I'll side with the chain and/or sprocket camp. The cost over the life of the parts is small compared to gas. How is the spring rate adjustment on the shock? You know the chain gets looser as the shock compresses?? Did you check the chain adjustment on the center stand? On my 2012 F650 with only a few thousand miles on it the chain is noticeably tighter in one spot. Adjust the chain to the upper (looser) end of the spec and crank the spring rate up to double what you usually run. If a sprocket is out of round it shouldn't pulsate if the chain is loose. If the pulsating is still there put it back on the center stand and adjust the chain to as loose as it will go. Turn the wheel in the direction of forward motion and watch the chain as it comes off of the front sprocket. If a link is stiff you will notice it as the chain comes off of the small diameter front sprocket. GH
I did an oil change last week and checked the drain plug, clean as a whistle. I will run through all those other things on the weekend. So Cambi, what you gonna do about it? I thought you only check the chain on the side stand?. Well, that was what i did. Side stand, check, move bike forward a fraction, check, move bike forward etc. I will try all your other points on the weekend too. Thanks everyone for all you ideas and input Grant
If you are checking the chain adjustment on the side stand you probably need to push the bike a couple of miles to get a good reading and then remember where in the two mile trip the chain was the tightest! Checking it on the side stand is bull shit! GH
I agree with the above. I just changed my chain and sprockets after more than 40,000kms more as a preventive measure as they were good to go for a few more thousand kms. I did chain adjustments by the book (only a couple) on the side stand but also on the center stand and found no noticeable difference. I am convinced they say side stand because the bike was available with the center stand being an option. I think your chain cleaning (a dirty job but you'll be going link by link which is good) might turn up something. Be sure to take off your chain guard and clean the crap out of the front part where the fling of grease builds up inside it. Clean along the top run of the chain so you will never have to worry about getting your fingers jammed, simply clean on the top run by rotating the wheel forward and clean the links closer to the middle.
So you had this symptom once before and a new chain cured it. You have it again and you are worried it might be something else. I don't know why you detect it only in 5th gear, but I think it should lead you to believe it is the same problem. I still think it is a chain issue. It is not unusual for chains to get frozen links in them, one of those signs it should be replaced. I have never been able to fix them. It might be hard to detect on the bike, at least loosen the axle to get a lot of slack in the chain to look for it. The chain is made by CZ for BMW. Even the "new version" is not as good as many others. Worn or not, at some point you are going to have to replace it, so not like throwing money away.
You are right Gary, replacing the chain and sprockets might fix the problem, just trying to figure out what the actual problem is though . There is a user here who lives not far from me, he has a DID ZVM2 116 links for sale, appropriate?.
"I don't know why you detect it only in 5th gear" It is probably just the sweet spot where the load on the drive, rpm, and road speed are best to notice it. GH
"I did chain adjustments by the book (only a couple) on the side stand but also on the center stand and found no noticeable difference. I am convinced they say side stand because the bike was available with the center stand being an option" How do you find the tight spot when adjusting on the side stand? The tight spot on my chain is probably 1/2" tighter than the loose spot. I guess if I didn't have the center stand I would adjust the chain to the slack end of the recommended spec. No way I would be rolling the bike back and forth to find the tight spot! GH
Thats the correct chain, new I hope. Did the dealer change the sprockets with the first chain? If not you are probably due. As to the tight spot, some swear you got to find it. Maybe I just do not understand it well enough to worry about it. What causes it? The only thing I can think of is the spline hole is not concentric with the diameter of the sprockets. Piss poor quality control if you ask me. The problem appears to me is if 1 is 16 tooth and other a 42 tooth, a ratio of 2.6225 to 1, the tight spot is a moving target even if you locate it the first time. At least do 3 complete revolutions of the chain to try to pin it down.
I had a DID O-ring chain sometime back that was almost new and started making weird noises when riding. It had a master link so I popped it off the bike and "worked" each link ... I found three consecutive links were only the "left' pin was very stiff ... (bad-good-bad-good-bad-good) my suspicion was that whatever piece of equipment that DID had that metered the lubricant into the links did it on a link-by-link basis and that the "left" injection tube momentarily got an air bubble in it or something similar... To their credit, when I called DID and explained the problem they send me a brand new top-line chain (better grade than the one I had originally bought) and a postage-paid mailer in which to mail back the bad chain so they could evaluate the failure. Something like that might be going on here....
