I have an '05 Heritage Classic with a stock EFI motor (Stage 1, only). It only has about 1000 miles on it.

It will cut out when the bike is at a steady low rpm speed (around 30-35 mph in 3rd gear). It will just cut out for what just seems like one stroke. Never missed under decel or acceleration. Seems to happen when it is good and warmed up. No backfire or sputter, just a miss?!

The bike has already been in to the dealer for the problem, but it is very hard to get it to do it and they could finf nothing wrong. I realize the rpm's are low, but the engine is not so low that it lugs.

Anyone have a similar problem?

 

Wow that sucks. How often does it happen?

Ryan

 

That's the problem - It is very irregular and has to be at a very steady low rpm speed. Wish I had a tach to know exactly what the rpm is.

I know little about these motors, but if it was a car I would think about a bad plug or low spark - dealer was suppose to have check these. Seem to be on the spark side, not fuel. It does not sputter. Almost like you'd hit a kill switch for a fraction of a second.

Other than that - it is a great ride - it taken the place of the Z06 as the preferred mode of transportation!!!

 

Out of curiousity, does it do it only under load? Can you check it while in neutral and running at about the same RPM? My slightly older Sloptail used to do it, almost like it was losing spark for just a beat or two. Cured it by richening the mixture a wee bit at the time I modified my drag pipes.

 

It seems like it requirs a load...spent about 15 minutes with the thumb screw in at a bit above idle, but no cutting out at all...

 

Has the bike registered any codes yet?

One other thing, check the battery post connections, sometimes they can be a little loose and cause the fuel pump to shut off for just a moment under vibration or road bumps. I had that problem once, it would only do it everynow and then, like to have drove me crazy until we checked the battery connections. Just a thought.

 

According to the dealer, no codes yet. I did a once over on all the connections - but I'll disconnect and reconnect the battery, just in case.

It does not seem to be related to a bump in the road.

Smooth, level constant low rpm speed....and then....pause...continue running. Maybe it'll do it again, maybe not. Very annoying! Does seem to have to be good and hot, not just a 5 minute warm-up. That may be just coincidental, though.

 

If no codes then, it may just be what I call a stumble at low rpm's sometimes my bike will do that. Just keep riding it and if it's something else it will show up on a code maybe. Try to run that speed in second gear and see if it does it, you may be lugging some at at that speed in third gear.

 

i know what your going through it feels like it looses spark on one cylinder for a split second, mine does it too. except mine does it from 2500 and below, it bucks and jerks. if i give it juse a little throttle it straightends out for a little while, then it starts all over again. on the highway 2500 and over.....it runs like a raped ape, and extremely smooth. no lights no codes.

 

I drove a '00 Merc. Mountaineer for 3 years asking the dealer why it had a strange miss at low RPM under a slight load. Turned out to be 1 bad plug wire shorting out - NO CODES!!. Sounds electrical.....for my own peace of mind, doesn't cost much, replace the 2 wires and plugs. Don't buy the fancy plugs, just regular HD. You just never know and for $25 ? you might find it.