| Author | Message | ||
     Björn |
I know this is not the correct forum for posting technical questions but the I didn't find a category suitable for it, don't know if it's an electrical or mechanical problem yet. Hope I can get away with posting the question here  I work for a dealer in Sweden and we have a XB9r, one of the first ones in Sweden so it's an early edition, that have been running poorly since the beginning. The idle is very rough and it runs erradically(spelling?) but ones the revs go up it runs OK. I know that it's nearly impossible too answer what it could be, but I've seen that there is an enormous knowledge bank here and I was hoping that somebody would've possibly gone thru the same thing and could give some pointers. I haven't worked on it myself, but the fuelpressure and tps and compression have been checked so far. The tip from Buell is to replace the whole throttle housing wich is the next step. But I just wanted to check with you guys if you've got some inside info before it gets torn to pieces!  I know it's not likely that solution is an easy one, but it's woth a try!!  /Björn | ||
| Gentleman_jon |
Almost impossible to guess at this distance, but a lot of demo Buells have had their spark plugs fouled by starting the motor in the show room, giving it a few blips, and then turning it off before it warms up and leans out. You might want to change the plugs. A bit easier than changing the throttle body, but not much:-). The Denso Iridiums are a good plug to replace the originals. US part number is: IX U24 just my .02¢ | ||
| Odie |
May be intake seals. See the Power Commander thread on this board for a little more info...... | ||
| Björn |
Hello Jon and thank you for your reply! The bike has run poorly since the first start up and the plugs have been checked. It sort of runs like it would be the plugs that are foul, but all of the regular stuff has been checked. And I fully realise that this one probably won't be solved here, but if there is somewhere somebody would have run in to the same problem it's here! Also the ECM has been temporarily replaced with others without any difference in behaviour. And it's just been ridden it's first ten miles were it was astablished that it runs OK in the upper rpms.Cam timing and induction leaks has also been tested. So this is just a last resort of finding the fault easily. But it seems like we're gonna have to get are hands dirty on this one  I just wanted to check with you guys before we start ordering parts just to find out that there's nothing wrong with that part. We don't have a so much XB9 stuff on the shelves. The XB12 is waaay more populare here! | ||
| Chainsaw |
Have you reset the TPS? | ||
| Henrik |
Like Chainsaw said; seems like a throrough TPS reset, maybe followed by careful idle adjustment (I believe the bike should be hot when adjusting) has often cleared up rough running as you describe. Please let us know what you find out. Could help out someone else down the road. Henrik | ||
| Björn |
Yep the TPS have been reset (more than ones). The ignition timing has also been checked. Camcover has been off to check camtiming, so we've gone through all the regular stuff. The compression differs between the cylinders however it is withtin the limits. Don't remember the exact numbers but I do remember it was within the limits and nothing out of the ordinary. We have of course been in contact with Buell and they've told us just too replace the throttlebody. We have inspected the throttlebody and can't find anything obviuosly wrong with it but that doesn't meen that it's ok. As I said, it would be fun to here if any of you guys have experienced anything similar! I've seen dealership people posting here so maybe one of you guys no what's going on. But of course this could be a first as well! As with all troubleshooting it's not a problem replacing the broken part, it's the problem of finding it! And since we don't have an xb9 throttlebody laying around an easy switch isn't awailable. And it would be a bummer getting a new throttlebody and it still wouldn't work! I appreciate your posts! Kepp 'em coming   | ||
| Sammigs |
Have you checked to make sure the injector leads are on the correct injectors? Have you checked the injector spray patterns yet? Possibly a clogged injector or injectors. What color are the spark plugs? (black,brown,white,tan) What condition is the fuel in? (smell it) | ||
| Björn |
Hey there Sammigs! The leads have been checked. Fuel is A OK. The thing is that it runs like the spray pattern would be wrong and fouling the rear plug. But the plug stays clean. And that sounds like the injector would be completely clogged up but it runs good higher up in the rpms. With H-D (wich we work with the most) when the injector gets clogged it, most of the time, fouls the plug. The injector never gets completely clogged. And if it would get completely clogged it most likely wouldn't run as good as it does in the higher rpm. But never say never That's the thing we're going too be checking next, the injectors. But we've gotten some inside tech-tips from Buells tech department. Don't remember exactly what it was but it was some thing about the butterfly shaft in the throttlebody. It had been some problem with it in a small number of bikes. So if somebody has hade that problem it would be interesting too hear about! And the reason why I don't remember all of the facts is because I'm not working with the bike myself. My workmate is going too start working with it again soon and I just wanna show off and tell him what the problem is before he starts  | ||
| M1combat |
Are you backing the throttle plate down to closed when you reset the TPS or leaving it alone (set where it'll idle)? Any engine lights? Just how low of RPM's are we talking about? | ||
