Kubota RTV 500/610 mule Opinions

JBN · Oct 20, 2009

If you want the 500 RTV to go faster, screw the bolt in on the bottom of the accelerator pedal in farther. I did and saw a big difference.

Stonehaller · Oct 20, 2009

JBN said:
If you want the 500 RTV to go faster, screw the bolt in on the bottom of the accelerator pedal in farther. I did and saw a big difference.

Be careful that you are not over stressing the throttle cable. I had a post with some pictures about that adjustment here:

http://www.tractorbynet.com/forums/atvs-utility-vehicles/143009-rtv-500-top-speed-enhancement-2.html

timswi · Oct 20, 2009

Stonehaller said:
Be careful that you are not over stressing the throttle cable. I had a post with some pictures about that adjustment here:

http://www.tractorbynet.com/forums/atvs-utility-vehicles/143009-rtv-500-top-speed-enhancement-2.html

Stonehaller, I have about 1/4 of gas pedal before the linkage moves at the servo, is that the same as yours?

Stonehaller · Oct 21, 2009

Timswi, I will have to check this weekend and let you know. My initial thought is that there should be a little free play to insure that the valve gets to the neutral position when you take you foot off the peddle.

Stonehaller · Oct 24, 2009

timswi said:
Stonehaller, I have about 1/4 of gas pedal before the linkage moves at the servo, is that the same as yours?

Timswi,

There is no free play between the peddle and the trans. servo on my RTV500. The bell crank and linkage to the servo move immediately when I touch the peddle. There is free play in the throttle cable that goes from the bell crank to the engine.

The free play on yours may not be an issue as long as there is enough travel to full actuate the transmission servo. Have someone hold the peddle to the floor and then see if you can move the bell crank any further by hand. You may have to disconnect the throttle cable from the bell crank when you check this to make sure that that is not limiting the travel. If you can push it further by hand, then you should adjust the cable from the peddle to reduce the free play or adjust the stop on the peddle to give you a little more travel. Leave a little bit of travel to go in the servo valve so that the bolt under the peddle is the stop in the system, not the servo valve.

After adjusting the peddle cable and servo valve travel, you will probably have to adjust your throttle cable so that it hits the stop when the peddle is fully depressed. I see that there is also an adjustment on the governor linkage for maximum travel of the throttle cable. This adjust may be part of your problem with low power. There is an idle speed adjustment screw and a maximum engine speed adjustment screw buried under the throttle body. I labeled the maximum speed adjustment Throttle Stop in the attached picture. You could back out this screw a little before you adjust your throttle cable. This will raise the max speed that the governor regulates and potentially give you more power.

Remember the balancing act. When the peddle hits the stop, the servo valve should be at full travel, and the throttle should be at full travel.

We should probably start a new thread in the ATV discussion for this.

Stonehaller · Oct 25, 2009

I posted a revised cable adjustment procedure in the ATV discussion here:
RTV500 Throttle Adjustments - TractorByNet.com

timswi · Oct 25, 2009

Thanks Stonehaller...That was a very detailed explaination, and I will definitley look at all of your suggestions.

I did take a little of the slack out of the throttle cable so that there is about 1" of pedal travel before it engages. Before, the trottle cable didn't engage until 1/4 thottle was pressed. This really didn't do anything in terms of power. Might have a slightly higher to speed. Not noticable really.

I'll let you know what I find...Thanks again!!!

scoutcub · Oct 25, 2009

CosmoAU said:
Great info. The only experience I've had is with a RTV900. A company doing some work on the golf course I work at had one and it is definitely a tank. I don't want to hi-jak the OP thread, but does anyone have any experience with the Cub UTV? I have a Cub dealer less than a mile from my place and he has offered me what seems like a deal on a leftover UTV. It is the kohler fuel injected version, green, hurst shifter, and aftermarket rims for a tad over $8K. I just don't know anyone that has one.

I have the older version Cub with the 20 HP Kohler command, non-FI. I've never tried the others and wasn't really looking for one but a buddy (AKA Cub dealer) gave me a deal I couldn't refuse. It's got over 200 hours and has been flawless thus far. I've towed some tractors and logs around that I didn't think it would do, but did it with ease. The 4wd, diff lock and LO gear really make a difference, and I've got some steeep hills to climb. It's no speed demon, (30mph) but it'll be fine for moving wood, chainsaws, running kids around the property, etc. I also just bought a soft cab for it for ~350 on Ebay, haven't put it on yet but thought it might come in handy for rain and winter. Also has the electric dump bed which is very handy. Good luck!

timswi · Oct 25, 2009

Stonehaller,

Don't laugh too hard, but how does the throttle ends come off?...They don't seem to want to pop off as others I have worked on. The nut below the connector(bracket) is all but impossible to turn.

Stonehaller · Oct 25, 2009

Timswi,

You do not actually have to disconnect the throttle cable. There are two nuts on either side of the bracket. Just loosen those so the cable housing can slide back and forth enough to ensure that it is not restricting the bell crank when you push it by hand to find the full travel stop of the servo valve.