photonick

I used to tool on my flatland bike back in high school heavily and was really good at working on it, but am just starting to work on my road bike. I currently am running 4 spacers below my stem and would like to lower the stem (guessing i have to take those spacers and put them on top of the stem. I have the tools required I'm just curious how difficult this is and if there is anything i should know before doing this.

Psydotek

If it's a threadless headset, all you need is a hex wrench. Loosen the stem, loosen the steering tube cap, and switch the parts around.

photonick

Its been about 5+ years since i worked on a headset its on a 2007 trek 1500 with a cane creek headset. I figured I just had to unscrew the bolt on top of the stem which im assuming compresses the headset like on my bmx bike and then loosen the stem bolts.

04jtb

Might seem obvious, but make sure you tighten the cap on top when you put everything back, otherwise it makes for an interesting ride.

photonick

So basically I'm assuming this is like the set up i had on my flatland bike back in the day the head set has a top and bottom bearing cup and their is a rod that goes through the head tube that clamps to the bottom of the fork and and the top of the stem and compresses, and this is what that cap on the stem is doing.

Also should i tighten that cap on top of my stem as tight as i can or what?

roadfix

When putting everything back together always preload the headset first by torquing the cap bolt before you tighten the stem pinch bolts. And don't overtighten that cap bolt......only slight tightening is all that's required to preload the headset.

markjenn

Actually, the cap bolt is used to preload the headset bearings, but once you tighten the stem pinch bolts, it is non-functional. You can loosen it, tighten it, or even remove it - it doesn't matter, although most just leave them as they had them before tightening the pinch bolts.

The cap bolt typically threads into a star nut or expander plug that "grabs" the inner surface of the steerer tube. What you're doing is pulling the cap down which pushes down on the stem, while pulling the fork up, thus preloading both the top and bottom bearings in the headset.

The cap bolt requires only light torque to preload the bearings. On my last build, the spec on a CK headset was something like 4-10 in-lbs which is practically nothing. I didn't have a torque wrench that goes this low, so I did it by feel. Like all bearings, you're basically just wanting to get the play out of assembly.

- Mark

photonick

Nice, i just unloaded the head set and pulled out the fork and kinda took a look around, nice sealed bearings i was surprised. Maybe I'm used to my old bike because i was nervous about the little gap between the fork and the frame and the upper headset cap that dirt would get through there, i had no idea they came with sealed bearings, sweeeet. Also is there any negative to putting all the caps on top and having the stem sitting right on the top headset cap.

roadfix

Sure, you can place the stem directly on top of the headset bearing and stack all the spacers on top for the time being. But depending on the stem I would insert a thin spacer just to be certain the stem is completely clear of the headset cup.

photonick

i have a pretty inclined stem its like 17 degrees so instead of moving the spacers i just flipped the stem which was about the same as moving 3 spacers and looks a lot more legit.

roadfix

I'm surprised no one suggested that to begin with, including myself. Good for you for flipping that stem!

photonick

Well my bike came with a 110 mm 7 degree bontrager select stem which was too long so my shop swapped it with a 90mm 17 degree bontrager select stem they had for free. It works length wise but it puts me in this really upright position, if this feels funky i might have to buy a 90mm 7 degree ish stem. Its nice to be able to flip the stem though between long rides and fast paced rides.

Camilo

Just wanted to re-quote this since it does a good job at showing how dead easy this is. Especially the part "Like all bearings, you're basically just wanting to get the play out of assembly." That's what the jargon "preload" means... a term I was unfamiliar with even though I'd been adjusting bicycle wheel bearings, etc. since I was a teenager. I didn't know it had a term "preload", I always thought it was just adjusting to get the play out of them without getting resistence

photonick

Everything went pretty well minus the fact that im OCD so lining everything up straight takes me way longer than everyone else. I probably need to tweak the angle of the hoods and some other stuff but i appreciate all the help.

photonick

Wow i just took it for a ride, what a different feel, the steering is a bit more twitchy but man really feels like a road bike now.