Help me catch the Gremlins!

[440MTB]

Hi there all,

Trust you're well on this lovely Friday afternoon!

So I purchased a 2019 Scott Spark 910 from a well known seller here on BikeHub, and I've been having some challenges with the bike, I thought I'd get some input from you guys.

When I just got the bike, there was a tiny bit of play on the headset/steerer tube (when you rock the bike back and forth with front brake pulled, you could feel some movement on the top side of the frame). - I then took it to a LBS to take a look and they replaced the bottom bearing which apparently wasn't the right bearing and it was fine for a while.

I then noticed, as of late, there is a big "CLACK/CRACK!" from the headset under sharp heavy braking, and again the same loud "CLACK/CRACK" when I pull up on the bars (like doing a wheelie or bunny hop), and the front wheel hits the road.

I then took apart the entire steerer assembly and cleaned up all the grease, inspected everything (which seems okay to my novice bike mechanic eye), and regreased everything and reassembled, but alas, the issue persists.

I was then told by another mechanic that I may have to remove the crown race which sits right against the crown and squirt a bit of WD-40 into the steerer tube as he's seen this on quite a few FOX forks in the past (I actually found this article on Pinbike as well: https://www.pinkbike.com/news/pinkbike-poll-has-your-crown-ever-creaked.html)

So today, when I get some time I'll take everything apart again and remove the crown race, and spray some WD-40 and see if it sorts the issue, but I'm not sure this is the issue.

I found some other articles stating it's got to do with the cable ferrules binding and snapping in and out of place (but I find this hard to believe, albeit I want to redo the all the cabling on the bike at some stage anyway).

Any advice/feedback/input on above would be GREATLY appreciated!

Other than that, I've given the old gal some TLC (cleaned and lubed the BB/Crank Spline, removed the rear triangle and rear shock to give all pivots and pivot bearings some TLC, new chainring, etc), and she's been a blast to ride on my local trails, especially when pointing her down some of the gnarlier stuff.

Have a great day further!

Edited December 2, 2022 by MandM

[SoloCyclist]

What does the "well known" seller have to do with this ?

Seems a bit irrelevant to the post.........

Edited December 2, 2022 by SoloCyclist

[Dappere]

@MandM I can only speak from my own experience.

"...there was a tiny bit of play on the headset/steerer tube."
This could be worn bearings, or as you mentioned was the wrong bearing(s). 

The "Clack/Crack" sound. Likely the bike just needs a headset service. If you feel you are a Novice Mechanic, rather let an experienced mechanic do the first service. 

[Barry]

Maybe not related to your problem at all but check the  rotor bolts see if they are tight and also the caliper.  Had an issue on a bike that felt like loose headset but turned out to be loose rotor bolts.

Edited December 2, 2022 by Barry

[Dappere]

5 minutes ago, SoloCyclist said:

What does the "well known" seller have to do with this ?

Seems a bit irrelevant to the post.........

From that whole post, that is the only thing that stood out to you 🤯. 

OP was giving context on to the purchase of the bike. 

[440MTB]

23 minutes ago, SoloCyclist said:

What does the "well known" seller have to do with this ?

Seems a bit irrelevant to the post.........

Uhm... Merely stating where I got the bike from my guy... Your post seems a lot more irrelevant to the topic than me merely mentioning that I purchased it from a well know Hubber... The ideology behind me mentioning it's from a well know hubber, is that it's not bought from gumtree in an unknown condition, etc. I.e. bought from someone who does service the bike before hand and gives some form of mechanical warranty, etc.

17 minutes ago, Dappere said:

@MandM I can only speak from my own experience.

"...there was a tiny bit of play on the headset/steerer tube."
This could be worn bearings, or as you mentioned was the wrong bearing(s). 

The "Clack/Crack" sound. Likely the bike just needs a headset service. If you feel you are a Novice Mechanic, rather let an experienced mechanic do the first service. 

Hi there, thanks for the input. The first service was done at an experienced mechanic, but I need to learn how to work on my bike myself hence I took the headset apart to take a look - Going to my LBS tomorrow with the bike for an experienced mechanic to take a look and make a recommendation.

15 minutes ago, Barry said:

Maybe not related to your problem at all but check the  rotor bolts see if they are tight and also the caliper.  Had an issue on i bike that felt like loose headset but turned out to be loos rotor bolts.

Howdy! Thank you for your response. I've already checked the rotor and caliper bolts and torqued them to spec, the sound can also be recreated when bouncing the bike on the rear wheel when fully vertical, so definitely something to do with the headset/fork.

