What RPM do you mow at?

[JDgreen]

This should apply only to those who have an engine where you can vary the operating speed, it does not apply to mowers that run at a set, constant speed.

Every mower or tractor I have owned that had a throttle that controlled engine speed clearly stated in the manual "always mow at full engine speed", but many times if I was mowing dry grass or grass that wasn't hard to cut, I never used more than 80% of throttle. Supposedly using 80% of throttle gives the engine a workout (especially important in a small diesel) but doesn't stress the engine enough to cause problems down the road. I posted the same query on TractorbyNet several years ago and the responses were mostly "run at 80% maximum throttle when you can and save the remainder for an ugly day" :laughing::confused2: which I interpret as meaning when you have to cut fast to get ahead of the rain that is coming give it full throttle. Any thoughts?

 

[indypower]

I always run at full throttle. These engines are made to run at full throttle and run best there.

 

[Kingwood990]

I run my John Deere at full throttle.
I have had zero problems doing so and also the hydrostatic transmissions on these and other machines need the higher rpms to keep the transmission cooling fan working at maximum efficiency.

 

[grnspot110]

They are also designed to cool best at full throttle!

 

[lizard]

Diesels of today can run at idle or full governed RPM.......it will not hurt the engine......so Please do not Worry........just make sure you service the Engine every 200 Hours.:confused2:

 

[jenkinsph]

I mow at full throttle most of the time, I will slow down some if doing alot of trimming in close quarters. I don't think it matters much if you keep the rpm's up most of the time, idling excessively can cause problems though.

 

[KennyV]

My tractor and tractor type mowers have tachometers with PTO speed marked... and that is generally just a bit less than WOT... probably around 80%...
My mowers and decks have blade tip speed listings and I generally try to find the rpm that achieves the blade tip speed... Faster gets a better cut generally & is less load on everything... but I have never seen it necessary to run any engine at it's maximum RPM... the governor is usually going to allow a top RPM of just a little more than you have to run at... :smile:KennyV

 

[jenkinsph]

My tractor and tractor type mowers have tachometers with PTO speed marked... and that is generally just a bit less than WOT... probably around 80%...
My mowers and decks have blade tip speed listings and I generally try to find the rpm that achieves the blade tip speed... Faster gets a better cut generally & is less load on everything... but I have never seen it necessary to run any engine at it's maximum RPM... the governor is usually going to allow a top RPM of just a little more than you have to run at... :smile:KennyV

Well Kenny my older tractors have the tachs with pto speed marked as you mentioned. My newest tractor has the epto option which allows 540 rpm at a reduced engine speed of 1740 rpm. This works well for an MX6 brush cutter in most cases. If I have to cut something really heavy I use the regular setting. When brush cutting I can run much lower as I am not concerned about high tip speeds and fine cuts. The 4520 with ehydro and upgraded cruise, digital tach and speedometer does add some nice features. But I digress, I thought this was a lawnmower forum.

 

[KennyV]

I thought this was a lawnmower forum.

It is a Lawn Mower Forum...:thumbsup:
But the original question is "What RPM do you mow at?":biggrin:

I mow with a Kubota Grand L tractor... with a 7 foot finish mower & a 6 foot rotary mower... and a Large ZTR mower... all of which have tachometers and recommended blade tip speeds...
My smaller tractors without PTO indicators leave me running just a bit lower than max engine governor speed... :smile:KennyV

 

[173abn]

my grasshopper[kubota diesel] the manual states the no load rpm is 3000 and the pto is 3100max.it doesn't have a tach. but does have an hour meter.I usually run it at 3/4 throttle. when I used to mow with my Yanmar w/finish mower it was 2200rpm. russ