| Björn |
The throttle plate is close as per manual. But we've tried fiddling with it too. And that's not the problem unfortunately. No fault codes. Don't know exactly which rpms, but it's from idle (1050-1100) and a bit above. Don't know when it starts too run good other then "higher up" in the rpms. | ||
| M1combat |
Well... It won't run really well under about 2K. You should be able to cruise steady throttle at 1700 or so but once you add throttle it'll start to "lug" under about 2200 on a nine or about 1800 on a 12. I generally cruise around about 2300 on my twelve. Do you have other bikes to compare it's characteristics to? | ||
| Björn |
Yeah I know what you mean. I'm a Harley/Buell mechanic so I can easily compare it with others and it doesn't run good! It runs really bad on idle and stand still. Just like a foul plug our as previuosly mentioned clogged injector. | ||
| Kds1 |
Hey Bjorn,( I don't know how to put those 2 dots over the o ), just something that I remembered in the past, check the bank angle sensor just to make sure, sometimes it gets overlooked in diagnosing, I'm not saying that's it by no means, but that thing can do crazy stuff to fuel delivery if the insides gets goofed up.... Kevin www.kdfab.com | ||
| Björn |
Hey Kevin That's actually worth taking a look at eventough it might seem farfetched(spelling?) I know when the electrics get I mind of it's own it's a real handful fixing it! I've got this feeling that it's some weird electrical fault on this one so we'll check that out for sure. And for that tips I'll teach you how too put 2 dots over the o on an non swedish keyboard. Hold down the "alt" key and at the same time punch in the code 0246 in that sequence and voilá. Who knows it might come in handy  | ||
| Kds1 |
Björn, Check it out....Thanks for the tip, hope the Buell is that easy..... Kevin www.kdfab.com (Message edited by kds1 on August 25, 2005) | ||
| Opto |
Björn, I haven't heard mention of a new set of spark plugs actually being fitted, easier than getting your hands dirty. Next idea, swap the injector positions, feel the headers temperature for the misfiring cylinder (before and after) to check for a bad injector. (Message edited by opto on August 26, 2005) | ||
| Ingemar |
Seeing what you've done already, my next step would be to swap the ecm out, reset the tps and ride around to let the ecm learn the correct AFV. I'm not dead sure about this but I think the TPS needs to be reset when the engine is fully up to operating temperature. After the TPS reset and ride around for 10 minutes you might need to set the idle again. It should run smoothly from idle up. Lugging is not the same as running rough. Has the O2 sensor and headtemp sensor been checked yet? I'd check for intake leaks again, just to be sure. Good luck! | ||
| Bruceclay |
My first race kit had a bad ECM that had this problem. Ran like crap below 4500 RPM. | ||
| Blake |
cut and paste from PM Björn, Did you ever find a solution to the rough idle, erratically running XB9R? http://www.badweatherbikers.com/buell/messages/32777/142355.html My good friend Keith, Mr. Dark Horse Moto, is experiencing a similar problem. His XB9S will run great at wide open throttle, but elsewhere the rear cylinder misfires erratically. He's not getting any error codes and has installed new spark plug wires, installed new spark plugs twice, changed from race to stock ECM, removed PC-III & changed O2 sensor, installed new coil, checked connections, installed new intake seals, checked intake and rear cylinder head temperature sensors, reset the TPS twice. Next step is to verify TPS idle voltage, then if that shows good, he'll probably swap fuel injectors to see if the misfire jumps from the rear to the front cylinder. Keith hasn't checked timing on account of the electrical break-out box that will allow him to do that. The fact that it runs very well at WOT seems to indicate that timing is not an issue, and he's never fiddled with it, so it is tough to imaging it being the root cause, plus the front cylinder runs fine. Sure would be great to learn that you found the problem and it was injector related. Thanks, I'll post this to your original thread, so please respond there if you will. Hopefully this will benefit others who may suffer a similar problem. Cheers, Blake | ||
| Rkc00 |
Had something like this happen to mine. There is some setting about fuel pump pressure that the dealer reset. Fixed mine. Mike Long Island, NY 06 XB12X Black of course | ||
| Voltage_vector |
Had the bike sat unused for a long time? If so, it looks more and more like a blocked or partially clogged injector. Move the injector and see if the problem moves to the other cylinder is good advice. Also is it high mileage? I had a Ducati with Amal's, that had the throttle plate shaft hole actually wear oval once and caused irratic idle but was fine on the pipe. Good luck. | ||
| Mr_cuell |
Wow this is a cool thread - They should have a show about stuff just like this on the all Buell channel that speedvision should start. (I have a pretty elaborate dream world) This episode would be a cliff hanger, to be continued thing, leaving us all going, "What what is? Was it Sue-Ellen? No I think it was Bobby . . . " I'm staying tuned - What was it????????????  | ||
| Blake |
Björn replied via email as follows: Hey Blake! Thanks Björn! Your English is fine.  | ||
| Björn |
 I see alot of errors in my english above!  I blame that on replying just before my bedtime  Take care! /Björn | ||
| Alex |
Björn, give the rear cylinder head temperature sensor a try (maybe the intake air temp sensor, too). We´ve seen failures on that without an error code. Good luck Alex |
