I just rode 800km and before I left, I spray oiled and readjusted my chain and topped up the engine oil levels and did tyre pressures.

After I had gone about 500km I started to hear a knocking sound that only occured when the rear tyre was trying to go faster than the engine, when I was coasting up to traffic lights.

I have a feeling the chain is flopping too much and hitting the exhaust or something. It all felt fine when accelerating, or riding at constant speed.

I couldn't see any marks or telltales when I pulled into fuel stations and put it up on the centrestand to have a look.

Before I start taking covers and things off, can anyone think of where I should start looking?

I've also noticed that the bolts that hold the rear sprocket on are very close to the swing arm adusters... I can't even squeeze my fingernail between the bolt and the swingarm and I think they may even touch under load...

can anyone tell me how far the sprocket bolts shoud be from the swing arm? Photos would be gret so I can picture what it should be clearly... I'll post photos of the way it is in a few nights when I can get back to the bike again.

Cheers!

 

Sound like somethings not right. Maybe a colapsed bearing? Or a spacer not on the right side?? You should have a few mill gap between the sprocket bolts and swing arm unless your rear wheel is out of line??

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Mines an 89 F-K

 

Further to that - You say the bolts that hold the sprocket on are very close to the chain adjusters. Do you mean the aluminium plate at the rearmost part of the swing arm? I've supplied a photo so you can see how far back (or not) my wheel is. You can see where my adjuster marks are so can compare them to yours. My chain has been on the bike now about 6 or 7k miles with scottoiler fitted. Is your chain a standard length? How many miles has it done? Are you running out of adjustment lines? You could just have a worn out chain and the knocking you're feeling on over-run may just be a tight link. Time to change it I think.

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How many km/m are on the chain and sprockets? How much static play is there in the chain? Makes is somewhat difficult to get a good picture of the issue without knowing some particulars.

Possible things to look for (in no particular thought order):

1. Binding link in chain, happens under high heat if not o-ring or x-ring chain. ( I know you said you just oiled and adjusted).
2. Unaligned chain. look at the inside of the outer chain links, if there is more rubbing on the rim side than on the swingarm side, then this would suggest that the chain is misaligned or that the right side bearing could be failing. (chain adjusters locknuts are 16 ft. lbs. or 2.2 kgf m torques specs)
3. Hows the cush drives? The rubber things in the left side of the rim. This could be flexing too much.
4. Worn teeth on the front sprocket or rear sprocket.
5. Front sprocket nut loose.
6. With bike on center stand, check for slap of rear rim bearings by wiggling it left to right. Doing this by hand wouldn't be that indentifiable unless the bearing(s) were real bad. You might have to wedge a piece of wood between the tire and swingarm, then watch closely the area around the right side spacer or leftside for movement.
7. Spacer between right side of swingarm and caliper not seated correctly.
8. Axle nut loose (65 ft. lbs. or 9 kgf m torque specs)

I'm not an expert but I have had that feeling in my chain before. The distance between the swingarm and any nut when near it is about 1.5 to 3 millimeters. Static chain adjustment is between 0.6 and 1.0 inches or 15-25mm. No matter how much chain wax I used, it didn't help. I ended up getting a new chain. I know that doesn't solve your problem but I was just noting how I corrected my chain problem.

Best of luck Triangle.

 

When I measure the gap on mine I get about 1/8 inch or around 3 mm between the arm
and the bolt.

I had a similar noise when I first got my bike used. I would hear an uneven growling like sound when backing off the throtle when comming into towns or down hills. I could also feel it thru the shifting lever. It went away when the motor was driving the rear tire. After 12,000 miles I replaced the chain. The noise was still there. Last year I replaced the chain myself and used the master link and clip that came with the chain. That fix the problem.

I think that in my case the master links used by the shop were either peened too tight or made by a different manufacture than the chain. If the master link is not at the same pitch as the rest of the chain it may causie a rumping noise each time the link pass the front sprocket. I could never locate the problem with the bike on the center stand and rotating the tire by hand. I could however hear something.

If your chain properly adjusted and the wheel is alined correctly, check to see if anything is touching when the bike is on the center stand. If things check out OK, you may have the same problem I had.

If using the clip type master link it is extreamly important as to what direction the clip goes on.

Good luck!

 

turns out it was just a dry chain... drowned it in chain wax and all's good... except the yellow wheel is in need of a clean

my sprocket holding nuts are much closer to the swingarm than in those photos... will think about replacing the bearings and checking the spacers in the next while. Thanks for all the valuable input!

I prolly close the masterlink too tightly whenI put it back together too

 

Good to hear more lube fixed ya'.

I have a knocking upon initial acceleration that is definately coming from my chain/sprockets. I've put ~ 30k kms on the bike since I've owned it on the chain/sprockets that were on th ebike when I bought it. I still have 2 notches visible on the adjusters. I know there are some tight spots on the chain, but I still seem to be able to adjust to the right amount of slack at the tightest spot. Do I ned to replace the whole she-bang now?

I do see some clean/rubbed spots on the links. In contrast to inner plate vs outer plate, my rubbing is on the inner part of the peanut as opposed to the outer part of the peanut. There's shiny metal on the chain on outer plates on the side closest to the sprockets. The outer edge of the plates are normal (oiled) looking.

How many kms should a chain/sprocket combo be expected to last?

 

That shiny metal is a sign of wear. It is coming from somewhere. When a chain gets worn, the rollers loose their diameter. Even though the chain is not streached, it is spent due to lack of lubercant.

The smaller rollers tend to climb up on the teeth of the sprockets, wearing them out too.
Could be the noise you are hearing.

If I get more than 1 inch of side play in my chain I replace it. That is a sign that the inside of the rollers and the pins they ride on are worn.

Always replace both sprockets and chain at the same time. This will prolong the life of all three.

Those rubber "O" rings hold the luberacant in the rollers. If they are dry, the chain is dry even if it looks oiled. I use chain wax. The wax is delivered in an alcohal soulition and penetrates the rollers. The alcohal evaporates off leaving the wax. The wax stays on longer in the rain also. I will never go back to anything else.

As far as chain life, it depends on how you ride. Popping wheelies, doing burnouts and banning gears at red line, all streach the chain. If doing all of those w/o oil or wax, the chain dies real quick. I wax my chain every 600 miles or so, or when I start to seeing shiny rollers. Shiny roller = dry roller, in my head. I got 15,000 miles out of a chain once and replaced it before it had a lot of wear. If a worn chain breaks it usualy does one of two things. (1) Spits out of the back, leaving you out someplace ayway from home. (2) The front sprocket packs the chain into the engine case. This breaks the case and the motor is either trashed or you have to pull the motor and weld up the hole and fix what ever else is broken. Hopefully you don't get road rash in either case.

A can of chain wax is far cheaper than a chain or fixing broken cases.

 

Great info.

I got a closer look @ my chain yesterday and noticed I'm well past the red zone according to a little service sticker on my swingarm. I'm about a cm past the red "replace" zone. I still have two knotches on the adjusters visible (like Steve with the pic of the gold chain above) but the inner most knotch with the arrows is too far towards the back of the swingarm.

New chain and sprockets are in order for me. Local dealer has some after market steel ones for ~$200 CDN. I don't think I'll continue to ride it until these parts get replaced ... now that I know what the sound is and how worn out my chain is, it messes with my head everytime I swing a leg over my old faithful CBR ...