crankshaft balancer backlash adjustment

Thread starter
kDiqq_imp said:
Matt,

Please continue to throw out ideas!! It helps a ton, especially with how regularly I am wrong :P I just passed up 1200 miles.

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1200 miles! Oh that just hurts... i can't logically think up a way for your oil pump to be making that noise only after 2:30 of warming up till hot and still actually oil the engine and it hasn't been spewing out metal when you change your oil. I think once someone gets the oil pan off they are going to find something that i normally put on my shelf of wtf. It could be anything from main bearing bolt loose to a missing wrist pin clip... but it's something that is fine at first then goes through the twilight zone then is fine when hot. That's a fun one i wish i could get my hands on it.
 
Kdiqq - what oil are you running in there now? Mine made a similar sound when I used 10w40 for my 600 mile oil change. Replaced the filter and used. 10w30 and the noise was gone.
 
the noise you hear in the video is also on my bike, check well catalysed exhaust system, I'm pretty sure is the problem, you should remove the final exhaust part and check if the smoke filter vibrates.

Angelo
 
Angelo, I isolated the noise with a stethoscope. Its coming from the oil pan, in front of the catalyst. I did check though, thank you.

Todd, it made this noise from day one. Just progressively got louder and louder. I've gone to Amsoil 10-40 and the clutch feels far better and every 'normal' noise has gotten quieter lol just this one seems to be getting louder with time

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Todd_K_imp said:
Kdiqq - what oil are you running in there now? Mine made a similar sound when I used 10w40 for my 600 mile oil change. Replaced the filter and used. 10w30 and the noise was gone.
Yes sir, mine made the exact same noise as in the video he just posted after my first oil change. There is a video on here from DBUSTER with the exact same noise. Do a search and take a few hours to read through the thread. The oil is not returning fast enough causing the knock in your lower end. If it was a mechanical issue it would not come and go. Flush your crankcase once or twice with 10-30 full synthetic and change oil filters, the cheapest fix you'll find. One quart of oil stays in the oil cooler so be sure to flush the system well.

Edit:
Here you go:::
Getting ready for the riding season greeted by bad sounds....
 
I'm extremely unconvinced of this. In its warm up period is when it's happening. It passes through being a 30w. I do believe that changing the oil may make it quieter, but it won't fix it. And I know that using the weight of oil suggested for my climate is offering better protection than a 10w30, especially a Honda brand oil.

That being said, thank you for providing the thread!

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Eh, F it. Putting 10w30 on order if it keeps me from bringing her to the dealer... I hate hate HATE that this eliminates the noise...

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Can one of you guys explain just what piston slap is and what it sounds like and any bad things it does? Thanks. I gots to know ;)
 
kDiqq_imp said:
I'm extremely unconvinced of this. In its warm up period is when it's happening. It passes through being a 30w. I do believe that changing the oil may make it quieter, but it won't fix it. And I know that using the weight of oil suggested for my climate is offering better protection than a 10w30, especially a Honda brand oil.

That being said, thank you for providing the thread!

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Eh, F it. Putting 10w30 on order if it keeps me from bringing her to the dealer... I hate hate HATE that this eliminates the noise...

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Use OEM filters for flow rate
 
Lord Popgun_imp said:
Can one of you guys explain just what piston slap is and what it sounds like and any bad things it does? Thanks. I gots to know ;)
I'd be happy to! The best example I know of it is in aluminum motors. Specifically GM aluminum motors. To be out simpky, the piston at any given moment is too small or the bore too large and the sides of the piston are knocking against the bore. Since the rings have room to expand, a compression loss is not experienced. Usually this occurs because the pistons and sleeve are made of different materials and these materials have different coefficients of thermal expansion. So, in the case of steel sleeved, aluminum motors, the bores will 'open up' when it's cold and as it warms up, the block will expand just enough to bring that gap closed enough to stop the slapping. Sounds awful, but typically doesn't do any damage.

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Thans KDigg!

I've heard of piston slap, but never really knew what it was, or the causes. Great explaination.
 
