What is the quietest rotary motor mower ?

Bam

Forum Newbie
Joined
Jul 1, 2011
Threads
1
Messages
6
I want to buy a new small rotary motor mower of about 18 to 24 inch cut. Grass box not essential as I mulch mow.

But I want a quiet one. Years ago, the long stroke mowers reved slower and were quieter. One modern one I can hear from 1/4 mile away is a Honda, which put me off that make.

I have never seen the noise of mowers compared but they all seem to have a decibel label attached.

Sometimes it is not so much the volume of noise but the frequency. A low pitch mower is more tolerable than a high pitched one. Is there a special specification for mowers used around Hospitals etc?

Does anyone know of a particularly quiet model? I prefer 4 stroke.

I am in the UK.
 

jmurray01

, , 1,000 Post Club
Joined
Apr 7, 2011
Threads
129
Messages
1,490
Ah, in the UK. Well this makes things easier!

I own a Mountfield SP414 (On sale in B&Q for 」159.99), which has a sticker on it saying it produces 96DB noise levels, however it isn't a high pitched engine.

It is a bit like a V8 kind of sound actually :laughing:

The Mountfield SP414 also leaves the grass looking like it has been mowed with a cylinder mower, so I've got no complaints on the quality of the lawn. The body is polypropylene which means it won't rust, neither will it crack. The engine is a 100CC RS100 engine, made by Mountfield, which starts on the first pull after three primes of the bulb, and runs nice and smooth.
 

KennyV

Lawn Pro
Joined
May 5, 2010
Threads
26
Messages
5,447
You will always have the engine noise with an internal combustion engine. Some makes use a better muffler system than others...
The type of grass you cut can have an impact, If you do not need a high lift blade, you can use one that is closer to flat... the less pitch a blade has the quieter it will run...

Also if you keep the blades very sharp you can reduce the engine RPM & that will have an impact on sound levels... :smile:KennyV
 

jmurray01

, , 1,000 Post Club
Joined
Apr 7, 2011
Threads
129
Messages
1,490
You will always have the engine noise with an internal combustion engine. Some makes use a better muffler system than others...
The type of grass you cut can have an impact, If you do not need a high lift blade, you can use one that is closer to flat... the less pitch a blade has the quieter it will run...

Also if you keep the blades very sharp you can reduce the engine RPM & that will have an impact on sound levels... :smile:KennyV
That is very true, but new engines don't have throttles, so that wouldn't matter :frown:
 

KennyV

Lawn Pro
Joined
May 5, 2010
Threads
26
Messages
5,447
That is very true, but new engines don't have throttles, so that wouldn't matter :frown:
I did not realize you didn't have them... The only fixed rpm engines over here are usually found on generators, and even they have the ability to change the rpm...

Well I guess I should say... The engines I am aware over here, all have variable throttles....

So your mowers are either running "full on" or they are OFF. That's very interesting... :smile:KennyV
 

Black Bart

Well-Known Member
Joined
May 4, 2011
Threads
15
Messages
550
Several push mowers don't have a throttle but I don't think I ever saw a riding mower without a throttle.
 

KennyV

Lawn Pro
Joined
May 5, 2010
Threads
26
Messages
5,447
Several push mowers don't have a throttle but I don't think I ever saw a riding mower without a throttle.

I've seen some with no throttle on the handle, near the operator...
But they all had a throttles settable at the carb, allowing you to set the engine speed...

I guess I need to get out more & see what is 'not' available any longer... :smile:KennyV
 

BKBrown

Lawn Addict
Joined
May 5, 2010
Threads
15
Messages
1,415
When I see / hear "rotary motor - rotary engine" I think Wankel !

Wondering if "rotary motor" means the same as "vertical shaft" ???

I want to buy a new small rotary motor mower
 

KennyV

Lawn Pro
Joined
May 5, 2010
Threads
26
Messages
5,447
...
...
Wondering if "rotary motor" means the same as "vertical shaft" ???

I think today it most likely is interchangeable, But back in the early 60's or late 50's Snapper had a monster self propelled, commercial grade rotary mower... With a BIG horizontal shaft Wisconsin engine... :smile:KennyV
 

Bam

Forum Newbie
Joined
Jul 1, 2011
Threads
1
Messages
6
Thanks for your responses. I did not expect to get such a quick reply. This is a great forum. The Mountfield mower sounds a good buy but I think I would be looking for a larger size if they do one. I am starting to feel a bit of old age and the smallest budget mower I have now takes an age to do my grass which is quite a large area for a push along mower but has too many nooks and crannies for a ride on and anyway I need the workout !

I am wondering if a dedicated mulch mower might be the quieter option because they do not have to generate a "vacuum cleaner" fan effect to blow the grass into a box .

I think I am safe in saying that Mountfield do not make engines although their name may be on them. Probably use a Chinese engine or from Poland or some such place.

I was always keen on the Briggs and Stratton sidevalve motors ( flathead to you Yanks). They had a slow reving engine which sounded nice and had a lot of torque ( ie difficult to stall ) and they would outlast the rest of the mower. However, they now use a shorter stroke engine, which has to rev more for the same power and they have devised a troublesome carburettor set up. The last two engines were OK new but after a couple of years developed the same fault of reving faster and faster when they get hot and there is no problem with the govenor mechanism. This also causes them to gobble fuel (very expensive in the UK). I think it maybe that they use a horrible membrane type carb.

Someone mentioned the Wankel engine and a V8 but I only want to cut grass not go mower racing :laughing:
 
Top