Traction is not a problem here, four-wheel drive can be selected with a lever on the dash and a difflock is operated on the floor. Equally sized Goodyear AT25x10-12 Tracker Mud Runner tyres all round provide all the grip that is required.
Like many vehicles of this type, and smaller ATVs, they are designed to run at low tyre pressures, 10 to 12psi in this case. Consequently, they tend to be very light on their feet.
At the time of writing, everywhere that we drove on land was extremely wet, yet the Kubota RTV 900 left only a very light impression on the ground even with two WX heavies and a round bale of straw on board. Where the land was a mess, churned up by some geriatric equine hooves, the RTV exceeded my expectations. A tractor would have left some pretty decent scars on the field; the Kubota went out to work and back with just some bruising.
What really sets the Kubota RTV 900 apart from much of the competition is the fact that it uses a hydrostatic transmission to transfer the drive from the engine to the wheels. Most of the competition utilise a simpler variable belt drive transmission, similar in principle to what you might see on the drum drive of a combine. Many would feel (rightly or wrongly) that for agricultural purposes the hydrostatic unit is the better option.
Kubota match the hydrostatic drive on the RTV to a three-range gearbox -- low, medium and high -- to provide variable speeds and capacities for all envisaged tasks. The range selections, and reverse, are selected with a gearstick mounted on the centre of the dash.
On our test machine it was tricky enough to get gears and had a tendency to creep when in gear at idle. Most of the linkages from the vehicle controls are by cable back to the transmission and engine, so there was probably some adjustment required to neutralise the hydrostatic drive at engine idle.
That said, you really do need to select the appropriate gear range for the load or terrain as the little three-pot Kubota engine will try its damnedest to keep the show on the road, but it will stall if the load is too great or the hill too steep. The Kubota unit develops just 21hp (16kw) and it is not enough for this machine -- there are lawn mowers out there with more power. The RTV weighs about one tonne before you put a load on, or driver into it.
It drives like most hydrostatically driven machines do, all on the accelerator pedal. Again, outdoing most of the competition, the RTV 900 is equipped with wet brakes on all four corners. With the hydrostatic drive though, I found you rarely, if ever, use them, as lifting your foot all the way off the accelerator pedal will bring the vehicle to a stop. On a dry surface, with plenty of grip, lift your foot too quickly off the accelerator pedal and you will find yourself inspecting the windscreen from very close quarters -- this observation is based on personal experience.
As mentioned earlier, this is a left-hand drive machine and rarely presented any problems from its orientation. When it did, a bench seat and clear floor enable rapid re-orientation to the side with the wheel on, without having to expose yourself to external embarrassment. Equipped with the optional cab, the test RTV facilitated this even further.
The first day we used the RTV the sun shone as hard as it was able for this time of year and I considered removing the doors as they almost felt like a hindrance on this little machine. The next day it rained as hard as it could (for any time of the year) so, respect for the doors. In fact, buying a machine like this, regardless of the make, without a cab structure to keep you dry is a bit like wearing socks with sandals ... pointless.
So to sum up, the Kubota RTV 900 is perhaps the highest-spec vehicle in its class. It has hydrostatic drive, wet brakes all round, power steering, external hydraulic service and much more besides.
On the negative side, I feel it could do with another barn of horses under the bonnet, coupled with a bigger body to extend its appeal.
I'm not quite sure where it would actually fit into on the farming front. It would be a useful tool for grounds keeping, golf-course maintenance or maybe even the horse industry. A smaller ATV/quad would certainly have the edge for speed, power and agility (not to mention price) around the farm.
Kubota's RTV and similar machines from other manufacturers perhaps would have a certain appeal, especially to those who favour accessibility, comfort and safety over speed.
A lot of engineering has gone into this Kubota machine and if you were considering buying one second-hand, be sure to get it checked over properly as they are not cheap.
A new, entry level RTV 900 would set you back about €13,000 + VAT, that's way before you even talk about a cab. The second-hand machine we had a loan of for this report has an asking price of €9,000 including VAT.