Tapping/ticking noise from engine

[stubble!]

I posted a few months back about a loud tapping or ticking noise on my 1150. The consensus when I asked before was that it might be the rocker shaft end-play. I checked at the time, while performing a valve adjustment, the end play was well within spec, but I don't recall offhand if it leaned either way to the loose or tight ends of the window.

 

I'm about to do another valve adjustment, and I thought I'd take another stab at eliminating this, so I'm soliciting further comment!

 

Details:

 

It seems to be coming from the right jug, and it's intermittent, coming on and dying off while at idle. Its timing corresponds to engine speed. It's most prevalent when the motor's cold. It frequently shows up while dropping to idle. (I hear it a lot at the first few stops after leaving the house, when I chop throttle coming up to an intersection). It has been there since I bought the bike and doesn't seem to adversely affect anything.

[Joe Frickin' Friday]

is it the right-side throttle body? There's a metal finger that comes up against a stopscrew when you let off the throttle (i.e. when at idle). You would not hear this if you had the fast idle lever applied.

 

Next time you have the tupperware off, let the bike idle on the centerstand, and feel behind the TB for that metal finger. Try holding it firmly against the stopscrew to see if the rattle stops.

 

If that's the source of the noise, don't worry, it's not a problem.

[NoHeat]

A mechanic's stethoscope might help in pinpointing the source of noise. They sell for $15.

[Rob L]

Could be the timing chain adjuster. It is a hydraulic cylinder which operates using engine oil pressure. This would account for noise at idle and when cold. It is easy to remove and inspect and the replacement piston ass'y is not very costly. There have been several people on the board who have experienced the same noise, but usually from the left cylinder. Might be worth a look.

[Mark K]

Yes, are you sure it isn't the throttle body? Reach around with your finger and put some pressure on the pulley while it's making that noise. See if it doesn't stop. How many miles on the bike?

[stubble!]

Thanks for the replies. There are 20k on the bike, 11 of which are mine.

 

I haven't checked the throttle body, and will. I've been assuming it was in the valve train, just because it sounds like it.

 

I hadn't thought about a stuck chain tensioner either. I've long-replaced the left side tensioner with the updated version, but hadn't thought about the possibility of the right side being stuck or otherwise defective.

[Ken H.]

If you add just the slightest tension to the throttle (at the twist grip), just below where the RPM starts to rise, does the ticking stop? If so it's the throttle body.

[stubble!]

Well, I'm a little nervous now. I think it may be coming from the crankcase.

 

The stop screw at the throttle body is not it, I'm certain of that. There's no play at idle, and the rattle occurs at fast-idle too.

 

This weekend I did a zen-quality valve adjustment. Everything was still in great tune, but I finessed a couple of the valves and tweaked the end play (ugh, what a chore) on the right side. In short, the valve train is sweet.

 

I also inspected the right cam chain tensioner, and from what I can tell it's just fine. It's tensioning the chain nicely.

 

So then I buttoned it all back up and fired the bike. Yep, the rattle is still there. I don't have a stethoscope, but moving my head around the front of the engine it seems the noise may be coming from the crankcase. My impression is that it's in the right side toward the front, but I know sound is weird.

 

The sound is hard to describe. It's metallic, and has a definite rattling quality to it. It's not as precise as a valve tick would be, and as I've mentioned it's intermittent and scales in and out while idling cold. It's pretty loud.

 

Any more ideas from the gurus? I'm thinking it's time to take it to the dealer.

[Mark K]

An easy stethoscope.......Take your biggest screwdriver and stick the non-pointy end into your ear. By placing the pointy end on various parts of your engine, you should be able to zero in on the location of the noise.

 

(sorry for the overly-technical terms)

[ninermatt]

An easy stethoscope.......Take your biggest screwdriver and stick the non-pointy end into your ear. By placing the pointy end on various parts of your engine, you should be able to zero in on the location of the noise.

 

(sorry for the overly-technical terms)

Why can't you put the pointy end in your ear?

[CT_Rider]

Why can't you put the pointy end in your ear?

