• Husqvarna Motorcycles Made In Sweden - About 1988 and older

  • Hi everyone,

    As you all know, Coffee (Dean) passed away a couple of years ago. I am Dean's ex-wife's husband and happen to have spent my career in tech. Over the years, I occasionally helped Dean with various tech issues.

    When he passed, I worked with his kids to gather the necessary credentials to keep this site running. Since then (and for however long they worked with Coffee), Woodschick and Dirtdame have been maintaining the site and covering the costs. Without their hard work and financial support, CafeHusky would have been lost.

    Over the past couple of weeks, I’ve been working to migrate the site to a free cloud compute instance so that Woodschick and Dirtdame no longer have to fund it. At the same time, I’ve updated the site to a current version of XenForo (the discussion software it runs on). The previous version was outdated and no longer supported.

    Unfortunately, the new software version doesn’t support importing the old site’s styles, so for now, you’ll see the XenForo default style. This may change over time.

    Coffee didn’t document the work he did on the site, so I’ve been digging through the old setup to understand how everything was running. There may still be things I’ve missed. One known issue is that email functionality is not yet working on the new site, but I hope to resolve this over time.

    Thanks for your patience and support!

Question about octane levels in gas

M

Mike758

Husqvarna
B Class
So I have a 1987 Husqvarna 430 AE. In the manual it says to only use 95 octane gas. I live in the United States, and the highest level of octane I can get in gas stations around me is premium gas, which is 91-93 octane. I've never had a dirt bike with such a high octane requirement, so I'm wondering how critical this is to match the 95 octane level, and if it is important, where can I find this gas?
 
We are lucky (ish) in the UK as our standard gas is 95 octane. Super unleaded is 97. But the issue is, that the stuff is full of ethanol and other crap. My Husky 390 hates the stuff, the CCM pinks like Lady Penelope's Rolls, and the "tweaked" KLX250 twin shock has even less power than my lawn mower.
I use 114 octane leaded race fuel from Sunoco and mix it 20% with pump gas. Cured all my problems :)

I can't point you to where to get regular gas that is better, but maybe adding race fuel will help. I have found that 2 strokes don't like unleaded fuel.
 
Here's the deal: Ethanol lowers the octane rating in gas. The higher the octane, the slower the gas is to combust. That's why low octane gas is a no-no with high performance engines running with a lot of ignition advance...the fuel will ignite too soon and cause knocking. If you can't find higher octane gas to slow down the burn rate, then your other option is to de-tune a bit....i.e., retard your timing somewhat. You probably won't even feel the difference in performance unless you're a die hard racer, but your engine will feel better.
 
(R+M)/2 octane ratings.
You have to compare apples to apples. What does the manual call for RON octane?
I do get race gas on occasion but more for the lead, I hate the smell of a lot of race gas. I don't see a need for anything but premium from a knocking standpoint. Chain slap can be mistaken for knocking. I thought ethanol raised octane, certainly to run methanol higher compression is used. If you can find ethanol free gas might as well use that. http://pure-gas.org/
 
I don't know, it's hard to tell because it doesn't specify in it's RON or not, and says min. 95 Octane in both the English and Swedish. If you want to take a peek for yourself it's on the last page: http://www.yourhusky.com/files/86-88-Auto-shop-manual.pdf

But I figured though regardless some guys may be able to tell me whether or not that's the right number. This is my first "real" bike as my bikes in the past (Kawasaki KDX 250 and Yamaha TTR 125) were just beat up bikes worth less than $200. I also had a CZ 125 but it was seized up. So I don't know too much about bikes yet, that's why I'm referring back to this page and getting help from friends
 
OOPS, my mistake kids. Don't know how my mind got so warped, but ethanol does indeed raise the octane level - not lower it as I previously said. It doesn't raise it a lot, something like 2 to 3 points is all, but in so doing it slows down the combustion process to allow for more compression and/or timing.
That's all fine and good, but the whole intent of the original question was about finding 95+ octane gas. Without the ethanol, we would be hard pressed to find even 89 octane in the US anyway. I think 92 is all I can find locally.

Back in the days before we got on this burnable cocktail kick, they used to add stuff like xylene (I think) and other exotic chemicals to raise the octane way up. It seems that 98 octane "premium" gas was readily available everywhere when lead was still being used.

So again, if engine knocking is a problem about all you can do it back off the timing.
 
stormer254 said:
Mix in a bit of Avgas
Click to expand...

If only they sold Avgas at my local Walmart. The nearest small airport is 50 miles away, and I don't even know if they have or will sell me Avgas. Too much of a pain in the ass when all my bikes run fine (enough) off crappy pump gas.
 
I ordered my 25 litres of 115 Octane Leaded race gas on Friday. It arrived here at work yesterday ! I didn't even have to break into a sweat to get it.
Just go onto the Sunoco Race Fuels web site and order !
 
A 25 litre drum will last me almost a season. There seems to be no degradation during this time. At the 20% I mix it with super unleaded there is enough for 125 litres of std gas. That is 150 litres total.
 
I have had a 87 430CR & currently have a 88 430WR. I Have run them many years with no ill effect on 93-91 octane.
 
Hey Guys,
I am no expert, from my experience the ethanol/gas eats at any rubber type material ( fuel lines, o-rings, seals ) that is not made for use with it. Also being alcohol it absorbes water... so it is Ethanol free 92 pump gas or race gas for me.
 
Welcome to the new world. Pump gas in Kali is good for about two weeks in a plastic container. If you don't use it quickly.....well....it's junk and use it for cleaning parts.
 
I have already witnessed the effects of ethanol. When I cleaned the carb it was literally coated with this thick white stuff, I wasn't ever sure what it was. I though it was mice urine or something because inside the air filter and into the carb was the biggest mice nest I've ever seen. My friend said that it's from the ethanol, so I really can see it hurting the engine eventually.
 
This is why I drain any fuel left in tank after use and store in steel jerry cans. I also use an octane booster that is advertised in the VMCC journal, my Greeves Challengers pink on 97 octane
 
You must log in or register to reply here.
Back
Top