Best Fuel Option - Bronze, Silver, Gold/Premium

[bcrisp]

2002 Katana 600

In terms of performance, is there any material difference to using regular gas such as Bronze (e.g. 87) versus Silver (89) or Gold/Premium (grade 91 or higher)?

I have always used regular gas with all of my motorcycle but if a 87 or higher gives better performance, I would like to hear from the community as a another rider told me that it would improve the performance because the Katana's are carbureted.

[92xjunker]

All katana's are designed to use 87 octane any more is just a waiste of money. Higher octane such as 91 burns to slow and you experience some performance loss, though slight.

[Kat Floyd]

The engine on a Kat was designed to burn 87 octane

[ygolohcysp]

I agree with the others here. If the engine internals are stock, and it's running the with the same compression ratio, there's really no benefit to running the higher grade, unless the higher grade doesn't have ethanol.

[JohnnyPossum]

I'm always running the best gas in my bike cuz thats what I've been told is best for it as well as anything I've seen online corresponds with that, I've never once heard someone say a motorcycle even "could" lose power for running higher octane gas than it was built for.

since I cant find an answer anywhere else online, I have a GSF600S which is very similar to the 600 katana engine.

should I really not use gas above 87?

[Kreylyn]

I'm always running the best gas in my bike cuz thats what I've been told is best for it as well as anything I've seen online corresponds with that, I've never once heard someone say a motorcycle even "could" lose power for running higher octane gas than it was built for.

since I cant find an answer anywhere else online, I have a GSF600S which is very similar to the 600 katana engine.

should I really not use gas above 87?

Timing... the engine is timed... meaning that the pistons compress - the valves open or close - and the spark ignites the fuel all to produce the explosion at a very specific timing....


By default, the US katana is already slight retarded on the timing. It's common to use an ignition advancer to improve performance slightly.


The higher the octane, the more retarded your fuel explosion is going to be. That's what octane does... retards the fuel explosion to compensate for higher compressions.


So you take a time retarded bike to start with, and put higher octane fuel into it so the actual explosion in the chamber is even more retarded...


Yeah...that causes a decrease in performance.


Krey

[KAT TOY]

premium can also make engine run hotter. not good on air cooled engine.

[tbeeler]

Wow I didn't know this. I thought the spec book said 87 or higher. If it really makes a performance loss guess I better start putting cheaper gas in it. Thx for the info.

[ZukiFred]

If you can aford the Gold/Premiumthen I would recomend you not get that and finde a station with nonethinol fuel and spend your money on it instead.

[IanDMacDonald]

If you can aford the Gold/Premiumthen I would recomend you not get that and finde a station with nonethinol fuel and spend your money on it instead.

+1 I treat my bikes to ethanol-free gas once a month from the marina. You'll see a slight boost in fuel mileage as-well.

[Jeckel]

Timing... the engine is timed... meaning that the pistons compress - the valves open or close - and the spark ignites the fuel all to produce the explosion at a very specific timing....


By default, the US katana is already slight retarded on the timing. It's common to use an ignition advancer to improve performance slightly.


The higher the octane, the more retarded your fuel explosion is going to be. That's what octane does... retards the fuel explosion to compensate for higher compressions.


So you take a time retarded bike to start with, and put higher octane fuel into it so the actual explosion in the chamber is even more retarded...


Yeah...that causes a decrease in performance.


Krey

I'm a little confused by this. In my limited tuning experience, the higher the octane, the slower the burn, the more advance you can set your timing. more timing = more power.

This is based on forced induction fuel injected car tho, and not N/A carbed inline 4. Can you help me understand what your saying?

[TheBlack7]

I'm a little confused by this. In my limited tuning experience, the higher the octane, the slower the burn, the more advance you can set your timing. more timing = more power.

This is based on forced induction fuel injected car tho, and not N/A carbed inline 4. Can you help me understand what your saying?

The Katana is set up to run on 87 octane. It's true that forced induction car's can benefit from higher octane because it allows more advanced timing because the higher the octane rating the more resistant the fuel will be to detonation (ignition of the fuel before spark). It allows boosted cars to increase boost/run higher compression without the danger of detonation (to a greater extent). This goes for an N/a engine like the Katana's too except obviously being setup for 87 octane means the compression ratio/timing isn't aggressive enough to warrant use of a higher octane. Granted it would allow you to run more aggressive (advanced) timing safely

[Jeckel]

The Katana is set up to run on 87 octane. It's true that forced induction car's can benefit from higher octane because it allows more advanced timing because the higher the octane rating the more resistant the fuel will be to detonation (ignition of the fuel before spark). It allows boosted cars to increase boost/run higher compression without the danger of detonation (to a greater extent). This goes for an N/a engine like the Katana's too except obviously being setup for 87 octane means the compression ratio/timing isn't aggressive enough to warrant use of a higher octane. Granted it would allow you to run more aggressive (advanced) timing safely

Makes sense. I have seen some threads here about a "spark advancer" (or something) would that benefit from higher octane?

[cintidude04]

Makes sense. I have seen some threads here about a "spark advancer" (or something) would that benefit from higher octane?

I haven't heard of a spark advancer, per se, but my guess is you're referring to the timing advancer for the Kat?
Even with the 5 degree advancer, along with many other mods, I still ran 87.
There is zero reason to run more than 87 octane.... Unless it's all you can find that's ethanol free, you've increased your compression, or you've built a custom gsxf engine etc etc etc

[KAT TOY]

try this http://katriders.com/vb/showthread.php?t=51277