Do GSXR's like Av Gas??

[BUBBLE]

I've got a few litres of Avgas in the shed and was wondering if anyone has had problems running a standard GSXR600K3 (fuel injected) on Avgas. I've run bikes in the past with 100% Avgas with no modifications and no problems. My only concern is if the fuel injected GSXR's have a Oxygen Sensor because I know that with some cars, Oxygen Sensors can be damaged with using Leaded Fuel.

[Drunken Monkey]

I've used pump race fuel, which is apparently aviation fuel past its use-by, without any problems.

[bugjuice]

I've used pump race fuel, which is apparently aviation fuel past its use-by, without any problems.
I saw some of that at the Challenge gas station down the road from Puke track - at $2 a litre!

[curious george]

Why on earth would you want to? Cos you want to go slower?
The fumes from av gas are pretty corrosive, and might eat a bit of your exhaust unless it's stainless...

[bungbung]

I saw some of that at the Challenge gas station down the road from Puke track - at $2 a litre!

$2!, captive audience innit?

AvGas from Welli flying club was $1.40 recently.

[BNZ]

Why on earth would you want to? Cos you want to go slower?

Huh? How is AvGas going to make you go slower? Im pretty sure hes not talking about JET-A1!!

[Motoracer]

Huh? How is AvGas going to make you go slower? Im pretty sure hes not talking about JET-A1!!

Cos the higher the Octane the slower the fuel burns. If your engine isn't highly tuned, AvGas doesn't make a diff. Infact running 91 or 96 would probably make it go faster. Just cause the higher octane fuel burns slower, it is more stable so for highly tuned engines it is a safer way to go. If you run 91 on a top of the line race machine, there's a good chance that there will be a lot of detonations from over heating, thus damaging vital engine parts in the process. If you check the temp gauge, the engine would be running at a much higher temp it self. When you run AvGas, it just burns slower to help keep things cool and calm so that the engine can perform like the way it was tuned for.

[bugjuice]

Cos the higher the Octane the slower the fuel burns. If your engine isn't highly tuned, AvGas doesn't make a diff. Infact running 91 or 96 would probably make it go faster. Just cause the higher octane fuel burns slower, it is more stable so for highly tuned engines it is a safer way to go. If you run 91 on a top of the line race machine, there's a good chance that there will be a lot of detonations from over heating, thus damaging vital engine parts in the process. If you check the temp gauge, the engine would be running at a much higher temp it self. When you run AvGas, it just burns slower to help keep things cool and calm so that the engine can perform like the way it was tuned for.
so av-gas would suit newer engines like bikes designed after y2k?
The other thing I've heard is that high octane fuels increase 'knocking' in engines. Not sure if knocking is a bad thing or not, but doesn't sound all that great..

[vifferman]

so av-gas would suit newer engines like bikes designed after y2k?
The other thing I've heard is that high octane fuels increase 'knocking' in engines. Not sure if knocking is a bad thing or not, but doesn't sound all that great..
No, that's back to front. It should decrease knocking, due to the higher octane rating.

Bubble: If the GSXRXRRR has O2 sensors, you should be able to see them, plugged into either the first part of the muffler, or just before the can.

[bugjuice]

No, that's back to front. It should decrease knocking, due to the higher octane rating.
ahhhhhhhhhhhhhhhh.. gotcha.
then my engine is fukt.
bugga.

[vifferman]

then my engine is fukt.
bugga.
How so?
You had some serious knocking noises from it?

[bugjuice]

How so?
You had some serious knocking noises from it?
ahhh.. it's more of a pt than serious at the moment. I've been told all kawa 600 engines from these bikes get knocky. I thought it was a problem, but 2 kawa mechs have told me to suck it up and ride the bloody thing. Just sometimes I could scare tractors and that's before the exhaust note..

[Zapf]

ahhh.. it's more of a pt than serious at the moment. I've been told all kawa 600 engines from these bikes get knocky. I thought it was a problem, but 2 kawa mechs have told me to suck it up and ride the bloody thing. Just sometimes I could scare tractors and that's before the exhaust note..

could be something to do with their very high compression... like 12.9:1 for their 05 636.

