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Discussion Starter #1
We talk about it, but I've never heard a detailed- for-the-layperson explanation of just exactly WHAT the KLUNK sound from the transmission is during shifting. Mine KLUNKS like HELL into first gear, even after 12k miles. It usually does it from first through third, but If I really try, I can finesse into second and third. If nothing else, it is an embarassment to have it work this way.

So what are the parts that are getting so abused? After 12k, I simply can't imagine parts slamming toegther like that are going to survive too long.

Could someone with the knowledge PLEASE take the time to explain just what is getting slammed so hard, and why?

Thanks-

B.
 

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Discussion Starter #3
so they are going to slam so damn hard all their life they are going to eventually send shrapnel everywhere? That's what mine sounds like going into first from a dead stop.
 

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Klunk is good.

It means that the dogs have fully engaged and you're ready to go.

Trying to quiet the cluck by foot shifting slowly or not completely only damages the dogs and leads to transmission damage.

If you keep the input and ouput shafts moving at close to the same speeds, the less the cluck. That means a brisk upshift, not speed shifting, but not loligagging either. On downshifts, revving the engine to match speeds will help too. When the bike is stopped, the output shaft is still and the engine/input shaft are rotating at idle speed. Fully clutching the bike will slow the input shaft a little, but it still moves due to some clutch drag. Holding in a couple seconds fully allows the shaft to slow maybe a little more and may help with the clunk, but don't ride the clutch, it'll wear out the bearings.
 

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Speaking of transmission damage: I was out on the Colorado/Utah border for a few day ride w/ some friends and shifted into 5th and it sounded and felt like the bike was being hit with a sledgehammer...but only in 5th gear and only when applying power. Made it back home by skipping 5th gear.

The report is that the dogs were extremely worn and that 4th was looking like it was going to fail shortly, so BMWNA is replacing the entire tranny under warranty.

Once again I gotta say: I got a lemon and it is in the shop more than I am out riding. I have started a dialogue w/ BMWNA and I am waiting to see what they are willing to do about the unending problems w/ this bike. Will keep ya'll posted.
 

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Discussion Starter #6
JCW said:
Klunk is good.

It means that the dogs have fully engaged and you're ready to go.
Baloney. There isn't ANYTHING good sounding as the tranny SLAMS into first gear while sitting at a stop light.

BAM! = NOT good.

I just got a GS and that thing shifts like someone built a tranny right. I'm tellin' ya, something is NOT good with this design. "Being hit with a sledgehammer" is an accurate description.
 

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It's probably happening on your car but you are far away, well insulated from the rear axle and there is much more mass in the drive line.

If we had a belt or chain from the tranny output shaft to the rear wheel you probably wouldn't hear anything. As it is, we have a shaft drive with splines, UJ couplings and a gear rear drive, so some backlash is to be expected.

I don't think clunks are anything to worry about compared to oil leaks and other problems. Nobody wears out gears or splines and whilst the rear drive crown and pinion is relatively large and beefy, it's the bearing or seal that will get you first.

If you slip the clutch out slowly at stops, you can take up the slack and mitigate clunks most of the time.



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While stopped and in neutral try holding the clutch squeezed for a minimum of two to three seconds before tipping from neutral to first and you won't here a thing.

Shifting from 1st to 2nd to 3rd takes a little more concentration: the clutch is just a very brief "brush" not a meaty squeeze; the shift itself, has to be snappy and precise, more of a "flick" than a poke. And the throttle must be consciously unspooled. Put all that together, just right, without thinking about it too hard and your bike will ride just like mine: smooth and quiet.

I hear lots of other bikes; like Japanese, shaft-driven cruisers and even some sport bikes make a lot more shifting noise than mine.
 

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Ive put 12500 miles on my 07GT in 10 months living in Seattle, this bike has always been a heavy shifter at low speeds and the gearbox has developed an annoying growl at idle sometimes very pronounced. The dealer says this is normal, any feedback on this.
 

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Well, mine clunks like hell too, but so did my old RT, and it never left me stranded so I got to believe it's just a Beemer thing. :confused:
 

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I, too, would like to know why the transmission clunks so hard at a full stop when I shift the bike from neutral into first gear, while the clutch is pulled all the way in. I feel the clunk all through the frame and in the handlebars. It is quite loud. It doesn't match the low force that I apply to the shift lever, so the energy to make that clunk must be pent up somewhere else. I looked at the "how transmissions work" links above, and elsewhere on the Internet.

Some of the posts above talk about how to avoid the hard clunk and whether or not it is good, but I am still confused about what causes it, and why it is so hard.
 

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My Kawasaki GTR 1000 had the same clunk going into first from a standstill and that was still going strong after more than 20 years and over 200,000km. It didn't have the loud clunks when changing between the other gears most of the time, however.

