COG Balancer shaft adjustment tips

Balancer shaft adjustment
	For a lot of people motorcycles vibrate, some more than others, it's the nature of the beast. Single cylinder 'thumpers' to six cylinder inlines, they all 'buzz' to one extent or another. The following comments are a few methods of fine tuning the ZG power plant. From: Scott Swenson WEIRD OIL LEAK It appears that an oil seal on my '87 Concours developed a leak over the winter. It's the seal around the balancer shaft (I think). It's the stationary shaft which sticks out of the case on the right side, near where your toe hits the brake lever. Any suggestions on how to replace this seal? My manual says NOTHING about it. Can it be fixed from outside, or do I have to split the cases? All comments welcome! From: David Svoboda The consensus is that it's an external seal, so the technique is to take off the clamp holding the shaft in orientation, and pick the seal out with a sharp instrument and needlenose pliers, then drive the new seal down over the shaft. Let it stand for a while, then readjust the balancer shaft as it describes in the shop manual. From: David Svoboda Last issue: someone a while back mentioned the balancer shaft seal, and having a leak there he was going to replace it. I myself have been living with a leak at that spot, and a year or so ago bought the seal, intending to replace it, and just never did. Well, last time I was under my Concours I had a close look at the spot, finally making plans to do the job. Hmm, there seems to be an oil pipe banjo RIGHT in front of the shaft adjuster. The process should be to remove the adjuster clamp, pry the seal out of there, drive a new one in, then readjust the balancer and reapply the clamp. Trouble is, it just doesn't look like I can get the clamp off of there without first removing the oil pipe. But the balancer is adjusted by idling the motor and listening to it as you turn the adjuster shaft. I definitely want that oil pipe connected when I do that. So I get the idea I have to remove the pipe (and hope I'm above the level of the oil-pan), remove the clamp, change the seal, let the sealing goop set, put the oil pipe back on, start the motor and let it warm up while holding the adjuster shaft, adjust the balancer by ear, mark the position of the shaft, take the oil pipe off AGAIN, put on the shaft clamp, then replace the oil pipe AGAIN. Yeesh, I don't have that many crush washers. From: David Svoboda Well, I finally did it. I was one of the many of use who had an oil leak at the bottom front of the motor at the balancer shaft oil-seal. Yesterday I finally got the time and gumption to change it. Tips: You gotta take the to-clutch oil-feed-pipe banjo-bolt off, since it's in the way, so get a couple of new crush washers ahead of time. ( note, see the next message. Ed.)* The adjuster screw is constrained to about 90deg, so don't worry about letting it turn while you're getting things off. To adjust the balancer (you can do so with the clamp in place but neither bolt torqued down) the engine has to be COLD, and idling. Start with the screw all the way to the right, start the engine and turn it left until you hear it. I was told to expect a clicking, but it's more like a loud chirping, and once you hear it it'll be a revelation, since that sound is a major contributor to the Concours running harmony. So you adjust it left until you hear the noise, then back off until the noise disappears, kill the engine, and tighten down the clamps. It made my engine noticeably smoother. I thought I had one of the "buzzer" Concours. It was only very smooth below about 4000, and got to be intrusive above 6000. I was considering lead-filled bars. No more. Now it's completely smooth at 5000, and not intrusive until the power runs out up near 9000. Yipeee! From: David Svoboda Well, of course, if it ain't broke, don't fix it. Indeed, if you don't need to change the seal, then you don't even have to remove the oil line, so tweaking the balancer would be a matter of loosening a clamp bolt and the holddown bolt, putting a screwdriver in the slot, starting the cold engine, and adjusting. Then retighten. No sweat. 15 minutes, tops, assuming you already have the right-side fairing off Now, whether you should mess with it or not, that's your own decision. Now that I know what it sounds like if it's too far in one direction, and what it feels like, vibration-wise, if it's too far in the other direction, I'll be tweaking it every valve-adjustment. I'm the inquisitive type, so if I were reading what I'm writing, I'd probably go ahead and turn it, and see what it sounded like. But that's just me. :-) From: David Svoboda > Dave, is the procedure simple enough you wouldn't mind describing it for > me, or should I just wait for the shop manual? Find the balancer shaft. It is the shaft sticking out the side of the motor on the lower right, near the front. It looks sort of like a shift - lever clamp, and there is an oil banjo bolt right in front of it. (The oil line is the one that sprays the clutch from inside the clutch cover.) To simply adjust the shaft, you don't need to remove the banjo-bolt. (That's only if you have to replace the shaft seal.) Simply loosen the shaft clamp, loosen the bolt at the end of the arm (if you don't the shaft won't turn even if the clamp's loose.) Now, start the bike. (Oh, it was cold, right? Don't do this on a warm engine.) Use a screwdriver on the shaft, and turn it slightly either direction, and listen to the whine from the balancer shaft. I've been told that the best spot is just as the whine disappears, and just a titch more. That seemed to do well for me. Find that spot, turn off the engine, and tighten the clamp and arm bolt. Voila! Another eliminator of buzz that I've done is to remove the mid-pipe exhaust tube mounting bolt. The rear bolts and header bolts are sufficient to retain the exhaust (I just passed 57,000 miles, with about 50,000 of them missing those bolts, if you don't believe me), and those hard-points really transmit engine vibration right into the seat and footpegs. From: Dave Wilfert Regarding adjustment of the balance shaft, I noted someone's post within the last couple of weeks that the real "sweet spot" for the shaft is 1) CCW to noise, 2) CW to silence, and 3) CW