I'm opening a new thread on this because there are so many threads re: the Guhl reflash that I'm worried it'll get buried in the noise.
I just got my ECU back yesterday. They did the standard FZ8 deal, which they will explain, but in brief it just opens the engine up and removes a number of factory restrictions while increasing redline. One adjustment they made for me is to account for the new K&N air filter, other than that, my bike is stone stock; exhaust and slip-on are all standard, stock items.
Well, you never know with electronics. I was just happy when the bike started after I put it all back together. First ride was about 30 miles of freeway at night. Yep, it felt quite a bit faster but freeway at night is hardly the place to be opening up your machine. I stuck to the basic speed law but it felt promising.
Today we had good weather, perfect in fact. I did 175 miles, of mostly very twisty to moderately twisty roads that I've been riding for well over 25 years.
I have to also mention that I put on a brand-new set of Dunlop Q3's, and that I have an Ohlins rear shock, along with having changed the fork oil out for 10wt (stock is 5wt).
I probably did around 80 miles of just twisted pavement, back and forth, up, down, over, and around. After an hour or more of this the darn thing was feeling so good, I was U-turning to follow the odd sportbike rider up or down the hill. By this time the Q3's were broken in, which was a good thing.
Bottom line here, this bike is stupid fast now. It is ridiculous. I cannot use all the power. It's easy to lift the front wheel in the first two gears for sure, and I suppose one could even pull it up in third. I'm not about wheelies, but the way the power comes on in every gear, everywhere, is greatly increased. From the seat-of-the-pants, it feels as strong as a Generation One FZ1. I had one of those for five years. That bike makes about 120 HP at the rear wheel and 70 lbs feet of torque, but it's weighing in at about 510 pounds compared to 467 lbs for the FZ8. That's over 40 pounds of pork there. Also, the older FZ1 engine was rather slow revving. So with the lighter weight and much quicker-revving engine, to my mind, the FZ8 with the Guhls reflash and K&N is a real close match to that 2005 FZ1.
The acceleration increase is almost mind-numbing compared to the stock bike. I also own a 2012 GSX-R 750 and for sure, the FZ8 with the reflash will smoke it anywhere below 10K RPM. After that, the Gixxer is just gone, but down low it has more torque and HP and more important, more driveability.
Everyone knows the FZ8 has a "flat spot" around 5500 rpm. It's not a dead spot, the power just flattens out and then starts to build again above 6K, and when it hits 7K it starts to pull pretty hard. With the reflash, it pulls REAL hard from 7K to 12K, plenty darn fast enough to get you into your favorite corners a lot faster than you are used to. This happened to me several times today. I was like, "WTF? Good thing this bike has good brakes, WHOA!"
This bike has two modes, so to speak; from 2K to 5.5K, it's real torquey and pulls clean and strong. She feels neutral as you pull through 5.5, and when you hit 7K, watch the hell out, because that tach needle will swing up to 12K in less than a second, if you are in 1st or 2nd gear. In the past I didn't spend much time above 9 grand because the bike was pretty lazy getting past that. It would do it but without any real excitement. Now it just plain "zings" right up there. Below 5500, it feels like a strong 900, plenty of torque and very rideable around town.
Anyone who's used the Q3 knows that they are just about the best and stickiest tire going for track days and hard sport riding. I'm out to maybe 3/8" chicken strip on the rear now, and I can tell you this thing gets out of a corner FAST. Towards the end of my ride, I did in fact feel the rear start to push a little, on clean dry pavement in a turn I had been over several times before. Now given the stick of the Q3's (at least as good as the Supercorsas on my Gixxer) that is saying something.
The engine braking is reduced noticeably, they got it exactly where I wanted it. Throttle pickup is noticeably smoother. This bike has a lot of mechanical driveline lash so I don't think this will ever be as smooth as the best bikes out there (the GSX-R 750 being one of these, it's nearly perfect) but it's very good, and a good rider can flat steam along on this reflashed FZ8. You will be using the brakes more, first because of the much harder acceleration, and secondly because of the reduced engine braking (this can be tuned so just tell them how you want it).
Bottom line, it's a whole different ball game for the FZ8 when you do the reflash and K&N, and mount premium sporting rubber. This bike may not be quite as fast as an FZ-09 in a straight line, but I will guarantee you it's not far off, and without all the problems. Fortunately Yamaha gave us a very rigid, tuneable, stable chassis with the FZ8, and with just the Ohlins and fork oil change this bike is very rideable on all kinds of pavement, especially with the Q3's. I'm planning on doing the Racetech Gold Valves and springs for my weight, but that's a ways down the road. At that point I say that the FZ8 will hold its own, or best, any danged naked bike out there in a real-world situation.
Guhl is not doing me any special deals or favors, I paid full pop, but I will say this as it needs to be said: this seriously unleashes the real power in the FZ8's engine, and I don't recommend it for new riders under any circumstances. Like I said, I was getting the Q3 to push in the rear under hard acceleration on clean pavement.
ADVISORY
If you are a new rider, and you don't want to quickly learn about what a highside is, don't have this flash done. Give yourself a few thousand miles to get used to the bike.
If you are an experienced rider and you want the ultimate FZ8, one that can hold its head high among the field of nakeds out there, consider doing this flash. But take some time getting used to the extra power.
