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Discussion Starter · #1 ·
I'm experiencing a hesitation during the first 4 or 5 minutes from a cold start. Once the engine has warmed it goes away and seems to run fine. Anyone else experiencing this?
 

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Discussion Starter · #3 ·
Yes, a good warming up fixes it.
Are you saying you have the same experience?. I'm trying to determine if this is normal. I have a graves flash and exhaust and thought I may need to run the y to the dealer before I install the flash. But if this is normal it will save me the time of going to the dealer and having them tell me it's normal.
 

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Same with mine. Normal. Warm it up, and it's fine. Minor annoyance.
 
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Discussion Starter · #6 ·
Thanks everyone. Seems this is just a idiosyncrasy with the machine.
 

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Its lean bud. They come lean out of the box, particularly in the first 1/4 throttle. Did you have a cooling in AZ? that might have temporarily affected things but honestly, thing is super lean on the bottom. My advice to anybody would be to get a fuel controller and play with it on richening the sequence of injection. I'm not real good at it but I can make a difference. Guys dropping the baffle will notice this requirement immediately.
 

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Might be with the smog emissions they had to run a leaner mapping until the catalytic converter warms up then they can switch to a richer air fuel ratio mapping and they are also using a purge air system to help lower tailpipe emissions on the yxz.
 

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Yup lean right off idle or when you stab it you will experience the hesitation. I was hoping a programmer or flash would clean this up. It's a minor annoyance.

Most new FI off road bikes and ATV's experience this. My KTM 500 was so lean off the bottom it would flame out and stall!!

It's a emissions and EPA thing.
 

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Yup lean right off idle or when you stab it you will experience the hesitation. I was hoping a programmer or flash would clean this up. It's a minor annoyance.

Most new FI off road bikes and ATV's experience this. My KTM 500 was so lean off the bottom it would flame out and stall!!

It's a emissions and EPA thing.
spot on. Makes ya feel like a rookie, stalling it in corner cuz there's no fuel.
 

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I'm experiencing a hesitation during the first 4 or 5 minutes from a cold start. Once the engine has warmed it goes away and seems to run fine. Anyone else experiencing this?
I have had the same issue from the day I took it home.. Let it warm up a couple minutes and she is Happy Happy I did notice that once I took the baffle out it took a bit longer to get rid of the stumble.. Just a lean machine..
 

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Discussion Starter · #12 ·
Just put a graves exhaust on and flashed the ecu. Still a little hesitation but runs strong and sounds freaking awesome.
 

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Just put a graves exhaust on and flashed the ecu. Still a little hesitation but runs strong and sounds freaking awesome.
I'm curious to hear about the overall performance gain you're going to see from that combination.
 

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Discussion Starter · #16 ·
I'm curious to hear about the overall performance gain you're going to see from that combination.
Took it out for a short blast and seems strong. The sound is music. I'll know more this weekend.
 

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Discussion Starter · #19 ·
You won't need one with a 10hp gain I think is what they posted on the dyno. It also shaves off quite a bit of weight!
The stock muffler is real heavy. So yes shaves a bunch of weight
 
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