Clicking/thumping from rear wheel after chain adjustment

[bleeble]

I finally got a chance to take my bike for a ride after working on it all weekend. I installed new shocks and adjusted the chain, among other things. Before, there was a light but noticeable bumping coming from the rear below 30 MPH (I could feel it in the pegs more than hear it). Now it's much more noticeable. I can feel and hear it until about 40 MPH. Around 15, it feels like I'm running over a small rock/bump. I can also hear a slight squeaking sound, possibly coming from the chain area. The chain was pretty loose before, but now it's in spec (or at least closer). I adjusted both sides evenly. it doesn't feel like the back tire is squirming at all. There's no clearance issues between the tire and anything else (and no rub marks on the side). The rear rotor/caliper aren't any warmer than normal. The thumping mostly goes away while accelerating; it's most noticeable on deceleration, regardless of which brake is being used (or engine braking). The frequency is dependent on the speed of the bike.

Could I have tightened the axle bolt too much? (I don't have a torque wrench.) I'm going to go loosen it a little bit and see if that makes a difference. Bad sprocket(s) or chain? I'll take a short ride without my earplugs to see if I can hear anything else.

[chef1366]

Chain is too tight. Find the tightest part of the chain and adjust that with the slack.

[bleeble]

You are correct. My dad suggested putting a brick under the centerstand and putting it in gear (can't believe I didn't think of that...). *sigh* At least my newbie mistakes have easy, free fixes.

Couple quick questions (pardon me if they're posted somewhere I haven't seen). I tried checking a parts fiche quickly and didn't see the answer.
-What size is the stock rear sprocket? Mine is 40.
-What size is the stock drive sprocket? (and is that what it's actually called?)

I know uneven chain wear/stretching is normal, but is this a sign that I should be looking for a new chain and sprockets?

[chef1366]

Could be. How far out are you on your rear wheel adjustments?

[chuckycheese]

Sprockets

The stock sprockets for your bike are 40 for the back and 15 for the counter shaft sprocket....or front sprocket.

You can easily check to see if your chain is stretched by the following method: Take a string and place one end exactly on one of the pins (the bumps on the sides of the links). Pull the string 21 pins and measure the string where the 21st pin is on the string. As I recall, it should be no more than 15.08 inches (or 15 inches for all practical purposes). If it's more (or close), I'd replace it.

[bleeble]

Could be. How far out are you on your rear wheel adjustments?

I'm between the fourth and fifth mark, counting from the back.

I'll try the string method after dinner.

[chuckycheese]

I'm between the fourth and fifth mark, counting from the back.

I'll try the string method after dinner.

Yeah, you should. The string method isn't something I made up...it's in the Suzuki shop manual (and I double checked on the 15.08 measurement). Based on the wheel adjustments you mentioned, I think your chain is stretched but still in the serviceable range. You should also take a look at the O rings on both sides of the links and make sure that the side plates line up with each other as you turn your back tire (on the center stand). Lastly, if the noise is intermittent, you could have a link or two that are binding. If that's the case, get a new one, for sure! (Or, it could break!!!)

[bleeble]

I'm just shy of 15 inches. I guess that means I should consider getting a new one before too long.

I was taking a look at Z1's 630-530 conversion guide. Is there any reason not to go with a 530 if I'm planning on getting new sprockets too?

Wow. Chains are $100? I think I may put it off until later in the season.

[uudfourty]

I think I may put it off until later in the season.

Next time you're going 50 miles an hour (or more) imagine what it would be like if the chain broke and wrapped up in the rear wheel.

[TheCafeKid]

I can say from experience that you likely have a high or twisted tooth. This is putting a bind on your chain, which would be the clicking/thumping sound you hear. Put you bike on the centerstand, in neutral, and spin the back tire by hand slowly, with your hand on it. You will FEEL the bind. As a fellow rider, I urge you to replace your chain and sprocket(s) imediately. This is NOT something that can wait till later, unless you dont plan on riding. Eventually, the binding will shave the rivet head off the chain links, and the chain WILL come apart, if you make it THAT long. One thing that will happen as well, as the bind becomes worse and the chain becomes more fragile, is that it will want to pull unevenly on the rear wheel, causing a bit of jacking action. Believe me, i KNOW this to be true, as I have done it Its a very un-nerving feeling trying to limp the bike home in this condition at 15 miles an hour, let alone having something happen at any real speed.

[bleeble]

*sigh* You guys keep making me spend money.

I was actually thinking about what would happen if my chain broke on one of my twice-weekly 320 mile drives today. I don't have or know anyone that has a trailer. Towing would be ridiculously expensive. I'd basically have to pray I was within walking distance of a bike shop and throw myself at their mercy... So yeah. I'd most likely be out a lot more than the $150 I'd have to pay for a 530 conversion.

Looks like I might be placing yet another order with Z1 tomorrow. (Does anyone else think that anything over $20 is an absurd price for a chain breaker?)

While I've got your attention, what chain lube do you like to use?

[Griffin]

I agree with everything posted about a bad chain or sprocket coudl cause what you're hearing. You should definitely check it out.

There is something else that can cause your symptoms as well. If one of your rear wheel bearings has gone bad and the race has broken, you will hear a clunking noise back there from time to time, particularly when accelerating or braking. The balls will be grating around and causing binding issues.

I know this from experience.

[Big T]

*sigh*

While I've got your attention, what chain lube do you like to use?

I used to use PJ1, which is a fine product, now I use Maxima chain wax, which seems even better.

BTW, things to never scrimp on:

1. Tires
2. Chain
3, Brake pads
4. Shocks

[robertbarr]

On a brighter note, you will regain that beautiful sound that a newer chain makes with new sprockets on a quiet bike (assuming you have mufflers). Right up to the point where wind noise takes over, it's just mechanical music.