I am having problems with E10 fuel causing a dropped cylinder and wondering how common this is and looking for any remedies. Same with E5. I get this problem if the bike has not been run in a few weeks. Just put another set of carbs on and it's running fine again with the same fuel. Seems to be a blocked pilot jet or something in the pilot circuit as it will start using Easystart or whatever it runs fine other than at low revs ie it won't idle and drops a cylinder at low rpms but revs fine and runs on both cylinders with a bit of throttle. I know there's an issue with E10 and the ethanol seperating/causing water. Anyone aware if this blocks something and any solutions? I have bought some Sta-Bil and hoping it will solve the problem. Not sure if fuel has got worse in the last couple of years as this only started happening in the last year or so.

PS Model is a EX(1999). I am in the UK and E10 and E5 fuel are my only options.


Thanks in advance. 

Should not be a problem,

Is your tank clean, particles in there can block jets, rubber hosing also deteriorates and with effanol can break off and block jets.

Effanol attracts water which goes to the bottom of the tank. This can get into the carb float bowl and cause problems also.

Id take off the float bowl and have a good look.

As a tip, you can get ethanol free gas at any boat dock/harbour. Boat petrol is not allowed to have any "additives". It's more expensive but maybe give it a try and see if the problem remains.

good luck.

If it only happens with E10 and not E5, it's possible that the E10 is just making the bike run too lean for your fuel-mixture screw setting.

Thanks. Will check out the float bowls. Pretty sure the tank is fine. There's a filter in the tank that should ensure the fuel is clean, so don't think this is the problem. I have the same issue with E5 unfortunately, so am hoping that using Sta-Bil will solve the problem. Thanks again.

Stabilizer only makes it "winterizable"  . It usually doesnt fix the gas

Sorry, I don't understand. What does "winterizable" mean?
I thought that it prevents the ethanol seperating and creating water. So therefore it does "fix" the fuel.

Stabil prevents fuel from degrading due to oxidation; good for when you are storing the bike.

I don't think the ethanol is separating into water. In Canada, we have had 10% ethanol in regular gas for decades. The only complaints I've ever heard are that it dries out the rubber parts of carbs; and that it "thins" out the fuel, because it is less combustible (a little less power).

If you have water, it is probably just condensation in the tank.

Your issue sounds more like a partially blocked pilot jet.

The ethanol does not separate, it is hydrophilic, so it attracts water, that then separates.

Yeah, I remember when leaving canada in 2017 that finding non ethanol fuel was getting harder and harder.
Here in Switzerland we have no homegrown corn industry to subsidise, so fuel is pure.

However when riding in France and having to fill up I always try to run my tank dry before filling with pure gas again.

Anyone know if this seperation of water due to the ethanol being hydrophobic could lead to a blockage in the pilot circuit as this appears to be what's happening? Thanks again. 👍🏼

If E5 is all you can get you need to run the bike frequently. Like put a tank of gas through at least every 3 months. If E5 or E10 gas gets old it will cause problems.