Mowing How fast should you mow?

W00dman · May 20, 2010

I am the new owner of a Douglas 72" finish mower that I am using with my Jinma 284 tractor. The PTO speed is set at 540 but I am not sure what RPM's, gear and speed I should be running. Obviously if the speed is too fast the cut will be rough and if too slow you will be waisting time and gas etc. but I am more concerned with damage to the tractor or the mower. Will the PTO speed always be a maximum speed of 540 regardless of the speed of the tractor?
I would appreciate any helpful feedback as I am a city guy wanting to try to live in the country.

greg_g · May 20, 2010

Damage potential to either the tractor or the mower is negligible, because the deck is belt-driven. Before anything serious happens to either, the deck belt(s) usually go first. Having said that, you should walk an unknown piece of ground to make sure there are no immovable objects (posts/stumps/rocks/etc) that could substantially shorten the life of a blade or two.

Always keep the throttle where you're producing 540 rpm at the PTO. After that, use the quality of cut to determine which range and gear needed to control ground speed. I think you have a dual range 3 speed. I know for a fact that H2 and H3 are way too fast. You might be able to mow in H1, but more likely in L3

//greg//

beenthere · May 20, 2010

How fast would be limited to your seat and body, and the cut you are happy with. I'd think the equipment will take whatever beating you can take.

Diamondpilot · May 20, 2010

I just got in from 2 hours of seat time on my Jinma 254, same tractor as your 284, mowing with my 72" Caroni Finish Mower. I have mowed in H1 for 7 years and have had no issues.

I set the hand throttle right at the green line on the tach. I think its 2200 rpm or so. That allows you to achive 540 rpm on the pto. My tractor uses about 3/4 of a gallon of fuel per hour at this setting and cuts great. I can mow about 2 acres a hour easily at this speed.

Chris

IslandTractor · May 20, 2010

Depends on what you are trying to mow. If you are mowing a finish lawn then you'll get the best cut at PTO speed and moving at a modest speed. If you are just trying to knock down grass in a field then 10-20% under PTO and a comfortable speed will get the job done.

I use a flail but only run at PTO (about 2500rpm) when the grass is really tall and green like at the end of June. The rest of the summer I cut back to about 2100. Much less noisy and gets the job done.

ray66v · May 20, 2010

I have a unique perspective on this question, as my mower actually has a speedometer on it.

Most of the time I mow at 4 mph.

I do occasionally mow between 4 and 7 mph, depending on how high the grass is, and how big a hurry I am in.

beenthere · May 20, 2010

W00dman said:
........ Will the PTO speed always be a maximum speed of 540 regardless of the speed of the tractor?.............

PTO speed is independent of the ground speed (normally), and only dependent on the rpm of the tractor engine. 540 is just a recommended speed for attachments. I usually don't run my attachments at 540 PTO speed, if the job is done well at lower rpm.

I consistently mow 5 acres of lawn, at about 2+ acres an hour. That is with JD AWS lawn tractors.