#1
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Ideal placement of expander with a quill stem
Hi all I’d like to mine the forums brains please ,I’ve a bike to pick up that I know is going to be too short in the headtube [and top tube] ,iam planning the partial rebuild around one of the Nitto extra long stems [new],where is the ideal location within the headtube for the expander please ? Never had to think about this before as all my bikes have been an ok fit and used normal quill stems ,thanks in advance ,Stef
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#2
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Just don’t have it higher than the minimum insertion line.
It’s a steel fork, right? Beyond having too little stem inside the fork, I don’t think it matters. |
#3
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It goes at the right height for your position. Just don't overtighten. Having said that, you want the wedge to be inside the head tube.
I collect dead bike frames to make stuff out of. I have a couple of forks where people over-tightened the wedge and split the steerer. It really doesn't need to be that tight. If the fork has a slot for a toothed washer, that's a real weak spot on a threaded steerer. |
#4
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Thanks folks but I was thinking more along the lines that since these Nitto stems are so long vertically [19 and I think 22cm options],i’ve got the option to place the expander in best place to combat what will definitely be more leverage than a normal quill stem
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#5
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You don't understand how a quill stem works?
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#6
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Yes ,but I was assuming with regard to stiffening up things maybe it’s better to have the expander as low in steerer tube as possible and these Nittos give me that option due to their extra length
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#7
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Expander wedge toward the front of the bike, well below the threads or the fork because the steerer tube is weaker there.
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#8
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Some steerers are butted and you can only insert the quill stem so far down. With a long quill you might not be able to get the bars *low* enough.
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#9
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Thanks all ,I’ll know more when I get the bike it seems v well put together but bottom end tubing maybe not even Columbus or Reynolds [original finish but no tubing decals but wrapover seatstays and Campag ends ],I was also thinking about butted steerer but I really doubt it .My original thought in starting the thread was having as much distance between expander at bottom of steerer and where stem comes out at the top as on top of the tall height I might be looking at one of the longer lengths[horizontal]they offer
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#10
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Fit is more important than stiffness. I don't know about anyone else, but there is a fairly small range of handlebar height where my fit is proper.
I assume if you were worried about stiffness, you would have a different setup. One of those tall Nittos is not going to be stiff under any definition I am familiar with. |
#11
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Basically that's it. Doing so will keep the wedge below the threads. You don't want the expander wedge in the steerer threads. There can also be a butted section on the lower part of the steerer tube. You don't want the wedge in there either.
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#12
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Bing, bing, bing, we have a winner!
__________________
Chisholm's Custom Wheels Qui Si Parla Campagnolo |
#13
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'Nuther thing to think about - The joint between the top of the wedge and the rest of the quill is theoretically weaker than the solid portion of the quill ('cause you're levering the threaded rod there - yes the whole shibang flexes a hair). The wedge holds the quill in place, and the solid quill portion provides the real strength. Rules O the road say:
1. Put the weaker portion of the quill (that would be the joint I'm quacking about) 1.5 times the diameter of your headtube below any head tube weak areas. That would be 1.5" below the bottom of the threads (if using a 1" steerer tube), and in most cases, also at least 1.5" below the top of the headtube, in case you run a bunch of spacers. 2. Lube the quill and quill threads - I use a sticky grease - helps to not stick it due to rust. 3. Don't tighten too much, as has been mentioned. |
#14
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Thanks to all
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