Topic: Ka-Lunk Under Load: Resolved

[burmashave]

I'm getting a knock under load, and I'm fearing bad news. Here's the details:

- Knocks under load when starting out or when slowly climbing a steep hill.
- Seems to be able to knock in any gear (will knock in 1st, 2nd or 3rd).
- Rate of knocking increases with speed; however, the rate seems too slow to be directly tied to a rotating part.
- Seems to go away as I accelerate.
- Knocking is worse with either brake depressed while under load.
- I can feel the knock through the footpegs.
- I've looked for loose parts, etc.
- The rear wheel seems to have no play.

This just started out of the blue during a 3 day trip. :-(  In terms of recent work, I had removed the starter and replaced the tires the week before.

[Burnboy]

have you checked the cam chain tensioner? Also is the main chain adjusted properly?

[andy750]

My knocking at low speed turned out to be worn final gear bearing (which means splitting the cases)....so drain the oil and check for any metal in there...other than that put it on centerstand and run it and go through the gears and see if you can hear where its coming from....check clutch for proper adjustment.

good luck
Andy

[burmashave]

Burnboy, the main chain is tensioned properly, but it's funny you should ask about the cam chain. I removed the tensioner when I pulled the starter. I cleaned, oiled and reinstalled it. I'm confident that I tensioned it O.K., but I'll double check.

Andy, I'm going to drain the erl today to check for gremlins.

[mystic_1]

- Rate of knocking increases with speed; however, the rate seems too slow to be directly tied to a rotating part.

- Knocking is worse with either brake depressed while under load.
- I can feel the knock through the footpegs.

How fast is the knocking, approximately?  You state the frequency increases with speed, I presume you mean ground speed.  Noise frequency is independent of RPM?  D

Can you describe the sound more, via some onomatopoeia?  Clunk?  Thunk?  Click?  Tick?

Do you only feel it, or do you hear it too?


Check for a bad link in you drive chain maybe.

mystic_1

[burmashave]

How fast is the knocking, approximately?  You state the frequency increases with speed, I presume you mean ground speed.  Noise frequency is independent of RPM?  D

It increases directly with ground speed, but the rate seems slower than what I would guess would be the RPM of a wheel. The noise seems to be independent of motor RPM. The klunk has a definite rate.

Can you describe the sound more, via some onomatopoeia?  Clunk?  Thunk?  Click?  Tick?

It's a "klunk".

Do you only feel it, or do you hear it too?

I can hear it as well.

Check for a bad link in you drive chain maybe.

mystic_1

That would be very cool. I'll double/triple check the master link I put in when I changed the tire. A chain problem would explain the rate of the noise, since the klunk seems to be slower than one wheel RPM.

I'm going to take Andy's advice and see if I can get it to make the klunk while it's up on the centerstand.

I'll report back this evening.

[HondaMan]

Check the master link closely in the drive chain?
How worn are the drive sprockets? I'm wondering if you might have a fractured roller on the chain somewhere, or the master link might be spreading, which they occasionally do.

[333]

Gotta be wheel related if it is relevant to ground speed.  Put it up on the center stand and spin the wheels.

[burmashave]

I've done a little more investimigating.

I changed the oil. There were no filings nor debris in the oil.

I tried to get the bike to replicate the knock either by hand turning the wheel or by running it on the center stand and using the brake to simulate a load. I couldn't get it to produce a knock that I could hear or feel.

The sprockets look good to me. On the other hand, the chain has many stiff links (that do not easily move back to straight from curved). I had oiled the chain not long before taking the trip, but my chain oiling leaves something to be desired. I spent all three travel days in the rain, so I'm sure this didn't help the chain.

As for why I wanted to check the master link, it was the only thing, besides the tire, that I had replaced before the trip. I wanted to make sure I hadn't bunged it up.

So, I lubricated the crap out of my chain and then took it for a short ride (it's raining here). I couldn't get the bike to knock, but I'll need a longer go just to make sure. The consistency of the klunk still makes me wonder if it is the chain.

Regardless, I'll order a new chain from Z1 tonight.

[Hush]

Oiling old chains makes bugger akk difference to them as the rollers stay dry inside, only way to truely get a total lube is to remove chain and curl it up, place in an old frypan with some chain grease and heat it, grease will then get inside rollers.
If you have an "O" link chain they don't require greasing (in fact it is not reccomended) but also they don't fit on the 500 and 550 models as there isn't enough by pass room in the chain casing to allow them to pass by.
Another thing to check is your chain guide, it's a bracket type thing in the front casing to stop an erant chain flying through your casing, these sometimes get out of whack and the chain hits them giving you a terrible knocking noise, beleive me I've had it and thought it terminal.
Def sounds like it's time for a new chain for you though, stiff links are a sure sign.