just a "little" more. I had adjusted the shaft per the service manual (engine cold with steps 1&2) during my first oil change, and it helped the buzz a little. Just changed the oil again and took the opportunity to try the again adding step 3. It did result in a little less vibration on my bike. From: Steve Moseley Well, I did the balancer adjustment also last weekend. My bike wasn't even buzzing, or so I thought until I did the balancer adjustment. What a difference! What little buzz I had at 4K was gone, or maybe moved down a bit to a lower RPM. I also did not remove the oil line, but really didn't have a problem turning the adjuster after it "broke loose" from being where it was for 9 years and 75,000 miles. I had to turn the adjuster a fair amount to the left before I heard the chirping, then backed off until it just disappeared. I didn't think I had had a vibration problem, but just did it for the hell of it, marking it first in case I made things worse. But the improvement was really noticeable in my case. I would bet that it's worth doing on all high mileage machines, because the chain* that drives the balancer probably stretches. *(It's actually gear driven, Ed.) From: Allan M. Carter > I was tinkering last night and decided to go after the balancer shaft, > but failed to locate it. Can you please give more explicit directions > on how to find it? > The balancer shaft is on the lower right, toward the front. There is a lever that screws into the crankcase at one end and clamps onto the balancer shaft at the other end. You need to loosen the clamp bolt and the bolt that holds the lever to the crankcase. The balancer shaft has a slot on its end for inserting a screwdriver and there is an external oil line very near the shaft. From: Andy Glass While changing the oil/filter last weekend I decided to take a crack at the much-touted balancer shaft adjustment. I pretty much followed the procedures outlined in COG page balancer shaft adjustment instructions. Everything went fine until I fired her up to do the actual adjustment. When I cranked the engine over, the balancer shaft (which I had already loosened) immediately rotated CCW and pretty much jammed itself solid in the full CCW position. Because access to the shaft is partially obstructed by an engine oil banjo fitting, I couldn't get good purchase on it with a screwdriver to unjam it. Meanwhile, the engine was making a hellacious screeching. OK, so I remain calm. I don't have spare crush washers, so removing the banjo fitting isn't an option. If I try the screwdriver on the balancer shaft any more I'm gonna strip the head. What to do.... I finally decided to tighten the pinch bolt on the shaft retaining arm, while removing the arm to block bolt on the other end, using the arm as a lever to break the shaft loose. Luckily, it worked and I was able to free up the balancer shaft. Then I start over on the adjustment process, and proceed to make the same mistake again, jamming the shaft full CCW... but at least now I figured out why it's happening. So, I break it loose again. It dawns on me that I need to have a screwdriver ON the balancer shaft holding it in place BEFORE I start the engine, thus preventing the engine from rotating it. Hmmm, seems someone forgot to mention this in the instructions :-( With this wealth of new knowledge, I was then able to adjust the shaft :-). I am relieved. EPILOG: I didn't notice any improvement in vibration... but at least now I know how to adjust the shaft. Might be worth monkeying around with some more, but it takes half an hour to remove and reinstall all the fairing plastic to get at the balancer shaft. Hey, at least it isn't any worse. ON A RELATED MATTER...Since I had things apart, I also decided to synch up the carbs, which hadn't been done since the bike was new (now w/~10,000 miles). Surprisingly, the carbs were all within spec, although some at opposite ends of their limits. The synch job was surprisingly easy, especially compared to my former KZ1000. The process literally took about 30 seconds. The only problem I encountered was reaching the center adjuster screw (to adjust #1/2 carbs to the #3/4 carbs). It is buried so deep under emissions crap, throttle cables, hoses and the wiring harness that I just couldn't get at it. The access is further complicated by the fact that the engine was fully warmed up and mucho mucho HOT (I've got burn marks on my knuckles to attest to this fact), as I'm told it should be when adjusting carbs. Though the carbs were still within spec I think I could have gotten them a little closer if I could have reached the center adjuster screw. Has anyone got tips to get at this center adjuster screw? I checked my Sears tool catalog to see if they have some kind of a flexible screwdriver, which seems like the only tool that can snake through the obstructions to get at that center adjuster screw - they don't. The engine idles a little more smoothly now, but here again I didn't notice much difference. No difference noted in off-idle or mid-range performance, which I think was already pretty good. Andy Glass '94 ZG1000 From: Rick Hall I've fiddled with the balancer adjustment on several bikes, yes including my own :) It does make a difference if it's way out of adjustment, but I can't tell much difference if I only have to adjust it a few degrees. Never hurts to check it though. What I have found is a proper carb balance and valve adjust makes just as much of a difference. When I adjust the valves, I concentrate on making each cylinder pair the same clearance. On the high side or low side of the recommended range, just make sure each cam lobe pair is the same clearance. Adjusting them to the center of the range is common sense though, you've spent a hour getting the fairing and valve cover off. May as well do it right. My routine is adjust the valves, button the valve cover back on. Hook up the mercury tubes, fire it up and adjust the balancer. Now check the vacuum reading, adjust as needed, the motor should be almost warmed up. Carbs are dry, the oil is warm, and any crud dropped in during the valve adjust is now in suspension. Drain and replace the oil and filter. For a warm fuzzy, replace the tank and warm the bike up fully. Recheck the carb balance and top off the oil level.

