Gas quality and undesirable effects of ethanol fuel blends on a 1st gen VMAX

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91 around here has no ethanol. I use that whenever the bike is going to be sitting for a bit especially over winter. Has always worked for me.
 
Hi guys, I have a 1992 1st gen Europen spec bike, that at least when it was made was designed to run on regular grade gasoline.

The problem here in spain (and all over Europe) is the increased amount of ethanol that is mandated to be added to the gas.

Regular grade gas here is 95 but this is about the same as USA 91, this in itself is not an issue, but what is, is that 10% ethanol is mandated to be in regular gasoline (now called E10).

It is the ethanol that is the potential problem, for damaging fuel lines and gumming up the carb internals and having a lower energy content in the fuel, due to the percentage of ethanol in the mix, as well as not staying mixed very well for any appreciable period of non use/storage etc etc.

Due to this I have been using 98 octane Shell v power or BP ultimate (equivalent to US 93/94), this didn't used to contain any ethanol, but now even the premium gas has to have 5% ethanol. I noticed this a few weeks back at the Shell gas station use.

It looks like I will have to change all of the fuel lines for ones that are better resistant to the ethanol content, which does cause damage to fuel lines not designed for it.

Ethanol is a bummer for older bikes (or cars etc), especially when there is no way of avoiding gas that contains it (at least here in spain anyway).
gas here has been an exact 7% ethanol solution for 30? years. I've never seen or heard of a ruined fuel line. 3 more % eats thru rubber?
Is that what happens?
 
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gas here has been an exact 7% ethanol solution for 30? years. I've never seen or heard of a ruined fuel line. 3 more % eats thru rubber?
Is that what happens?

[/QUOTE]
Hi guys, I have a 1992 1st gen Europen spec bike, that at least when it was made was designed to run on regular grade gasoline.

The problem here in spain (and all over Europe) is the increased amount of ethanol that is mandated to be added to the gas.

Regular grade gas here is 95 but this is about the same as USA 91, this in itself is not an issue, but what is, is that 10% ethanol is mandated to be in regular gasoline (now called E10).

It is the ethanol that is the potential problem, for damaging fuel lines and gumming up the carb internals and having a lower energy content in the fuel, due to the percentage of ethanol in the mix, as well as not staying mixed very well for any appreciable period of non use/storage etc etc.

Due to this I have been using 98 octane Shell v power or BP ultimate (equivalent to US 93/94), this didn't used to contain any ethanol, but now even the premium gas has to have 5% ethanol. I noticed this a few weeks back at the Shell gas station use.

It looks like I will have to change all of the fuel lines for ones that are better resistant to the ethanol content, which does cause damage to fuel lines not designed for it.

Ethanol is a bummer for older bikes (or cars etc), especially when there is no way of avoiding gas that contains it (at least here in spain anyway).
US gas pumps push exactly 7%ethanol since the begining of ethanol nobody ever had to replace fuel lines behind this, "NEVER HEArD OF IT". 🐹😍
 

US gas pumps push exactly 7%ethanol since the begining of ethanol nobody ever had to replace fuel lines behind this, "NEVER HEArD OF IT". 🐹😍
[/QUOTE]
Hi, the gas here in spain is either E5 98octane(US 93/94 equivalent) or E10 95octane(US 91 equivalent). It isn't just the ethanol that is the problem though, the other additives added to stop the ethanol dropping out of the mix can bring their own problems.

My friend who works at BP fuel development dept told me a few years back (when ethanol was first put into regular european gas) that there were many issues with fuel line and carb problems caused by these extra additives added to prevent drop out of the ethanol, as well as issues with the ethanol itself. Also as ethanol has a lower energy potential when compared to straight gas, the percentage of ethanol added to the gas actually reduced the power development potential of an engine running on it when compared to straight regular gas.

Many years ago I raced a grass track bike that ran on Methanol (wood alcohol), the increases needed to the carb jets and needles/slides etc etc were huge, around 90% when compared to straight gasoline. However although the bike used a hell of a lot more fuel with Methanol when compared to straight gas, the main advantage (for racing anyway), was that much higher compression ratios could be used. Eg gas 9-1 or even 10-1 compression ratio, where Methanol could go up to 13-1, or as high as it was possible without valve to piston contact using special pistons etc etc.