[BobbyR]

I get great deals on chain from Loud Fast Ugly. http://www.loudfastugly.com/
Pay no attention to the we are closed, just call him, and tell him I sent you.

[333]

A couple thoughts.  First, if you change the chain, change the sprockets.  They all wear at the same rate.  If you don't do this, it may only last 10% of it's regular life.

There is a easier way to lube the chain.  Start when it is warm, after at least an hours ride.  Spray the lube in on the inside of the chain, where it meets the rear sprocket.  Aim for where the inner and outer plates meet.  As the chain cools, it will suck the lube inside, where it needs it the most.  The next morning, wipe the excess off with a rag with WD40 sprayed on it.  This will keep the lube that didn't suck in off the wheel and the rest of the bike.  What is on the outside of the chain is unimportant.  And use a chain lube.  Oil will not stay on.

[HondaMan]

I get great deals on chain from Loud Fast Ugly. http://www.loudfastugly.com/
Pay no attention to the we are closed, just call him, and tell him I sent you.

Hey, Bobby, can you call Hondaparts-direct and make them do that, too?
I sure miss those guys. 

[andy750]

A couple thoughts.  First, if you change the chain, change the sprockets.  They all wear at the same rate.  If you don't do this, it may only last 10% of it's regular life.

Not wanting to start an argument but thats not my experience. I only change the front/rear sprocket when they look worn and not when changing the chain. I cant say it dosent alter the life of the chain but its not 10%. Since 2001 Ive gone 35 -40,000 miles on one set of sprockets (18/48) and gone through one Tsubaki Sigma chain (16,000 miles), one Tsubaki Omega chain (12,000 miles?) and an RK X-ring chain for the remainder...and just changed that and the sprockets (first time since 2001). i dont know how long you might expect an o-ring chain to last but those miles were not easy on the chain/bike and I was happy with the end result. Minimum maintenance on the chain - just lubed every 500-1000 miles depending on weather conditions and adjusted as usual.

This may not the best way but the rear sprocket was not shot.

cheers
Andy

[750goes]

Are the chain and sprockets aligned ??

[mrblasty]

I've heard random clunking sounds come from the center stand if the bumper is missing from your exhaust.  My buddies bike was doing something similar and it was the center stand bouncing into the chain as went down the road.

[754]

Jeez,, I hope they run their CREAKY OLD WIVES thru the greasey frying pan too..

 Oiling chain. simple hot or cold.. (running it an hour.. : )

 just put some gear lube on the inside of the chain.. ie upper part of lower run.. trust me, it will go thru the chain, if you ride it..
 Till you get a kink-free running chain.. all bets are off on any other causes. of the noise

[burmashave]

Are the chain and sprockets aligned ??

750goes, how do I check for chain/sprocket alignment? I think I had the front sprocket off when I replaced the tire (I can't remember why, though). The front sprocket has a little outdent, mebbe 1-2mm. Does this go to the inside or outside?

Also, I should have been more specific about what I did to the chain. I lubed it with chain lube (chain wax, actually).

[taxiscooter]

I had the same problem on my 750k7 earlier this year -- It thumped where I could feel it thru my footpegs as I slowed down -- Was very similar to what you described. I had just put a new chain and set of sprockets on it about 2 months before. I pulled the masterlink back out of it and put some chain lube in it before reassembling --- noise and thumping went away immediately --- no further problems -- hope this helps

[BobbyR]

Are the chain and sprockets aligned ??

750goes, how do I check for chain/sprocket alignment? I think I had the front sprocket off when I replaced the tire (I can't remember why, though). The front sprocket has a little outdent, mebbe 1-2mm. Does this go to the inside or outside?

Also, I should have been more specific about what I did to the chain. I lubed it with chain lube (chain wax, actually).

I have been aligning the chain by eye. I remove the rear bolt on the chain gurad and raise it. I then sight down the chain from the rear to the front. I look for alignment and to see if the links are hopping.

I am thinking about using a laser pointer laid on top of the chain over the rear sprocket and adjust it till the beam is dead center of the front sprocket. May be overkill.

[754]

Bobby, you have to make sure the sprockets are parallel, what you decribed is just making sure that you are aiming at centre of  front sprocket (not necessarily parallel).

[Duke McDukiedook]

Just like with bicycles, it is usually good practice to change your sprockets out with your chain.
If your sprockets are well worn, it will prematurely wear the new chain due to the sprockets not being within wear spec (chain and sprockets will wear together when put on new). Can you get away with old sprockets? Sure. Is it recommended? No.

[754]

Rears take 3 times as long to wear out as fronts..
 If you are changing rear for every chain, sell the used ones on here..

[burmashave]

Sprockets and chain are on the way. I've never replaced the sprockets, so I figgur it's high time to do it.

[jaknight]

Hey burmashave,

What's the latest developments?

How about bringing us up to date on things?  What's the skinny?

~ ~ ~ jaknight ~ ~ ~