Hello to all from Old Clunker.

[old clunker]

At last have a diesel motorbike, after visiting this site for about three years now on the sidelines, and have got lots of useful information from the numerous posts, looking at various possibilities.
Having great difficulty in sourcing a reasonably priced classic donor bike frame, and seeing that it would cost more in new tools and welding gear etc., and only having limited workshop facilities - I visited Henry Price last year, and was quite impressed with the conversion work, and after a test ride at his place in Gloucestershire, I asked Henry to build a pre-1972 Royal Enfield conversion to my requirements, when an ex. Indian frame became available. It also has electric start, and a sidestand which is useful. So after a few months waiting, now I have a 1971 classic motorbike, with cheap classic insurance and no road tax to pay.
I've just run the 406cc Suntom engine in after several hundred miles, and had only a few very minor faults with the motorbike overall. I've also done some mods as well, and after the first engine oil change, I'm experimenting with biofuel vegetable oil mixes, and I have currently run the engine for about an hour at various different throttle settings with my current veggie oil blend, with no running problems so far.
I'll keep you posted with my progress and experiences with running the motorbike. So far, the vegetable oil blend costs about £1.17 / litre which is considerably less than the price of diesel! and the exhaust smell is a bit like a barbecue smell with the hint of diesel still in the fuel tank! I hope to get the vegefuel cost down a bit more, with my latest blends of 'fuel'. Fuel consumption so far in the running in stage is about 140mpg, which is good already!

Performance so far, is a max 52 mph indicated and confirmed on my additional digital speed counter! with some throttle left, whilst running in the motorbike on diesel. Unfortunately I couldn't take it any faster, as I live in London, and was speeding just a little bit in a quiet lane on a Sunday morning!
It's similar to a 125cc bike performance wise, except with a lot more weight, much more low down revs engine torque, and much better road handling. My previous bike was a Jap grey import 1970's styling Honda CG125 for commuting, and the Royal Enfield diesel performance is quite similar.

Anyway, all of you keep up the good work with diesel motorbikes, and interesting posts.

[Dougy]

Nice one clunker it looks good that I'm a bit envious of your free tax though lol, I used to have a tax exempt Landy and it used to tickle me when they asked do you want 6 or 12 months tax.....erm 12 I think my good man

[old clunker]

Thanks for that Dougy, good luck with your projects.

[Stuart]

Nice one there old Clunker There will be a few people interested to see you you get on running it on vegetable oil. If you ever feel like sharing you blends then please do - especially if your using used oil

[old clunker]

Thanks for your comments Stuart. When I've proven the reliability of the vegetable oil mixes, including in cold weather, I'll share the info about what I've found, and what works. I'm using new vegetable oil, 15 litres of Asda's cheapest and finest genetically modified oil! Discounted during Ramadan this month as well!! Also managed to stock up with Tesco's 10 litre discounted sunflower oil at the moment.
So far I've done 26 miles on the veggie oil mix, and the engine runs much smoother, smoother power delivery and with no diesel knock so far. It looks like the engine likes the first blend and seems to suit it. The other blend I've made is cheaper to produce, and it will be interesting to compare it's performance as well, eventually.

[Stuart]

Very well done Best place for genetically modified oil eh?

[coachgeo]

Some vegie oil blend hints learned thru reading not real world use of my own.

1. If engine gets more quiet... as most say happens then..... you may no longer be at best efficiency. If it knocks it is happy. You may need to retune the engine so it knocks again is basic principle. The timing of burn of the blend is different. It combust at a different time than straight dino-diesel thus the need for change. Unfortunately there is no easy/cheap way to measure how complete combustion has occured. Some have used a simple one mile (or known distance) route with a slight upgrade so the engine works. Then measure speed and or time it takes to drive it; extrapolating out that more speed/less time means the engine is working more effciently.

2. Heat and blend, esp. in the winter is your best bet. Consider figuring out a way to heat your fuel blend some to thin it even more.

3. start up is the most critical; esp. when using a blend. Consider some way to bring engine up to normal operating temps PRIOR to starting the engine. The cool cylinder walls at startup/warmup and a fuel that is not burning as optimally as possible is what cokes the engine is what I've read. A poorly tuned diesel will coke too when the engine is cool. So for longevity of the engine this is most critical area. Im considering using an Propane camp bottle and a home made coolant heater before startup, but I do plan on using a liquid cooled engine. Another potential benny from this, because you have it on board anyway... propane injection. Say for a passing gear... you shoot a little propane into the intake. Propane injection gives you a booste similar to Nitrous injection does a petrol engine. This also helps clean the engine of depsits so I've read. A shore powered electric coolant heater being built in too is in the long term plans. My home does not have shore power where my office will. Opposit is true for most.

lot of good info here

http://www.burnveg.com/forum/forum-4.html

PS- on that site and on the net in general search for the Peter Schur blend. very detailed and studied blend. Not sure I spelled it right.

[old clunker]

Thanks for the extra info coachgeo, my approach is to try to take the most 'simple' path (?) To simulate 'dino diesel' as you put it!
So I get the viscocity and cetane value of the vegetable oil as similar to diesel, to give the fuel pump and fuel injector an easy time.
I started with a 100ml measure of vegetable oil, and gradually added small (ml) measured amounts of flammable solvents to get the viscocity the same as a sample of diesel that I keep as a reference in a small jar. Then when the viscocity is as close as I can get it, I scale up the proportion measurements to get either litres or gallons of veggie mix. In the end I add a very small measured amount of cetane enhancer to the gallon container.
From what I've read, mothballs which contain Naptha, or liquid Napthta if it can be obtained, can also be used to enhance the cetane value of the vegefuel.

I've been doing quite a bit of reading about running on vegetable oil, especially the pioneers of it in cars, from about 2000, when we had the great fuel shortage/strike and price hike in the U.K. From their comments, running older type diesel engines on veggie oil mixes have been very positive.
The diesel engines tend to run much cleaner on veggie oil as well. Any old crud blocking up the injector, pump, or filter is from the result of long term running on diesel, and then changing over to veggie oil, from people's experiences!

As for the diesel engine running properly on the motorbike, it revs ok, can overtake slower traffic with no problems, and only smokes lightly for a short time with pale white smoke when revved. Diesel smokes with black/dark grey smoke when revved. If the engine wasn't suited to the new fuel, it would be difficult to start, smoke a lot with unburnt fuel passing to the exhaust, and rev poorly, with slow acceleration. Have experienced all these problems in the past, with petrol engines with a 'dodgy' carburettor!

A slightly different technique is needed to start now, by turning the engine over three times with the decompressor compressed. This puts enough veggie fuel onto the piston to fire up. Then start up the engine, and most times, it starts first time. I think the fuel priming is needed, since the veggie oil burns with a bit less energy per unit of fuel.
When I pull away from cold, the exhaust smokes lightly for a bit with white smoke, similar to a 2 stroke, and then clears up. With the engine warm, the fuel pipes are routed around the engine, so they get quite warm also, and the fuel feed pipe to the injector is also nice and warm, so the oil should be at a reasonable viscocity, similar to diesel.
The engine has a softer diesel knock now, not the harsh metallic almost slapping knock it had before at times, when running on diesel. And has less vibration as well.

We will see what happens when I give it a longer trial, running on the vegetable oil blend. And I will let everone who is interested, know about my experiences - either good or bad!!! Another 12 miles done today, with a seemingly happy diesel engine!