[bugjuice]

could be something to do with their very high compression... like 12.9:1 for their 05 636.
could be.. think the 03/4's are 12.8:1

[Wenier]

I have run mine on 100% Av-Gas for a couple of tanks and it went fine, i dont no much bout the O2 Sensor in it but the lead from the fuel can clog em and stuff which means youll need another, obviously it would take more Av-gas than you've got in ya shed. Also it smells great and ya get the lead around the inside tip of the exhaust instead of the black carbon colour so is quite cool.


Huh? How is AvGas going to make you go slower? Im pretty sure hes not talking about JET-A1!!

No.1 We'll get this straight JET-A1 is NOT AV-GAS, it is AV-TUR!

And Vifferman is correct it decreases the chance of knocking, or detonation by being a higher octane.

No.2 AV-GAS is a rating of 110/130 octane, this means at different operating temperatures it operates at the characteristics of either 110 or 130. Cant remember which one it acts as for cold or hot thou.

And i am pretty sure it doesnt burns slower so you should either find no difference in performance apart from the engine might run a bit smoother.

This is as unless you change the fuel ratio to either side of perfect it should burn jus as fast if not quicker. I also Av-gas is able to help in cooling if you have correct valve overlap.

[Zapf]

Av gas burns slower hence lower pressure from the burn. lower pressure = less power...

so run the lowest octane that is suitable for your engine...

question is, how do u know if ur engine is knocking....

[Wenier]

You'd usually hear it.

Pressure should be the same thou as the fuel injection is still going to pump say 1 part fuel (wut eva the octane) to 14 parts air. That probably isnt the ratio for bikes but i cant remember. If you change the ratio it will burn slower. This would then give you less power as the time when it is all burnt and has the greatest pressure to act on the piston is after the Most effective crank angle. But if the ratio is the same the burn speed should still be 100ft per sec and it should still have the same amount of pressure at the correct time.

If it were slower i should have felt a difference in my bike when i did it which it didnt. Infact the bike seemed to run with no change in performance.

[bugjuice]

Av gas burns slower hence lower pressure from the burn. lower pressure = less power...

so run the lowest octane that is suitable for your engine...

question is, how do u know if ur engine is knocking....
I thought the idea was to run a higher octane to get the hotter burn which would produce the better power?
What would the point of running AvGas in race cars etc be if it produced less power?

as for the knocking, you hear a metal 'tinging' sound, or a knocking, like something is loose, but it isn't..

[Wenier]

I thought the idea was to run a higher octane to get the hotter burn which would produce the better power?
What would the point of running AvGas in race cars etc be if it produced less power?

as for the knocking, you hear a metal 'tinging' sound, or a knocking, like something is loose, but it isn't..

Thats exactly the same idea and im sure it burns the same or faster. Also Av-gas has TEL (ethylene Dibromide) mixed with the fuel to get rid of lead residue by combining TEL with the Lead to form Lead Bromides (these are volatile) which can be sucked out with exhaust gases instead of forming solids so that could bring down the chance of fouling the O2 sensor.

[Wenier]

shit almost forgot. 110/130 runs at 110 when your engine management computer is running the engine lean, or 130 when it is running it rich.

[Ixion]

I thought the idea was to run a higher octane to get the hotter burn which would produce the better power?
What would the point of running AvGas in race cars etc be if it produced less power?

as for the knocking, you hear a metal 'tinging' sound, or a knocking, like something is loose, but it isn't..

Slower burn means you can up your compression ratio without detonation. Or use a higher turbo boost pressure . Same deal as alcohol basically, the fuel itself doesn't give any more power, but means you can tune the engine higher without it self destructing. (alcohol's a bit different though because it has it's own oxy supply)

[bugjuice]

Slower burn means you can up your compression ratio without detonation. Or use a higher turbo boost pressure . Same deal as alcohol basically, the fuel itself doesn't give any more power, but means you can tune the engine higher without it self destructing. (alcohol's a bit different though because it has it's own oxy supply)
ahhhh.. explains a bit..
Alky would be different anyway - too many riders would be going around with a straw in the tank.. :drinknsin

[Zapf]

ok... guess like some people know more than I :)

but from my experience from a 2.5L hi compression turbo motor, is that stock engines can't really benfit much from running av gas. to really benfit from av gas, engine (head / piston) modifications are usually required.

