| Author | Message | ||
     Rarebird |
I've got a 03 XB9S (bought new this Spring), that I've put about 5k on since March. It had the Race Kit, which I swapped the pipe back to stock in May, because I felt guilty about the noise in my neighborhood when I got home from work at 02a.m. All has been cool for the freeway portion of the commute, but 2 issues have cropped up that the dealer "can't duplicate to fix..." The dealership, Western Reserve, Mentor, OH, has actually been very cool working with me, so I don't want to sound like I'm bashing them... Also, this is the latest in a long line of bikes, so, though I am new to Harley/ Buell twins, I am not new to bikes in general. Anyway, the first issue is: In the first 10 minutes of nearly every ride, regardless of ambient temp., roll up to a stop sign/ light, first gear, clutch in, feet up to briefly "track stand", clutch out, roll in throttle, commit to the turn, and Phttt! One backfire through the airbox, bike stumbles, hesitates, recovers and issue is resolved for remainder of day's ridiing... Scary as heck when traffic is bearing down on you! 2nd thing, possibly related: Smooth road, extended steady 35-45 mph (as in local Law Enforcement following me home from work), 3200 3rd gear, 2500 4th (5th just lugs at that speed. The bike seems to mildly "chug and surge" along. crack the throttle, and all is right again, until back to the necessary cruise speed. Feels almost like an electrical miss (ie plug wire), but does not get worse under load like a bad wire normally would. No noticeable issues at freeway speeds (greater steady throttle opening), making good power, no noticeable chafed wires or fouled plugs. Dealer dyno'd the bike, minor lean spot around 2500 but flat again by 2800... Am I nuts? Is just the nature of big American twins at small throttle openings? Am I just one of those crazy customers that's always imagining something wrong? We just popped the stock ECM back in this morning to see if it makes a difference, but I haven't had more than about 10 minutes taking it home... Thanks for any input you folks might have! -Mike | ||
| Lovematt |
I am going to guess TPS/Timing for the first thing you mentioned. My bike does the second thing you mention under light throttle conditions and it has a Drummer, open Airbox, K&N, and Race ECM...I think the bike just wants to go so you need to have the throttle on or off...anything in between and it surges and hunts a bit. This is on a bike that several mechanics from several shops have ridden on occasion and mentioned runs really really well. I have driven some hot rods that are the same way...either you have the gas on hard or not at all...otherwise it just jumps all over the place...it is the nature of the beast. | ||
| Dagwood |
Check plugs, plug wires, ignition coil, ECM for small cracks or cuts in one of the leads. How long have you noticed the problems? I ran mine for about two weeks with the same symptoms and it got incredibly worse. My bike is at the dealership. I posted a thread in the KV under "troubleshooting...running rough". Some of the suggestions in there might help you. These problems are not the "nature of the beast". Our XBs are not "supposed" to run like this. | ||
| Lovematt |
I agree the bike should not run the way rarebird says...however a really pumped up bike has a tendency to want the gas on hard or not at all in my experience. But under no cases should a bike just cut out complete or flat out miss even if it is for a short instant. I did read closer what rarebird said and it does sound like electrical. I had similar symptoms with a chaffed plug wire but under a load or when the bike was wet (which doesn't happen often). I changed the wires and problem went away the first ride after that. I will say if the cutting in/out is really fast then it is electrical...if it is blubbery and kind of wavers over a few seconds then it is likely fuel or something with airflow. When I had the cutting out under load I did everything Dagwood mentioned...took a good hour just searching and inspecting so that I was sure of what was going on and eliminating some of the variables. It was good to do this as I buttoned up the wiring a little better in the process and protected it better. | ||
| Rarebird |
Thanks for the input from everyone! I just had one of the Service Writers/ Tech take the bike out today, and he actually noticed what I meant! He thought it felt like "ripples" in the road (I had described it as similar to riding on cobblestones when the road was actually smooth)... For reference, the bike is currently back to stock ECM, same driveability issue EXCEPT no more backfiring. The Tech and I, on seperate occasions, have (visually) checked over all leads and wiring, and found no signs of damage. The problem is no worse when wet, and no worse under load (1500rpm, 5th, WOT)- which seems to preclude plug wires, though this may not be so... Have also considered suspension, but road conditions to seem to be irrelelvant, and dragging the brake to load the susp. has no effect. Thought throttle cable slop, but eliminated as much as possible- no change. Still working at it, kind of hoping it will get worse so as to be easier to diagnose- or, at least, less vague to the Tech! -Mike | ||
| Typeone |
My 12 is going in again, this time for erratic idle and surging while cruising which is almost exactly as you describe in bullet 2 above except mine will do it at highway speed too. Really annoying. I've had the TPS reset a ton of times. Yesterday while on the gas hard above 5K the power dropped out for a sec so it's showing the same surge all over the map. It's like something is turning the fuel off/on, off/on. So odd. I pulled the TFI off thinking that was it. (I was already set at 1--1--1--11 to turn it off) Nope, same weird idle and surging while cruising. I've checked all the usual stuff too. Hoping the dealer can figure out whats up, it'll bug me all winter. Speaking of, I posted in the KV but i'll ask here too... anyone every take the ground wire off the TFI to diagnose issues? I read on the Dobeck forum you can do this but the bike would barely run. HUGE surging at idle (fuel pump noise over and over too) and riding. I had to be off/on throttle just to keep it moving in between the big surges of fuel. Weird. I have a question in to Dobeck too. I had had it after that and took the TFI completely off so the dealer doesn't blame the unit for poor running. She's going in tonight. | ||
| Dagwood |
I just got a call from the dealership. It appears that the issue is melted coil and wires. The shop has a coil and one wire in stock, but has to order the other wire and it will likely take days to come in. All this after they replaced the temp sensor, spark plugs, reset TPS, etc. What a waste of time! | ||
| Buellin_ri |
Off to check my coil I have also been having the same type of issues thanks for the info.  | ||
| Kowpow225 |
This is odd you guys mention this cause my car is having the same symptoms...only mine is under a load usually when it occurs. COIL CHECK! | ||
| Buellin_ri |
My coil is OK. Maybe a TPS is the next thing to look at.  |
