| Author | Message | ||
     Paul_regan |
About two weeks ago I went for a 5 mile ride to the parts store. It's been about a month since I'd ridden. No problems. Was in the store maybe 5 minutes. About 1 minute into the ride home, it started skipping and bucking with some muffler "pops" that I'm used to with the drummer on deceleration. Had a tough time keeping it running but was able to keep moving using a lot of throttle and a lot of clutch. Once I got moving at 50 mph it would run OK for 45 seconds or so then buck a few more times. Tach was erratic. During the next 5 minutes it seemed to smooth out. No engine codes or CEL. Next day, similar thing. Short ride, no problems. Stopped for fresh gas, went through the same issues after restarting. It was less severe and resolved more quickly. Two more rides and it still stumbles a bit every minute or so at constant speed, though it seems to accelerate normally. History - 2006 Uly, 25K. Hard wired fan with a resistor between the (+) and (-) leads from the ECM that used to supply the fan. No obvious damage or cracks to the ECM or wires. Seems like it may be electrical - ECM or ground? Theory is once "something" (? wire) gets warm there's a change in the size or geometry. Gonna clean and tighten up the ground but other than that, I'm at a loss, especially with the lack of trouble codes. Any other ideas? | ||
| Steveford |
When the bike is warm wiggle the ECM connectors. | ||
| Paul_regan |
thanks steve. I'll try that. just pulled the battery to get access to the grounding point and the negative post for the battery wasn't all that tight. till, just finished cleaning up all the battery and ground connections. Last time I did this I was pretty generous with the dialectric grease but i was surprised that most the connectors had a copper-ish tinge. didn't look like rust though. | ||
| Kag |
I did the same thing a couple of weeks ago and the contacts looked the same. I lightly sanded the surface areas then put it back together. | ||
| Steveford |
My money is on that stupid seat, especially with the loose battery connections. I ended up taking a piece of wood paneling and cut it the width of the frame, made two notches for the wiring looms to run through down at the bottom and made it a bit taller than the battery connections. It was just the right thickness to wedge behind the battery. End of problem with the loose terminals but it does look like Jed Clampett's bike! Say, this seat feels like I'm sitting on a board... | ||
| Uly_man |
"was surprised that most the connectors had a copper-ish tinge. didn't look like rust though". These are made of copper and tinned on top. If you file/sand them the tinning will wear off but it is nothing the worry about. The battery post terminals can work loose over time/vibs so they should be checked every now and then. The BAS can start to break down causing a miss. Check that by turning it off with ECM-SPY. There is a sub loom that runs over the rear cylinder head and it can rub through the loom cover and wires insulation. It then shorts the wires exposed cores to Earth on the cylinder head cover as the engine expands in height and/or the engine moves around on reving. I had it on my bike and it seems like a common fault. It could be other things but check the wiring first. | ||
| Paul_regan |
Well I didn't get it back together or road test it due to a plumbing leak at the house. Will I need to pull the airbox, filter, etc to really visualize the loom? And I don't have ECM SPY. Don't suppose disconnecting the BAS or pulling the fuse would work, would it? | ||
| Reepicheep |
I strongly suspect it is your cam position sensor. Do you have access to an oscilloscope? http://www.badweatherbikers.com/buell/messages/384 2/712569.html?1362582842 | ||
| Sagehawk |
Just a note that our 1996 xl and flhr cps also contain a base version of bas. Base meaning, you fall over the the ball rolls out of the V and connection breaks killing ignition. Dunc once stated, look at those cps in nosecone on higher mileage scoots, and if epoxy looks like its melting, then it is dying and needs replacing before it totally quits. Within a year of this conversation, the flhr cps was replaced. Dunc was a prophetic ol coot. |
