Had an older guy (~75yrs) come to buy some parts, he turned up driving an S800 Honda (car) and showed me photos of his ~15 bike collection..lots of oldies, Gold Star, Triumph and the like, couple of Ducati singles, a 900 desmo race bike and his current project 996. We were talking about upkeep and leaving bikes standing for a while and then the nature of modern fuels. It turns out he puts up to 10% diesel in with his petrol and swore it was a good thing to do for lubrification etc... I can't seem to find anything that refutes or confirms his point. Can anyone shed light?
Diesel in the petrol will reduce performance, and may well damage a modern highly tuned engine. If there were a benefit, Shell & Co would be selling it to us for a higher price, premixed, as their latest great idea. I've heard that back in the day, in super cold places, people choose to put a little petrol in the diesel to reduce the gelling effect of temperature. As petrol is a solvent that may work but it also removes some of the lube for the engine... Maybe old diesels weren't so susceptible to problems afterall they weren't fitted with hi comp motors & turbos then? Personally I've no idea, and I certainly wouldn't do it unless I needed to escape certain death from a Polar bear or something!
There's nothing really magic about diesel oil - it's just a tightly-specified light oil. The above would be a lot like a 2-stroke mixture that many an old bike & car engine managed to work very well on. Compression ratio for diesel engines is way more than all petrol bike engines (even 'high-performance' engines are only ~14:1) so the diesel oil won't make the engine 'diesel'... Yes - modern electronic sensors might gum up, etc but I'd say your old bloke knows what he's doing.
Yes perhaps a big penguin could do some damage with its beak? I don't think they chase people so if you leave them alone its probably OK? Unlike the bloody Polar bear!
Do you thing burning the oil would clog up the bike though? Would you put diesel in yours if you were storing it?
Probably not with an injected bike, but maybe 10%-ish is a bit much and it'd smoke a bit. My old Seagull 4hp 2-stroke outboard was something like 16:1 mix (so about 6%) and it never fouled a plug, but it did leave an oil slick behind it Food for thought I'd say...
Great little engines those Seagulls -I had one too. Took me & the boys up and down the river Hamble endlessly.
Bears are already mean AF. I can't imagine how much worse it would be if the bear had a cactus stuffed up its ass.
Old time hack used to be to add 10% petrol into a diesel tank in winter. Can see more harm than good adding diesel to petrol. However, if it works for him then leave him to it. Personally, I would not copy. I used to run my diesel 4x4 on a 50/50 mix of veg oil/diesel. That was when you could get veg oil for 18p per litre.
old veg oil. heard and seen that, but not in a long time and deffo not on diesels with high pressure common rail's, EGR's, oxygen sensors, cats and DPF's. maybe an old carb model. maybe. i cant think of a quicker way of reducing the efficiency of a modern petrol than firing in any light oil. modern oils are not what they were back in the day. and you can ram yer generic cover all oils too. vehicle specific or it doesn't happen in my place.
I’ve heard of people doing it but I never have. I sometimes spray the inside of the tank with Gt85 if it very low on petrol just to coat the inside for storage.
Castrol R (castor oil) - just a spoonful in a tank of petrol makes the odour of the exhaust gases more pleasant.
Done it the other way round. Putting a litre of petrol in a tankful of diesel to run hotter and clean the dpf. Ran my old Grand Vitara for years like that though apparently parafin or high grade 2 stroke oil is better.
I've been told by several mechanics about the damage modern fuel can have on older bikes and they recommend that before I store my bikes (even if it's more than a couple months), I drain the fuel tank then use a 'storage fuel' like "Aspen" which doesn't contain harmful ethanol. It is expensive fuel, but you don't need much in the tank, just run the bike on the storage fuel before laying it up. I haven't had any problems yet (touch wood)... https://aspenfuel.co.uk/products/aspen-4/
You might get away with this on an older 20+ year old diesel, but UNDER NO CIRCUMSTANCES do it on a high pressure common rail engine. About 10 years ago I absent mindedly put 2 litres of petrol in my 2013 vauxhall. I thought if I filled the tank it would amount to 5% petrol in the diesel and it would be ok. It did run, but even after several refills with diesel, it ran rougher and fuel consumption was down by about 10-15%. Modern common rail diesel pumps run very fine tolerances and use the lubrication in the diesel to lubricate. 5% petrol was enough to damage this lubrication effect and wear the pump.
There is often lots of traffic on Land Rover forums about adding small amounts of 2-stroke Oil to diesel to help them burn cleaner. Lots appear to swear by it, but as has been said several times on here doing anything like that to a modern Common Rail Diesel with EGRs etc has to be a risk. As an aside, if using 2-stroke Oil in a Diesel, or even petrol, consider the difference between motorcycle and Marine(Outboard) grades. The marine grades are far more expensive, but formulated differently as they are designed to work with outboards that run cooler and spend long periods of time running at constant speeds using 1/2 to full throttle.
Yes I was warned not to add anything to common rail engines. The Suzuki wasn't commn rail (Renault Megane engine I believe). It was very prone to dpf fouling and I used it off-road which made that worse. I actually did it first time by accident. I put four litres of petrol in it before I realised. I brimmed it with diesel and hoped fror the best. It ran great. Went better and no sooty smoke which it was terrible for when run on regular supermarket fuel, especially after dirving slowly off-road. I mentioned it to a mate who was a very good mechanic. He told me about avoiding additives in common rail engines. He said petrol does help reduce fouling and dpf clogging because it makes it burn hotter and cleaner buut it time can wear the valve seats because it reduces the lubricating effect of the diesel. He recommended paraffin which is basically all the much more expensive dpf cleaning additive is. I learned online about the 2 T oil. But it had to be a specific grade, not any old cheap stuff. I used to add one single dose mini bottle of Stihl red chainsaw oil to every 50 L of fuel. That worked very well.
