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  #1  
Old 11-06-2024, 10:28 AM
mass_biker mass_biker is offline
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2 bolt threadless stem?

Saw that Thomson is now offering a new “G2” (gravel?) threadless stem…an update of their X2 stem. I have been on the lookout for a 2 bolt threadless stem that would make break down/build up of my Ritchey Breakaway that much easier, but have had little luck finding one. Any other options out there other than this $150+ new offering from Thomson?

Thanks
MB
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  #2  
Old 11-06-2024, 11:43 AM
Mark McM Mark McM is offline
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I've seen too many handlebars separate from the bike with 2 bolt stems to ever want to use a 2 bolt stem.

Unlike with single bolt stems (in which handlebar encircles the handlebar clamp and is pinched by the bolt) or 4 bolt stems, on a 2 bolt stem the handlebar will detach if one of the bolts breaks. I've seen multiple cases of this happening
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  #3  
Old 11-06-2024, 11:46 AM
Likes2ridefar Likes2ridefar is offline
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My 2 bolt Thomson slippped holding the bar, but it was not this new gravel version. I’m all for saving time and always looking for efficiency gains but two bolts on a stem isn’t one of them…a ratchet makes short work of this.
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  #4  
Old 11-06-2024, 12:03 PM
d_douglas d_douglas is offline
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I rarely break bike parts, but the original X2 was one of them. I didnt get hurt, but man, it spooked me to hear a faceplate crack while riding.

In spite of me thinking these are beautiful looking stems, I would never ride a two-bolt Thomson again, redesign or not!
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  #5  
Old 11-06-2024, 12:13 PM
slambers3 slambers3 is online now
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Pro vibe stem with the puzzle faceplate is two bolt- I’ve used them a bit and never had issues with this design.
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  #6  
Old 11-06-2024, 12:31 PM
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donevwil donevwil is online now
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The only 2 bolt faceplate threadless I've liked was the 3T Forgie (2x M5 faceplate and 1x M6 @ steerer). Granted the aesthetics are a bit dated, but they can be had for cheap.
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  #7  
Old 11-06-2024, 12:33 PM
mass_biker mass_biker is offline
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Great suggestions

Think I’ll see if I can snag one of those puzzle type stems
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  #8  
Old 11-06-2024, 05:40 PM
Fat Cat Fat Cat is offline
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I rode a Weyless two-bolt on a MTB for years and never had a problem. I also have Profile Design two-bolt quill stems on a couple road bikes that were fine.
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  #9  
Old 11-07-2024, 12:14 AM
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Old School Old School is offline
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I forgot about the puzzle stems. That's a genius recommendation.
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  #10  
Old 11-07-2024, 05:14 AM
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saab2000 saab2000 is online now
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I have had Thomson stems in the past and I had bar slippage. And with the history of broken stems I would simply look elsewhere. This is a case where 4 is better than 2.
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  #11  
Old 11-07-2024, 11:23 AM
tellyho tellyho is offline
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I have a 2 bolt older Bontrager that works great and has been problem-free. I have seen a broken 2 bolt Thomson, though the break did not relate to the 2-bolts....
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  #12  
Old 11-07-2024, 11:30 AM
benb benb is offline
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Quote:
Originally Posted by Mark McM View Post
I've seen too many handlebars separate from the bike with 2 bolt stems to ever want to use a 2 bolt stem.

Unlike with single bolt stems (in which handlebar encircles the handlebar clamp and is pinched by the bolt) or 4 bolt stems, on a 2 bolt stem the handlebar will detach if one of the bolts breaks. I've seen multiple cases of this happening
On top of all this we have so many members on this forum who have had the face plate break on Thomson 2-bolt stems.

There is basically no forgiveness on this for me. It's just WAY too dangerous. I got so lucky mine broke on the trainer.

So it basically boils down to.

- 2 bolt stems are inherently more dangerous than 1 or 4
- Thomson has a history of failures
- There is no ultra compelling reason or benefit to using a Thomson stem anyway, they are not ultra light, ultra strong, etc.. in comparison to other companies

Who the heck cares if it is 5-10g heavier, make the thing not break.

I have had plenty of 2-bolt stems that were beefy and were fine but IIRC all my bikes and my wife's and son's all have 4-bolt stems now, they all came that way.

I also still can't believe after all that Thomson went with smaller/more fragile bolts on their 4-bolt stems than 99% of all other stem manufacturers. What was the point?

Last edited by benb; 11-07-2024 at 11:33 AM.
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  #13  
Old 11-07-2024, 01:12 PM
Peter P. Peter P. is offline
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I've had a Ritchey Comp two-bolt faceplate stem on my mountain bike for decades without a problem. But Tom knows how to design stems...
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  #14  
Old 11-07-2024, 02:31 PM
fredd fredd is offline
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Quote:
Originally Posted by slambers3 View Post
Pro vibe stem with the puzzle faceplate is two bolt- I’ve used them a bit and never had issues with this design.
This is the correct answer
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  #15  
Old 11-07-2024, 03:42 PM
hokoman hokoman is offline
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Quote:
Originally Posted by benb View Post
I also still can't believe after all that Thomson went with smaller/more fragile bolts on their 4-bolt stems than 99% of all other stem manufacturers. What was the point?
Reduce the possibility of over tightening if you're not using a torque wrench? The smaller torx/allen wrenches flex as you tighten. That's my guess.

To the OP, I would consider getting a locking headset spacer and leaving the stem with your bars on your Breakaway.
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