| Author | Message | ||
     Vortec57 |
Suddenly this spring my 03 XB9R has decided to cut out when warm. Its got a d&d pipe, Buell race filter and race ECM. First time it was doing this I was low on fuel, filled up and it got better, now it's done it a couple times when full of gas. It runs fine above idle and at highway speeds, when slowing down and or at idle it cuts and pops, if it dies its HARD to crank enough to get it back running. Any suggestions as to where to start looking? It's never given me fits before and this seems to be pretty sudden. Typically i'd say it sounds like coil or maybe voltage regulator? | ||
| Ourdee |
How old is the battery? | ||
| Vortec57 |
A couple years on the battery. Its on a tender always. | ||
| Ulynut |
Not sure what you mean by hard to crank, but, check the voltage on the battery with a multimeter. With the engine running you should have 14 volts at the terminals. If that checks out, take the battery to a shop and have it load tested. Shouldn't cost you anything, a few bucks at most. Also could be vapor lock. Check the fuel tank vent tube for obstructions or a kink. | ||
| Glitch |
Next time you go out try to get it to cut out, when it does, open the gas tank and see if it'll start right up. If it does your vent hose is pinched or plugged. | ||
| Wjcunning |
Might be a grounding problem. I had a similar problem last week. My ground post felt tight, but was loose enough to cause periodic electric failure. There is a thread that suggests installing a #10 copper wire directly from the ground post on the battery to the coil housing under the breather cover. The ground plane on XBs appears to be a daisy chain...easy to lose current flow. | ||
| Vortec57 |
By hard to start, I mean if it dies you'll be cranking the starter 30 seconds or more to get it to fire, not hitting the starter and it running. Really don't think its the battery, as it starts cold right off, no matter if im home and just off the battery tender, or if its been sitting somewhere all day. i have no hose on my tank vent, put a dirtbike style valve on it a while back, but ill stil give that a try. | ||
| Greg_e |
Could be a bad coil where there is a contact inside that opens up when hot. Another possibility is a bad relay that doesn't like to work when hot. | ||
| Ulynut |
Wouldn't a bad coil throw a trouble code though?  | ||
| Brumbear |
if it's an 03 it may just be time for a fuel pump give it a shot of the ol seafoam perhaps the screen is dirty inside. | ||
| Trojan |
could be a dodgy rear cylinder temperature sensor (located in the middle of the cylinder head). When these go they throw up soem strange symptoms and don't always show up on a scanalyser  | ||
| Kds1 |
Matt is correct ...first place to look rear cyl temp sensor...been there done that..always keep a spare... | ||
| Xoptimizedrsx |
What Kds1 said. I changed one on mine and put a heat wrap on the lead on the other bike. no more issues. Coil has to be very faulty before its getting codes. not dead but almost. I use a heat gun to get the coil hot and see if it replicates the issue. Then next I heat the fuel pump area and test. Last, I actually apply heat to the ecm to test it. It must work the same hot or cold. Distant heat so not to fry it. normally 3 to 5 mins gets it quite warm above operating temp. A heat gun seems to be a nice tool for intermittent searches only happening after a while of riding. | ||
| Vortec57 |
Thanks for a few more ideas. I'll keep hunting.... just as soon as it stops raining all the time around here |
