Miss/Stumble at 'cruising speed' (rpm related)


2 replies to this topic
  • trevor450f

Posted March 16, 2012 - 11:40 PM

#1

I've recently rebuilt my '03 (new crank, and all bearings). I also added an hour meter.

I finally took it out for a good ride since its been rebuilt, and I'm noticing a miss or stumble at a specific rpm. My best guess is its at 75% throttle. I first noticed it while cruising down the road, but checked it in other gears and it does the same. It has lots of power up to this spot, then stumbles a bit, then lots of power out the top rpms. I have also started running premium fuel in it, I ran just pump gas in it before it blew up (I know, I know).

Where should I start? Is this likely a jetting issue?

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  • grayracer513

Posted March 17, 2012 - 07:20 AM

#2

What's the difference between pump gas and premium? You're not saying that you are cruising down the road at 3/4 throttle, are you?

  • trevor450f

Posted March 17, 2012 - 07:44 AM

#3

Sorry, 'pump gas' was just regular (89 or 87) out of a bulk tank of our own. Premium is 91 or 93 I think.

My best guess is that it is somewhere in the 75% range when I'm on the road. It seems to be missing right when I'm about to up-shift in each gear. Is cruising at 75% not good?





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