Snomad
Extreme
I wanted to see if someone at a dealer could clarify how this system works. I had the impression from way back (maybe the brochure) as well as this forum that the system would sense knock and adjust the timing at the expense of horsepower. Reading the manual however, it appears that the knock sensor light comes on but you are then supposed to reduce speed, etc. and use only premium. Sounds to me like the system is not adjusting for fuel but letting you know to reduce load on the motor and replace or add premium to low octane or poor fuel. What is the truth of this. I think we may be assuming that the system adjusts because there are other systems out there that do. The manual certainly does not give the impression that this sytem adjusts timing. If this is the case I will definitely get some octane booster to add should I not be able to get premium fuel. You don't want to have to ride at reduced speeds untill you burn up half or more of a tank of gas. Additionally, I thought that the info I saw before I spring ordered said the minimum recommended fuel was 91 octane (mid-grade). Am I wrong on this? Let's hear from someone who knows for certain. Thanks.
GypsyRoots
Expert
This is interesting...I do not know for sure either, but would like to hear a knowledgeable answer as well...
scb
Newbie
There was an article in American Snowmobiler or Snow Tech that described how the sytem worked. It said that it adjusts the timing only when you are past quarter throttle and above a certain rpm. I can't remember all of the details. I'll have to go and see if it is still on the shelf and get it.
cdnredline
Veteran
We were told from the beginning that the new engine would have what amounted to three different running modes dependent on knock. Full power would be with good (premium) fuel, a reduced power level of but no light with regular fuel and a warning light/reduced operating rpm "limp mode" with poor fuel.
From our real world experience I can verify that at least the top two levels do exist (haven't see a crap fuel limp mode yet). Most of the riders are just using regular and they think they run fine. When they try premium from a busy station or one they know is fresh (or octane boost) the mid-range is noticably stonger as is top end somewhat. Yamaha had told us to expect a 3 to 4 horsepower reduction on regular fuel so the addition of premium can be the easiest 5% increase you can get.
From our real world experience I can verify that at least the top two levels do exist (haven't see a crap fuel limp mode yet). Most of the riders are just using regular and they think they run fine. When they try premium from a busy station or one they know is fresh (or octane boost) the mid-range is noticably stonger as is top end somewhat. Yamaha had told us to expect a 3 to 4 horsepower reduction on regular fuel so the addition of premium can be the easiest 5% increase you can get.
Bakemono
TY 4 Stroke Guru
By tell you to slow down and reduce the load on the motor when the light comes on, Yamaha is probably trying to lessen the chance of engine damage. If that engine fails, you are looking at at at lot of money to rebuild it. I know that it costs anywhere from $1,500-$3,000 to rebuild a 250F dirtbike motor (which is the engine the Genesis 80 FI is based on), so you can only imagine how much it would cost to rebuild a Genesis 80FI if it blows up. Yamaha is probably concerned about how much they might be paying out in warranty claims, and is just playing it safe.
Snow Goer had a tech article about the Genesis 80FI in a recent issue and they stated that you could run 87 octane fuel if aboslutely neccesary, but they kinda hinted that you should always try to run 93.
Snow Goer had a tech article about the Genesis 80FI in a recent issue and they stated that you could run 87 octane fuel if aboslutely neccesary, but they kinda hinted that you should always try to run 93.
rupprider
Expert
Saturday, the 30th, I looked at a Phazer GT in the a dealer's showroom, and it had a sticker just above the gas tank fill that called for 91 octane. Or did I misread it? RR Edit: This was in Ohio.
Snomad
Extreme
I was finally back at my dealership today and asked about this issue. As I mentioned previously the manual says nothing about what the machine will do with poor fuel. Anyway, I am told by the dealer that the timing will be adjusted by the machine to accommodate low octane fuel. An expected 4 horse loss with regular. With very poor fuel you are more likely to see the knock sensor light and will likely have to reduce speed, etc.
BV1
Expert
91 Octane is recommended here in Canada.
I would use 93 if you can get it, but 93 is more of an American gas
Very hard to find 93 here, usually have to drive out of the way to get it. I only know of two gas stations in Winnipeg that sell 93-94 and its a 10% ethanol blend.
-Steve
I would use 93 if you can get it, but 93 is more of an American gas
Very hard to find 93 here, usually have to drive out of the way to get it. I only know of two gas stations in Winnipeg that sell 93-94 and its a 10% ethanol blend.
-Steve
snocat7
Newbie
I drove the new Phazer GT to break it in last weekend for the first time. It was warm out and the snow cover was low in spots. The yellow light on the bottom left of the speed came on several times. Per the owners manuel you are to stop and let it cool down when this happens. I hope they come out with a rear hear exchanger. Where is the detonation light? And what color?
Similar threads
