I just bought a 2nd hand salsa El Mariachi frame, that I will start to build this week. Unfortunately when I received it I realized that the previous owner probably has ridden it with the seatpost too high or inserted only a few cm and I noticed that the top of seat tube is deformed, have a look at the picture. Do you think it is safe to ride? or might break? suggestions? enter image description here thanks for your input

  • 2
    If the seatpost goes in to the correct depth it should be OK. The deformation appears to be around the slotted top only.
    – Carel
    Commented Jun 18, 2017 at 7:43
  • yes, deformation is actually not much and only around the slotted area. The previous owner was lucky that it did not break when riding. I will of course use it with correct insertion Commented Jun 18, 2017 at 7:47
  • 2
    I'd be a little conservative and use an overly long seatpost, if possible. Also, have a very good look for anything else that may be wrong on the bike, given the seller didn't mention it. To be fair, the PO may not have known.
    – Criggie
    Commented Jun 18, 2017 at 9:31
  • actually...I agree on several points: the seller is a little bit of a "lost" kind of guy...shipping has been a nightmare... I don't think he knew...and I am checking on all bike, and since the paint is in quite a sad state I am checking if I should send it back..or have it sandblasted, cleaned the rust (not much/just superficial), and have it repainted. But yes, I'll look for possible weaknesses and use an over long seatpost. Commented Jun 18, 2017 at 9:40
  • 1
    I would ride that without a worry. With a proper length post that section takes very little stress and would not result is a catastrophic failure. If it starts to split out then you just need to give up on the frame.
    – paparazzo
    Commented Jun 19, 2017 at 8:52

1 Answer 1


It's probably fine, especially if it's 4130 or something similar, as opposed to a heat treated and/or air hardening tube.

From one picture and without hands on it I wouldn't necessarily recommend this, but such damage on steel frames can often be more or less repaired by putting in a stout seatpost of the right size, wrapping the area in a rag, and going to work on it with a rubber mallet. One good reason to do this would be if the deformation was partially bulged inward and the seatpost wasn't moving very freely, or making bad contact and tending to slip.

It appears that there would be room to cut off the end and extend the slot, but since the deformed part in the picture isn't at the top anyway there probably isn't much point. If you were finding that a seatpost goes in rough because the whole top part of the seattube is bent backwards, then this could perhaps make sense. It's critical you preserve a long enough slot in order for it to be able to clamp. Framebuilders have a minimum slot length worked out; I've seen it mentioned but I can't find it right now.

  • yes, I am not sure either about how it is going to be and I think that a frame builder should see it in real life. I have a doubt that at the base of the cut area, where this kind ob deformation - bubble start, the steel is maybe splitting. not sure.... On the other hand the seat tube comes in without any problem. My doubt is that the frame will brake while travelling, since I bought it for touring off road. Commented Jun 19, 2017 at 5:47

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.