1" steel fork steerer tube tapered?
08-25-19, 04:24 PM
#1
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Thread Starter
1" steel fork steerer tube tapered?
Hi everyone, I'm finished building up my girlfriend's MBK Super Record, she loves it but there is a problem I noticed with the stem and steerer tube. You can see there is a noticeable gap between the stem and the headset lock nut (same issue with other stems I tried). I think the issue seems to be from the fact that this is a small frame, and that the fork steerer tube is tapered on the inside. All stems I tried cannot go any further down the steerer tube.
It feels like the steerer tube is tapered on the inside and I cannot engage the stem further down. For example, I cannot slam the stem. Please see the diagram of what I think is happing.
Any help with this?
My quick diagram of what I think is happening that does not let the stem engage fully with the steerer.
Notice the gap between with stem and the headset nut
Same issue here
It feels like the steerer tube is tapered on the inside and I cannot engage the stem further down. For example, I cannot slam the stem. Please see the diagram of what I think is happing.
Any help with this?
My quick diagram of what I think is happening that does not let the stem engage fully with the steerer.
Notice the gap between with stem and the headset nut
Same issue here
08-25-19, 05:08 PM
#2
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What happens if you remove the wedge nut from the stem, put it on the bolt, and slide that alone into the steerer tube?
If you remove the wheel and stem and look up into the crown, what do you see? Can you measure the bottom of the steerer?
If you remove the wheel and stem and look up into the crown, what do you see? Can you measure the bottom of the steerer?
08-25-19, 05:30 PM
#3
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Be cautious that you do not try to expand your stem wedge in a tapered portion of the steerer, it will not be secure. Having the bars come loose is only funny in the cartoons.
Read and heed!: https://www.sheldonbrown.com/handsup.html#danger
Read and heed!: https://www.sheldonbrown.com/handsup.html#danger
08-25-19, 06:41 PM
#4
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Thread Starter
I've removed the wedge nut and tried to slide only the stem in, it stops at the same area. I'll take a look with a flashlight later but the steerer tube does not look out of the ordinary.
08-25-19, 06:45 PM
#5
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Thread Starter
Be cautious that you do not try to expand your stem wedge in a tapered portion of the steerer, it will not be secure. Having the bars come loose is only funny in the cartoons.
Read and heed!: https://www.sheldonbrown.com/handsup.html#danger
Read and heed!: https://www.sheldonbrown.com/handsup.html#danger
What are some options for me here? Are there shorter stems or maybe a different type of wedge nut? I'm afraid that the stem only has about 1" of engagement with the steerer but extends up quite a bit.
08-25-19, 07:17 PM
#6
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I should have looked at Sheldon's website before hand, that's exactly the problem I am describing. Sheldon describes this as a problem with smaller bikes, and this frame is small, 49cm seat tube.
What are some options for me here? Are there shorter stems or maybe a different type of wedge nut? I'm afraid that the stem only has about 1" of engagement with the steerer but extends up quite a bit.
What are some options for me here? Are there shorter stems or maybe a different type of wedge nut? I'm afraid that the stem only has about 1" of engagement with the steerer but extends up quite a bit.
The stem in the pictures seems tall for the bike anyway. There are most definitely stems with shorter quills.
08-25-19, 07:55 PM
#7
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Good quality steer tubes are butted, and you won't be able to "slam" the stem into the butted portion at the base of the steer tube. Not, at least, without other serious problems down the road.
08-25-19, 08:46 PM
#8
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I've cut down a couple stems for smaller frames. You just need to do a decent job of matching the angle for the wedge. Also verify the stem wall thickness is fairly consistent.