Had a Honda civic that developed piston slap at 50k miles. On Cold mornings it sounded like a bearing was going. Never had any real problems up trough 205k when I sold it.
 
kDiqq_imp said:
Lord Popgun_imp said:
Can one of you guys explain just what piston slap is and what it sounds like and any bad things it does? Thanks. I gots to know ;)
I'd be happy to! The best example I know of it is in aluminum motors. Specifically GM aluminum motors. To be out simpky, the piston at any given moment is too small or the bore too large and the sides of the piston are knocking against the bore. Since the rings have room to expand, a compression loss is not experienced. Usually this occurs because the pistons and sleeve are made of different materials and these materials have different coefficients of thermal expansion. So, in the case of steel sleeved, aluminum motors, the bores will 'open up' when it's cold and as it warms up, the block will expand just enough to bring that gap closed enough to stop the slapping. Sounds awful, but typically doesn't do any damage.

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I'd be happy to! The best example I know of it is in aluminum motors. Specifically GM aluminum motors. To be out simpky, the piston at any given moment is too small or the bore too large and the sides of the piston are knocking against the bore. Since the rings have room to expand, a compression loss is not experienced. Usually this occurs because the pistons and sleeve are made of different materials and these materials have different coefficients of thermal expansion. So, in the case of steel sleeved, aluminum motors, the bores will 'open up' when it's cold and as it warms up, the block will expand just enough to bring that gap closed enough to stop the slapping. Sounds awful, but typically doesn't do any damage.

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The early GM 5.3 and 4.8 motors were bad about this. My 2000 Silverado 5.3 has it. On a cold morning, it'll clatter about 45 seconds and quiet down.

My 13 CB was clattering to my alarm, so I am glad I found this thread. I adjusted the backlash per the manual and she quieted down considerably.
 
the_undecider_imp said:
kDiqq_imp said:
Lord Popgun_imp said:
Can one of you guys explain just what piston slap is and what it sounds like and any bad things it does? Thanks. I gots to know ;)
I'd be happy to! The best example I know of it is in aluminum motors. Specifically GM aluminum motors. To be out simpky, the piston at any given moment is too small or the bore too large and the sides of the piston are knocking against the bore. Since the rings have room to expand, a compression loss is not experienced. Usually this occurs because the pistons and sleeve are made of different materials and these materials have different coefficients of thermal expansion. So, in the case of steel sleeved, aluminum motors, the bores will 'open up' when it's cold and as it warms up, the block will expand just enough to bring that gap closed enough to stop the slapping. Sounds awful, but typically doesn't do any damage.

Sent from my Z30 using Tapatalk
I'd be happy to! The best example I know of it is in aluminum motors. Specifically GM aluminum motors. To be out simpky, the piston at any given moment is too small or the bore too large and the sides of the piston are knocking against the bore. Since the rings have room to expand, a compression loss is not experienced. Usually this occurs because the pistons and sleeve are made of different materials and these materials have different coefficients of thermal expansion. So, in the case of steel sleeved, aluminum motors, the bores will 'open up' when it's cold and as it warms up, the block will expand just enough to bring that gap closed enough to stop the slapping. Sounds awful, but typically doesn't do any damage.

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The early GM 5.3 and 4.8 motors were bad about this. My 2000 Silverado 5.3 has it. On a cold morning, it'll clatter about 45 seconds and quiet down.

My 13 CB was clattering to my alarm, so I am glad I found this thread. I adjusted the backlash per the manual and she quieted down considerably.
By "manual", do you mean shop manual? I checked my owners manual supplied with the bike, and can't find anything about this adjustment. :huh: Indeed no mention of the balancer at all, even in the maintenance schedule. That seems odd to me... I don't have any of the symptoms, but it would have been nice for Honda to tell owners how to do it should the need arise. I guess they expect it to be set right at the factory, and should never need service?
 
Yes, adjustment procedure is in the service manual. Also, it is posted in the How to section on the board here.
 
Today I removed the drain with a cold engine and with a video camera for inspection I watched the smoke filter, everything is ok then I tried changing the oil 15w40 with a 10w40 oil and filter, I warmed up the engine and then with a long screwdriver I tried if the filter vibrated ... but anything all ok, I finally made a trip of 100 miles but I did not hear more noise, Baker!!!!Maybe when I put the bike on the side stand the oil goes on the left and interior noise you hear more, and when I put the motorcycle on the Centre stand the oil suppresses noise!!!!!?!?!?!?


