Single/Track Bike - "Knocking" Headset/Chain

Pushiron Jud

Hi - issue with single speed / track bike headset / chain.

So, when braking, and then pulling back on the handle bars, theres a "knocking" sound - almost as though the headset / stem is is moving slightly! (threaded). There's also a lot of vibration through the headset and forks when braking, which would make me think the headset is loose...?

However, there's no play anywhere in this area, its pretty solid, all fixings are well tightened and generally feels like a lovely bit of assembly work on my part

I feels almost like it could be a result of the chain engaging when under force, but then haven't had this on any other bike so I'm lost here!

Help / thoughts would be appreciated !!!

sungod

if you straddle the bike, hold the front brake full on, then shove hard forwards/backwards on the bars can you feel any slight knocking as you do it? if you can then i'd say the headset needs adjusting to take out slack, it only needs a tiny amount to be noticeable

Monty Dog

Sounds like poorly adjusted headset - check that the top cap isn't bottoming-out on the steerer/expander. Fit a spacer above the stem and try re-tightening.

Pushiron Jud

Thanks for the replies - when straddling the bike and holding the brake lever hard there is no knocking or loose feeling.

When doing this and pressing down on the peddle and putting force through the chain the knocking back and forwards begins

Sounds like I need to rebuild the head set to be sure!

sungod

do you get the knocking if you lock the front brakes and manually shove the bars back/forth?

if not, then it's probably not the headset - you can put more force through it with the shoving than you ever could with the pedals

if it's only when force is applied via pedals then it's something else