What this means is that ethanol will raise the octane rating when mixed with gasoline, but does in fact give lower gas mileage almost as a direct result of the percentage of added alcohol to the fuel. This is when the engine has not been modified to take advantage of the higher octane number of a mixed ethanol/gasoline fuel.

However with regular gas containing ethanol, the ethanol is used to raise the octane level without using many other additives that also raise octane levels.

So the bottom line is that with a fixed octane fuel, whether using an ethanol mix or straight gas, a reduction of efficiency (total power output) will result with the ethanol gas mix, when compared to straight gas.

I appreciate that V-MAX's are designed to run on regular grade gas, but the situation now, where some of us feel forced to use higher octane gas (Euro 98) that contains less ethanol (5%) when compared to regular gas (EU95) with 10% ethanol, engine mods might be viable to claw back some of the potential power losses.

EG higher compression pistons and or increased ignition advance to maximise the higher octane in the euro 98 (5% ethanol) gas.
Clearly a shift in ignition timing (as V-Max's already have a 10.5 - 1 compression ratio) might be viable, to take advantage of the higher octane fuel.

Whether this can be done on a V-MAX in a straight forward way is as yet unclear, however in my long years of experience working with experimental engines and race engines, an ignition advance of 1 or 2 degress might be a viable starting point.

I must point out though that this is just food for thought at the moment.
 
US gas pumps push exactly 7%ethanol since the begining of ethanol nobody ever had to replace fuel lines behind this, "NEVER HEArD OF IT". 🐹😍
Hi, the gas here in spain is either E5 98octane(US 93/94 equivalent) or E10 95octane(US 91 equivalent). It isn't just the ethanol that is the problem though, the other additives added to stop the ethanol dropping out of the mix can bring their own problems.

My friend who works at BP fuel development dept told me a few years back (when ethanol was first put into regular european gas) that there were many issues with fuel line and carb problems caused by these extra additives added to prevent drop out of the ethanol, as well as issues with the ethanol itself. Also as ethanol has a lower energy potential when compared to straight gas, the percentage of ethanol added to the gas actually reduced the power development potential of an engine running on it when compared to straight regular gas.

Many years ago I raced a grass track bike that ran on Methanol (wood alcohol), the increases needed to the carb jets and needles/slides etc etc were huge, around 90% when compared to straight gasoline. However although the bike used a hell of a lot more fuel with Methanol when compared to straight gas, the main advantage (for racing anyway), was that much higher compression ratios could be used. Eg gas 9-1 or even 10-1 compression ratio, where Methanol could go up to 13-1, or as high as it was possible without valve to piston contact using special pistons etc etc.

What this means is that ethanol will raise the octane rating when mixed with gasoline, but does in fact give lower gas mileage almost as a direct result of the percentage of added alcohol to the fuel. This is when the engine has not been modified to take advantage of the higher octane number of a mixed ethanol/gasoline fuel.

However with regular gas containing ethanol, the ethanol is used to raise the octane level without using many other additives that also raise octane levels.

So the bottom line is that with a fixed octane fuel, whether using an ethanol mix or straight gas, a reduction of efficiency (total power output) will result with the ethanol gas mix, when compared to straight gas.

I appreciate that V-MAX's are designed to run on regular grade gas, but the situation now, where some of us feel forced to use higher octane gas (Euro 98) that contains less ethanol (5%) when compared to regular gas (EU95) with 10% ethanol, engine mods might be viable to claw back some of the potential power losses.

EG higher compression pistons and or increased ignition advance to maximise the higher octane in the euro 98 (5% ethanol) gas.
Clearly a shift in ignition timing (as V-Max's already have a 10.5 - 1 compression ratio) might be viable, to take advantage of the higher octane fuel.

Whether this can be done on a V-MAX in a straight forward way is as yet unclear, however in my long years of experience working with experimental engines and race engines, an ignition advance of 1 or 2 degress might be a viable starting point.

I must point out though that this is just food for thought at the moment.
[/QUOTE]
Dynamax3000! Oh boy eBay hear I come. Gimmie, gimme, gimme, that thing.
 
