Hello all,new to HDT. This is my first post and hope it's in the right place. I have a 02 RK with a stage 1 kit. It has almost 80K miles on it. I have a miss at all speeds. Done the easy stuff, plugs,wires & fuel filter. Using the jump wire at data port to get codes, I get no code. Seems to get worst when it gets to normal operating temp. I have the service manual but I've found out that I probably need the electrical manual. Any info will be appreciated

 

There are so many things that could be the cause...

You have to go through steps to isolate if it is a fuel/air, compression, or electrical problem. Changing parts out gets expensive. Start with a can of wd40, and spray it around the intake manifold where it meets the cylinders. If the engine smooths out, you may have an intake leak.

With the engine running, use something to pull the spark plug wires one at a time, to see which cylinder is missing. Make sure the tool you use to pull the plug wire is well insulated!

If you have compression gauge set, run a compression test. Might also need to do a leak down test. If you don't have the tools, might have a shop run those tests for you. You could have carbon buildup on a valve, or excessively worn valve. Does the engine pop either through the intake or the exhaust? That might indicate a valve is burned/cracked/bent and needs replacing.

Does the engine smoke? If it does smoke, when does the smoke occur? Like does it smoke when you first start it up, then a short while later the smoke isn't as bad? Or, does it smoke all the time? Is the smoke white, or black? Black smoke indicates too much fuel going to the engine. White smoke indicates oil being blown by worn piston rings, or leaking valve stem/seals, or even just a blown/leaking gasket.

Electrical problems usually necessitate the use of a multi-meter. If you don't have one, you will need one if you are going to perform your own maintenance/service.

You say you have the service manual, go through the Trouble Shooting section, to figure out how to narrow it down a bit...

Do you know the history of the engine maintenance? At 80K on the odo, it could be close to time for a top end rebuild.

 

I have the tools you mentioned even a leakdown tester. I got the bike with 3k miles on it and do my own service/repairs. I like your idea about the leakdown. Those tell a person alot about the engine. I'll give that a shot but it seems to be electrical to me. Sevice manual talks about the MAP,CKS & CMS sensors causing misses. Just hate dropin the 60 bucks on the electrical servce manual. I'm hoping that will give me the values I need to test the sensors. I'm not one that likes to throw parts at a problem. Like you said, It can drain the wallet pretty quick.

 

Leakdown done. About 8% differance! Pretty good for 80k, don't ya think. I was pleasently pleased. Have any ideas on the electrical side? I've cheked the wiring pretty thourgh. Still leaning towards one of the sensors. Guess I'm gonna bite the bullit and get the book. Got two HD dealers within less 50 mi. Their just not always cordial.

 

If it is fuel injected try cleaning the IAC port in the top of the intake manifold with throttle body cleaner.

 

You were dead on! Got home and seen your idea and it worked. I took the IAC out, cleaned it and the intake. Took her on a 40 mile ride and ran like it should. Thumbs up!!