I have found that it is possible to reduce the neutral to first clunk to almost zero with the engine warm, by holding the clutch in as long as possible before engaging the gear. Mostly doesn't work on a cold engine or when the bike is new because the viscosity of the oil keeps spinning the input shaft even with the clutch disengaged. As long as the input shaft is rotating it will cause a clunk as the dogs stop it spinning to match the stationary output shaft.
 

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XMagnaRider said:
I, too, would like to know why the transmission clunks so hard at a full stop when I shift the bike from neutral into first gear, while the clutch is pulled all the way in. I feel the clunk all through the frame and in the handlebars. It is quite loud. It doesn't match the low force that I apply to the shift lever, so the energy to make that clunk must be pent up somewhere else. I looked at the "how transmissions work" links above, and elsewhere on the Internet.

Some of the posts above talk about how to avoid the hard clunk and whether or not it is good, but I am still confused about what causes it, and why it is so hard.
Clunk is caused by the mismatched speed of the input shaft and ouput shaft.

Pulling in he clutch should technically disconnect the crankshaft from the transmission but because of something called clutch drag, the input shaft still turns even with the clutch pulled in.

The colder the engine, the "thicker" the oil, the more clutch drag, the greater the mismatch, the louder the clunk.

The warmer the engine and the longer you hold the clutch in, the less the input shaft spins and the softer the clunk.

At least in theory...

Either way, don't baby the shifter. Firmly shift it into gear. The longer spent shifting, the greater the wear on those dog teeth.
 

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Bendagus said:
Ive put 12500 miles on my 07GT in 10 months living in Seattle, this bike has always been a heavy shifter at low speeds and the gearbox has developed an annoying growl at idle sometimes very pronounced. The dealer says this is normal, any feedback on this.
Might be the cam chain tensioner.
 

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Last fall I rented a Harley Softail Classic while on vacation in Hawaii.

After I got off the bike I told myself I would never complain about clunky shifting on my GT again!

Its all relative...
 

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Rebus said:
Last fall I rented a Harley Softail Classic while on vacation in Hawaii.

After I got off the bike I told myself I would never complain about clunky shifting on my GT again!

Its all relative...
:yesnod:
 

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Bendagus said:
Ive put 12500 miles on my 07GT in 10 months living in Seattle, this bike has always been a heavy shifter at low speeds and the gearbox has developed an annoying growl at idle sometimes very pronounced. The dealer says this is normal, any feedback on this.
Don't think this is the gearbox. I assume 'at idle' also means in nuetral with the clutch engaged. A lot of us, perhaps all of us, experience this. I believe it's due to the very uneven idle of the engine, which drives the clutch pack back and forth in it's basket, along with the noise of the lash in the main drive gear.

Flying brick engines used to make noise at idle, but the noise came from the tranny, which had an input shaft and an idler shaft, and the lash between the shafts was what we heard. K44 trannies don't have an idler shaft, so the tranny is not producing the noise, only the load. Noise and vibration should disappear when you disengage the clutch.

What's bothersome about your report is that it developed after 12k miles. My 07GT did it when new. This could be due to differences in the clearances between the clutch pack and the basket between our bikes. It's not an easy call, at least for me.
 

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Discussion Starter #18
After 12k miles, the butthead I am actually tried holding the cltch in for a three-count at a dead stop, then putting the thing in gear, and it went in way nicer. What a dork I am.

2nd and 3rd still seem to nip though- 4th never does. Can't hold a three-count going into 2nd and third, but they aren't NEAR as bad as 1st is....
 

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Brahma said:
Can't hold a three-count going into 2nd and third, but they aren't NEAR as bad as 1st is....
You wouldn't want to. What happens in second and third is different than first.

The longer you wait to shift into second and above, the greater the mismatch in shaft speeds and the greater the clunk. :deadhorse

Be quick and firm without "speed shifting."
 

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Brahma said:
After 12k miles, the butthead I am actually tried holding the cltch in for a three-count at a dead stop, then putting the thing in gear, and it went in way nicer. What a dork I am.

2nd and 3rd still seem to nip though- 4th never does. Can't hold a three-count going into 2nd and third, but they aren't NEAR as bad as 1st is....
Got some advice from a friend, and will try tonight after work: with clutch disengaged, put it in 2nd gear, then into 1st. 2nd will clunk, but lighter than into 1st, and once the tranny is stopped by putting into 2nd, going into 1st should be silent. Friend used it on rice rockets, should work for beemers, too.

3 count works for me, but anticpating when to do it is a challenge. I don't like holding on to a clutch while at a light, and I have nightmares about burning up throwout bearings. I guess now it's a 2 count, into 2nd, then into 1st. Getting complicated. :eek:ldster:
 
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