My otherwise bulletproof road bike has developed a strange popping noise when turning the handlebars back and forth. What is this sound? Beats the hell out of me, but here's how I fixed it.
1. Pull handlebars and stem off - I hung them from a bungee cord from the frame and avoided unhooking them entirely and having to redo my cables. Here is a shot of the top bearings:
These are drop in sealed bearings that don't need much maintenance.
2. Remove bearings - take the bearings out of the cups. They aren'y pressed in or anything, so they come out easily.
3. Clean the bearing cups - wipe all the grease and dirt form this area. I reached pretty far into the frame to be sure I got it all. Also a good chance to inspect the inside for any nicks or dings.
4. Grease the cups - apply grease to the surface the bearings sit on. I used the amount shown.
There is a beveled surface on the bearing where it rests on the frame. This is where you want to apply grease. I didn't apply a ton of grease as it can damage the carbon, only where the bearing will sit. This is the surface I'm talking about:
5. Clean off the lower race - the lower race was also dirty, so I cleaned and greased that as well. Same thing, I tried not to get and grease on the carbon cork or steer tube.
6. Clean bearings - the bearings are sealed, so you don't need to grease them, and you REALLY don't want to de-grease them (with WD-40 or anything). Simply wipe them down thoroughly and inspect for any damage. These are pretty tough bearings and can handle a lot of abuse.
7. Drop the bearings back in - reassembly is the reverse of disassembly. Since it's an aluminum stem and a carbon steerer, it's important to not over tighten the bolts. You can see where the stem calls for 8-10nM on the tightening bolts. I set my torque wrench to 9 and it feels solid. It's good practice to tighten each bolt a bit so the stem clamps uniformly.
Got it all back together and the popping noise was gone. Ready for another summer of riding!
1. Pull handlebars and stem off - I hung them from a bungee cord from the frame and avoided unhooking them entirely and having to redo my cables. Here is a shot of the top bearings:
Top bearings and upper race
These are drop in sealed bearings that don't need much maintenance.
2. Remove bearings - take the bearings out of the cups. They aren'y pressed in or anything, so they come out easily.
Exposed bearing cups
3. Clean the bearing cups - wipe all the grease and dirt form this area. I reached pretty far into the frame to be sure I got it all. Also a good chance to inspect the inside for any nicks or dings.
Cleaning cups
4. Grease the cups - apply grease to the surface the bearings sit on. I used the amount shown.
There is a beveled surface on the bearing where it rests on the frame. This is where you want to apply grease. I didn't apply a ton of grease as it can damage the carbon, only where the bearing will sit. This is the surface I'm talking about:
Contact surface
Dirty!
Clean!
6. Clean bearings - the bearings are sealed, so you don't need to grease them, and you REALLY don't want to de-grease them (with WD-40 or anything). Simply wipe them down thoroughly and inspect for any damage. These are pretty tough bearings and can handle a lot of abuse.
7. Drop the bearings back in - reassembly is the reverse of disassembly. Since it's an aluminum stem and a carbon steerer, it's important to not over tighten the bolts. You can see where the stem calls for 8-10nM on the tightening bolts. I set my torque wrench to 9 and it feels solid. It's good practice to tighten each bolt a bit so the stem clamps uniformly.
Torque wrench next to stem
Got it all back together and the popping noise was gone. Ready for another summer of riding!
No comments:
Post a Comment