An acetone success

Flapdoodle

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I had tried acetone on my car without any real increase in either performance or economy, but wanted to see if it would make any difference on my HT 80.

Proponents of acetone recommend 3-4 ounces per 10 gallons of gasoline. For the 1/2 gallon tank on my bike this works out to about .2 ounces.

I got the engine running on the fuel that was already in the float bowl, got it cruising about 15 MPH. It had the familiar 4 cycling sound.

When the acetone mix reached the carburetor, there was a noticeable difference in sound with it 2 cycling in spurts a few times with an accompanying feel of acceleration. Then it settled to 2 cycling at a somewhat greater speed. I took it to town and around town. It was much smoother for the entire tank of gas, with easier starts. (my engine is not great on starting). Cold starting on successive days was also encouraging.

I know from working with cars that what works on one may not work on another seemingly identical engine. Also, I am NOT recommending acetone since I do not yet know the long term affects on plastic, fuel line items, and gaskets. I have two spare carbs so I am not taking any great chances trying this. Besides, .2 ounces per tank does not seem like a great amount of dilution.

As I learn more I will update it here.

~Flap
 
B

BSA

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I would hazard a guess that the flamability of acetone reduces the octane of the fuel to a level more suitable for HT engines.

BSA
 

DIYMark

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Acetone breaks the surface tension of the petrol so that it vaporizes better. This then reduces combustion time of a cylinder of fuel/air mix. So it basically speeds up the power stroke.

This will mean that your engine should rev higher and smoother (smoother ride and better top speed) as the combustion is taking less time.

Also because of this your torque (bottom end) dies. This is because having a "longer" combustion time favours the low RPMs. So with acetone the power stroke is short and sharp which at low RPMs causes negative outcomes.

Ill gladly try acetone next time I can get some! My HT 80 (as it currently is tuned) creates monster torque. Its like a tractor, my highway speed and uphill speed is the same (needs gears) you can even do wheelies on my bike :D

So I want to double check what I said and see if in fact my torque does die at low RPM.
 

Flapdoodle

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Acetone breaks the surface tension of the petrol so that it vaporizes better. This then reduces combustion time of a cylinder of fuel/air mix. So it basically speeds up the power stroke.

You beat me to it. I was about to post almost the same thing. Theory is acetone breaks the surface tension in a manner similar to soap on an oil slick. It takes only a very small amount to accomplish this. I wonder if having all that synthetic oil mixed in my gas tends to make it harder to vaporize.

Proponents of acetone claim you must have 100% and most sources are not that pure. They say to buy from Sally's Beauty Supply common in most cities. Mine came from Ace Hardware in the paint section. If I remember it was about $7 for a pint.

The .2 ounces I mentioned is about 1 and 1/2 teaspoons per 1/2 gallon tank. I could get 80 tank fulls (or is it tanks full? :geek:) from a $7 can.

Somewhere in here I saw a recommendation that premium gas be used in these tiny engines. Sounds like overkill, but I will get a few gallons next trip into town, and will report on it here when weather permits.

So far the acetone has not changed the float into glob that looks like half chewed Halloween candy.
 
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NunyaBidness

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...
Somewhere in here I saw a recommendation that premium gas be used in these tiny engines. Sounds like overkill, but I will get a few gallons next trip into town, and will report on it here when weather permits...

I have only seen the opposite, since the HT has a very low compression it is better to use the lower octane.
 

fastboy9

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Nice! I have a bottle of it in the garage, but I use mine quite often to clean oil off of things as it breaks it down. Is that not a worry to the lubrication?
 

DIYMark

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The car Boys are adding 2T oil to their 4T cars to over come the apparent fact that "Acetone reduces lubricity".

However, I did the calculations and for 1 litre of fuel you need 2ml of 100% Acetone (I managed to find some :pinch: :) ) Thats a dilution of like 0.002% (or 500:1) and that is so small I doubt there would be any negative effects on oil or seals.

Then again some people think that if it inst enough to effect seals its probably not enough to effect the surface tension of fuel (the sole reason why acetone works).

Try this - get a bowl of water and sprinkle some ground pepper on it. Now put the tiniest drop of detergent on your finger and touch the center of the bowl.

See, it took that pathetic amount of detergent to break the surface tension - so me thinks adding acetone is fine. However, I'm not after more economy (would be nice if it in fact does) but I'm after for the extra revs and smoother engine performance.

Lastly if this tiny amount (500:1) of acetone does infact deteriorate lubricity in the engine - so what. These HT run of 20:1.

25:1 is the richest Ive ever seen until I got a HT lol. Even then 25:1 is fairly rich ratio. None the less I do run Castrol Power 1 TTS now.

Later today Ill give the Acetone a whirl at 2ml per 1L and I will use my "old" oil (I got fully synthetic today) so I can compare the bike to how it was before.

Ill report back with what happens.

PS - Acetone will also increase the octane rating by a tiny amount. Also the "racing" 2T oils also contain a shot of xylene in them so you get a tad more octane boost (probably explains why the oil I got today claims better acceleration times)!
 
S

SirJakesus

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PS - Acetone will also increase the octane rating by a tiny amount. Also the "racing" 2T oils also contain a shot of xylene in them so you get a tad more octane boost (probably explains why the oil I got today claims better acceleration times)!

I've read good things about xylene. Lots of hypermilers use a couple ounces to 10gal of gas to boost power and decrease fuel consumption. It can be had cheap in most hardware stores too.
 
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