Sold Honda Kubota

[Tim]

T

Diesel

Diesel Honda Superdream 500cc 1979

Now sold, thanks for looking.

500cc turbocharged and inter-cooled Kubota twin cylinder diesel fitted in a Superdream frame.
Transmission via CVT ( from Axiam car ) and rear drive via 30mm wide toothed belt .
MOTed till April 2016 , good tyres , the tank and panels have been repainted and reasonably presentable for its age but not perfect check out the photos
It has done approx 2000 miles since the conversion and ironed out any teething problems and now runs as it should

It has proved to be very reliability and with outstanding fuel consumption , if you drive it like a granny I have exceeded 130 mpg.

The turbo boost pressure is set for economy but it can be set for increase performance .

Brilliant fun to ride, not too noisy , good in towns or the open road .

Recent service and new final drive belt fitted. New brake pads , fork seals , seat recently recovered , new battery last year.

Comes with spare rear and alternator belt + specification sheet of the major parts and where to source them

Includes additional Z400 engine . I purchased It for the ancillaries and can't vouch for its condition but knowing kubota quality possibly in ok condition .

The v5 is currently with DVLA for registering changes in colour and fuel type but I have kept a photocopy

There is a short you tube clip extolling its virtues ! http://youtu.be/_K0-FlgHcA0 or search youtube for "Diesel Kubota Superdream "


£2000 or nearest offer
Somerset
Tel 01963 350668

[BertTrack]

I can't stop thinking about this one.

[UAofE]

Very good build especially at that low asking price. Changes would have to be done to the intercooler though, its not doing anything where its placed.

[BertTrack]

Very good build especially at that low asking price. Changes would have to be done to the intercooler though, its not doing anything where its placed.

It's doing something. And i don't think it needs a big inter cooler to begin with. Even the Track does not have an inter cooler. And so far the only time it has had trouble with high inlet temperatures was when the turbo pressure was set too high (not by me).

So placement isn't a big deal. Especially if it's not running more than 0.5 bar over pressure. (I don't know what this one runs at)

[UAofE]

Where its placed, the only real benefit is adding plenum surge volume. A pick up hood or even an angled scoop lip on the back edge would make a big difference.

[Tim]

Hi
Your both right !
I was concerned with possible issues of pulsing using small engines with turbos . So you quite right about using the intercooler to increase the plenum chamber volume between the turbo and the inlet valves. In deed still at lower rpm the gauge needle tends to fluctuate wildly .

No calculations withe the intercooler just what I could get my hands on. In fact is a car one cut down but it's a pain because if you corner the bike it hard it's the first this to rub the road.
I haven't measured for temperature differences but think as you pointed out its only really going to be an issue with the high pressure boosting and compressing of the air .

I have increased the maximum fuel by 0.25mm on the rack and it max boost at the moment is around 4 psi . Set at this it's power output is similar to 800cc diesel triple . On the the ride back from the big knock I couldn't gain a lead over the turbo z 482 bike


On the latest bike a manual version using the same engine I have increased the max fuel by 1/4 of a turn approx 0 .25mm of the rack and the boost now runs closer to 7 psi .with much enhanced performance . This is using with new £170 clone turbo of the rhb31 turbo.

One full turn or 1mm increase of the rack sends the boost to 14 psi and above but slightly concerned for the engines life expectancy with marked surge in performance . I think for this kind of boost pressure reduced compression ratio and advanced timing is recommended but it all gets a bit silly as the fuel consumption drops hugely
It's does allow you to push along at speeds not normally associated with diesel bikes!
( it is lovely fun to ride and sound really great + covers every one in black smoke until the boost pressure rises !)
In addition I have removed the max speed stop and it now limits at 4200 rpm . Is seem happy by I guess time will tell if this is wise! If your going the this year big knock it would be good to meet up.

Kind Regards
Tim

[UAofE]

So you're using the clone turbo with a wired closed wastegate? I have one as well but I might consider getting a Garrett GT06 later on as it has a better flow low range.