Fuel for my brand new Kawasaki Vulcan 900 Custom Cruiser?

Question

A couple of weeks I had posted a question regarding advise for a 2007 Honda Shadow Spirit 750 c2 or a 2007 Kawasaki Vulcan 900 Custom. As you see I got the 900 Custom and I think I made the best choice so far. THANK YOU for your advise.



My new question is:
What type of fuel would I need on this new 900 Custom??? On the manual its kind of confusing but I believe it says 90 or higher. This question is not about the money but for the best performance. In my experience the higher octane sometimes made a difference with my vehicles but since this is my first motorcycle then I need your advise again. The last thing I want on my new bike is knocking or some sort of problem. So if 92 or 93 really makes a difference for better then please let me know. Thanks in advance for your advise!

Answer 1

if the manual sez 90 octane, it will run alot smoother, stronger, and better than using the + or 87 octane.

Answer 2

2007 Kawasaki Vulcan 900 Custom

Answer 3

I found mine to be quite comfortable to ride on long trips. My longest trip was 388 miles one-way (roughly 800 miles round-trip) on mainly secondary roads. I spent about 8 hours [all together] on the bike one-way. My 900 Vulcan Classic LT performed like a charm. Better than good power (able to keep up with the "big boys" on the road) and quite economical on mileage (42 mpg average). It doesn t have the acceleration of a big cruiser but it can get you up there pretty pronto. Ride consisted mainly of flat roads with the occasional hill in the road. I guess you can say I am "very" pleased with my 2007 Vulcan 900 Classic LT - - I still have the bike and I have put just over 12,000 miles on it. Plan to keep it for as long as I can ride it - - I m now 60 yrs old and my body is starting to ache more and more. Hope this helps someone out there trying to make up their mind about getting a Vulcan Cruiser.

Answer 4

My recommendation is go with what the factory manual states. I was using nothing but 93 in my Honda Shadow Spirit 1100, but then I looked in the book and it said 86 or higher, so I made adaption and use 89 and the bike shows not difference in performance...bottom line is use what is recommended in your manual.

Answer 5

I have a 06 kawasaki Vulcan 900 classic. I run premium, every motorcycle person or even dealership I have talked to said you should always run premium.
I have never tried to run any other octane through my bike and I am not about to start.
It made a big difference in my first bike, 01 yamaha Vstar 650. when I ran regular in performed very poorly.

Answer 6

There are several methods for calculating octane rating (see the second link below for more details), but the two most commonly-used ones are RON (Research Octane Number) and MON (Motor Octane Number). According to Kawi's specs, the 900 Custom should use "min 91 research / 87 avg" octane fuel. This means gasoline with a minumum RON of 91 and an average octane rating (also known as AKI--Anti Knock Index) of 87. The formula for AKI is RON + MON / 2. Regular-grade unleaded fuel here in the US is almost always AKI 87 with a RON of 92 and a MON of 82, which means it's perfectly fine to use regular unleaded in your 900.

There's a lot of misunderstanding about the role of octane in fuel. Most folks figure it must be "high-power" since A) it's more expensive, and B) racing fuels are high octane. Octane does not give any "kick" to your gas. Actually quite the opposite. Octane retards combustion so that high-compression engines don't blow themselves up. Your 900, like my 800 Drifter, has a compression ratio of 9.5:1. That's not bad, though certainly not super high for a motorcycle these days. Still, a lot of cars with similar compression ratios recommend 92 AKI or better--so why not our bikes? Carbon buildup. Kawasaki's 800 motor is renowned (or infamous) for being prone to carbon buildup in the cylinders. Over time, this fouling can diminish the spark from your plugs, cause ring blow-by and make your exhaust valves stick. You will perceive these problems as a loss of power and fuel efficiency, and eventually you will have to pull the heads to make some expensive repairs. To help alleviate this, Kawi programs their electronic ignition modules to control detonation, allowing riders to run "hotter" fuel than they might otherwise. The 900 motor hasn't been around long enough to develop the same reputation, but since Kawi is giving it the same fuel recommendation as it does for the 800, my guess is they saw carbon buildup in the test rigs and decided to apply the same remedy.

It's ironic that a lot of the people who choose to use higher-octane fuel for performance reasons are actually robbing their engines of power and even potentially damaging them. Basically, if your motor starts pinging, switch to 92. Otherwise, save your money for farkles and doo-dads for your ride, and run regular in your 900.

PS: Aside from the octane-testing link and one to Kawi's spec pages, I've also included a link to VROC (the Vulcan Riders and Owners Club). This internet group has a forum populated by literally thousands of Vulcan riders. Any number of them will be able to provide you with helpful tips on your 900 (just don't start talking politics or religion unless you're wearing your asbestos undies).

Answer 7

Most bikes like premium grade fuel. Run 91 a few times, get to know the bike and the engine. Try one run with 89 and see if it behaves the same way or worse. My Harley likes 89, my Buell likes 89, my husbands Buell likes 91.

Answer 8

Use the good stuff 91+. Usually the higher grade gases at a name brand station has better additives to help keep the fuel system cleaner. Watch out for non-branded gas stations. They usually have dirty gas.

Answer 9

I have a 99 suzuki intruder 800 and my husband has a 87 honda shadow vt1100 and we use 87grade and have never had any problems as of yet(knock on wood)

Answer 10

I suggest following the owner's manual and use 90 octane or higher, especially during the warranty period.