(I was going down the highway the other day and a guy cutting a yard passed me on one of them.)
Wow, they must be fast!
They droped off my woods M2050 sat. morning and so far I like it. It reminds me of mowing while sitting in a lazyboy. I looked at the exmark lazer Zhp and liked the compactness of it a little better but my new holland dealer gave me a better price and I already know the service to expect from them
OK, I give up. Why are they faster? I have a JD 345 and can mow sucessfully at about 4.5mph with medium to high grass.
I've asked this question on other sites and never got a reliable answer as to why the ztr's can mow up to 10mph with no loss of quality.
Are there blades going around faster?
Do they have more blades?
If its just faster blades then I should be able to gear up my JD and get the same results.
normally 60 inch ztr have three blades of some substance, the max. tip speed of the blade is regulated by OSHA. some of the other reasons are: the decks location, the drivers location, view and control, supension. everything is geared toward mowing quality and speed. the price for a good mower is between 8-14 thousand dollars.
In my opion, it's all in the deck design. I have a 1996 Exmark Turf Ranger with the 60" deck. I can mow at top speed (6.4MPH) without any degradation in cut quality. Yes. I do have to slow down a bit in super thick stuff but not as much as I you'd think.
Exmark (and any Commercial grade ZTR mfg.), first and foremost focuses on their deck designs because the sole purpose of these machines is to cut great and to cut fast. Example: Exmark's top of the line LaserZ XP can mow up to 7 acres per hour. I'm sorry, but that would probably make me dizzy.
The theoretical limit on my Turf Ranger is about 3.64 acres per hour at 100 percent efficiency but a more realistic 2.91 acres per hour can be expected (80% efficiency - allowing for turns and overlapping). This is still quite respectable.
(Please Note: I'm not a lawncare professional, just happen to own a commercial unit which makes mowing akin to an amusement park ride on my less than desirable lawn).
Why a better cut at speed?
From what I've seen, the cutting blades feature a much longer sharpened cutting surface than what is typically found on your typical MMM. The deck is a floating design with four point suspension (Floating action is front to back and side to side) which enables the deck to follow various contours.
The deck also has flow control baffles that improve the quality of cut and no-clog discharge etc. etc. blah blah blah you get the point.
Not sure on the blade tip speed, but suffice to say it must be fairly fast (sounds like a turbo prop). The blade tips on Exmark's mulching deck reach 18,500 fpm.
My Exmark delivers a smoother ride than what my Ingersoll or John Deere did. This may be due to the oversized tires,
seat, and wheelbase. The overall comfort level may contribute to faster mowing speeds as well?
I have no experience with Simplicity or kubota non-ZTR decks, but I've heard numerous comments favoring their cut quality over others. My Ingersoll RM44 deck gave a decent cut, but I couldn't mow as fast with it as I do with my Exmark.
I hope that helped
I don't buy it. Lets set this up again.
Golf course fairway. Level, no bumps no turns. Grass is 5 inches high and we are going to cut it to 3 inches.
Me and my JD are still going to mow this at 4.5mph and get a quality cut.
The ztr is going to mow this at 10mph and get a quality cut.
No problem with suspension, no problem seeing where we're going, same 60 inch deck same 3 heavy duty blades.
There has to be some other reason besides the deck being in front that allows the ztr to more than double my performance.
Do the feds restrict blade speed on ztr's as they do on regular riding lawn tractors? There is some question that is going unanswered here.
Sorry I wasn't of any help. I too suspect that the blade's on commercial mowers spin quite a bit faster than on non commercial mowers. I have no way to validate this, other than audible cues and the speed in which the grass exits the deck.
I think you've underestimated the difference in blade/deck design as well. John deere makes a very nice deck, but even their commercial decks are different than their residential. IMO - It's difficult to make an apples to apples comparison between commercial and residential deck designs within any make?
The combination of more cutting surfaces and higher rotational speeds seems to be a reasonable explanation as to how you can get a faster quality cut.
I don't have my brochures with me here at work, but when I was shopping for a ZTR, one of the main things I looked at was blade-tip speed. The higher the speed, the faster you can mow. I can't remember if the speeds are in fpm or fps, but anyway, my old YardMan tractor spun at about 8,000 and my ZTR goes over 12,000. Heres another point that may contradict what others have said. My ZTR (Gravely) and the others I've seen all have one thing in common. They have "hanging decks". The mower deck is suspended from the middle of the machine at four points and does not touch the ground. Gauge wheels and rollers are set an inch or two above the cut height and only serve to bump-up the deck if an uneven spot or obstruction is hit. This is how I can zoom along at high speed on my bumpy lawn and still get a reasonable cut. My old John deere 650 tractor had a ground contouring deck that rode on four wheels and followed the shape of the turf. I got a more sculpted look, but if I tried to go fast the deck would jump all over and I feared it would disintegrate. Oh yeah, the fastest ZTR's usually have a larger engine per inch of cutting width. My ZTR has 25hp for a 60inch deck. Some ZTR's like SCAGG have much bigger motors for the same size deck and can go two to four mph faster than my 9mph machine.
I have a ransomes bobcat ZTR and it is great. It has 25 hp and no troubles in 3 years of ownership. I mow a 5 acre spot at our mobile home park and I also mow our 3 acres at home.
It is a little rough but very dependable.
When I purchased my ZTR I was told that the blades run about 2.5 times faster than a residential mower because commercial mowers are not regulated like residential mower. I believe this because I also own a residential mower that is just not a fast cutting mower unless you want a bad job.