Mower deck width for G1900

Hugo Habicht

Member

Equipment
G1900
Jun 24, 2024
57
47
18
Ireland
Hi,

I have a question regarding mower decks. I am thinking of buying a wider deck for my G1900 (18hp). A dealer told me that the rc60 would be too big and would require a tractor with about 30hp. The G1900 was offered with 48, 54 and 60" wide decks. So why would it suddenly be too weak? With the 48" deck I have it even cut 2 feet high grass, just by going very slowly.

Has anybody used a 60" wide deck with a G1900 or similar and seen any problems? It is only 25% wider than he 48".

Kind regards,
Hugo
 

GreensvilleJay

Well-known member

Equipment
BX23-S,57 A-C D-14,58 A-C D-14, 57 A-C D-14,tiller,cults,Millcreek 25G spreader,
Apr 2, 2019
11,169
4,778
113
Greensville,Ontario,Canada
hmm, kinda answered your own question.....
can it be done, 'yes' but....

48" deck you have to go very slowly....
if you put on a 60" deck (25% wider) ... 'very slowly' will become 'very,very,very,very slowly'.PAINFULLY slow !!

The 'math' isn't simple....like 25% wider becomes 25% slower... more likely 75% slower,or more. Worse when grass is damp, far worse when it's wet.

Also a wider deck means wider turns and unless lawn is a putting green, digging in is a reality.
 

Hugo Habicht

Member

Equipment
G1900
Jun 24, 2024
57
47
18
Ireland
Hi,

what you are saying is the mower speed is dependent on deck width which would basically mean with a certain amount of horsepower you need a fixed time for mowing, independent on deck width.

I do not have a clue about those cutting decks but my thinking is that driving speed depends entirely on blade speed for a similar result and this is only dependent on the engine speed. Assuming the engine can handle the power required. Cutting at full speed (8mph) I do not notice any strain on the deck or the engine (weekly cut).

My example of 2 feet high grass was an extreme one, of course, I tried if it could handle that, and it did well, only it requires a long time to chop up all that grass, hence the very low speed.

The digging in is a very valid point although I think my area is level enough and would handle it well.

The deck I have needs a lot of work to bring it back to pristine condition and a dealer is selling off brand new decks for the price of less than two 30 year old deck gear boxes offered on ebay. Strangely enough the 48" is the same price as the 60" decks they are selling, hence my question here.

Kind regards,
Hugo
 

Hugo Habicht

Member

Equipment
G1900
Jun 24, 2024
57
47
18
Ireland
I use a 54" on my G1800 no issues at all.
Ok, so
18hp / 16hp is +12.5% more power available
and
60" / 54" is only +11.1% more power required

Subtracting the constant power required for moving the tractor makes it even better. So the G1900 is well capable for a 60" deck and that is why Kubota offered this configuration originally.

Of course 18hp is not enough to cut through 1 foot high grass at 20 miles an hour but for cutting the lawn weekly it should be fine and will decrease my cutting time by another 25%, even more considering the overlap, which, with my amateur cutting skills is quite substantial :)

Kind regards,
Hugo