Fuel screw adjustment - Kubota d series

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alexanderfoti
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Fuel screw adjustment - Kubota d series

Post by alexanderfoti »

Hi all

Firstly, yes I purchased the nearly finished Kubota D850 superdream from Tim.

Now onto the question.

When I got the bike, I Wasnt happy with how much turn of the throttle you had, so set to make it less/harder.

Here is a picture of the throttle arrangement:

Image

What I did was drill the rivets on the arm, and move the adjuster further to the right. Whilst this did work, it gave me too hard of a throttle.

Whilst doing this, I Stripped the threads in the head for the bolt holding the ali plate on. These the adjuster lever plate in place. I had to remove all 4, drill out the whole and put a helicoil in.

I kept the springs connect and just moved the place out of the way, I didn't stretch them or put lots of force onto them. I was careful with this.

After realising that It was too hard, I put it back to how you see it above, but rather oddly, the lever action has moved towards to the bottom of the image. I have had to screw in the idle adjuster screw 5/6 turns, and also had to screw OUT the fuel adjustment screw 2-3 turns(!) to get it back to the same power output as before.

Not quite sure whats happened there.

Anyway, now its running as it was before, I would like to know how to tune the fuel screw. At the moment I have it set to that if i'm going 15mph, and twist the throttle to full, I get a small puff of smoke, then the CVT shifts up, then the smoke seems to dissapear.

Any assistance?
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Diesel Dave
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Re: Fuel screw adjustment - Kubota d series

Post by Diesel Dave »

Sounds like you have it set about right.

The easiest way I have found is to get someone to ride your bike along a big road with a slight hill at full throttle - ride behind it looking at your exhaust and it should give just a smidgin of black smoke.
alexanderfoti
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Posts: 1290
Joined: Fri Jul 15, 2011 4:22 pm
Location: London

Re: Fuel screw adjustment - Kubota d series

Post by alexanderfoti »

Excellent. Good to know I have it on the right track! Thanks. I'll try that.
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