I imported my 1997 from Europe half a year ago. I haven't seen much difference in gasolines at all. I used Shell products in Europe and I use them here in Texas. I ride my bike often and if the weather doesn't permit that, I run the engine in my garage once a week. I didn't need to change anything nor have I seen anything being different.
 
The problem I have had with ethanol fuel is it attracts water and allows it to be in solution with the gasoline. Nothing corrodes an aluminum carburetor faster than water in your fuel. Particularly hard on pilot systems. Yes, I speak from personal experience.
 
I've tried really hard to get those stupid carburetors out of my life but it just can't be done. (YET)

Weed whips, leaf blowers, lawn mowers, snoblowers, snomobiles, old dirt bikes, old road bikes, and of course Gen 1 Maxes. (The Max is just about the ONLY thing listed worth putting up with the nuisance factor. They're a marvel of engineering, it's the ethanol that's stupid.
 
Hi, the gas here in spain is either E5 98octane(US 93/94 equivalent) or E10 95octane(US 91 equivalent). It isn't just the ethanol that is the problem though, the other additives added to stop the ethanol dropping out of the mix can bring their own problems.

My friend who works at BP fuel development dept told me a few years back (when ethanol was first put into regular european gas) that there were many issues with fuel line and carb problems caused by these extra additives added to prevent drop out of the ethanol, as well as issues with the ethanol itself. Also as ethanol has a lower energy potential when compared to straight gas, the percentage of ethanol added to the gas actually reduced the power development potential of an engine running on it when compared to straight regular gas.
Dynamax3000! Oh boy eBay hear I come. Gimmie, gimme, gimme, that thing.
[/QUOTE]


A great unexpected song from 1970!

I have no problems using the 10% ethanol gas we have today. If I'm not going to be using something for awhile, I just run the carb(s) dry.

Yesterday I used my 4K psi pressure washer and my 'flying saucer' rotating wand disc cleaner to get mildew off the sidewalk and driveway. The Honda single cylinder engine is sitting run dry, and because I may not use it for extended times I also empty it. When I turned it over a couple of times with the ignition off, and then switched on, it started immediately. I ran it for about 1.5 hours and ran it dry, and then drained the tank. Until next time, my pressure washer. I use 10% ethanol gasoline 87 octane & have no issues.
 
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My contribution to this. I got my 2007 in 2016 - that's 7.5 years ago. Here in Canada, I have always been running 87 Octane with what is written 'up to 10% Ethanol' in it. The carbs bogged up after a while - I wasn't surprised as I had no idea how they were maintained before. I learnt about Seafoam and started adding it. Eventually the bike couldn't run properly. I filled up the carbs with Seafoam into the disconnected hose while running until it choked. Left it overnight, drained bowls, connected fuel, started up, filled up with Seafoam until choked and left again. Drain next day and reconnect back to normal. Bike ran like new!

I started adding Seafoam randomly without any schedule set. After a couple years did the full Seafoam treatment again. Last year I removed the airbox and covers and squirted Seafoam in every hole, like the shotgun procedure suggests and more.

The one constant has been adding Seafoam once in a while, and Marvel Mystery Oil as well, but not as often.

The past few months the bike has been idling kind of like a Harley on cold start, and it's been taking much longer to stabilize when warm. Overall I'd say kind of flaky and underperforming. I thought finally the carbs need to come off. But I also thought about the Voltage I was getting, and I thought definitely too low. So I installed aftermarket Shindengen series regulator SH847 (RM Stator) - the 50 Watts biggest and baddest upgrade available from what I hear. Wow!! Vmax is like new.

I threw in the last paragraph, straying kind of from the fuel topic, to show that using E10 87 gasoline I didn't need to remove the carbs even once and the bike runs great like that with original fuel lines, and the tank is spotless inside. I never park the bike without use longer than 2-3 weeks, and I fill up with Ethanol free at those times.

And about the Voltage - after doing the regulator upgrade, I highly recommend everyone doing it. I have no doubt that with age the old electronics deteriorate, and replacing them with new technology makes the bike run better.
 

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