Kubota Diesel Motorcycle

coachgeo · May 6, 2013

Re: Diesel Motorcycle

coachgeo said:
Anybody got idea where to locate used parts?

particularly used parts and the ability of counter person to not need a tractor model number since I got no model number

kubota alpine · May 7, 2013

Re: Diesel Motorcycle

If you have access to a lathe its easy to put a clutch on a kubota engine.
not sure how common snowmobiles are where you are but here its no sweat to get an old one for cheap or even free.

all I done was cut the taper off the crank, machine a sholder onto it, weld it into a plate then turn the plate to size and face it off so it runs true with the taper.

I used a scrap clutch i had as a mandrel to hold the taper.

coachgeo · May 8, 2013

Re: Diesel Motorcycle

kubota alpine said:
If you have access to a lathe its easy to put a clutch on a kubota engine.
not sure how common snowmobiles are where you are but here its no sweat to get an old one for cheap or even free.

all I done was cut the taper off the crank, machine a sholder onto it, weld it into a plate then turn the plate to size and face it off so it runs true with the taper.

I used a scrap clutch i had as a mandrel to hold the taper....

The build is being done in TX so not too many snowmobiles down there but I'll see what we can borrow from your idea.

Now about oil pans? I need a different one than what I got......... different intake and exhaust manifolds too so.... any help would be appreciated

coachgeo · Dec 26, 2014

Re: Diesel Motorcycle

kubota alpine said:
If you have access to a lathe its easy to put a clutch on a kubota engine.
not sure how common snowmobiles are where you are but here its no sweat to get an old one for cheap or even free.

all I done was cut the taper off the crank, machine a sholder onto it, weld it into a plate then turn the plate to size and face it off so it runs true with the taper.

I used a scrap clutch i had as a mandrel to hold the taper.

For Archive reasons can you please download these here instead of linking to them... (links died)

coachgeo · Dec 26, 2014

Re: Diesel Motorcycle

Do any of the D722 powered things you know of have a decompression lever on the engine? Wondering if such an animal from another D722 Application can be retrofitted to my D722 from a Carrier Cooler which Im pretty sure does not have one. Can't run out and check. Engine is in TX and Im in OH.

Thinking of future solution for starting engine with dead battery since bike will have a CVT thus no push start option.

coachgeo · Jul 7, 2016

Re: Diesel Motorcycle

since someone brought up a Diesel Motorcycle today.....

I desperately need a stub shaft that will bolt to a D722 flywheel. 1" shaft diameter.

Anyone got any leads for such a beast. Curtis was machining one but a storm took out the motors of his bigger shop items and his compressor. He was having hard time making the stub shaft (he's a perfectionist) and now with no Lathe.... we're stuck at getting any further.

Been working on this thing off and on for nearly a decade now...... TIME TO

GET HER DONE!!!!

Yooper · Jul 8, 2016

Re: Diesel Motorcycle

Might be able to help you. Would need drawings with specs.

skeets · Jul 8, 2016

Re: Diesel Motorcycle

Man I really hope you get it done soon I really want to see this byitch

coachgeo · Jul 8, 2016

Re: Diesel Motorcycle

Yooper said:
Might be able to help you. Would need drawings with specs.

I'll see if Curtis can draw something up.

coachgeo · Jul 9, 2016

Re: Diesel Motorcycle

flywheel stub shaft mount dimensions. So far I understand all Super Mini series kubota were same in this mounting.

My Bike and engine is 1,000 miles away so asking here. Does below sound right if you got a super mini to measure

Bolt Circle: 130 mm (5.12”)

5 bolt pattern: thread hole size M8 thread pitch 1.25

Pilot Diameter: 106 mm (4.17”)

scottl245dt · Jul 10, 2016

Re: Diesel Motorcycle

3 cylinder kubota diesel motorcycle
http://thekneeslider.com/hydrostatic-drive-diesel-motorcycle/

Corney · Jul 11, 2016

Re: Diesel Motorcycle

coachgeo said:
since someone brought up a Diesel Motorcycle today.....

I desperately need a stub shaft that will bolt to a D722 flywheel. 1" shaft diameter.

Anyone got any leads for such a beast. Curtis was machining one but a storm took out the motors of his bigger shop items and his compressor. He was having hard time making the stub shaft (he's a perfectionist) and now with no Lathe.... we're stuck at getting any further.

Been working on this thing off and on for nearly a decade now...... TIME TO

GET HER DONE!!!!

Glad I could demotivated you! Thought you might like that Kawabota, I know it's not orange but it's diesel.

kwfiggatt · Aug 10, 2016

Re: Diesel Motorcycle

I desperately need a stub shaft that will bolt to a D722 flywheel. 1" shaft diameter.