Balancer shaft adjustment

For a lot of people motorcycles vibrate, some more than others, it's the nature of the beast. Single cylinder 'thumpers' to six cylinder inlines, they all 'buzz' to one extent or another. The following comments are a few methods of fine tuning the ZG power plant.

From: Scott Swenson

WEIRD OIL LEAK
It appears that an oil seal on my '87 Concours developed a leak over the winter. It's the seal around the balancer shaft (I think). It's the stationary shaft which sticks out of the case on the right side, near where your toe hits the brake lever. Any suggestions on how to replace this seal? My manual says NOTHING about it. Can it be fixed from outside, or do I have to split the cases? All comments welcome!

From: David Svoboda

The consensus is that it's an external seal, so the technique is to take off the clamp holding the shaft in orientation, and pick the seal out with a sharp instrument and needlenose pliers, then drive the new seal down over the shaft. Let it stand for a while, then readjust the balancer shaft as it describes in the shop manual.

From: David Svoboda

Last issue: someone a while back mentioned the balancer shaft seal, and having a leak there he was going to replace it. I myself have been living with a leak at that spot, and a year or so ago bought the seal, intending to replace it, and just never did. Well, last time I was under my Concours I had a close look at the spot, finally making plans to do the job. Hmm, there seems to be an oil pipe banjo RIGHT in front of the shaft adjuster. The process *should* be to remove the adjuster clamp, pry the seal out of there, drive a new one in, then readjust the balancer and reapply the clamp. Trouble is, it just doesn't look like I can get the clamp off of there without first removing the oil pipe. But the balancer is adjusted by idling the motor and listening to it as you turn the adjuster shaft. I definitely want that oil pipe connected when I do that.

So I get the idea I have to remove the pipe (and hope I'm above the level of the oil-pan), remove the clamp, change the seal, let the sealing goop set, put the oil pipe back on, start the motor and let it warm up while holding the adjuster shaft, adjust the balancer by ear, mark the position of the shaft, take the oil pipe off AGAIN, put on the shaft clamp, then replace the oil pipe AGAIN. Yeesh, I don't have that many crush washers.

From: David Svoboda

Well, I finally did it. I was one of the many of use who had an oil leak at the bottom front of the motor at the balancer shaft oil-seal. Yesterday I finally got the time and gumption to change it.

