I believe I am having a bit of a fuel mapping issue with my Nytro. One day she will be running great, and the next she is sounding like she wants to go, but just can't. It is making the clutch difficult to set due to the performance variables from one day to the next. Twice I have had it up at Hauk, and after adjusting the clutch on the lake with him she ran awesome. Just the way I wanted it. Quick off the line, and 108 on the gps. This way I had some top end, and a lot of corner to corner. Those days it was about -10F outside. Then a weekend later when I go and take her out when it is 18-30f she has a mind of her own. The first day on our last trip she had no back shift, and absolutley no top end. I raced a new 4-tec 1200, and took it out of the hole, but at around 60mph he just passed me up 
. With all of these mod changes something had, and has to be off. First thing is theextra power mine has, and the other that was a poo. So we took out one nut off the center of the primary to raise the rpm's. This got it to around 8700-8850. Performed a little better, but no mid range. The next day we went out, and left it the same not to slow down everyone elses trip, and she ran great!. 8800-8950 rpms 5200 at 50mph, and instantley back up when you hit her. I think we need to take a bit more weight out to get her to 8950-9000rpm's. The other thing is that the spring was changed by Pat to a much stiffer spring, and new Helix. He said to leave the secondary alone, and tinker with the weight for now. That still doesn't explain the differnce in performance from day to day. I am thinking of throwing an exhaust/o2 gauge sensor on this to see how, and when she is changing. That way I can check and tinker with the mapping controls on the programmer. Any ideas? The clutching wouldn't change this drastically from day to day with simialr conditions. That is what is making us think it might be running to rich or something? Turk you are always welcome on this one 
Any suggestions guys? Any ideas on what type, and brand of sensor worked best for you guys in the past? Thanks for the help again
. With all of these mod changes something had, and has to be off. First thing is theextra power mine has, and the other that was a poo. So we took out one nut off the center of the primary to raise the rpm's. This got it to around 8700-8850. Performed a little better, but no mid range. The next day we went out, and left it the same not to slow down everyone elses trip, and she ran great!. 8800-8950 rpms 5200 at 50mph, and instantley back up when you hit her. I think we need to take a bit more weight out to get her to 8950-9000rpm's. The other thing is that the spring was changed by Pat to a much stiffer spring, and new Helix. He said to leave the secondary alone, and tinker with the weight for now. That still doesn't explain the differnce in performance from day to day. I am thinking of throwing an exhaust/o2 gauge sensor on this to see how, and when she is changing. That way I can check and tinker with the mapping controls on the programmer. Any ideas? The clutching wouldn't change this drastically from day to day with simialr conditions. That is what is making us think it might be running to rich or something? Turk you are always welcome on this one Any suggestions guys? Any ideas on what type, and brand of sensor worked best for you guys in the past? Thanks for the help again
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- 2014 Yamaha SR Viper LTX, 2014 Yamaha SR Viper RTX SE, 2015 Yamaha SR Viper MTX SE 162 (turbo), 2015 Yamaha SR Viper MTX SE 153
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You have the Power Commander installed for running the fuel, correct? If you want a wideband I would look at the Wideband Commander model 15-7013 from Dynojet. Then buy an LCD screen and you could datalog engine rpm, throttle position, and air/fuel ratio without any problems. This would allow you to replay it right on the LCD screen or you could also download it to a laptop. It will also hold multiple different maps for testing as well. The whole setup would run you around $600-650, but for what you've got invested in that thing it would be the ultimate setup to tell you EXACTLY where your Air/Fuel ratio is at on certain RPM & throttle positions.
Srxspec said:
Yes I have the power commander, and the ignition controller also. Once I get that correct/close I might be up for clutch change, IF the one I have doesn't want to participate in the fun I want to have
. Heard your clutch has a nice mix compared to the Drag n Fly, and some of the heel clickers? It supposidly doesn't effect top end while raising initial torque, and giving decent back shift? Two other suppliers I talked to said that Drag n Fly, get you there fast, but sacrifices other areas to get you there. What is your opinion? I run mostly hard corner to corner riding, and wide open on the straights, and lakes. Thanks again
Hey Turk, what do you think? Same thing? Since you are one of the tech Guru's on this site
Your sled should pull the same rpm,s(with in 1-200) every single day . I have K & N,s with fuel controller & my rpm,s are the exact same every time I ride it. You have an issue that is either fuel or timing related....or.....try the easiest thing 1st & change plugs. seen that happen more then once!!
Turk said:
I will try a new set of plugs first. If that don't work, then go to the mapping problem. Thanks for pointing out the obvious. A lot of on/off riding on the lake testing and tuning the clutching, then shutting her down to trail ride the next week could have caused an issue. Don't hurt to try this option first. Thanks, again
Srxspec said:
Allen,
It was nice talking to you yesterday. I appreciate the great help, and customer service, with my programmer issues. Tell you how it goes once I get into it. thanks