If you still haven't found a stub shaft, Hayes mfg has them for SAE flywheels, which is what the super mini kubota uses. I believe it's a SAE 6 1/2" flywheel.

Looks like they offer them in 1.5" and 1.75" dia shafts. Their website also says that they make custom pieces.

http://www.hayescouplings.com/index.php/products/sae_stub_shafts

On another note, you were asking about the intake and exhaust manifolds available. I believe that the 3 cylinder super mini engines all use the same bolt patterns and therefore can swap manifolds. You can look at the exhaust gasket part numbers for each model of engine and see if they are the same. If so, the manifolds will probably fit.

I put a D600 exhaust manifold (belongs on a g5200 mower) on a D662 without any problems. This exhaust manifold points the exhaust towards the flywheel. The previous manifold dumped straight up and would have hit my hood. I put a D662 out of a Jacobsen Greensking IV mower into a Kubota G4200 that previously had a Z430 in it. The swap was pretty painless. I think I got the new exhaust manifold through an online Kubota dealer for something like $75 - not bad in my book and I'm cheap. A Kubota G1800 / G1900 originally had the D662 in it, FYI.

Hope this helps!

Kevin

coachgeo · Aug 10, 2016

Re: Diesel Motorcycle

kwfiggatt said:
If you still haven't found a stub shaft, Hayes mfg has them.....

Looks like they offer them in 1.5" and 1.75" dia shafts. Their website also says that they make custom pieces.

http://www.hayescouplings.com/index.php/products/sae_stub_shafts

On another note, you were asking about the intake and exhaust manifolds available. I believe that the 3 cylinder super mini engines all use the same bolt patterns and therefore can swap manifolds. You can look at the exhaust gasket part numbers for each model of engine and see if they are the same. If so, the manifolds will probably fit.

I put a D600 exhaust manifold (belongs on a g5200 mower) on a D662 without any problems. This exhaust manifold points the exhaust towards the flywheel.....

Kevin

Great info on manifolds. Hayes is great but massively expensive even before custom work which would be required cause my shaft is 1"

Yooper · Nov 20, 2016

Re: Diesel Motorcycle

coachgeo put out a call for help on fitting a Kubota diesel into a motorcycle. He was stuck at the stub shaft needed to drive his clutch (torque converter). Since this is right up my alley, I volunteered to help him out. Through some back and forth, we established the parameters he and his partner, Curtis, wanted to see for the stub shaft. They wanted to have an outside bearing to absorb some of the side torque incorporating this in with the stub shaft. They sent me the flywheel and the clutch and the following is what we settled on and what I'm currently machining.

The key word on this project is concentricity. My plan starts with machining the back side of the stub shaft, where it mates up to the flywheel. From here, I will machine a replica of the crankshaft end and mount the flywheel and sub shaft to this to insure all is concentric. I'll explain the procedure with pictures as it unfolds.

skeets · Nov 20, 2016

Re: Diesel Motorcycle

Well now this should be an interesting thread !

coachgeo · Nov 20, 2016

Re: Diesel Motorcycle

Yooper said:
coachgeo put out a call for help on fitting a Kubota diesel into a motorcycle. He was stuck at the stub shaft needed to drive his clutch (torque converter). Since this is right up my alley, I volunteered to help him out. .....

I am not worthy

BadDog · Nov 20, 2016

Re: Diesel Motorcycle

Nice work, and cool project!

Gotta love having machine tools. I haven't done anything tractor wise except for a primitive 2 stage clutch alignment shaft and some spacer bushings, but I've done lots for trucks, including doing all the machine work for putting a 6BT in a 72 Suburban (and some custom ultra-low profile air locker axle fittings). It's just generally great being able to make stuff.

Yooper · Nov 24, 2016

Re: Diesel Motorcycle

Turning the front side of the stub shaft in the lathe. Basically roughing it down so I can fit it on the flywheel for final machining. The blue on the shaft is for marking the bolt head height, which has to be taken into account because the back of the clutch must not hit these. The only M8 bolts I had were these socket heads, which are taller than a cap screw would be.

I'm wondering if a tapered bolt like the one in the last picture would work? This would allow the clutch to be a bit further inward, which is what the coach would prefer. Of coarse, it would have to get coach's approval, but does anybody have any experience if this is a good way to go?

North Idaho Wolfman · Nov 24, 2016

Yes a taper head bolt would work perfect and would cut the clearance down to nothing.

I would just use loc-tite on the bolts.

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