 

Because then the bike might start drawing up its own opinions on the rattling coming from his crankcase.

[AviP]

Why can't you put the pointy end in your ear?

 

Because then the bike might start drawing up its own opinions on the rattling coming from his crankcase.

[Mark K]

Did you ever find the source of your engine noise?

[Don_Eilenberger]

I had much the same noise - finally decided to do something about it tonight since I noticed it as a "rap" when at higher RPMs (above 4,500..) riding home from work tonight.

 

Took off the valve cover while the engine was still a bit warm (probably about 90F or so) and set it on TDC compression stroke on the right side - and found both rocker assemblies could be moved up and down a bit.

 

The intake one could be moved enough to make an audible click noise when I moved it.

 

I adjusted the rocker endplay to 0.0015-0.0020" on both. Was a bit of a PITA since it changed a bit when retorquing the head bolt you have to loosen. I finally got it by snugging up all the bolts and using a giant C-clamp to push up on the bottom rocker shaft block (the one you adjust).. With quite a bit of fiddling I was finally happy with the adjustment. I could easily move "rock" the shaft in the direction it is supposed to move, and could barely see it move up and down the shaft (can only see that by looking very closely for oil being squeezed at the bottom end.) That measurement ended up at the numbers above, and there was no more audible click when I tried moving them up/down by hand.

 

Checked the valve adjustment - the exhaust didn't change at all. The intakes went a tiny bit loose - brought them back to spec.

 

Buttoned it up, hooked up the TwinMax and warmed it up a bit. TB sync was PERFECT - didn't have to touch a thing. The sync also appeared more even over a wider RPM range than I had before, and the engine was now purring. No more tick/rapping noise from the engine.

 

Went for a short ride - and it's very nice, and stayed quiet.

 

I had checked the end-play when I adjusted the valves the first time - and it was within the range BMW allows - which is up to 15/thousands of an inch (0.015").. I suspect that for smooth running and minimum noise - trying for the smallest endfloat allowed is the way to go.

 

So - even though I wasn't the original poster - figured I'd pass it on while it's fresh in my mind. Finished up about 3 hours ago..

[steptoe]

Another cause of engine tapping/ticking, is loose ends in the pushrods - I get a few bikes in with the problem.

 

It's hard to check, as the pushrods need to be hot to feel the play by hand

 

BMW have changed the design, so maybe realise there is a widespread problem.

 

Pictures of a faulty pushrod - Second picture is a comparison of the old and new pushrod

 

 

 

[Don_Eilenberger]

Another cause of engine tapping/ticking, is loose ends in the pushrods - I get a few bikes in with the problem.

 

It's hard to check, as the pushrods need to be hot to feel the play by hand

 

BMW have changed the design, so maybe realise there is a widespread problem.

 

Pictures of a faulty pushrod - Second picture is a comparison of the old and new pushrod

Interesting - I'd assume these are quiet when the engine is started up cold? (Since you mentioned they need to be hot to feel the play..)

 

Mine also had a tap on startup - around idle - that would go away as the engine warmed up. The work I did last night seems to have eliminated both that noise and the tap/rap at higher RPMs. The engine is quite pleasant now at 4,500 RPM (used to feel it a bit there..) Rode to work this AM and my right hand didn't even go numb..

[Stan Walker]

Interesting - I'd assume these are quiet when the engine is started up cold?

 

That would exactly describe Jan's '96 RT. Purr's like a kitten when cold, has a tapping noise only when hot and only noticable at lower rpms. Runs great, smoother than my '02 RT.

 

I would never have even considered the push rods. I had always assummed they were one piece!!!

 

Stan

[Don_Eilenberger]

I ended up tonight doing the other side. Now that I had quieted down the right side - I could hear a bit of noise from the left side at 4,500 and up.. so..

 

Rocker arm end-float was around 0.010" (0.015" is allowed). At that clearance I can make a distinct CLICK noise moving the rocker up and down with my fingers.

 

With it between 0.002" and 0.003" you really can't hear a click, and the running engine sounds like a sewing machine.

