idles at 400. Full tilt is 1100 RPM. Pretty crazy when you think about it. 321 cubic inches. Two coffee can cylinders with cast iron pistons with somewhere around 5 or 6:1 compression ratio running at these speeds compared to a modern machine.
 

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Discussion Starter · #22 ·
tractors and implements were designed to be run at certain RPM's just do it.
But why? If lower rpm does the some jobs activates the passive regen and lastly if feels like its more fuel efficient. I will hopefully confirm that one when TractorPlus adapter finally arrives.
And I definitely do not believe that tractor and implements are designed just to work properly at one single rpm. Spare the generator that was mentioned.
As I said we have few implemets that are designed to work at 540 but especially state that there is no need for that high of a rpm for them to work properly and as intended.
 

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But why? If lower rpm does the some jobs activates the passive regen and lastly if feels like its more fuel efficient. I will hopefully confirm that one when TractorPlus adapter finally arrives.
And I definitely do not believe that tractor and implements are designed just to work properly at one single rpm. Spare the generator that was mentioned.
As I said we have few implemets that are designed to work at 540 but especially state that there is no need for that high of a rpm for them to work properly and as intended.

mowers, blade tip speed for nice cut
tillers, tine speed for grinding dirt fine
Engineers did not randomly pick numbers to put on implements, there is good reason behind them. We may not understand why but there is.
Also it has to do with fluid flow in the hydrostatic pumps on the tractor itself. It is not good to run them slower and reduce oil flow.
This is another area that can be beat to death for everyone that successfully follows the directions there is one that does not and never has an issue. Is it extremely important probably not.
I bought a Monza 2+2 4 cylinder back in the 70's. I NEVER put new oil in that engine, I used the oil I drained from my tow truck. That car ran like a watch up until, 285,000 miles, when I hit a curb in an ice storm and bent the unibody. So is new oil really all that important ?
this is another case of IMO
just because you can don't mean you should.
 

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I definitely did not notice any difference in cut either with flail mower or disc mower. In heavy or normal grass. We have brush hog but currently its out of commission. But I definitely ran it at 450rpm and there was not anything to complain about with final cut. (There was later but because blade was as sharp as a ball.) For me it feels like tip speed is only important when lawn quality cutting is required so just finish mowers.
Our gas Z545R I run at wide open quite often but linear power increase typical for gas engines is really noticeable on that one.
I do notice a reduction is cut quality using a drum mower in heavy material if I don't run right up at speed. The drum mower, like a disc mower relies on very short blades pivoting on an axis and if the speed isn't fast enough the blades will not cut full width. Normally I can run a little under PTO speed but not in heavy material.

The other time that PTO speed really matters is with our tedder. I don't necessarily run at 540 PTO but match pto speed to the material to get the spread I want. That may be as low as 400 pto or it might be right up at 540, it just depends on the material.

I don't like running a 540 implement over 540. I'm sure they can take a little overspeed but prefer to not find out.
 
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Discussion Starter · #25 ·
I do notice a reduction is cut quality using a drum mower in heavy material if I don't run right up at speed. The drum mower, like a disc mower relies on very short blades pivoting on an axis and if the speed isn't fast enough the blades will not cut full width. Normally I can run a little under PTO speed but not in heavy material.

The other time that PTO speed really matters is with our tedder. I don't necessarily run at 540 PTO but match pto speed to the material to get the spread I want. That may be as low as 400 pto or it might be right up at 540, it just depends on the material.

I don't like running a 540 implement over 540. I'm sure they can take a little overspeed but prefer to not find out.
Now that is interesting as our tedder is one of the implements that wants relatively slow rpms and manual says that it is not advisable to run at 540 as it wont work properly. I guess either different tedding mechanism or gearing then.
Using our disc mower and before drum mower (basically the same) I never noticed any difference in cut quality or capacity. What most affected capacity was speed. But I could not go any faster even with higher rpms without bogging down to the same rpm.
 

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Discussion Starter · #26 ·
mowers, blade tip speed for nice cut
tillers, tine speed for grinding dirt fine
Engineers did not randomly pick numbers to put on implements, there is good reason behind them. We may not understand why but there is.
Also it has to do with fluid flow in the hydrostatic pumps on the tractor itself. It is not good to run them slower and reduce oil flow.
This is another area that can be beat to death for everyone that successfully follows the directions there is one that does not and never has an issue. Is it extremely important probably not.
I bought a Monza 2+2 4 cylinder back in the 70's. I NEVER put new oil in that engine, I used the oil I drained from my tow truck. That car ran like a watch up until, 285,000 miles, when I hit a curb in an ice storm and bent the unibody. So is new oil really all that important ?
this is another case of IMO
just because you can don't mean you should.
I agree with finish mowers or any other lawn mower to achieve nicer final look. But I did not notice anything with a tiller. The difference that tractor speed and especially rear chute made was significantly more noticable. Difference that pto rpm was not discernable in person or on the close-up pictures I took for comparison.
JD technicians also did hyd. flow testing and from ~2000 to wot there was only tiny marginal increase in flow.
In the first place it was them who instructed me not to use wot unless absolutely necessary with howering between 2-2.5k being the ideal for this tractor and engine.
Engineers pick numbers in transmissions of the implements as 540/1000 are standards for rear PTO I do not think there are actually many implements that run specifically at those rpms.
 

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Now that is interesting as our tedder is one of the implements that wants relatively slow rpms and manual says that it is not advisable to run at 540 as it wont work properly. I guess either different tedding mechanism or gearing then.
Using our disc mower and before drum mower (basically the same) I never noticed any difference in cut quality or capacity. What most affected capacity was speed. But I could not go any faster even with higher rpms without bogging down to the same rpm.
I don't usually run the tedder at 540 but on occasion, the material needed to be run fast to spread properly. I'll usually start slower and watch as I speed up the rpms until I get the ground speed/rpm combo that gives a nice even spread.

Your right on ground speed on the mowers. You can overload them by going too fast. Unfortunately, it's hard to see uncut material until you rake when the whole world can see your error. It's a bit like spraying used to be before guidance. Miss a streak and see it until the crop is harvested, lol.
 
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