Proposal to delete rule 24.2.1 - Alcohol based fuel or fuel additives are prohibited

[jasonu]

Sure in F4 2T there is a capacity advantage but with fundamental tuning restrictions on the 125. Can you name them?

Not sure what you are getting at but if you mean 24mm carb and aircooled for 125cc 2T. You and others still managed to get 30hp+ with these restrictions. IMO if you aimed for around 25hp you would easily gain mid range hp, rideability and reliability

[jasonu]

Funnest thread in ages.

Lighten up boys. Go to the gym and you will go faster. Get your spring rates right and you will go way faster. Turn the throttle quicker and you might crash. Wisdom right there.

Not to mention a lot of Buckets need to go on a diet too.

[mr bucketracer]

Funnest thread in ages.

Lighten up boys. Go to the gym and you will go faster. Get your spring rates right and you will go way faster. Turn the throttle quicker and you might crash. Wisdom right there.

or give the bike to a young fast rider and sit back and drink

[F5 Dave]

Sure in F4 2T there is a capacity advantage but with fundamental tuning restrictions on the 125. Can you name them?

I think you'll find Jason had some input at the time they were proposed. It was just 100s and 125 foul strokers back when.

[TZ350]

... 24mm carb and aircooled for 125cc 2T ...

And old fat bastard rider ....



I have recently found that when I finally got good at building interesting bikes I am to old to ride them well ....

[husaberg]

I had a look on the net for some SAE papers
http://papers.sae.org/2012-01-1275/

Gasoline/ethanol fuel blends have significant synergies with Spark Ignited Direct Injected (SI DI) engines. The higher latent heat of vaporization of ethanol increases charge cooling due to fuel evaporation and thus improves knock onset limits and efficiency. Realizing these benefits, however, can be challenging due to the finite time available for fuel evaporation and mixing. A methodology was developed to quantify how much in-cylinder charge cooling takes place in an engine for different gasoline/ethanol blends.
........................
The measured charge cooling increases with fuel ethanol content from 14 degrees C for gasoline to 49 degrees C for E85 (85% ethanol, 15% gasoline by volume). The amount of charge cooling as a fraction of the thermodynamic maximum was around 70% for all fuel blends.

[kel]

I had a look on the net for some SAE papers
http://papers.sae.org/2012-01-1275/

Have you read chapter10 and Appendix E? If so you'd know the E85 argument is redundant so how about you contribute something worthwhile and show us the figures for E10?

[jasonu]

I think you'll find Jason had some input at the time they were proposed. It was just 100s and 125 foul strokers back when.

No mate original idea with Chris Pickett, me and SpeedPro was 100h20 2T, 125AC(for TF125 etc) 2T with 24mm carb and 145 (for GL145) diesels

[TZ350]

I had a look on the net for some SAE papers
http://papers.sae.org/2012-01-1275/

I see from the preface they are basically comparing charge cooling between Port Fuel Injection (PFI) with Direct Injection (DI) of five gasoline/ethanol blends. The results showed superior charge cooling with DI compared to PFI for the same fuel blend.

There was no power comparison only that DI proved better than PFI whatever the fuel mix for detonation suppression through superior charge cooling.

As you know the rules ban Methanol outright and appendix E would limit everyone to a maximum of 10% Ethanol.

Detonation suppression is not the same as making power. I would love to see a power comparison between the base petrol and the ethanol blends.

My pick would be that the lower ethanol blends will produce less power as the petrol would need to be run rich to suppress lean burn detonation of the ethanol. And that the power output would be restored as the ethanol volume went up and petrol became the minor component.

I see there are two papers, if your getting them I would be very interested in reading them.

[husaberg]

I see from the preface they are basically comparing charge cooling between Port Fuel Injection (PFI) with Direct Injection (DI) of five gasoline/ethanol blends. The results showed superior charge cooling with DI compared to PFI for the same fuel blend.

There was no power comparison only that DI proved better than PFI whatever the fuel mix for detonation suppression through superior charge cooling.

As you know the rules ban Methanol outright and appendix E would limit everyone to a maximum of 10% Ethanol.

Detonation suppression is not the same as making power. I would love to see a power comparison between the base petrol and the ethanol blends.

My pick would be that the lower ethanol blends will produce less power as the petrol would need to be run rich to suppress lean burn detonation of the ethanol. And that the power output would be restored as the ethanol volume went up and petrol became the minor component.

I see there are two papers, if your getting them I would be very interested in reading them.

Nah i just looked to see the what there was in relation to "cooling and Ethanol based fuels"

The measured charge cooling increases with fuel ethanol content from 14 degrees C for gasoline to 49 degrees C for E85 (85% ethanol, 15% gasoline by volume). The amount of charge cooling as a fraction of the thermodynamic maximum was around 70% for all fuel blends.

As you see there is a rather large cooling effect of the intake charge with an ethanol blended fuel.
Re the methanol, correct me if i am wrong, but i don't recall that i mentioned methanol in this thread?

[kel]

As you see there is a rather large cooling effect of the intake charge with an ethanol blended fuel.

Blah blah blah, ignoring facts and relevant fuel options as they would just get in the way of a good
Go spend some time in the shed building a bike you can race.

[husaberg]

Blah blah blah, ignoring facts and relevant fuel options as they would just get in the way of a good
Go spend some time in the shed building a bike you can race.

Kel anyone who reads this thread will see you can not put up any arguements...... you just argue.... feel free to play the ball.....
you have not put anything to prove your point, that it is not an beneficial advantage for an aircooled 125 2 stroke.
your continued ranting =.

[kel]

Kel anyone who reads this thread will see you can not put up any arguements...... you just argue.... feel free to play the ball.....
you have not put anything to prove your point, that it is not an beneficial advantage for an aircooled 125 2 stroke.
your continued ranting =.

Oh man that put me in my place :
Hows that bike going.

[mr bucketracer]

i have dynoed lots of speedway bikes in the past , they take for ever to heat up like 8 or so mins before you can even dyno the dam things . if its the same in a 2 stroke it's a big advantage . i recond a aircooled 2 stroke lose's 3 hp in 5-6 laps before it stays the same so is more even with the best of the best 4 stroke . 100 water cooled 2 stroke would have to be the best way to go out side that ... just what what i think. 10% Alc is a wast of time but 50%+ would be i think a big advantage . end of the day you still have to ride fast ...we all know my problem so until i fix that i don't care what you do

[husaberg]

Oh man that put me in my place :
Hows that bike going.

It was a polite remember that this is a debate, to which you again put nothing forward to prove it does not provide a beneficial advantage for a 2 stroke air cooled 125............
The bucket will be finished with it home cast cylinder and most likely a new set of cases as well, target is October 2014.