Edited December 2, 2022 by MandM

[Barry]

Have you had the pivot bearings looked at? Maybe the bushing on the rear shock. Sound and vibration can travel throgh a frame and what might sound like BB could be seatpost and so.

[love2fly]

Have you checked the top bearing ie correct bearing & still ok? Theres a small chance it WAS the correct bearing and its now incorrect?When you reassemble the steerer are you first tightening the centre cap bolt and THEN the 2 pinch bolts on the stem? Do you have the right amount of spacers on the steerer?

[440MTB]

2 minutes ago, Barry said:

Have you had the pivot bearings looked at? Maybe the bushing on the rear shock. Sound and vibration can travel throgh a frame and what might sound like BB could be seatpost and so.

I've pulled apart the rear this week and just serviced the bearings (removed dust covers/shields, cleaned/degreased, and repacked them with fresh grease), the rear is smooth as butter now and there aren't any creaks/cracks from the rear.

I am planning on replacing all the bearings next year though.

The "CRACK!" sound happens when I break hard on the front, like doing a stoppie, and again when the fork goes in the other direction when doing a wheelie/bunnyhop pull on the bars and the front wheel hits the ground, so I'm 99% sure it's got something to do with the headset/fork, but I'll ask my mechanic at my LBS to take a look/listen tomorrow as well just to make sure.

[440MTB]

7 minutes ago, love2fly said:

Have you checked the top bearing ie correct bearing & still ok? Theres a small chance it WAS the correct bearing and its now incorrect?When you reassemble the steerer are you first tightening the centre cap bolt and THEN the 2 pinch bolts on the stem? Do you have the right amount of spacers on the steerer?

Hi there man! Thanks for the reply - I've tried checking online what the correct bearings are for my bike, but unfortunately I can't get much info and the bearings seem to fit correctly, there is a spacer for the top bearing that fits snug on the steerer tube and two steel washers, the fit seems fine, but I'll ask my mechanic to take a look tomorrow to confirm.

As for tightening the headset, I do tighten the center cap bolt first until there it compresses everything nicely but still moves freely, then only do tighten the pinch bolts and torque to spec.

I must say, Scott's support for documentation is terrible, I can't find any technical diagrams for my bike on their confusing and over complicated support portal.

Edited December 2, 2022 by MandM

[love2fly]

Might even be a creaky fork tube. If you're in Joburg Jako at Shockingly Good Service (specialist suspension guy) can help. 0714398832

[440MTB]

1 minute ago, love2fly said:

Might even be a creaky fork tube. If you're in Joburg Jako at Shockingly Good Service (specialist suspension guy) can help. 0714398832

Thanks for the recommendation man, but I'm in Cape Town - But there are some good suspension guys around here, will check what my mechanic and I can figure out and make a call.

Edited December 2, 2022 by MandM

[HowardSteele]

Hi there pulling the btakes and rocking the bike will always give the impression that there is play in the fork ,turn the bike upside down or clamp in stand and then move the fork lowers back and forth.

[Wannabe]

Any good LBS will have a manual with all the headset bearings for the different bikes and models. If not a "hard copy", they should have a web page they consult.

Syncros is the OEM supplier for Scott. Maybe you can scratch around on their website.

I know I had quite a hard time to get the correct headset bearings for my 2016 Spark frame when I did a rebuild. Luckily my LBS got me sorted out.

As stated, there will always be some flex in the forks (seen as forward/rearward movement) but there never should be upward movement with the headset in the frame, nor should there be crack/clack sounds.

[Wyatt Earp]

45 minutes ago, MandM said:

I've pulled apart the rear this week and just serviced the bearings (removed dust covers/shields, cleaned/degreased, and repacked them with fresh grease), the rear is smooth as butter now and there aren't any creaks/cracks from the rear.

I am planning on replacing all the bearings next year though.

The "CRACK!" sound happens when I break hard on the front, like doing a stoppie, and again when the fork goes in the other direction when doing a wheelie/bunnyhop pull on the bars and the front wheel hits the ground, so I'm 99% sure it's got something to do with the headset/fork, but I'll ask my mechanic at my LBS to take a look/listen tomorrow as well just to make sure.

Contrary to popular belief, removing seals, cleaning bearings and greasing them is hardly ever successful.

The balls pit as well as the race they run on.

[Long Wheel Base]

9 minutes ago, Wyatt Earp said:

Contrary to popular belief, removing seals, cleaning bearings and greasing them is hardly ever successful.

The balls pit as well as the race they run on.

Off topic, I know I have been scarce here this year, but when did you get back? Welcome back!!!