 

Can't wait to ride it tomorrow - the right side made a BIG difference, I expect it will feel very nice now.

[sonofdennis]

I have the exact same noise in my 03 1150 RT. It has 40k miles only 6 of it mine. I have the valves adjusted as close to perfect as a full day will allow along with rocker end play set to the low specification limit. Though it made the heads quieter, when I use a mechanics stethoscope I isolate the noise in the right lower front of the case. Happend after bike is pretty soaked to operating temperature and comes and goes at idle. Did you get it fixed for good?

[Don_Eilenberger]

As far as I can tell - I did check it after a ride with my mechanic's stethoscope - didn't hear anything at idle or at higher RPMs.

 

Wonder if it could be the timing chain tensioner - that relies on oil pressure for tension - and if your oil is thinning out when it gets hot..

 

FWIW - I'm using Mobil-1 15W-50. (Hopefully not restarting an interminable oil thread..)

[Ken H.]

(Hopefully not restarting an interminable oil thread..)

Only that why would you use 15W-50 oil in a bike that calls for 20W-50 oil???

[Don_Eilenberger]

(Hopefully not restarting an interminable oil thread..)

Only that why would you use 15W-50 oil in a bike that calls for 20W-50 oil???

Because I ride it in temps below 50F..

[sonofdennis]

Yea, I'm wondering about timing chain tensioner myself.At 3k on up the motor is pretty quiet and smooth. It just purrs along. Idle is my tapping noise that comes and goes. I am using 20-50 synthetic so should not be thinning to much. However the earlier post about the push rod design change is interesting. Can you see the push rods with the cover off or do I have to pull the rockers?

[Don_Eilenberger]

Yea, I'm wondering about timing chain tensioner myself.At 3k on up the motor is pretty quiet and smooth. It just purrs along. Idle is my tapping noise that comes and goes. I am using 20-50 synthetic so should not be thinning to much. However the earlier post about the push rod design change is interesting. Can you see the push rods with the cover off or do I have to pull the rockers?

You can easily see them with the valve cover off (mine are the old style) - but you can't tell if any of the ends on them are loose - I think they'd have to be removed to do that. FWIW - my bike is a 2004 and it has the older style pushrods.

[sonofdennis]

Is changing a timing chain tensioner a 2 beer or 6 pack job? Has anyone had to replace the right side cam chain tensioner to quiet things down? I did the left some time back the the newer version told me by this group of folks and it did wonders for that side.

[Don_Eilenberger]

Is changing a timing chain tensioner a 2 beer or 6 pack job? Has anyone had to replace the right side cam chain tensioner to quiet things down? I did the left some time back the the newer version told me by this group of folks and it did wonders for that side.

I can't speak to the beer consumption since I don't know your wrenching skills or your beer consumption rate.. but..

 

I haven't heard anything that makes me think the right side tensioner needs to be replaced. The left definitely made an improvement - but that exposed some other rattles I hadn't heard before

 

So far - on bikes that had a rattle - I've found the rocker arm end-play to be out near the max BMW spec's for it.. which is an amazing 0.016".. Putting it back toward the minimum (I shoot for 0.002".. I'm happy if I get it to 0.003-4") makes for a wonderfully quiet running engine.

 

Did one Weds night at a tech session for our club. When we were done the comments were "My bike didn't sound that good new.." and "Wow.."

 

If you have noise in the engine - it's simple and quick to check for excessive end-float in the rocker arms. Take off a valve cover and push up/down on the rocker arms with the cylinder at TDC. If you hear a clear "click" - chances are very good that the end-float can be improved on.

 

JMHO.. and YMMV.

[sonofdennis]

Thanks, actually I have my right rocker clearance set to .005" and my left is at .003" and it did make the head noise go away. When I steth the intake and exhause area of the heads it pretty much quiet. Maybe I will check it again the next oil change to make sure my set point for the adjustment stuck. What annoys me is that it comes and goes at idle when the bike is soaked to operating temperature. It's fine 3k RPM or above. In fact with teh AL3923's it's very smooth at 3 to 4k cruise.

