Knocking in fork

[gillyske]

Marz z1 2021 160mm
So I can feel and hear a knocking in my fork where the stanchions sit in the lowers.
Definitely not my headset or fork Axel.
Is this where the bushings are?
Is this a warranty thing or a service thing or is it normal. First time I've felt this in a fork.

 

[moorey]

Riding or stationary? I had a knocking feeling in my lyriks recently, only while riding, and only over small stuttery bumps. Concluded the damper needs a bleed, as its topping out with no damping in those first 10mm of travel.
Otherwise, yes, could be bushings or something else come loose.

 

[Flow-Rider]

Has it gone past the recommended service interval, otherwise warranty issue me says ? You shouldn't be hearing a distinctive knock on a fairly new fork.

 

[creaky]

Sounds like poor tolerance in a stanchion / bushing interface. Did you buy locally, or can you take to a marz agent for inspection?

 

[wkkie]

Coil or air?

 

[gillyske]

Stock air z1.
Came on the bike from 99 bikes. I'm not confident in their... anything. Hopefully they don't try troubleshoot it and just send it off to fox dealer, I hope it's not a big turn around time.

 

[gillyske]

Riding or stationary? I had a knocking feeling in my lyriks recently, only while riding, and only over small stuttery bumps. Concluded the damper needs a bleed, as its topping out with no damping in those first 10mm of travel.
Otherwise, yes, could be bushings or something else come loose.

Stationary, apply the front break and there is a bit of play back and forth, tightened the headset down and also torqued Axel properly, definitely not coming from either of those.

When I place my hand around the seal area that's where I feel the knock.

 

[leitch]

Stationary, apply the front break and there is a bit of play back and forth, tightened the headset down and also torqued Axel properly, definitely not coming from either of those.

When I place my hand around the seal area that's where I feel the knock.

How significant is it? Can also just be the stiction breakaway. I.e. fork is compressing slightly (~mm) under the weight shift. Wouldn’t be audible though.

 

[moorey]

Stationary, apply the front break and there is a bit of play back and forth, tightened the headset down and also torqued Axel properly, definitely not coming from either of those.

When I place my hand around the seal area that's where I feel the knock.

Do you need another stem spacer?

 

[gillyske]

How significant is it? Can also just be the stiction breakaway. I.e. fork is compressing slightly (~mm) under the weight shift. Wouldn’t be audible though.

I dunno, honestly it's just a noise/feel that only happens when I look for it. But if it's going to get worse might as well deal with it early into warranty.
Wish I could get thoughts from people who have a z1 or a 36 rhythm, feels like a fair bit of stiction off the top but I could be crazy.

 

[gillyske]

Do you need another stem spacer?

Will double check that, I don't think merida would duck it but who knows.

 

[link1896]

Drop the lowers.

Insert the stanchion into the lowers one at a time and rock around. Rock around with only the upper bushing engaged with the stanchion, then with both. This will help you identify bushing slop.

 

[creaky]

Drop the lowers.

Insert the stanchion into the lowers one at a time and rock around. Rock around with only the upper bushing engaged with the stanchion, then with both. This will help you identify bushing slop.

Personally, I wouldn’t be doing this when it’s a newish warranty issue. If the OP can feel the knocking / play holding around the wiper seal area and rocking back and forth then I’d be going to the shop or a Fox service agent.

Ive had that bushing tolerance issue previously and the lowers were replaced under warranty.

 

[gillyske]

Will gleefully go to the fuckwits thread but here's a video with the noise and me trying to point out where I can feel the knocking. And some pastey legs.

Edit: ignore the rattle of the ep8, the deeper knock is what I'm on about

 

[gillyske]

Drop the lowers.

Insert the stanchion into the lowers one at a time and rock around. Rock around with only the upper bushing engaged with the stanchion, then with both. This will help you identify bushing slop.

I'm too shit to do this.

 

[moorey]

Will gleefully go to the fuckwits thread but here's a video with the noise and me trying to point out where I can feel the knocking. And some pastey legs.

Edit: ignore the rattle of the ep8, the deeper knock is what I'm on about

Hold around the headset and do it again. Humour me.

 

[gillyske]

Hold around the headset and do it again. Humour me.

Issue still happening, headset area is solid. Mate had instilled the fear of ovalling head tubes when I first started riding.

 

[Mattyp]

loose brake rotor? brake pads moving in calliper? fork bushings? turn the bars 90degrees and rock back and forth and see if its still there. Hold the stanchion at the seal and see if you can feel movement between the 2 parts while you're doing it.

 

[gillyske]

loose brake rotor? brake pads moving in calliper? fork bushings? turn the bars 90degrees and rock back and forth and see if its still there. Hold the stanchion at the seal and see if you can feel movement between the 2 parts while you're doing it.

Not the brakes. will try the 90 degree thing tomorrow. Can't take it to a shop until lockdown is over anyway

 

[Petero]

Can't watch video right now but is it when the fork is topping out?