Seat tube for ISP
#1
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Seat tube for ISP
I've wanted to build a bike with an ISP. In the little bit of research that I've done, I've seen that most seat post toppers are 34.9mm. Are guys only building ISP with 34.9mm seat tubes? Seems quite large. Ideally, I'd like to use 25.4 or 28.6. I'd assume that straight gauge tubing would be the way to go as well, but having never done it before, I'm really unsure.
So, what tubing should I use, and where would I get the matching seat topper?
Thanks in advance!
Brandon
So, what tubing should I use, and where would I get the matching seat topper?
Thanks in advance!
Brandon
#2
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I've wanted to build a bike with an ISP. In the little bit of research that I've done, I've seen that most seat post toppers are 34.9mm. Are guys only building ISP with 34.9mm seat tubes? Seems quite large. Ideally, I'd like to use 25.4 or 28.6. I'd assume that straight gauge tubing would be the way to go as well, but having never done it before, I'm really unsure.
So, what tubing should I use, and where would I get the matching seat topper?
Thanks in advance!
Brandon
So, what tubing should I use, and where would I get the matching seat topper?
Thanks in advance!
Brandon
#4
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You can extend the seat tube and binder up and then cut a seat post quite short for the same effect. Like this below.
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I'm not one for fawning over bicycles, but I do believe that our bikes communicate with us, and what this bike is saying is, "You're an idiot." BikeSnobNYC
I'm not one for fawning over bicycles, but I do believe that our bikes communicate with us, and what this bike is saying is, "You're an idiot." BikeSnobNYC
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What's an ISP? And if you do the really long seat tube like that Paul bike you aren't attaching the SS to the thick bit (assuming an externally butted or "bulge" ST which is generally a good idea unless you have a lug or a sleeve around there).
#6
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Thanks guys, I have actually decided not to do an ISP. Seems to be too much trouble than it's worth for what I'm trying to do.
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#7
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There's a reason why the bike frame (in steel at least) has been in it's form for so many decades. Like so many other "improvements" ISPs have had their 15 minutes of fame and we find that they are not all they wish to be. Andy
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AndrewRStewart
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"Before":
(there is no "after" pic)
This was the second frame I ever made, serial number BD2 because my fantasy bike company was Ben Dover Cycles. I even made decals.
In addition to the ISP, there were no nuts in back of the crown or front of brake bridge – brakes attached to braze-ons – but still adjustable for centering.
Braze-on front derailer too, before Campy made them. Not saying I invented the idea, but this was my own design.
All ideas I later came to regret. That and not folding the spare tubular neatly for the photo. Must have been in a hurry, to go smoke some pot or whatever the kids did back then. (Yes, I regret the hair too in retrospect, but the ladies seemed to like it OK...)
The Art Stump dropouts are not regrettable though, still some of the prettiest ever.
Mark B in Seattle
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You had under bb cables? That was pretty rare in '77.
The hair was the way everyone wore their hair back then, so that's excusable. The tire is bad though.
The hair was the way everyone wore their hair back then, so that's excusable. The tire is bad though.
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I like the Campy belt buckle. I collected a few various bike branded ones way long ago. Andy
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