Remember, motorcycling is a darn dangerous sport. Gear up and know your limits.
I just got my ECU back yesterday. They did the standard FZ8 deal, which they will explain, but in brief it just opens the engine up and removes a number of factory restrictions while increasing redline. One adjustment they made for me is to account for the new K&N air filter, other than that, my bike is stone stock; exhaust and slip-on are all standard, stock items.
Well, you never know with electronics. I was just happy when the bike started after I put it all back together. First ride was about 30 miles of freeway at night. Yep, it felt quite a bit faster but freeway at night is hardly the place to be opening up your machine. I stuck to the basic speed law but it felt promising.
Today we had good weather, perfect in fact. I did 175 miles, of mostly very twisty to moderately twisty roads that I've been riding for well over 25 years.
I have to also mention that I put on a brand-new set of Dunlop Q3's, and that I have an Ohlins rear shock, along with having changed the fork oil out for 10wt (stock is 5wt).
I probably did around 80 miles of just twisted pavement, back and forth, up, down, over, and around. After an hour or more of this the darn thing was feeling so good, I was U-turning to follow the odd sportbike rider up or down the hill. By this time the Q3's were broken in, which was a good thing.
Bottom line here, this bike is stupid fast now. It is ridiculous. I cannot use all the power. It's easy to lift the front wheel in the first two gears for sure, and I suppose one could even pull it up in third. I'm not about wheelies, but the way the power comes on in every gear, everywhere, is greatly increased. From the seat-of-the-pants, it feels as strong as a Generation One FZ1. I had one of those for five years. That bike makes about 120 HP at the rear wheel and 70 lbs feet of torque, but it's weighing in at about 510 pounds compared to 467 lbs for the FZ8. That's over 40 pounds of pork there. Also, the older FZ1 engine was rather slow revving. So with the lighter weight and much quicker-revving engine, to my mind, the FZ8 with the Guhls reflash and K&N is a real close match to that 2005 FZ1.
The acceleration increase is almost mind-numbing compared to the stock bike. I also own a 2012 GSX-R 750 and for sure, the FZ8 with the reflash will smoke it anywhere below 10K RPM. After that, the Gixxer is just gone, but down low it has more torque and HP and more important, more driveability.
Everyone knows the FZ8 has a "flat spot" around 5500 rpm. It's not a dead spot, the power just flattens out and then starts to build again above 6K, and when it hits 7K it starts to pull pretty hard. With the reflash, it pulls REAL hard from 7K to 12K, plenty darn fast enough to get you into your favorite corners a lot faster than you are used to. This happened to me several times today. I was like, "WTF? Good thing this bike has good brakes, WHOA!"
This bike has two modes, so to speak; from 2K to 5.5K, it's real torquey and pulls clean and strong. She feels neutral as you pull through 5.5, and when you hit 7K, watch the hell out, because that tach needle will swing up to 12K in less than a second, if you are in 1st or 2nd gear. In the past I didn't spend much time above 9 grand because the bike was pretty lazy getting past that. It would do it but without any real excitement. Now it just plain "zings" right up there. Below 5500, it feels like a strong 900, plenty of torque and very rideable around town.
Anyone who's used the Q3 knows that they are just about the best and stickiest tire going for track days and hard sport riding. I'm out to maybe 3/8" chicken strip on the rear now, and I can tell you this thing gets out of a corner FAST. Towards the end of my ride, I did in fact feel the rear start to push a little, on clean dry pavement in a turn I had been over several times before. Now given the stick of the Q3's (at least as good as the Supercorsas on my Gixxer) that is saying something.
The engine braking is reduced noticeably, they got it exactly where I wanted it. Throttle pickup is noticeably smoother. This bike has a lot of mechanical driveline lash so I don't think this will ever be as smooth as the best bikes out there (the GSX-R 750 being one of these, it's nearly perfect) but it's very good, and a good rider can flat steam along on this reflashed FZ8. You will be using the brakes more, first because of the much harder acceleration, and secondly because of the reduced engine braking (this can be tuned so just tell them how you want it).
Bottom line, it's a whole different ball game for the FZ8 when you do the reflash and K&N, and mount premium sporting rubber. This bike may not be quite as fast as an FZ-09 in a straight line, but I will guarantee you it's not far off, and without all the problems. Fortunately Yamaha gave us a very rigid, tuneable, stable chassis with the FZ8, and with just the Ohlins and fork oil change this bike is very rideable on all kinds of pavement, especially with the Q3's. I'm planning on doing the Racetech Gold Valves and springs for my weight, but that's a ways down the road. At that point I say that the FZ8 will hold its own, or best, any danged naked bike out there in a real-world situation.
Guhl is not doing me any special deals or favors, I paid full pop, but I will say this as it needs to be said: this seriously unleashes the real power in the FZ8's engine, and I don't recommend it for new riders under any circumstances. Like I said, I was getting the Q3 to push in the rear under hard acceleration on clean pavement.
ADVISORY
If you are a new rider, and you don't want to quickly learn about what a highside is, don't have this flash done. Give yourself a few thousand miles to get used to the bike.
If you are an experienced rider and you want the ultimate FZ8, one that can hold its head high among the field of nakeds out there, consider doing this flash. But take some time getting used to the extra power.
Remember, motorcycling is a darn dangerous sport. Gear up and know your limits.
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