Pinched stem

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1/25/2018 5:17 PM
Edited Date/Time: 2/4/2018 3:38 PM

I’ve looked it up in the search bar and saw an old thread saying just remove the bolts and put a quarter inbetween and just reverse thread it so the bolts push the quarter and unpinches the stem. Anything else ?

The stem is a Cult Salvation, it’s only a year and a half old .. any reason why it’s pinching ? I don’t adjust it much and hand tighten it only . Bending it back a tad won’t affect the clamping system all too much huh ?

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Instagram : braydenbuckingham
My Cult 2 Short

1/25/2018 5:31 PM

The coin spreader trick works very well but you don't want to be stuck with having to use it long-term. I'd say to replace the stem whenever you get the chance. It's only good for small movements though, bend aluminium back a little too much and it'll snap so only use this trick to get the stem on and off when you need to.

It doesn't take much more than the "ideal" tension to pinch it a little; if you take it off and put it on again a few times, tightening it just a little bit too much, it'll pinch little more every time.

Again, don't try bending it back, it'll make it far more likely to crack or snap or you could make it entirely unusable if the bending elongates and ovalises the hole.

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My Sunday Soundwave V3 Build
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1/25/2018 5:52 PM

My buddy’s done the coin spreader trick before and it’s worked, except when he used one of my dimes haha. use a nickel or a quarter.

Photo

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1/25/2018 9:04 PM

Stay away from pennies at all costs.

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1/25/2018 9:19 PM

I've broken 2 stems tightening them too much so definitely be careful with aluminum it can take as much as you think it can.Photo

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1/25/2018 10:25 PM

Hand tight without too much effort with a regular length allen key is enough. About 12nm at absolute most. But some stems just have a tendency to warp and pinch

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1/25/2018 11:30 PM

NateBrown62 wrote:

I've broken 2 stems tightening them too much so definitely be careful with aluminum it can take as much as you think it can.Photo

...more

That's crazy...

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1/26/2018 2:00 AM
Edited Date/Time: 1/26/2018 2:01 AM

My stem looks like the picture besides the crack . Really that bad huh ? I don’t want nor can I afford to replace it right now . This shit was almost 100$ with taxes yet along shipping ..

I’ll do the coin trick tomorrow and see if that helps , and if it’s still close to pinching I’ll run it anyways

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Instagram : braydenbuckingham
My Cult 2 Short

1/26/2018 2:02 AM

Atlantis has the make stems on for 60 bux dude. Well worth your money.

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1/26/2018 2:12 AM
Edited Date/Time: 2/4/2018 3:41 PM

Photo

Photo

so first picture is bolts loose , second they’re off ... can’t fit a quarter in fully . I can try and smash it in with a mallet but I think the coin will move and if not , it’d probably fuck up the stem ?

Also if it matters I switched bolts to hollow bolts and hand tightened them . I wouldn’t crank down to hard on hollow bolts .

Isn’t there some tool that acts like an expanding cylinder ? That would work .
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Instagram : braydenbuckingham
My Cult 2 Short

1/26/2018 2:31 AM
Edited Date/Time: 1/26/2018 2:33 AM

I have a question: if the stem is pinched shut on the steer tube doesn't that mean that the stem has been stretched and is ruined? Or can the stem "rebound" by being pried open? I've never seen aluminum return to it's unstretched state by being pried open. Or did the TS thighten the stem bolts when the stem was not on the steer tube and only needs to pry it open? I'm confused.

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1/26/2018 2:31 AM

I think they are called reamers for stretching

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1/26/2018 2:36 AM

Brayden_Buckingham wrote: Photo

Photo

so first picture is bolts loose , second they’re off ... can’t fit a quarter in fully . I can try and smash it in with a ...more

What you can do is file out the slot a little; it'll make it usable for long enough for you to replace it. You don't even want to attempt to bend it back, no matter what tool you try it with. If the stem survives the bending back, it'll be in a very weakened state and likely snap at the first hint of force.

The spreader trick won't work for that; it's only meant to be a momentary thing anyways, keeping the amount of displacement within the material's elastic range.

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My Sunday Soundwave V3 Build
Insta: @p.gibbons

"You can't educate pork"
- grumpySteve

"Life should not be a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside in a cloud of smoke, thoroughly used up, totally worn out, and loudly proclaiming "Wow! What a Ride!""
- Hunter S. Thompson

1/26/2018 2:39 AM

Rubio151 wrote:

I have a question: if the stem is pinched shut on the steer tube doesn't that mean that the stem has been stretched and is ...more

It's ruined, bending it back will weaken it further, possibly crack/snap it and overall just make it worse.

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My Sunday Soundwave V3 Build
Insta: @p.gibbons

"You can't educate pork"
- grumpySteve

"Life should not be a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside in a cloud of smoke, thoroughly used up, totally worn out, and loudly proclaiming "Wow! What a Ride!""
- Hunter S. Thompson

1/26/2018 2:42 AM

BcBMX80 wrote:

I think they are called reamers for stretching

Wouldn't work, the ID of the clamp is probably pretty close to what it needs to be, the clamp overall has stretched around the steerer tube, i.e. if you straightened it out, it'd measure a few millimeters longer than what it should.

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My Sunday Soundwave V3 Build
Insta: @p.gibbons

"You can't educate pork"
- grumpySteve

"Life should not be a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside in a cloud of smoke, thoroughly used up, totally worn out, and loudly proclaiming "Wow! What a Ride!""
- Hunter S. Thompson

1/26/2018 4:20 AM
Edited Date/Time: 1/26/2018 4:34 AM

I just want to point out that, when a stem pinches, usually it is from the material "stretching." In other words, the steerer hole has remained 1 1/8" but the aluminum has stretched a bit, letting the clamp pinch.

If it is stretched & slides on and off the steerer fine while pinched, then the coin method will do you no good. This will just widen the hole, and it will go back to being pinched as soon as you tighten it down enough to clamp the steerer properly. & as others mentioned, you'll weaken your stem this way.

My advice is to file/machine out a slightly wider slot and continue riding it. & i dont see any harm in running it this way, or at least it won't be any weaker than it is now. Only use the coin method if your steerer tube hole appears to be smaller than 1 1/8" now, & avoid over-doing it whatsoever.

Also, I rode a mostly-pinched SXTN for over a year. The Odyssey stems are renound for doing so & are still considered some of the best on the market. So, I wouldn't consider your stem ruined until you ruin it (by trying to spread the hole wider, and then smaller once again when you tighten it back.) If you can get away with just filing out a larger slot, it should be structurally sound still. Just keep an eye on it to make sure it doesn't pinch further.
If you have to file it out a second time, I'd say it's ready to see a trash can.

Also also, I've found that all stems pinch a little bit. It's perfectly normal for most stems. Some companies just don't account for it and use really narrow slots in the clamp, so when it pinches a normal amount, the stem can't clamp properly. Chances are, if you had a stem with a wider slot, you would have never even noticed that it stretched a bit.

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1/26/2018 4:31 AM

The only issue with widening the gap is that the material will continue to stretch before its as tight as it should be. So it'll weaken it, and possibly crack whilst you're tightening it. If you've over tightened the bolts once, the damage is already done. The coin trick won't work because the material is already stretched. New stem is the only option imo, and don't over tighten it.


And a reamer is what's used to remove material to make a hole/tube a uniform internal circumference (often used to remove paint or blemishes in seat tubes etc)

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1/26/2018 9:12 AM

Don't try to use that thing off anything crazy. The point of the stem is for the metal NOT to touch. You can easily find a stem for cheap at Albes or Empire/etc.

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