Insane Tubular Conversion Question
#1
Thread Starter
Senior Member

Joined: Dec 2003
Posts: 993
Likes: 0
From: south side, you got a problem with that?
Insane Tubular Conversion Question
really, this may sound crazy, but i've talked to a BSG about it and he seemed to think it might work:
i blew the sidewall out on my favorite road wheel (front) after using it for two years of hard messengering. so i looked at it carefully and an idea came over me. i could just peel off the now paper thin sidewall/braking surface and carefully smooth out the remaining metal and convert it into a tubular rim. it seems like what remains after the peel looks just like a tubular rim.
is this possible? what are the dangers? am i crazy, stupid, or both?
i blew the sidewall out on my favorite road wheel (front) after using it for two years of hard messengering. so i looked at it carefully and an idea came over me. i could just peel off the now paper thin sidewall/braking surface and carefully smooth out the remaining metal and convert it into a tubular rim. it seems like what remains after the peel looks just like a tubular rim.
is this possible? what are the dangers? am i crazy, stupid, or both?
#2
B-
It may work, but I wouldn't trust it. It may be my lack of structural integrity issues regarding rim machining and the like, but I would worry about how the remaining pieces fit at the joint where the sidewall was removd from the rim, and how the area migt damage the tubular tire if not properly smoothed. Wouldn't a harsh angle left behind from a removed siedwall be sigificantly different from the rounded area normally found on a tublar rim? Additionally, the PSI of a tubular tire is often higher than a clincher, and I am not sure if the modified rm would offer the same support as a 'real' tubalr rim. Like I said, I am no metalurgist or structrual engineer, but this glass of whiskey is making me feel smart enough, or at least brave enough, to state the above.
It may work, but I wouldn't trust it. It may be my lack of structural integrity issues regarding rim machining and the like, but I would worry about how the remaining pieces fit at the joint where the sidewall was removd from the rim, and how the area migt damage the tubular tire if not properly smoothed. Wouldn't a harsh angle left behind from a removed siedwall be sigificantly different from the rounded area normally found on a tublar rim? Additionally, the PSI of a tubular tire is often higher than a clincher, and I am not sure if the modified rm would offer the same support as a 'real' tubalr rim. Like I said, I am no metalurgist or structrual engineer, but this glass of whiskey is making me feel smart enough, or at least brave enough, to state the above.
Last edited by pitboss; 08-09-05 at 11:14 PM.
#5
Originally Posted by Msngr
really, this may sound crazy, but i've talked to a BSG about it and he seemed to think it might work:
i blew the sidewall out on my favorite road wheel (front) after using it for two years of hard messengering. so i looked at it carefully and an idea came over me. i could just peel off the now paper thin sidewall/braking surface and carefully smooth out the remaining metal and convert it into a tubular rim. it seems like what remains after the peel looks just like a tubular rim.
is this possible? what are the dangers? am i crazy, stupid, or both?
i blew the sidewall out on my favorite road wheel (front) after using it for two years of hard messengering. so i looked at it carefully and an idea came over me. i could just peel off the now paper thin sidewall/braking surface and carefully smooth out the remaining metal and convert it into a tubular rim. it seems like what remains after the peel looks just like a tubular rim.
is this possible? what are the dangers? am i crazy, stupid, or both?
#6
Like 165 said, the main thing I would be concerned about would be the rim not being able to withstand the higher PSI of the tubular. I know, for example, that my Mavic CXP22s (clincher rims) are rated for 138psi. I wouldn't feel comfortable running tires in the realm of 190 for fear of the rim cracking mid-sprint. Yikes! Then again, to be perfectly honest. I don't really know how tubulars "work". Meaning that the pressure thing might only really be an issue with clinchers, as the bead is pushing out at the walls of the rim. Because the tubular are glued on, maybe this isn't an issue? I'd like to know. If anyone else cares to chip in their thoughts...
#7
Not-so-Senior Member

Joined: Jul 2003
Posts: 805
Likes: 0
From: Norfolk, England
Bikes: Orbea Enol roadie, Fly Micromachine BMX, Fort Track fixed
Surely the pressure in a tub is contained by the carcass of the tyre, not the rim (ie you can pump a tub up to full pressure when it's off the rim).
My main concerns would be the strucural integrity of a rim designed to be 10mm thicker than it is, and whether the tub would actually fit. In simple terms: just say no.
My main concerns would be the strucural integrity of a rim designed to be 10mm thicker than it is, and whether the tub would actually fit. In simple terms: just say no.
#8
Thread Starter
Senior Member

Joined: Dec 2003
Posts: 993
Likes: 0
From: south side, you got a problem with that?
despite all the warnings, i think i'll at least rip off the walls and file it. then i'll measure the wheel against my tubulars to see how it compares. i'll check the depth of the sitting area and the width. if those things are the same, i'll take it to Ceya and see what he says. i'm not just going to do this without being careful.
one thing i am not worried about is the strength of the rim as far as pressure from the tire goes. these rims are super strong.
one thing i am not worried about is the strength of the rim as far as pressure from the tire goes. these rims are super strong.
#10
Thread Starter
Senior Member

