Using a threaded fork with a threadless headset / stem.. should i fill threads?
 

I've got about 2cm of unthreaded steerer tube under the stem, which is about 2/3 of my stem and well above the lower bolt. I figure it should be safe for street riding.. is this a good assessment?

Also do I need to fill the threads on the top part that is under the stem? I've seen people mentioning JB Weld when I did searches on this topic. Is it just to prevent marring of the stem?

http://i.imgur.com/xplsLy7.jpg

Hmm. I'd saw off the excess.

Yeah I will do that before any thread filling.. no point in filling threads that will be cut off :lol:

why not use a treaded headset ? which would look & work better for the bike . If the steering post is still too long then cut it .

if you don't want to get a threaded headset and a quill stem, and are willing to take any chance that arrangement may present, and i don't think there is much, i would just throw a couple of spacers over the threads on top, if you didn't want to cut it, and call it good.

and, yes Martha, that's a ghetto setup if ever there was one. :lol: nice to see someone that's not too picky.

Is the steerer tube steel? If so you should be fine, I have a couple franken-bikes setup this way. You just need to make sure the bottom half (at least, more is better) of the stem is clamping on the unthreaded section. Classic case where the steerer tube is too long to run threaded, but too short for a "proper" threadless setup.

I have never bothered to fill in the threads. But keep in mind they will probably get a little bunged up clamping the stem around them.

i suppose i could do that, though then i'd need to get a 1-1/8" quill stem. being able to switch to a threaded headset might be a good reason not to fill the threads though

There are threadless adapters you can use instead of a quill stem:

http://media.nashbar.com/images/nash...-NCL-ANGLE.jpg

Nashbar Stem Adaptor

yeah steerer is steel. as you mention, fork is "in between" sizes... lightweight steel forks for 26" wheels are tough to come by, so i'm making due with what I've been able to find.

Glad to hear that i can get away without filling the threads; i don't mind some marks on the inside of the stem.

I wouldn't bother filling the threads, and I doubt that there would be much marking on the stem unless you tightened the clamp bolts excessively tight; there is still a fairly large surface area to distribute the force. And please grease the bolt threads, one already looks rusted. Might want to spend the pennies for stainless fasteners; you should still grease them.

that "rust" is actually grease. brand new (old stock) stem

I don't see a star nut setup? how are you tensioning the fork? I am more of a stem guy, but what i know of threadless is you need the starnut to hold the fork on, and the stem is just to attach the handle bar.

i haven't installed the star nut yet. the pic was just to show how much of the unthreaded fork under the stem :) I think I will trim the steerer down before I install the star nut

a split internally threaded sleeve with the OD of 9/8" will both fill the cut thread, reinforce, and make the Outside diameter compatible with current stems..


BBB BHP 20 is a quill with a center wedge and its top hex internally threaded for (threadless preload)
often used as a stem raiser , it can go 100% within the steerer , its whole length.

reducing the possibility the fork will fail at the threads cut thin, but not supported inside by the Quill stem.

OP's steerer tube is already 1 1/8" threaded.

BBB BHP 21 is what I got for my threadless stem raiser . I'm too old for a Down on all 4's aero Tuck..

cutting threads weaken tube section than before cut remains a fact, its only a 1/16th wall tube & half that where cut.