JR has good luck with suppliers! Regarding another poster's question about side stand style chain tensioning, yes, I did wheel the bike around to find the tight spot. Yes, that is another reason why I think it is a little ridiculous to use the side stand method when you have a center stand.
Harmonic. On mine at roughly the speed described, while wearing the half helmet the chain is slapping at about 160 beats/min. There is some sort of pulsing through the drive train. But only in a very narrow rev range. I hear it crystal clear slapaslapaslapaslapaslapa I figure it's a good noise. While it's making a noise it's going. God knows that's not always a certainty with one of these.
I would be more than happy if that was the case Snowy. Would there be any practical way to test this?.tighten chain as much as possible, somehow stop the chain slapping temporarily so I can hear it for myself?
I have the same symptom, but don't see it as a problem at all. Feels like two instruments playing slightly off key with eachother on the same note. Just a product of all the vibrating parts in the machine.
So Cambi, what you gonna do about it? It's not that strong at the point of being worried - yet. I am still on a well maintained OEM chain kit so tomorrow, I planned to fit a BMC HP2 sport filter - removed rear wheel, check bearings - work on the chain, in depth cleaning, check each links and lub as many mentioned that it could be the issue. Test ride and revert back over the weekend - Changing the kit will be a mulled wine winter project.
I know this will sound facetious, but... Change gears. The DR 650 has this horrible jack hammer effect at 60 in top gear (with standard gearing and carby) and the simplest solution was to change gears. Avoid the rev range where the counter balance shaft, and the crank seemed to hit a harmonic and quite literally the bike humped up and down in time. After changing the gearing and playing with the carb and every thing else, it isn't THAT big a problem, but it's still there. I don't notice it any more because I just don't ride it in that rev range at that speed as a direct result of the effect it has. Around town, unless I'm in the process of decelerating, at 72kph I wouldn't generally be in 5th gear on the BMW. But if I do lug it along in 5th or 6th at 60~80 it has all sorts of vibrations and noises. It's simply too low in the rev range. I don't think there's anything specific you can DO about it. It is what it is. It's like people complaining about noises in a 5 speed car gear bow at 60 or 70 kph. You aren't meant to be in 5th (overdrive) at anything under 80kph anyway. The torque loading on the bearings in the box exponentially increases as the speed decreases. Vibrations will be more pronounced and failures accelerated. Many years ago I learned this the hard way, doing many long distance trips in 4x4s with high overdrive boxes and V8 engines. 5 gearbox failures in 5 years taught me a lot about gearboxes. The first thing being gearboxes don't like high torque loads on overdrive gears at low revs. Not when you do 2500kms in 24 hours in ambient temps at 35 C and 80% humidity like I was doing several times a year. The F800 box has 5th and 6th gear as over drives. 4th gear is a 1:1 from the clutch basket, if I read the right specs. 2500rpm is low revs for a parallel twin.
No, not facetious at all. For the most part I do just avoid that rev range...doesnt mean the problem is gone though. Really all I wanted to know is that this isnt a huge problem causing any kind of major damage. From what I have read on here its not really a major issue.
I've been trying to find it, because I read somewhere about final drive vibrations on another forum. But I can't remember where I read it. I was looking for info on something entirely different at the time and it caught my eye because I knew mine vibrated like the guy described. Basically he had a bearing in the final drive section of the box go. At the time I thought "Oh great, just ANOTHER problem to face.." but it hasn't got any worse over the last 30,000kms so maybe it's not quite what he described. There is also the rather funny side effect of reading about all these noises, vibrations and problems. You start hearing them, feeling them, and you're dead sure it's going to go wrong with yours. Like a mechanical hyperchondria. I rode mine after reading about yours and I was dead sure it's worse. So I switched to one of my other helmets that has much better sound insulation. I can feel it slightly, but I can't hear it now. Problem solved. It's a BMW...what could possibly go wrong?
Good point. I've got a buddy that had an F650GS just like mine. Two up with his girlfriend and the chain jumped teeth on the sprocket because he was remiss with his maintenance. No worries, pull over and tighten it. He rode more than 10,000kms with a ding in his front rim that put the fear of God in a few who observed it. No worries, when he changed the tire he gave it a few judicious whacks and he was good to go. Same with plugging his tires. Use the plug like it says in the instructions and you're good for the life of the tire. I rode his bike one time and complained about the steering head bearings, he looked at me sideways and put another 5,000kms on them. Yes, he was prepared and carried tools with him, he just didn't feel the need to fret and worry about things. Smart man.
