Couple of frame questions- 80s steel frames specifically
05-28-15, 07:02 AM
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Sunshine
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Couple of frame questions- 80s steel frames specifically
1- Why are there formed dents(crimps?) on chainstays? One chainstay has 2 dents and the other has only 1 dent. Why not the same on both chainstays?
2- What was/is the little protruding point of metal for that sticks out of the headtube on the opposite side of the headbadge? I am not referring to a 90degree bent piece of metal that a frame pump connects to. The point of metal I am asking about is on my 87 Miyata 912 and also on a couple of entry level 86/87 Nishiki bikes I picked up to recondition and donate. I mention this because its on both lower end and higher end frames. Its only a couple cm long(guess) and is between the top tube and down tube.
A couple of burning questions I have wondered about and really never asked. Shocker, but google doesn’t do much good when you type ‘dents on chainstay’ or anything like that. All the results are questions about if people are OK to ride on dented chainstays.
2- What was/is the little protruding point of metal for that sticks out of the headtube on the opposite side of the headbadge? I am not referring to a 90degree bent piece of metal that a frame pump connects to. The point of metal I am asking about is on my 87 Miyata 912 and also on a couple of entry level 86/87 Nishiki bikes I picked up to recondition and donate. I mention this because its on both lower end and higher end frames. Its only a couple cm long(guess) and is between the top tube and down tube.
A couple of burning questions I have wondered about and really never asked. Shocker, but google doesn’t do much good when you type ‘dents on chainstay’ or anything like that. All the results are questions about if people are OK to ride on dented chainstays.
05-28-15, 07:23 AM
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That little protrusion is a pump peg to help hold a frame pump in place.
05-28-15, 07:32 AM
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The inside dents are for tire clearance, the outside dent is for chainring clearance.
05-28-15, 10:15 AM
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Sunshine
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Wow, sad question, huh? thanks for clarifying. I figured it was for a frame pump, but I had only seen the type of pet that drops down and angles.
this is what I have seen-
I didn't realize this did the same job-
this is what I have seen-
I didn't realize this did the same job-
05-28-15, 12:14 PM
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it's for a frame-fit pump, which only needs one peg, almost always on the handle end
05-28-15, 05:10 PM
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A frame fitting pump can use a very simple ball bearing brazed to the HT as a peg. Or a specific machined peg as shown. Andy.
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