Angelo.:huh::biker::biker::thanks:
 
Lord Popgun_imp said:
Can one of you guys explain just what piston slap is and what it sounds like and any bad things it does? Thanks. I gots to know ;)
I had a 454 chevy with piston slap. Sounded like strong lifter clatter which decreased and went away as the engine warmed up (aluminum pistons expanded). Did not at all sound like a lower end knock. Low end noise gets worse as the engine warms up and oil thins out.
 
:huh:
Huh! You’re never too old to learn something. I never heard of bores getting smaller as the block heated up. I kinda still doubt it. As a block heats up it gets longer and wider. The cylinder bores get larger exactly proportionally. Aluminum expands more than steel or cast iron with the same increase in temperature. Typical hot rod lore includes the knowledge that forged aluminum pistons expand quite a bit and when given proper clearance, piston slap will happen until they heat up and take up proper clearance. Actually all engines have piston slap: The wrist pins are offset toward the thrust face so the piston (the largest and most critical bearing in the engine) rotate the skirt fully against the cylinder bore to take advantage of the full skirt for bearing area under the firing stroke. Conversely the pistons attempt to rock the opposite way on the intake stroke. This is very small movement and not heard on a good motor. Modern hypereutectic pistons have recipes in their casting materials, which minimize the difference between thermal expansion of the cylinder and pistons making piston slap loud enough to hear rare.

I believe motorcycle owners that aren’t gear heads worry overmuch about noises, especially in air-cooled motors. Large flat cast covers and fins have harmonics and can amplify noises. Honda is so aware of this I’m sure every cover, fin, every casting is engineered around this and many other parameters. They have done an amazing job and the casual rider has no concept of the depth of their research and knowledge over the years. There is violence going on inside these motors. Controlled explosions, valves opening and closing rapidly, pistons coming to the top only to be yanked back to the bottom at great rates. There will be noise, and we love all those noises. All motors have their signature noises. It is wonderful we can experience this. Try not to worry.

I haven’t got my shop manual from Helms yet but why are people calling the balancer an “engine and transmission balancer”? All inline fours vibrate in a vertical plain at twice the frequency of crankshaft rpm. Nothing in the transmission needs balancing.
 
What about the possibility of some kind of throttle body sync issue ? Just a WAG. If you have ever heard a 4cyl or a CBX way out of sync , it sounds like the eng will come apart.
 
I was a mechanic in a Honda, Yamaha, BMW, BSA and Greeves dealer when the CB750 came out. The first ones had cable splitters, the one throttle cable from the twist grip pulled the 4 separate carb cables out of this splitter. Carb syncing was tedious and lasted for a couple of high speed blasts. All the fours had vacuum ports to plug gauges into. All of the big four quickly changed to common throttle shafts which helped a lot. There is a couple of aspects to throttle synching. First, the idle mixture had to be adjusted so that all cylinders fired at idle. If the air mixture was off, the throttle adjustment could be right and the idle would still be terrible. At an idle everything is so close to being closed and off it is hard to get perfection. Also those bikes had two ignition systems. All fours fire 1,2,4, 3. 1 and 4 had a set of points and coil; 2 and 3 had a set of points and coil. Timing could easily be off between those two sets of cylinders. Also valve lash is an important component of a stable idle. I’ve always been a proponent of setting valve lash to minimum specs, seems to make sense, less room to bang components and maximizing valve lift. However a stable idle on all those old fours was best achieved with the middle of the lash specification or at the upper end of it. This was particularly true of the Kawasaki 900s/1000s. I have a great appreciation of My CB1100 as I stare at my dusty sync gauges hanging above my workbench. Hale, My Ural even has FI. The chance of your CB1100 being out of sync much is slim or none unless some busy fingers have been in there. After a while, I got to care less what my Kawasaki’s idle sounded like as long as all the throttle slides reached the top at the same time and under load it ran fine on all four cylinders. A heat gun is a good tool to see if all the TBs are working ok. When you first start it up, get the heat gun out and check each head pipe at the same distance from the head. They should be in the same ballpark.
 
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