Lower engine knock

[pekingduck]

A big-end bearing died in my Honda CB175 many, many years ago. I remember only that (a) it wasn’t cheap to fix; and (b) it made a very solid and regular knocking noise (not at all faint) which is what told me something was wrong.

Older Honda singles and twins had roller bearing rods and ball/roller main bearings, so they were pressed together, with replacement parts largely unavailable, so they were expensive. They also had centrifugal oil filters on the end of the crank rather than paper filters. For the most part, current singles are still pressed together.

[zirconxi_imp]

Doing some detective work while in Covid19 lock down, I am looking at the parts diagram and notice that other than 1 bearing each for the conrod, there are 6 sets of bearing for the crankshaft. Could it be that the right hand most crankshaft bearing having problem? since when bike is on side stand, i believe the oil might not reach the right hand most crankshaft bearing. The conrod bearing should be bathing in the oil when turn, but the right most crankshaft bearing could be starving for oil when on side stand. But having 6 bearing to hold the crankcase shaft, will 1 out spec bearing causing noise?

And there's also some thing that look like roller bearing on the balancer shaft which i believe is on the right hand side as well. Will the balancer shaft give the same noise when their bearing fail? I believe the bearing for the balancer shaft are sold as a set for the balancer set, since there's no separate part number for the balancer's bearing. But anyway, please do share the results of the finding once dealer had a look at your bike.

[SportsterDoc]

See posts 14, 18 & 33

http://cb1100forum.com/forum/showthread....adjustment

[zirconxi_imp]

Interesting... the 5 minutes warmup engine sound sure sound similiar to this thread that SportsterDoc share... But too bad the original thread starter doesn't mention if he had solve the problem....

See posts 14, 18 & 33

http://cb1100forum.com/forum/showthread....adjustment

[airenping_imp]

Hello all, Got the call from the dealer to remove the oil pan and inspect. First off, when I left it I made sure to run the bike and had everyone there listen and understand when it does this. They called me a few days later and said "even though you just replaced the oil and filter (no miles on the bike since that oil change and maybe 10 minuets of run time) we didn't see an metal in the oil. (not surprised) We looked at what we could with the pan removed and nothing obvious. We suggest you pick up the bike and ride it to see if the condition improves or worsens and let us know"

I called back and asked why no further diagnoses was offered and they said, "well how far do you want to go with this and the money to tear the engine apart?"

I asked about calling Honda Co. for added help and based on the description Honda offered maybe timing chain tensioner is the issue. I had a local tech look at the video and that was the first thing he said without any back story. Needless to say I picked it up and brought it home. I'm a little confused why they would give up with diagnosing the issue and tell me to ride it with an internal engine noise. I'm not a fan of riding a bike when an engine could fail and lock up. I'm not trying to be over dramatic either, but the risk seems a little too high for my taste.

So for a $50 part and my time I guess I will be taking a look and replace the tensioner.

And yes the metal I saw could still have been from break in, but who knows at this point. And also I'm sure it will be asked because I have been already, I'm not going to force a shop to do a repair after that phone call, who knows what you will get. I am a bit sad this is how it went down since I bought 4 brand new bikes from them over the years and I was planning on leaving them my RC51 for an oil leak repair when the CB was done, but that ship has sailed.

Stay tuned

[PowerDubs_imp]

I was about to say get a new dealer. I would also follow up with a well written letter to corporate saying exactly what you said- bought several bikes and yet received a half a**ed answer from both incompetent mechanics and management and will take your business elsewhere as well as posted online. No excuse for that behavior.


Sent from my iPhone using Tapatalk

[E11even_Hunnit]

post pics of that RC51

[Houtman_imp]

I bought a new 2004 RC 51 , the Nicky Haydn Edition . Not an easy bike to ride here in the mountains of Western NC. My neck and back was killing me , even after I put Helibars on the bike. Sold it after a few thousand miles. When living in Upstate NY the bike was great.

[pekingduck]

from airenping
"Hi all. ...... the engine started making a knocking noise from the lower end on the right side. .......... Oddly enough when on the center stand it was quiet. But as soon as I left it on the side stand for a minuet it started knocking again. Once it starts knocking it doesn't matter if you stand it upright, still knocks. "
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Ping, what happens if the noise starts up, and the bike is leaned to the right side? And what happens when the clutch is pulled in each of these scenarios?

[airenping_imp]

Yeah the RC51 is the Nicky Haydn edition and is a rough ride for sure. Have to be very carful with parking lot maneuvers, because I cant bend my wrist under the tank just yet.


Leaning, and clutch no change. I haven't tried center stand and running though the gears tho. I really wont do anything else till I try the tensioner to make sure no more if any damage happens.

Thank you all