icebreaker. The issue is with the fuel/mapping. You now have a detonation sensor that is very finiky to lean running conditions, and is detuning your sled. Get the pc-v from ulmer, and you will get consistent rpms all the time. I assume that you are running premium fuel, but still that is not enough somtimes with lean fuel mapping. Talk to Alan Ulmer, he will set you up 

BlueApexXTX
Extreme
My 2011 XTX ran 117 in 2000 ft on ice, 44 degrees out.111 on snow packed trail,Gps speeds. The speedo was 5 mph at 117.Ulmer airbox pc5 and his clutching.
icebreaker
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Mine doesn't start well when it is hot like after riding hard.yamaha1973 said:never thought about the exup being out of adjustment, maybe try that, ive heard they can start hard if out of adjustment as well...
icebreaker
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Took the sled into the dealer today said the exup exhaust flipper was adjusted right and working fine. dont know what else to check?Mad Russian said:The 2011 apexs speedo is only 2mph off vs 06 -10s r 14mph off. Had an 07 apex, speedo read 124mph but the gps said 109.6 mph. And my 2011 apex speedo 113mph and gps 111.4mph. But yea your exhaust flap could be way off and that would cause that 4 sure!![]()
yamaha1973
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knock sensor kicking in? this was said before, you runnning 91 octain fuel?
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running 91 fuel with a bottle of octane booster, might even try a little race gas mix to make sure the dealer also said there were no codes.yamaha1973 said:knock sensor kicking in? this was said before, you runnning 91 octain fuel?
yamahahaapex
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icebreaker,notsure if you mentioned this somewhere but how many miles on your sled? i had to wait to 1500kms before rpms came way up and after clutching, pcv, airbox im hitting over 100mph in 600 ft and well past 120mph. its one thing slapping mods on but you gotta know how to adjust for your area and test, test, test. these things are bullets and its the first new machine out of 4 that i drove hard right out of the box. fastest sled ive ever owned.
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Ya it probably needs more time to get run in. My previous apexs had way more miles. Guess I will have to plug in the garden hose and put it on a jack stand a let her go for a while.yamahahaapex said:icebreaker,notsure if you mentioned this somewhere but how many miles on your sled? i had to wait to 1500kms before rpms came way up and after clutching, pcv, airbox im hitting over 100mph in 600 ft and well past 120mph. its one thing slapping mods on but you gotta know how to adjust for your area and test, test, test. these things are bullets and its the first new machine out of 4 that i drove hard right out of the box. fastest sled ive ever owned.
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I will never see 120mph on my 2011 xtx ! I run 1.5 in track and im geard down to 23 39. But it flyes 0 to 100 when we got good thick base. 

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Mad Russian said:I will never see 120mph on my 2011 xtx ! I run 1.5 in track and im geard down to 23 39. But it flyes 0 to 100 when we got good thick base.![]()
Bet its a rocket

Mad Russian
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All my testing results were done on thick based trail with loose snow on top. Im sure the mph will improve by at least 5 mph if the tests were done on glare ice. Apexs r prone to loose top speed in trail conditions do to there hevy front end. My buddys apex varyid 11 mph between the 2 conditions ! But i dont even consider glare ice as a true test cuz we ride on thick based snow 90% of the time so there is no need to fool myself on the true results. I tune my sleds for the snow...



Having the same problems it will only run 10000 rpms and 100mph the sled has 350 miles on it but just seems slow on the big end just wondering if there is a breakin chip or a certain amount of hours until it pulls top rpms
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That is what I was wondering to my dealer says no. So I geuss I will have to put some more miles on and see. I was thinking about a power commander and air box mod but don't know who setup is better. Everybody's selling there deal.machzed said:Having the same problems it will only run 10000 rpms and 100mph the sled has 350 miles on it but just seems slow on the big end just wondering if there is a breakin chip or a certain amount of hours until it pulls top rpms
Banks93
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Mine did the same until about 1200miles. Now it is back to the what I expected.
Mad Russian
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The motor is super tight ... It usually takes 1,000mi before it starts to get loose and fast... 

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