New bike and this week I seem to get all the complications.
:-)

Back wheel --> when it turns/spins, it makes a knocking/tapping sound, once per revolution.

At first, it sounded like wheel/rim hitting the fender/mudguard or the brake pads, but I don't seem to be able to locate it.

The sound/tapping can be felt through the frame (back triangle) too, once per revolution - the effect gets worse if the bike is held horizontally, so that the back wheel spins horizontally. Also, no obvious wheel lateral movement - quick release lock seems tight enough.

Has something come loose a bit and should be adjusted? - this is a new bike, used for commuting before sunrise!

Many thanks.
Archie

If you're sure it's not related to the rim or tire hitting...

What about bearings/chain-to-cassette issues?

Or...this is perhaps the STUPIDEST thing I've ever had go wrong on my bike...my rear reflector got loose and would knock against the rear forks, it was unbeliveably hard to locate for two reasons

A. I never in a million years thought to check the reflector.

B. It would hit, I would look, but it had just been knocked back into place so there wasn't anything to see until just before it would hit again. It only fell out of place in the last 45-30 degress of rotation.

If the noise is occuring in only first gear then i would check the rear derailleur is adjust correctly. I have seen on more than one occaision a single spoke in the rear wheel sticking further out than the rest due to poor wheel tension and it would knock on the rear mech. Also check to make sure the rear mech hanger is also alligned correctly.

Yip, I'm guessing it's a lose spoke. If a wheel isn't tensioned right during the build process, the nipples can losen up over a few rides.

Good luck!

Thank you for your replies - the knock/tapping occurs during free wheel - I don't think I can hear it when in gear! - ie just free rotation of the back wheel, I think.

I will check the spokes now. If there are other suggestions then please don't hesitate.
Cheers
Archie
Just got back home and it was even darker this morning at 6:15 :-)

I have the same problem, except it only happens when I'm ON the bike. When I spin the wheel off the bike, nothing. My bike is not new like the OP's, but I did recently have a broken spoke replaced. Related?

Knocking only when you are on the bike is probably loose spoke. The replaced spoke has probably settled in to position and now needs tightening.

If the knocking is only when the wheel is freewheeling ( check by turning the pedals while the wheel is spinning) it is probably a sticking pawl in the freehub. Take it back to the shop to fix since it is a new bike.

Thanks AndrewP! (and to the OP for posting -- I was too lazy to start my own thread!)

So I checked the spokes on the back wheel and they all seemed to be pretty tight. Am I possibly missing something?

Pluck the spokes and listen to the pitch. They should all be the same. Pay particular attention to the one that was replaced. Sorry I dont have any more ideas.

AndrewP

As you suggested it seems that my free-wheel tapping is from the rear hub/gears . . .

The other thing I've noticed is that if I BACK PEDAL, then I get a similar tapping sound from the back hub area.

By the way, my spokes do NOT all sound the same pitch . . . . but I guess this is another story about correct wheel setup . . . Makes you wonder what the heck do these bike shops do when selling new bikes to the general public.

My bike (MTB) is only 3 weeks old . . . I won't name/embarass the Original Manufacturer . . . but guys please keep a tight conrol on your dealers!

Regards
Archie

Get it back to the shop, for the freehub fix. It may be simpler for them to swap the whole wheel, and that may also fix the inconsistent spoke tension problem. Get them to check the spoke tensions with a tensiometer.

I'd check your rear hub bearings, if your bike is inexpensive and the wheel bearings are not sealed, a ball bearing may have escaped the race and is rattling around. These seldom have enough grease when new. No biggie though, just repack your hub. The shop you bought it from should do this free. If youre on your own, you need to invest in some cone wrenches to do it. Another possibility, if the noise seems to come from your rim and not the hub is a loose spoke nipple rattling around inside the rim. Maybe one got dropped inside during the wheel build. Most likely a loose bearing in the hub though.

Thank you for the replies. I'll take it back to the shop now for a check as you all suggest . . . I'll update you on the dealer's response. Thanks again.

Regarding my situation... I plucked the spokes and there was a huge variety in pitch so I gave-up on that approach. The good news is that the sound has gone away!

I have been riding an older Trek with a circa 1992 7-speed freewheel setup on the rear and recently have experineced an intermittant tapping or ticking. At first I thought it to be a spoke, since the wheel is not really very well tensioned. But the sound would come and go and seemed to depend on how hard I was riding and in what gear. After a bit of poking about we found a slightly bent rear axle - the noise is probably due to the bearings being slightly trashed. Need to take it apart for the final diagnosis....

Sorry I didn't see this thread before... I know that knocking sound well.

9x/10 its the seam where the rim is joined smacking against the brake pads. Its such a small defect and happens so fast that you can hardly see it, even if you try hard. If you spin the rim slowly I bet that when you get to the seam you will see is pretty close to the brakes on one side. If not, forget I ever wrote this :o

I just developed a very similar problem on a new 2005 Lemond Poprad (~450mi)

The tapping/ticking comes from the wheel, most likely the rear, but it is very hard to tell. It is only sounding when I am on the bike riding, even when coasting. I can not duplicate on the stand, it seems the wheel needs a load to produce the sound.

I am very certain it is not:
-wheel hitting rubbing anything, brakes, etc.
-debris in tire or tread problem
-chainline related

I checked the spokes and they are seem to all ping the same tone, none seem loose. But right now that remains the primary suspect. I don't have the experience to know how to find what spoke to check.

I listed to the front and rear bearings (put one end of rod on the wheel axle and the other end against ear). The front is like butter. The rear had a bit of roughness in sound, but no repetetive noise.

I'd like to take it back to the LBS where I bought it, but right now need it every day for commuting, so its going to be a while. The tap, tap, tap noise when riding is getting quite irritating.

Al

Yea, so I found this thread because yes, my real wheel is ticking like mad. Anyway, two of my spokes are very loose. I ride this bike to work every day - so will riding on it until next weekend really damage the wheel or should I get off of it right away?

Also, I don't know if I trust my LBS for big jobs - is this simple enought that I shouldn't worry about taking it to them? Honestly, taking it some place else would be a real *****. Also, how much do you think it would cost to tighten a few spokes? I can do everything else on my bike, but never touched my wheels.

If you don't have a spoke wrench yet, get one. Park makes an inexpensive multi-size one. A pair of needle nose pliers will work better than nothing. Your LBS may have the Park spoke wrench.

I had a strange clicking noise emanating from what I thought was the front hub of my mountain bike several months ago.
Checked the front hub (just repacked a couple of months before). It seemed fine.
Totally repacked the headset. Still had the noise.
Thought about my 15 year old Phil BB and thought it could be that. Nope. Still like butter.
Concluded that the noise was produced under heavy load (pulling a trail-a-bike).
The culprit was a couple of loose rear spokes that tightened up in about 30 secs. with the help of the spoke wrench.
And to think I had all kinds of expensive solutions floating around in my head and it was as simple as this :) .

Thanks for the reply, but how can I tell if all the spokes are the same tightness?

Update on the knocking I had. The LBS was puzzled too - checked spokes, hubs, etc. Eventually they found it was the tube valve tapping on the rim with every revolution - thats why it only occured under load. A valve nut cured the problem.

Al