Tips:

You gotta take the to-clutch oil-feed-pipe banjo-bolt off, since it's in the way, so get a couple of new crush washers ahead of time. (* note, see the next message. Ed.)

The adjuster screw is constrained to about 90deg, so don't worry about letting it turn while you're getting things off.

To adjust the balancer (you can do so with the clamp in place but *neither* bolt torqued down) the engine has to be COLD, and idling. Start with the screw all the way to the right, start the engine and turn it left until you hear it. I was told to expect a clicking, but it's more like a loud chirping, and once you hear it it'll be a revelation, since that sound is a major contributor to the Concours running harmony. So you adjust it left until you hear the noise, then back off until the noise disappears, kill the engine, and tighten down the clamps.

It made my engine *noticeably* smoother. I thought I had one of the "buzzer" Concours. It was only *very* smooth below about 4000, and got to be intrusive above 6000. I was considering lead-filled bars. No more. Now it's completely smooth at 5000, and not intrusive until the power runs out up near 9000. Yipeee!

From: David Svoboda

Well, of course, if it ain't broke, don't fix it. Indeed, if you don't need to change the seal, then you don't even have to remove the oil line, so tweaking the balancer would be a matter of loosening a clamp bolt and the holddown bolt, putting a screwdriver in the slot, starting the cold engine, and adjusting. Then retighten. No sweat. 15 minutes, tops, assuming you already have the right-side fairing off

Now, *whether* you should mess with it or not, that's your own decision. Now that I know what it sounds like if it's too far in one direction, and what it feels like, vibration-wise, if it's too far in the other direction, I'll be tweaking it every valve-adjustment.

I'm the inquisitive type, so if I were reading what I'm writing, I'd probably go ahead and turn it, and see what it sounded like. But that's just me. :-)

From: David Svoboda

> Dave, is the procedure simple enough you wouldn't mind describing it for
> me, or should I just wait for the shop manual?

Find the balancer shaft. It is the shaft sticking out the side of the motor on the lower right, near the front. It looks sort of like a shift - lever clamp, and there is an oil banjo bolt right in front of it. (The oil line is the one that sprays the clutch from inside the clutch cover.) To simply adjust the shaft, you don't need to remove the banjo-bolt. (That's only if you have to replace the shaft seal.) Simply loosen the shaft clamp, loosen the bolt at the end of the arm (if you don't the shaft won't turn even if the clamp's loose.) Now, start the bike. (Oh, it was cold, right? Don't do this on a warm engine.) Use a screwdriver on the shaft, and turn it slightly either direction, and listen to the whine from the balancer shaft. I've been told that the best spot is just as the whine disappears, and just a titch more. That seemed to do well for me. Find that spot, turn off the engine, and tighten the clamp and arm bolt. Voila!

Another eliminator of buzz that I've done is to remove the mid-pipe exhaust tube mounting bolt. The rear bolts and header bolts are sufficient to retain the exhaust (I just passed 57,000 miles, with about 50,000 of them missing those bolts, if you don't believe me), and those hard-points really transmit engine vibration right into the seat and footpegs.

From: Dave Wilfert

Regarding adjustment of the balance shaft, I noted someone's post within the last couple of weeks that the real "sweet spot" for the shaft is 1) CCW to noise, 2) CW to silence, and 3) CW just a "little" more. I had adjusted the shaft per the service manual (engine cold with steps 1&2) during my first oil change, and it helped the buzz a little. Just changed the oil again and took the opportunity to try the again adding step 3. It did result in a little less vibration on my bike.

From: Steve Moseley

Well, I did the balancer adjustment also last weekend. My bike wasn't even buzzing, or so I thought until I did the balancer adjustment. What a difference! What little buzz I had at 4K was gone, or maybe moved down a bit to a lower RPM. I also did not remove the oil line, but really didn't have a problem turning the adjuster after it "broke loose" from being where it was for 9 years and 75,000 miles. I had to turn the adjuster a fair amount to the left before I heard the chirping, then backed off until it just disappeared. I didn't think I had had a vibration problem, but just did it for the hell of it, marking it first in case I made things worse. But the improvement was really noticeable in my case. I would bet that it's worth doing on all high mileage machines, because the chain* that drives the balancer probably stretches.
*(It's actually gear driven, Ed.)

