patriotbmx

Ive been riding bmx for a while, and I remember when we used 1 inch headsets, but I dont remember how to work on one. I got a fixed gear from ebay and Im having a few issues getting it running right. Any help would be appreciated.

1. The headset feels tight but the bars and forks are still move independently of each other. Ive tightened the stem down as much as it will go and still nothing. What am I doing wrong here?

2. Now and then while pedaling the rear cog skips, like its not engaging. I tightened the little slotted ring right in front of the cog but it didnt help. It would seem, from whats happening, that the cog is moving. How can I tighten this up?

Landgolier

Dude, I don't want to bare anything with you, but here you go:

1. 1" threaded or threadless? I'm assuming threaded. The headset doesn't hold the bars in, you gotta tighten the bolt on top of the stem for that. You have probably overtightened the headset by this point, as well. Get on the park tool site and learn how to properly adjust it.

2. The slotted ring is your lockring, it's threaded opposite of your cog (it's left hand thread). You have to tighten your cog first and then your lockring. This takes a chain whip and some kind of lock ring hook or tool. You can get around using the chainwhip using the rotafix trick (google for rotafix), but be sure to put a rag around the chain at the bottom bracket so you don't scar it. You also don't need it crazy hero tight since you have a lock ring.

I'm guessing you might have chain tension issues as well, since you're new to fixed gear. This could be causing the "skipping," especially on a new drive train.

patriotbmx

Thanks for the help. Chain tension isnt an issue and the line is good. Probably just a loose cog.

As for the front end, it is threaded. The headset isnt overtightened. So if tightening the stem bolt isnt working, do I have a bad stem? I have it almost all the way in the steer tube.

Landgolier

OK, I misread, you said that the headset felt tight, and then I thought you said you had tightened it down as far as it would go. My bad. Take your stem out and see what's up down there. Loosen the bolt about 3 turns, give it a tap with something heavy, and pull the whole rig out. It's a pretty simple opposing wedge assembly, if you don't know how it works now it will make immediate sense when you see it. It's pretty easy to tell if something is broken. Clean the rust off and lube it before you put it back in, especially the diagonal surfaces that need to move against each other. Those surfaces tend to get corroded since it's usually an Al stem and a steel wedge. You might also want to do a flashlight inspection of the inside of the steerer tube while you have the stem out, though issues in there would be pretty weird.

Landgolier

Also, since this is an ebay rig, it could be a suicide hub. If the lockring comes off when you turn it counterclockwise, post up again here and we'll get you out of that mess.

Francis Buxton

I was thinking the same thing.

While many people poop on those, I own 3 fixies, and only one has a true track hub (hey, I'm cheap, and no one makes a good off-road fixie hub).

My general method for setting a track cog is to get it tight with the whip and then put it on the bike (with no lock ring). Ride around the block, mashing down on the pedals as much as possible without any backpedaling. That should get it set good and tight. Then pull the wheel off and set your lockring with your hook spanner. ONE drop of BLUE loctite on the threads of the lockring will set it (and you'll still be able to get it of some day).

patriotbmx

Thanks again. It is a suzue flip flop hub so I dont think thats what would be considered a suicide hub.

The bike actually came unassembled and nothing looked wrong with the stem. No rust, corrosion, etc. The wedge seemed to move pretty freely. Thats why Im perplexed. Could something actually be wrong with the inside of the steer tube??? It would seem unlikely to me but the bike is semi-old.

DannoXYZ 

If you've got the stem out:

1. measure the OD of the quill on the stem and make sure that it's a TIGHT fit with the ID of the steerer-tube. There's several sizes of stem-quills... 0.833", 22.0mm, 22.2mm, etc. if they don't match exactly, there'll be some wobble that will make it hard for the stem to grip tightly.

2. Check the wedge and grease the sliding surface between it and the quill of the stem. Then tighten the bolt and make sure it pulls the wedge wider as it tightens. Sometimes overtightening a stem-bolt will strip the threads and you'll have a spot on the bolt where it won't pull on the wedge anymore; it just spins.

3. Then inspect your steerer tube to make sure that the expanding-wedge hasn't ballooned out the steerer. You can usually adjust the stem up or down from that expanded spot to grip a new "virgin" spot on the steerer. Also would be a good ideal to really clean up the insdie of the steerer with a rag and some solvent so that there's no grease on the walls.