| Author | Message | ||
     Dan_m |
I took a two days ride this weekend. Saturday i did aprox 500km, and for the last 50km i did that day, at slower speeds or traffic red lights i noticed a slight knocking sound from engine, but at that moment i wasn't alarmed. Ok, next day (sunday) when i fired up the bike to leave home, i immediately noticed that the knocking sound was stronger compared to day before so at that moment i realized that something is wrong. Being already pissed off on the bike (saturday the CEL appeared on the instrument cluster and on a quick investigation i discovered that the exhaust valve actuator died) i decided to go home on wheels (at a slower pace), being aware that this could seriously damage the engine. When i took off, from first moment i noticed a considerable power loss, as if the bike was running on one cylinder (it was barely gaining speed uphill, in 4th gear) In the end i managed to arrive home after a 300km ride, the knocking sound was still there but it didn't became stronger. The bike is a 2009 xb12x, it has 34000km on the clock, i bought it at 31000km. One thing i can add is that friday i changed engine oil and filter, previous owner used Motul 7100 20w50, i switched to Bel Ray v twin semi-syn 20w50. Do you think that this is the case of crankshaft failure? (I know that starting from 2008 the engine was improved) Or is it possible that the a lifter is causing this? Is it easy for myself to determine if there is a lifter issue, or it is better to leave the bike to someone competent? I like to work on the bikes i own, but i only do the maintenance (oil, brake pads, bearings, etc). Thanks! | ||
| Teeps |
Maybe it's just a bad spark plug. Can you post a sound clip of the noise? Was/is the engine running on both cylinders? | ||
| Arcticktm |
I can't give any brilliant insight into what the problem is, but I can virtually guarantee it has nothing to do with the oil change, unless you really messed up the oil change (like forgot to put in the new oil, or only put in 1 quart or something). Like Teeps said, need some more info to help any further, like verifying if both cylinders are running. I would think a crankshaft failure would be a lot more dramatic, but have never experienced one myself. | ||
| Hughlysses |
Crankshaft (actually the crankpin/rod bearings) failure starts out as a slight knock that gets progressively worse. If you have a small magnet handy, dangle it in the swingarm. If it comes out covered in filings, you've got a bad crankshaft. Alternately, drain the oil into a clean container (so that you can reuse it) and check the magnet on the stock drain plug. A very small amount of filings is normal. If the plug is covered, that's bad. I'm betting this is not your issue. | ||
| 96s2t |
If you used synthetic oil for the first time you might notice more noise. Change to good ol 20/50 HD Dino oil. It might make those noises go away. I did notice a big difference in valve noise with and without synthetic oil. | ||
| Dan_m |
@Teeps: I managed to upload the video on youtube, this is the link: https://www.youtube.com/watch?v=XCuC8r2dQdE&featur e=youtu.be I recorded only on right side of the engine, because i noticed that the sound was more pronounced on that side. The engine was running on both cylinders, i touched the headers with the gloves and smoke came within less than a second on both pipes. @Hughlysses: half an hour ago i checked inside the swingarm with a magnet, as you suggested: magnet was clean, nothing attached to it. Next step it will be to drain the oil and check the drain plug. Thanks to all for reply! | ||
| Hughlysses |
That doesn't sound very good, but it doesn't really sound like a bad crankshaft. HERE's what that sounds like: | ||
| Teeps |
Does not sound good; time for a tear down. If you're lucky(?) it might only be a faulty valve/pushrod lifter. | ||
| 96s2t |
Does not sound good at all | ||
| Hugie03flhr |
 (Message edited by Hugie03flhr on June 07, 2016) | ||
| Electraglider_1997 |
I'll bet it was caused by one of those oil sucking vampires that Romania is infested with. | ||
| Panhead_dan |
Could be a combination of two problems. If the primary chain is loose, it will make noise. The engine has a computer controlling it. Any number of things can cause it to go into skip-spark mode. Usually caused by excess heat. Do not panic | ||
| Hughlysses |
^+1. Don't tear into it quite yet. Check primary chain adjustment. Make sure engine primary sprocket bolt didn't work loose. If all that's OK, check compression on both cylinders. Dig further if necessary. | ||
| 96s2t |
Hughlesses might be right. The sprocket on my S2 came loose and made an awful rattling noise. Check that first. If that is the problem all you have to do is lock tight the shit out of it and button it back up. | ||
| Tootal |
Listen to those above. Compression check is cheap and easy and very informational! After you check the primary though. If all of those are good then I'd check oil pressure. Sounded like the lifters were collapsed. | ||
| Hughlysses |