From: Allan M. Carter

> I was tinkering last night and decided to go after the balancer shaft,
> but failed to locate it. Can you please give more explicit directions
> on how to find it?
>

The balancer shaft is on the lower right, toward the front. There is a lever that screws into the crankcase at one end and clamps onto the balancer shaft at the other end. You need to loosen the clamp bolt and the bolt that holds the lever to the crankcase. The balancer shaft has a slot on its end for inserting a screwdriver and there is an external oil line very near the shaft.

From: Andy Glass

While changing the oil/filter last weekend I decided to take a crack at the much-touted balancer shaft adjustment. I pretty much followed the procedures outlined in COG page balancer shaft adjustment instructions. Everything went fine until I fired her up to do the actual adjustment. When I cranked the engine over, the balancer shaft (which I had already loosened) immediately rotated CCW and pretty much jammed itself solid in the full CCW position. Because access to the shaft is partially obstructed by an engine oil banjo fitting, I couldn't get good purchase on it with a screwdriver to unjam it. Meanwhile, the engine was making a hellacious screeching.

OK, so I remain calm. I don't have spare crush washers, so removing the banjo fitting isn't an option. If I try the screwdriver on the balancer shaft any more I'm gonna strip the head. What to do....

I finally decided to tighten the pinch bolt on the shaft retaining arm, while removing the arm to block bolt on the other end, using the arm as a lever to break the shaft loose. Luckily, it worked and I was able to free up the balancer shaft. Then I start over on the adjustment process, and proceed to make the same mistake again, jamming the shaft full CCW... but at least now I figured out why it's happening. So, I break it loose again.

It dawns on me that I need to have a screwdriver ON the balancer shaft holding it in place BEFORE I start the engine, thus preventing the engine from rotating it. Hmmm, seems someone forgot to mention this in the instructions :-(

With this wealth of new knowledge, I was then able to adjust the shaft :-). I am relieved.

EPILOG: I didn't notice any improvement in vibration... but at least now I know how to adjust the shaft. Might be worth monkeying around with some more, but it takes half an hour to remove and reinstall all the fairing plastic to get at the balancer shaft. Hey, at least it isn't any worse.

ON A RELATED MATTER...Since I had things apart, I also decided to synch up the carbs, which hadn't been done since the bike was new (now w/~10,000 miles). Surprisingly, the carbs were all within spec, although some at opposite ends of their limits. The synch job was surprisingly easy, especially compared to my former KZ1000. The process literally took about 30 seconds. The only problem I encountered was reaching the center adjuster screw (to adjust #1/2 carbs to the #3/4 carbs). It is buried so deep under emissions crap, throttle cables, hoses and the wiring harness that I just couldn't get at it. The access is further complicated by the fact that the engine was fully warmed up and mucho mucho HOT (I've got burn marks on my knuckles to attest to this fact), as I'm told it should be when adjusting carbs. Though the carbs were still within spec I think I could have gotten them a little closer if I could have reached the center adjuster screw. Has anyone got tips to get at this center adjuster screw? I checked my Sears tool catalog to see if they have some kind of a flexible screwdriver, which seems like the only tool that can snake through the obstructions to get at that center adjuster screw - they don't.

The engine idles a little more smoothly now, but here again I didn't notice much difference. No difference noted in off-idle or mid-range performance, which I think was already pretty good.

Andy Glass
'94 ZG1000

From: Rick Hall

I've fiddled with the balancer adjustment on several bikes, yes including my own :) It does make a difference if it's way out of adjustment, but I can't tell much difference if I only have to adjust it a few degrees. Never hurts to check it though.

What I have found is a proper carb balance and valve adjust makes just as much of a difference. When I adjust the valves, I concentrate on making each cylinder pair the same clearance. On the high side or low side of the recommended range, just make sure each cam lobe pair is the same clearance. Adjusting them to the center of the range is common sense though, you've spent a hour getting the fairing and valve cover off. May as well do it right.

My routine is adjust the valves, button the valve cover back on. Hook up the mercury tubes, fire it up and adjust the balancer. Now check the vacuum reading, adjust as needed, the motor should be almost warmed up. Carbs are dry, the oil is warm, and any crud dropped in during the valve adjust is now in suspension. Drain and replace the oil and filter. For a warm fuzzy, replace the tank and warm the bike up fully. Recheck the carb balance and top off the oil level.

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