Staylucky

Hi,

I've started to notice a knocking sound coming from the area of the front wheel when riding. I just replaced the headset with a brand new Origin 8 thinking the previous headset was shot. It didn't fix the problem.

This morning I had a little time before my commute, spun the tire and listened, no knocking sound but felt vibration moving up the forks and steer tube off and on as the tire rotated.

When commuting this morning, the knocking sound was back. Clearly this has something to do with that vibration when off the bike and knocking when on the bike. The question is....what?

I'm guessing I have worn out bearings in the hub, or I'm having an issue with some spokes, but wheels are something I've never been good with.

Any insight would be appreciated.

Cheers!

FBinNY 

Remove the wheel and spin it in your hands. If there's anything wrong you'll feel it through the axle. If the wheel spins fairly smoothly, then it may be a loose headset as this is the usual cause of front end knocking sound. Check the headset by holding the front brake on and rocking the bike forward and back. Look, feel and listen for any movement at the lower headset bearing.

BTW- it isn't rare for newly installed headsets to loosen up early on. Often the cups or crown race aren't pressed on all the way, and riding finishes the job creating some slack in the bearings.

Ex Pres 

Speedometer magnet?

AlphaDogg

I had the same problem as the OP at one point. I thought it was serious. Then I adjusted the magnet, and I felt stupid because the problem was so simple.

Al1943

The new headset might be loose. Hold the wheel in place using the front brake, then rock the bike front to back and see if you can duplicate the sound. Watch for any looseness between the fork crown and the head tube.

Staylucky

Thanks for the insight.

I tightened the headset and checked for play, seems fine. Took it for a quick spin and the knocking sound persisted.

I thought maybe the bearings in the hub were worn out. Took the hub apart, and found the bearings worn but not seriously worn. Decided to replace anyway since the bearings are inexpensive and the hub was apart already. STILL the knocking sound persists.

It happens at a single point of wheel rotation. The brake is not in the way, the wheel is quite true. I'm convinced I have an issue with a spoke. Unfortunately spokes are something i don't like messing with.

So I've decided that after 2 weeks of trial and error and no fix, I'm throwing in the towel and taking it in to the bike shop reluctantly. I'll let you know the result.

Al1943

What kind of rim is it?

Staylucky

It's an Ambrisio Alloy rim. Not sure on age, bought used last year. Have been working perfectly up until the last 2 weeks.

Al1943

If you don't have a tension meter have someone check the spoke tension. But loose spokes go ping ping ping, or click click, but not knock.
Take the wheel off the bike and see if you can make it knock without damaging the wheel.
Try riding with the wheel in the fork backwards to see if the knock continues.

Staylucky

Been slowly riding down a hallway of my house. It is more of a ping sound than knocking. I'm guessing it is spoke tension. I haven't had a chance to take it in yet. Maybe tomorrow

MudPie

I once found a spoke nipple floating around between the rim walls. I assume left there inadvertently during the build.

FBinNY 

If this is a very old wheel with a decent amount of mileage the spokes may be notched at the cross. These notches are tiny but can cause pinging when the wheel flexes. You can test for this by squeezing the crossed spokes past each other and listening or feeling for the notch.

Many years ago I had a real diehard front wheel that after 10s of thousands of miles was notched and pinging so much it drove me crazy. In the end I cured it by sliding small scraps of fabric into the cross. it cured the problem, but didn't look so hot.

rekmeyata

Try simple fixes first before going to more difficult ideas.

Check that magnet as others have mentioned first, then check the quick release as mentioned below.

No one even mentioned the possibility that your front quick release may not be tight enough. The quick release lever should start to feel resistance when it's half way between open and closed, you can adjust this by turning either the release lever or the opposite nut till you get the resistance at the half way point. Make sure that when you turn the lever or the opposite nut that they are equal distance from the fork blade, in other words you don't want the quick release side to be closer to the drop out then the other side or vice a versa. Then tighten it securely in the upward position parallel with the fork blade and just a hair behind it, position is not important as is the tightness but this is the pro look, you can put it any position you like, some think having the arm in the horizontal position pointing toward the rear is better so it doesn't accidently hook on to something and flip open.

Then check the headset to make sure it's tight, this can be done by locking up the front brake only with the bike on concrete and try rocking the bike forward and backward to see and or hear if the headset is loose.

Check to make sure you wheel is true and not striking either the left or right brake shoe at some point.

Loose spokes will not cause a knocking sound, this will sound is like a pinging sound instead.

jim p

If you can get another wheel and stick it on. If the noise disappears then you know that the noise is coming from the wheel.

Staylucky

Hi everyone,

Thank you very much for your help. I finally got to the bike shop today. The mechanic said it is a tension problem in the spoke. I couple of them needed tensioning and the wheel needed a little truing. The sound is gone and the wheel is spinning a little straighter.

Big shout out to Sweet Pete's in Toronto for the fix up!