[bman734]

Make sure you don't fill up when there is a replenishing  tanker there. They will stir up any crap that may be in the tank. By the way regarding high octane, my mechanic friend doesn't  even understand why we wouldn't use high test since we are already getting 75 mpg and so the extra .80 cents it would cost to fill a tank is good insurance. His bottom line argument is always, "it can't hurt after all". I will be interested if my mpg's improve. I have been getting a consistent  78 mpg on regular gas.

[singhg5]

I will be interested if my mpg's improve. I have been getting a consistent  78 mpg on regular gas.

High octane does not improve miles per gallon.

[Ice]

I agree for the most part now a days.

 
 Only in cars with fully computer managed engines have I seen in increase in fuel economy with premium in the tank.

 Example my moms car with the north star V-8. The ECU controls both the ignition and EFI. It continuously adjusts mixture, advances timing and adjust timing curve to optimal settings based on the feed back from at least a shoe box full of sensors. Each cylinder has it its own knock sensor I do believe and there are at least two O2 sensors on board.

 

[bman734]

Had it out today, with the high octane gas, and it just seemed to have a wee bit more pep and pop. I know, this is most likely  all in my mind, and it probably is, buy I'll take a subliminal placebo effect improvement cause it make me feel better, kind of like a sugar pill.

[Ducati Scotty]

I find most of my bikes have run a bit smoother on premium but there was no noticeable power increase.

Scott

[Arizoni]

It's a good thing the Royal Enfield's don't have a knock sensor.

All of the normal "ticks" and "tacks" and "clicks" and "clacks" would drive it out of its mind. 

[GlennF]

It's a good thing the Royal Enfield's don't have a knock sensor.

All of the normal "ticks" and "tacks" and "clicks" and "clacks" would drive it out of its mind. 

Actually Enfields have always kind of remind me of the old Pratt and Whitneys and Wright Cyclones in aviation ...

http://youtu.be/EkcX0KGIBwk

[Arizoni]

I really get a kick out of watching that radial firing up.
It almost sounds like it has a Royal Enfield sprag clutch in it.  

Then, there's this DC 3.
The right engine had just been rebuilt so you guys with the rebuilt RE's who are having problems getting it to light off, pay attention.
http://www.youtube.com/watch?v=9QyHw408CtU&feature=endscreen&NR=1

And for seeing some Really BIG radials start, this B-29 is interesting
http://www.youtube.com/watch?v=yAf6GScjiHo&feature=related

[hillntx]

I use premium in all my parade bikes and my street bike.  With our 100+ degree summer temps, they just seem to run better.  Considering the great fuel economy of these RE's what's an additional dollar per tank?

[Ducati Scotty]

Premium will usually burn cooler.

[Ice]

I find most of my bikes have run a bit smoother on premium but there was no noticeable power increase.

Scott

This is my experience as well.  They also start easier and idle steadier.

 The chemicals used as oxygenates, fillers and extenders lower the octane so there is less of them used in mid grade and premium.

[ROVERMAN]

Remember that mid grade doesn't exist until mixed at the pump. Also premium fuel has lower volatility, which isn't much of an issue except during the fall and spring changeover from summer/winter blending which causes havoc on the new direct injection vehicles. .

[saint45]

Ive always run premium in every bike ive had. BTW...unplugged the side stand "dummy" feature and bike is running like normal...still a bit more backfire than expected since i put the EFI pipe on. Should i have to change the FI mapping? or spark plug? anything?

[trimleyman]

saint45:

Another thing to consider if you have not already done it is to disconnect the side stand safety switch.

If the switch is slightly defective or if the side stand is moving up and down as you ride it can cause the computer to decide the side stand is down.
This will temporary kill all electrical power to the ignition.

The wiring connector for this side stand switch is located on the frame on the left side right behind the engine.

Unplugging the connector will disable the switch.

Warning:  With this switch disconnected, the motorcycle will start and run normally even though the side stand is left down.
If the side  stand is left down and you ride off of a fast drop off (like a curb) the stand will hit the ground and high side you off the right side of the bike.

Also, in my opinion, it is not a good idea to run the engine with the bike resting on the side stand. 
Most of the oil will be over in the left side case so there is a possibility of the oil pickup tube sucking air into the lube pump.

Figuring this switch was just another safety device that could fail at a moments notice and I could live without that sort of problem I disconnected mine several months ago.

So far I have made it a point to always raise the side stand before I turn on the key to start the bike so my bike hasn't been down yet.

My G5 quit of the San Mateo Bridge on the way to Monroe Motors last year to have the speedo drive replaced. Kicked down the side stand kicked it up again and it restarted fine. Had Monroe guys disconnect it. The said they would see if it could be replaced under warranty , but have not had any further news from them on the subject. It has never given trouble since. So have left well alone.

[Desi Bike]

I run my C5 on 94 octane, or at least try to.  0% ethanol for my local pumps on premium and up.

 The fuel that is left in the fuel pump hose at the station from the selector to the hose end you stick in the tank has what ever the previous customer pumped. The longer the hose is, the less of what you actually selected to pump you get. Its a crap shoot as to what is in the hose.