I've been chasing an intermittent engine hesitation for a few months now and it's getting very frustration. I don't want to blindly throw parts/money at it so I am interested in some opinion/feedback. I will not throw out or discount anyones suggestion or thoughts.

Basically, my problem feels like the engine is being starved of fuel or is missing spark intermittently (mostly at about 15-20% throttle in low-load conditions). It started showing up only when hot. Now it is becoming more frequent. There are no trouble codes. The dealer is unable to duplicate the problem.

What the dealer checked:
Compression
Plugs
Intake Leaks
Fuel Pressure

What's been replaced by me:
Plugs and Plug wires
Fuel Lines (both) including check-valve
Fuel Filter, Fuel Pump Assy
Throttle Position Sensor

I know there are plenty of things is could be, but I'm pretty much done replacing parts for now until hopefully it breaks hard.

Engine Specs:
103" w/211 Cams
SE Pro Super Tuner
Big Sucker Open Air Intake

I look forward to some good conversation.

Thanks!

 

plugs and wires OEM style? I have read that other plugs may cause the ECM to falsely register spark knock.
resistance of wires is also important.

what exhaust system?

mike

 

Screamin Eagle plugs and wires
Rinehart True Duals

 

Steve, if the local dealer can't find it, you might try and run down to Doc's and have him take a crack at it. Which location did you take it to?

 

Throwing it out there.
Drive belt tension ok?

I heard it feels like a hesitation..
For what it's worth.
Tim

 

Took it to Adamec on Baymeadows. Gonna give 'em another crack at it since it's happening more frequently now.

Where's Doc's?

Tim, Drive belt ok...thanks!

 

Engine temp sensor. I had one that acted up when hot. Bike would hesitate when trying to take off from a stop. Cold it ran fine.

 

You'd be surprised at how loose or corroded battery connections can cause all kinds of issues. Especially seeing as how under low voltage the ignition can fail and falter. Even a battery thats not holding a full charge can cause a bike to run bad and even not to start, even if it's turning over the motor.

It looks to me like your list of concerns is missing both voltage and connection checks but alos a look deeper into the entire ignition system.

Could even be a damaged wire that when warm allows the insulation to stretch enough to break the circuit, or make it intermittant.

Start with battery connections.

 

That's a good call JohnnyC. I have had it happen. Check all your grounds too.

 

I figured it was Baymeadows. They are better than the Orange Park location. Doc's is a bit of a hike, just outside Orlando, but he's really good.
Just out of curiosity, how old is your battery? It could be getting flakey if it's the original.