Easy check for primary sprocket being loose: with bike idling, pull in clutch and put in first gear, ease out on clutch. If the knock gets less pronounced when you start to ease out on the clutch, a loose sprocket is probably your issue. If easing out on the clutch makes no difference, look elsewhere. The 08-up bikes have a one-use bolt to secure the primary sprocket on the crank. I don't know if it's a "stretch" bolt (which means you really shouldn't reuse it) or it's just a bolt with Locktite pre-applied. I suspect it's the latter, in which case you could remove it, clean both bolt and crank threads with brake cleaner, apply ample red Locktite, reinstall, and torque to spec. (Not sure what spec is on the later cranks.) | ||
| Teeps |
Dan_m Posted on Monday, June 06, 2016 - I recorded only on right side of the engine, because i noticed that the sound was more pronounced on that side. The engine was running on both cylinders, i touched the headers with the gloves and smoke came within less than a second on both pipes. Dan, It is worth the time to check the primary chain first. Only 2 screws holding the small cover on the primary cover. Note '08s didn't have a problem with the crank nut loosening, as the earlier XBs. Buell changed from a nut to a bolt. | ||
| Mark_weiss |
A bad connecting rod bearing generally does not cause power loss, at least not until things start to seize up or the bearing begins to disintegrate. Collapsed lifters do cause power loss as the valves are not fully opening. Maybe not opening at all. Fortunately, lifter issues generally do not cause further engine damage. Lifter noise comes from the right side. Unfortunately, the cylinder heads need to be removed to access the lifters. | ||
| Hugie03flhr |
I might be jumping the gun a little. After listing to the video again, I would agree it sounds like the primary The primary can make all types of noise depending on what is making the noise. Compensator sprocket or chain slapping. In rare cases, even the adjuster has blown apart. Your power loss might be the ECM thinking your engine is knocking. It will instantly pull the timing back to prevent detention. Good Luck (Message edited by Hugie03flhr on June 07, 2016) | ||
| Hughlysses |
^ These engines don't have a knock sensor. | ||
| Dan_m |
Thanks a lot guys for help. My only problem now is the limited time i have to investigate what is causing the sound. The update i can make for now is that yesterday i checked if the primary sprocket is loose, the way i checked it was as Hughlysses suggested -> i didn't noticed much difference at the knocking sound, maybe a very very little decrease, but i am not 100% sure. One thing that worth to mention about is that yesterday i had a hard time to start the engine. I mean, i tried 4 or 5 times, the engine was starting but within a second or two it was stalling. The only way to make it work was to help it with some gas. Another thing i did yesterday, was to drain the engine oil and check it again with the magnet: nothing attached to it, also the drain plug was clean. So next thing is to check the primary chain slack. I'm thinking maybe to remove the primary cover to be 100% sure that i'm not dealing with a loose sprocket. But, in this case, what could be the logical explanation for the power loss? The only thing i can add, is that i have the CEL light on, but traced this to a failed exhaust valve actuator. | ||
| Hughlysses |
Well, the clean oil is a very good sign. Stick with it; you'll figure it out. | ||
| Panhead_dan |
re: hard starting; Idle rpm with a warm engine is 1100. If it's set to 900 (common) it won't start without a little twist grip added. If it's set to run at 1100 rpm warm like it should be, do not twist the grip when starting. It causes problems like pre maturely fowled plugs. | ||
| Froggy |
Idle on his 2009 is computer controlled, so assuming the IAC is functioning correctly there is nothing for him to tweak or adjust, as it adjusts itself. | ||
| Reepicheep |
If it was a loose crank nut, it is a day and night difference when you load the clutch a little. Or at least it was on the M2. Idling, it would whack with kind of a subtle gong noise. Release the clutch enough to just BARELY load the drive train (light enough that I could still keep the bike from moving with just my feet on the ground) and it would go away. | ||
| Reepicheep |
And beware rabbit holes and red herrings. Lots of starting and stopping the bike (to listen to noises) makes it easy to foul a plug. So don't assume your starting problem is directly related to your noise problem. | ||
| 96s2t |
Not to discount your post but for all the 100+ bikes I have owned, restored and built and all the miles I have put on those bikes, the only plugs I have ever fouled is on two stroke dirt bikes and Kawasaki triples. Never on a four stroke and never on a V twin.   | ||
| Hughlysses |
^ that is no doubt true, but XB's are known to be prone to fouling the spark plugs if the throttle is "blipped" while the engine is cold. It's a fairly easy thing to check and fix if necessary. | ||
| 96s2t |
I will file that for my records. Thanks.  | ||
| Hughlysses |
No problem. It's a glitch in the fuel injection on these bikes; it apparently goes crazy rich if you blip the throttle when it's cold. Nice bikes! |