Engine management can't benfit much either, except some ign timing.

[Ixion]

ok... guess like some people know more than I :)

but from my experience from a 2.5L hi compression turbo motor, is that stock engines can't really benfit much from running av gas. to really benfit from av gas, engine (head / piston) modifications are usually required.

Engine management can't benfit much either, except some ign timing.

Yes. Though the other way round really. To use hairy levels of head/piston mods or silly boost pressures, you need to use avgas or it all goes bang tinkle. If you're on stock top end, avgas won't give any advantage . May even reduce power as someone said below.

[Rod Steel]

So then if this is all correct that means my dad is lying? when he claimed that he used to get upto 140km/ph on his honda 100 when he was in his teens? He did also claim he blew the head gasket and put holes in the piston reguarly(sp?)...

[MSTRS]

So then if this is all correct that means my dad is lying? when he claimed that he used to get upto 140km/ph on his honda 100 when he was in his teens? He did also claim he blew the head gasket and put holes in the piston reguarly(sp?)...
Honda 100's were faster in the olden days cos the fuel was fresher back then :killingme

[oldfart]

well all I can say to all this very erudite & knowledgable information is "Bah Humbug". You guys could fertilise a nation. All I know is when I ran my old Kwaka Z1, (1973), on AV gas, it went noticeably faster, ran cleaner etc etc. Not sure how modern motors appreaciate leaded fuel but.

[Sensei]

Ran 30% avgas in my GSXR1100R WP at the drags and would do 10.20 1/4's .
Without Avgas 10.70 sec 1/4's
SENSEI

[Ixion]

So then if this is all correct that means my dad is lying? when he claimed that he used to get upto 140km/ph on his honda 100 when he was in his teens? He did also claim he blew the head gasket and put holes in the piston reguarly(sp?)...

Well at 140 it would be way way way over the redline. But those Honda speedos were the biggest fairy tale tellers since the Messrs Grimm. So I would maybe believe a true 110-120, downhill , indicated as "needle swinging wildly back and forth off the end of the speedo scale so maybe that's 140kph"

I used to see 130 on my 125. Downhill, tail wind tacho in the red, me in the tank. Bent a valve, but nothing worse,

Got a Beezer Bantam up to 65mph too, bu that was highly hacked about

[Wenier]

It definitely gives more power rather than less, if ya get less theres gotta be something wrong.

[inlinefour]

Have not found a motor that run really well for a shortish time on avgas. Killed t it though :msn-wink:

[speedpro]

More energy can be liberated from fuel if it is compressed prior to ignition. More compression = more power. Unfortunately there is a limit, beyond which detonation destroys the engine. Some fuels resist detonation more than others. In order they would be 91 - 100 - methanol. 100 octane may burn slower than 91 but that isn't the factor that's important as it is a miniscule differance. The important point is that 100 octane, and more so methanol, resist detonation more than 91 octane and this allows higher compression.

The whole process is compression, ignition-flame front moving away from the plug across the chamber, pressure and temperature rising. If the temp and pressure rise enough before the flame front consumes all the fuel it is possible that the remaining fuel could spontaneously ignite. That is detonation and it causes a very 'sharp' increase in combustion chamber pressure and temp.

There's lots more to it, like the chemical changes that occur to the fuel as the pressure and temperature rise and the resultant changes in burn characteristics. One point that a lot of people missed with the change to unleaded is that although the old 96 octane fuel had benzene in it, that benzene didn't make it out the exhaust pipe. The new ULP doesn't have benzene in it but a by-product of burning it is benzene. Unless vehicles using it have a (working) catalytic converter that benzene goes out the exhaust. Benzene is highly carcinogenic.

Geez I hope that's right. Could someone please let me know if I got it wrong.

[DEATH_INC.]

You WILL get a reduction in power with higher octane fuel IF your engine doesn't need it.It may only be points of a hp but it will be there.The psychological benefits may outweigh this however,so just keep on putting it in if you must......
It does burn slower(do a search for info,it's out there),so think about it,the piston has travelled further down the bore before complete combustion,so you don't get maximun pressure.
If you want an easy power increase go with oxygenated race fuel....