Carbs and ethanol..

Went for a run on the Convert today after an enforced lay off due to a shoulder op. It’s been sat in my garage on an Optimate for three months. About a mile from home it started to run like a pig, and refused to run at more than a few thousands revs. I limped home and whipped out the plugs, all seemed good. Then I drained the carbs…, great globs of water came out with the fuel. Bloody water absorbing fuel again! I’d had just the same problem with my carb fitted scooter last winter…
I never have a problem with either of my petrol injected bikes.
I’m so fed up with this, and it’s only going to get worse for carb fitted bikes as ethanol content is increased, that I’m seriously thinking of selling my Convert and Honda scoot…

tis easy enuff to drain the float bowls prior Al…I always do it with my duke if hes laid up for a bit…mindyou we tend to use premium fuels in ours so you dont get the problem really…
Am tempted to say just put the good stuff in…but then I know you are of farming stock ! :laughing:

plus 1 for that Kate, I never use standard 95 without additive and otherwise a big fan of Tesco’s 99 (but not of anything else from them!). Never had an issue with water, even when stored over winter.

With your Convert it will definitely run better with the good stuff.
Paul Harris switches off his fuel half a mile from home to drain his carbs, and that was 15 years ago.
However if you genuinely want to sell I know a good looking ginger haired ex hero veteran who would be interested depending on price.

Never have a problem with Co op 99 as long as the water is hot enough :smiley:

Yip, +1 for the expensive stuff…my Triumph likes it, seems to run better. Don’t notice a difference in the Guzzi but use it anyway in an attempt to delay the expanding plastic fuel tank trick!

I may have a few years on other posters on here and I can see the sun setting on my riding days, especially after two shoulder ops over the last few years. I can’t really be a*sed anymore messing about with fuel etc, and yes, I refuse to pay for so called premium fuel or ‘fools and their money soon parted’ additives. I expect to get on a bike and ride, even if it’s been stood for a few months, is that too much to ask?..

Well, we only ever used a proper additive for a very high compression race engine, apart from that we dont really have to ‘mess’…the geography of a duke engine is a tad different, it obviously has one carb pointing skywards.

I guess you “pays your money and takes your choice” but I generally use premium fuel in my old Guzzis - Shell V-Power by choice but only because there’s 2 or 3 Shell garages nearby and it seems to work well. For the amount of mileage I do, I don’t mind the extra cost. Might try the Tesco version based on Robin’s recommendation.
If I’m not using them for a while I try to run them with the taps shut to empty the carbs, but the other thing I’ve read is to keep the tank full to reduce the amount of condensation that can form on the tank walls.

This is the thing - nobody is making petrol for carburettors anymore.

I have used Frost’s Ethomix, it’s a stabiliser, and supposed to prevent or reduce water absorption, seems quite good.

But agree if a carb’d bike is left standing MUST leave the carbs bone dry. Apart from any presence of water or not, when it evaporates the modern fuel leaves hard brown and green crap behind that, over time, clogs up everything.

Re using the expensive stuff.
I started doing this 6 months ago as my mpg had dropped to 25 mpg on my Lil’Breva.
Put Super in and back up 50 mpg. That alone is a saving.

Hi, I always use 95 octane whatever the bike I am riding, BP claims to have no ethanol in the fuel, hopefully they are speaking the truth.
My old XT yam from 1980 had no end of problems until I was told that ethanol fuel weighs differently to non ethanol fuel, readjusting the float height solved the rough running problem.
My injected Cali 1100i hates the 10% stuff, it burnt out a set of plugs in France when I miss filled with 10%, filled with 95 and all was well.
Why do we use E 10 when you get poor performance and poor fuel consumption.

A few years back in winter, my Yamaha Divvy 900 used to suffer from carb icing. The market leader in stopping this (Wynns dry fuel) was expensive, main ingredient is Isopropanol. So I bought neat IsopropanoI & I used to put this in the tank, it stopped the problem, my understanding is that it mixes with water and it disperses into the petrol, and the water is then in minute quantity and gets burnt off. This carb icing only happened in winter, in the morning on the M27 when in the dip by the water at Swanwick.
I still occasionally put a little in my bikes once in a while in the hope that any water lurking in the bottom of the tank gets dissolved.

My experience of carburettor icing on a vintage car is that it is due to the latent heat of evaporation that occurs at the carburettor venturi. In Winter, with moist air, the inlet tract is sufficiently cold for the moisture in the air to freeze not any moisture in the fuel. This is why many cars had a hot spot between the inlet and exhaust manifolds.