so a buddy and i go to a track day a few weeks ago and he tells me he is running av gas...(100 low lead)....im pretty sure he has a map for pump gas....would that hinder him at all....or is he just wasting his money on av gas
pretty much wasting money more than likely. Av gas basically as far as I knwo is just a different octane, or resistance to detonation. Him running it, i is not much different than running premium in a 600 tuned for 87. The benefit is almost nill.
if his bike is a late model with a catalyzed exhaust & an O2 sensor, even minor amounts of lead can cause damage.
I wouldn't use any AVGAS on a motorcycle, the tetra-ethyl lead contained in 100ll will mess with the Catalytic converter, o2 sensor, and possibly the injectors. Not to mention lead fouling on the plugs.
who has a converter on a bike? i didnt even get a chance to change mine, when i bought the bike i told them to change the exhaust before shipping it to me, i've never had any bike with a stock exhaust much less a converter, you can run a very long time with 100LL before you do anything remotely bad to an o2 sensor remember 100LL is about the most no screwed with fuel out there aside from vp, sunoco, and other brands of racing fuel, they dont put ethanol in it, its pretty much the same as it was years ago
Do not use av fuel. When I first got my pilots lic I tried to run av fuel in my bike. Didnt work. Why? Av fuel is desighned to run at a a low specific rpm for long periods of time. Our bikes run at very high rpms for short bursts. Also the specific gravaty of 100LL works out to ne some where around 82 motor oct. If your gona spend money on fuel buy the correct stuff or just run prem fuel.
Yeah, 100LL in the bike is not a good idea at all. As mentioned before lead fouling of the plugs, O2 sensor is a big problem. Plus it will destroy the Cat in no time. Also, higher octane fuels have a lower energy content than an equivalent lower octane fuel because of the anti-knock additives. If you can get ethanol-free 91-93 you will produce more power than with 100LL. The only reason to run a higher than recommended octane fuel is if you have increased the compression ratio or compression pressure. Aircraft engines that use 100LL are air-cooled and need the extra anti-knock margin for high power continuous operation with the less than ideal cooling of the head and cyl barrel. Most of the normally aspirated aircraft engines run fine on premium auto fuel, but the ethanol they are adding these days does not work well. Another FYI, the fancy full-synthetic oils we use in our bikes are not able to properly scavenge lead in the engine and will lead to lead-fouling of oil passageways, bearing, ect possibly leading to premature engine failure. Aircraft piston engines stick with mineral-based (some semi-synthetic) oils for this reason. I'm also a pilot, aircraft mechanic, and might have slept in a holiday inn express last night..haha
used 100LL for many years on an engine that shouldn't run 91 octane even to idle around the block....knocked like mad. 100LL is not 82 octane. obviously trackday dude doesn't need it for compression reasons. but to say your bike is going to explode when you pour it in is a stretch. lead fouling of oil passages ? i gotta see a pic of that. who are you guys helping if you are posting 3rd hand misinformation ? sheesh.
Thanks for your excellent contribution No one here said anything about exploding bikes. If anyone knows something about Avgas, it's going to be an A&P mechanic on this forum. And if 100LL was 100 octane, unless you advance the timing to compensate for the slower and cooler burning of fuel, this could lead to incomplete burning of fuel in the power cycle resulting in deposits in the combustion chamber.
I was considering running AVGAS this year and now you've got me second guessing it. My ZX10 has a high comp motor with altered timing. The guy who built it apparently raced it on 110 leaded fuel. It runs fine on 94 pump but I figured AVGAS would be better for it and a cheaper alternative to race gas. There's no cat, and when I had the plugs out recently to check them out they were just fine. The bike actually runs very smooth and strong on AVGAS. Is it bad to leave in a bike between rounds? I've got some friends who've been running it and as far as I know not experienced any of the problems listed in this thread.
i guess it's important to consider where you get your advice. http://www.r6-forum.com/forums/showthread.php?t=123487&page=3
As a pilot and internet expert I can assure you that 100LL is WAY more than 82 octane. And octane has NOTHING to do with energy content or specific gravity?????? My airplane runs great on 91 premium if it can be found without ETOH but that's damn near impossible. 100LL has considerably more octane than 91, I just don't need it for my engine. 100LL has I believe a RON of 130 octane. This citation shows test performance from 99 to 130 depending on the 2 test methods, lean and rich. Can't remember how this translates exactly to the ron/mon were used to with pump gas. So I don't know where 82 came from in the other post. http://www.experimentalaircraft.info/homebuilt-aircraft/aviation-fuel-avgas-specs.php http://en.wikipedia.org/wiki/Octane_rating As to oil passage contamination with lead, I'd love some proof of this. Not saying it couldn't happen, but when these bike engines lifespan consists of a few thousand miles and a couple hundred gallons of fuel I'd be surprised if it happened that fast. with just 2gm lead per gallon and most of that going out the tail pipe, lead accumulation in the oil would be minuscule. To the OP, if you don't NEED race gas you don't need avgas. Might be fun to run some dyno on both pump and avgas. Get some real data instead of internet conjecture. I'd be amazed if there was a statistical difference in the two.
Just to add, "low lead" is relative to the old "high lead" aircraft used in the past and has significantly more lead that auto fuel ever had. When the feds wanted to strip the lead from gas the Av industry informed them that planes would fall from the sky. The vast majority of small aircraft engines where technically not much more than fancy VW bug aircooled motors and ran at high load for hours. The valve train really needed the lead for cooling and lubrication. The removed some lead to appease the Feds, but there is still alot in it. I kinda think this all goes back to where do you want to save money? I've known plenty of guys over the years that have cheaper ways to do things. Black pepper is a great radiator stop leak. Yea, and I can buy good stuff for $3. So you make a choice. Buy Av gas and play with timing, compression, various adjustments and oils and hope you get it all right. The other option is using the race gas that is specified for your build (CR, timing, etc) and spend an extra $100 a year? If somehow there was some secret HP to be found in playing with Av gas, maybe I would experiment. To save a few bucks, I think it would be only second to oil in places I'd want to experiment. BTW,don't use higher octane than you need, will slow you, but that's a whole 'nuther thread!
As far as leaving it in the bike, all I can say is Avgas is extremely stable and unlikely to varnish in storage. When other pilots bitch about running pump gas, lack of stability in Pump gas is always #1 on their list of complaints. The nature of aviation frequently includes very long periods of inactivity and the fuel has to deal with this adequately. Avgas is also less likely to attack seals and rubber in the fuel system, this is complaint #2 regarding pump gas in planes and I believe primarily has to do with ETOH in pump gas.
I've used 100LL many times in my race bike and my tow vehicle. Obviously neither of them have catalytic converters and they both run fine. Aside from race gas it is the only way to avoid e10 in my area and I get it free on occasion from work. My bike has a noticeable increase in power with 100LL vs. E10. The only draw back I've found is it is far more susceptible to vapor locking then summer blend pump gas, but so far thats only an issue in my pickup when the A/C is running at a stop light. I do love the stench of 100LL at a stop light
Strange? Complaint #3 about pump gas vs avgas is higher vapor pressure (boils easier) of pump gas that leads to MORE tendency to vapor lock at altitude.
Im not saying your bike is gona explode im just going off me experiance and from being a pilot with many friends being a&p's telling me its a bad idea. I just dont see why you want to spend 10g on a bike n put fuel in it thats not correct. This is just my openion. Its your bikes n your repair bill.