[allynr1100]

My bike also has this tapping noise. I have tried to adjust the right side rocker clearance but cannot seem to get the exhaust side closer than about .015. No problem with the intake side. Is there anything I am missing on adjusting this?

[Don_Eilenberger]

My bike also has this tapping noise. I have tried to adjust the right side rocker clearance but cannot seem to get the exhaust side closer than about .015. No problem with the intake side. Is there anything I am missing on adjusting this?

Not being smartass about it - you have loosened the head nut on that side correct? I'm sure you did, but just in case..

 

The one I did Weds night at our tech session was resisting adjustment on the exhaust on one side. It took a tad bigger rubber mallet - applied via a deep socket pressed against the bottom of the block we're trying to move to actually get it to finally close up. I found that having the three torx bolts just a bit snug seems to help keep it from rebounding and opening back up.

 

On some bikes a real help is a 6" C clamp used between the top of the rocker assembly and the moveable block - to pull it into position - but this was a GS with crash bars and the big C clamp was difficult to use on the right side because of the crash bars.

 

I did find that the gap tends to close up about 0.001-0.002" when I re-torque the head bolt - so I purposely left it at around 0.004" before torquing, and it ended up somewhere between 0.002" and 0.003" (0.002" fit, 0.003" didn't). As long as the rocker rotates freely I think you're good to go.

 

It is a fiddly adjustment. Hopefully it won't need doing for 100k miles or so. There isn't that much offset force on the rocker that I can see that would cause a lot of wear.

 

The last airheads used a plastic spacer at one end of the rocker and there were shims available (I still have some) to take up the play. I surprised me that BMW had done away with the plastic spacer on the oilhead design since it was an "improvement" for the late model airheads.

 

Next time I do one I'll take photos of the use of the big C-Clamp..

[allynr1100]

Thanks for responding Don. I did in fact have the head bolt loose. The assembly seemed to move easy enough I just couldn't get the exhaust side as close I wanted. I tried the C clamp but the one I had was maybe a little too big. I ended up putting a small hydraulic jack under the exhaust side of the assembly to push it up but that didn't work either. I didn't try hitting it with a mallet though.

[Don_Eilenberger]

Thanks for responding Don. I did in fact have the head bolt loose. The assembly seemed to move easy enough I just couldn't get the exhaust side as close I wanted. I tried the C clamp but the one I had was maybe a little too big. I ended up putting a small hydraulic jack under the exhaust side of the assembly to push it up but that didn't work either. I didn't try hitting it with a mallet though.

The soft mallet with the bolts just a bit snug seemed to do it for the one where I couldn't get the C-Clamp on.. might give that a try. When you use the C-clamp it's important that the bottom of the clamp only be on the moveable block, which isn't all that big. It's easy (DAMHIK) to get on the part of the head behind it - and then the C-clamp isn't going to do a thing.

[Eschelon1]

I get the same thing on mine, right when I start it up. It sounds like piston slap but it goes away after a few minutes. The only other time I hear it is if I bog it down with too much clutch from a dead stop.

 

[ninermatt]

I get the same thing on mine, right when I start it up. It sounds like piston slap but it goes away after a few minutes. The only other time I hear it is if I bog it down with too much clutch from a dead stop.

 

Your case sounds like a classic cam chain tensioner replacement candidate.

[stubble!]

I dunno, the left cam tensioner noise only lasts a few seconds, and it's very different from the noise I posted about, and what others are mentioning here. If you do have the brief rattle of the left cam tensioner, the replacement is a one-beer job even if you take it easy.

 

I'm interested to hear about the pushrod comments.

 

FWIW, my end play was about .005 when I first checked 6k ago, and I didn't touch it. When I adjusted it two weeks ago I brought it down to .003 or so. It's a tough one to get right. The intermittent ticking is still there though, unchanged since I bought the bike. I'm actually glad to hear of others with what sounds like the same noise.

 

The damn thing was phenomenal on the track last week, so I'm not complaining, and I'm not worrying about the idle noise for now.