Bicycle Mechanics - Quill stem won't go all the way down

Hey, I was previously using a 1" to 1 1/8 adapter and I recently bought a new 1" quill and liking it so far but how come it doesn't go all the way down in the steering tube? The bike frame I got is a kilo tt bike frame and fork from bikeisland.com If you're not sure, I will provide pictures if needed.

Good quality steerer tubes are butted (thicker wall at the bottom, where the greatest stress is). Maybe the stem reaches the butted area before it can be fully inserted. Is this a smaller frame with a relatively short head tube?

Hmm.. well it is a 47cm frame and it's possible that the wall is thicker at the bottom because it stops at a certain point. I'm thinking of cutting 1-2" off so that it can be lowered, I saw someone did in this forum so I think will will try that.

Good quality steerer tubes are butted (thicker wall at the bottom, where the greatest stress is). Maybe the stem reaches the butted area before it can be fully inserted. Is this a smaller frame with a relatively short head tube?

ludwig: If, as oldyellr says, the steerer does taper down in inside diameter, be very careful NOT to lock the quill wedge into the tapered section. It could come loose without warning possibly resulting in loss of control. Having the handlebars come loose in your hands is only funny in cartoons. Also be sure to observe the minimum insertion depth.

Hmm.. well it is a 47cm frame and it's possible that the wall is thicker at the bottom because it stops at a certain point. I'm thinking of cutting 1-2" off so that it can be lowered, I saw someone did in this forum so I think will will try that.Yes, 47cm is definitely a small frame and just looking at your last pictures, the stem has to be hitting the butted portion of the steerer, or even the brake bolt. You could cut the stem shorter on the same angle provided the bolt has long enough threads or you can find a shorter bolt.

This is tricky business!

On the smaller frames, there is no stem that I know of that's properly designed for the short engagement, but one should know that an overly-inserted quill stem is also extremely dangerous!

I bought a garage-sale Schwinn Circuit this past Summer and it was a sub-50cm frame with the original Cinelli bars and stem.
The stem had been inserted forcefully, such that the expander was slightly into the tapered lower end of the steerer.
The bolt was very tight and the limit line was well above the top nut of the headset.
I test-rode the bike with the stem that way and as I was accelerating out of the saddle across an intersection the stem instantly became completely loose as the expander pulled free of the internal butted taper. The bike suddenly veered to the right sharply as I returned to the seated position and (luckily) applied some weight to the bars. A quick dab of my left foot saved me from a hard crash, and at first I thought the front wheel had come out of the dropouts, a theory that was immediately dispelled by the lack of any noise or any collapse of the front end. In fact the quill never came out of the steerer (I think the front brake cable was too short to allow that).

I can't believe these small frames are sold without properly-fitting stems. Like I said, the stem won't even go in to within 1/2" of the limit line! This is the greatest argument for threadless steerers imho.

If you cut the stem, the cut-off end will have thicker walls than the original end. If the stem has a round, internal wedge as opposed to a slash-cut wedge, the thicker walls would be much more likely to crack from the expanding flex.
If the stem has the slash-cut end and wedge then the expanding portion may still end up within the threaded and slotted portion of the steerer, not the strongest!

This is tricky business!


If you cut the stem, the cut-off end will have thicker walls than the original end. If the stem has a round, internal wedge as opposed to a slash-cut wedge, the thicker walls would be much more likely to crack from the expanding flex.


Absolutely. The internal stem is tapper reammed. The cut piece is the total length of the tapper.

Tom

where is the top nut on the headset?

If you are more interested in safety than style, you should either get a quill with a shorter insert section, or go back to the adapter and threadless stem.

If you are more interested in safety than style, you should either get a quill with a shorter insert section, or go back to the adapter and threadless stem.

With the adapter, doesn't it also have the usual min-insert line the same ~2" from the end?
So, is it any better?
Also, I've never seen a quill stem with a "shorter insert section", that was my issue with these sub-50cm frames using threaded steer tubes---very dangerous imo.


"where is the top nut on the headset?"

I think that view is a close-up, showing only the top and inside of the adapter quill.
That's not the internal butted steerer taper we were talking about at all.