Joined: Dec 2003
Posts: 993
Likes: 0
From: south side, you got a problem with that?
step 1 is complete:
the clincher walls have been completely removed. it wasn't as easy as i thought it would be and i had to use rather large pliers, somewhat marking the rim wall. no big deal. the remaining edge is pretty rough, but i am reluctant to use my only file, which is pretty coarse. trackstar has a very nice set of files in the shop, and i think i'll try to borrow that set to carefully file down the detritus early next week. i'll put some old rim tape on the rim to protect it when i file, since i am a bull and these rims are a china shop, so to speak.
unfortunately, i keep my tubulars at the track, and trackstar didn't appear to have anything in stock when i poked around today. so all my measuring will have to wait until race day (wed).
ya know, if this all works --and though i am not sure it will, i am starting to think it may --i'll be surprised that it doesn't seem to be common practice. i know that i have trashed many rims, and i know others have done the same. what a great way to keep good rims going.
BTW the reason for my reluctance in buying new rims for the wheel stems from the fact that these are those 16 spoke shimano wheels with the nipples on the hub. heavy rims, yes. but tough as nails (NEVER trued in two years of being on the streets every day, except a few days of injury) and impossible to replace.
the clincher walls have been completely removed. it wasn't as easy as i thought it would be and i had to use rather large pliers, somewhat marking the rim wall. no big deal. the remaining edge is pretty rough, but i am reluctant to use my only file, which is pretty coarse. trackstar has a very nice set of files in the shop, and i think i'll try to borrow that set to carefully file down the detritus early next week. i'll put some old rim tape on the rim to protect it when i file, since i am a bull and these rims are a china shop, so to speak.
unfortunately, i keep my tubulars at the track, and trackstar didn't appear to have anything in stock when i poked around today. so all my measuring will have to wait until race day (wed).
ya know, if this all works --and though i am not sure it will, i am starting to think it may --i'll be surprised that it doesn't seem to be common practice. i know that i have trashed many rims, and i know others have done the same. what a great way to keep good rims going.
BTW the reason for my reluctance in buying new rims for the wheel stems from the fact that these are those 16 spoke shimano wheels with the nipples on the hub. heavy rims, yes. but tough as nails (NEVER trued in two years of being on the streets every day, except a few days of injury) and impossible to replace.
#12
Spoked to Death
Joined: Jul 2004
Posts: 1,335
Likes: 1
From: Boulder, CO
Bikes: Salsa La Cruz w/ Alfine 8, Specialized Fuse Pro 27.5+, Surly 1x1
Originally Posted by Msngr
BTW the reason for my reluctance in buying new rims for the wheel stems from the fact that these are those 16 spoke shimano wheels with the nipples on the hub. heavy rims, yes. but tough as nails (NEVER trued in two years of being on the streets every day, except a few days of injury) and impossible to replace.
Let us know how it works, and post pics if you can!
peace,
sam
#14
Thread Starter
Senior Member

Joined: Dec 2003
Posts: 993
Likes: 0
From: south side, you got a problem with that?
it is done. the tire has been glued on and the wheel will make its first appearance tonight at the prospect park races.
i will post pics later tonight, provided i am not in the hospital.
i will post pics later tonight, provided i am not in the hospital.
#16
Thread Starter
Senior Member

Joined: Dec 2003
Posts: 993
Likes: 0
From: south side, you got a problem with that?
well, no pics just yet (may have to wait until next week), but the whole setup works great. though the glue wasn't quite a day old, i gave it the peel back test and it passed. then i rode to prospect park taking a few tight turns at low speeds. then i raced in the park race with no problem. it would have been the equivalent of about 27 laps on Kissena, but with a lot of twists. we were playing lots of cat and mouse on the drafting and avoiding a few obstacles --all at pretty high speeds.
as of now, i am calling the experiment a success
as of now, i am calling the experiment a success
#17
Not-so-Senior Member

Joined: Jul 2003
Posts: 805
Likes: 0
From: Norfolk, England
Bikes: Orbea Enol roadie, Fly Micromachine BMX, Fort Track fixed
I'm curious as to how tight the tyre was on the rim. Did it just pop on or did it take some work to get it on? It seems you may yet prove me wrong on this
#20
Thread Starter
Senior Member

Joined: Dec 2003
Posts: 993
Likes: 0
From: south side, you got a problem with that?
i put about a hundred country miles on the wheel this weekend. no problems whatsoever, and it felt great to ride a tubie on those smooth rural roads --smoother than kissena! now i wish my rear was a tubie too. . .
sorry about the lack of pictures, i keep missing getting together with the camera. perhaps later tonight.
sorry about the lack of pictures, i keep missing getting together with the camera. perhaps later tonight.
#23
hard - i was out this past weekend (still managed some jumps on the streets of CA's bay area!), but got picked up for some transition work for the fall at the velo with a good group of 1/2/3s I think. More to follow, but it is all good. Thursday is the last "race day" for the regular season, so that will open it up completely for me after work. Nice...better late than never! thanks again Ceya - don't forget us little people when you get all famous!
#24
Thread Starter
Senior Member

Joined: Dec 2003
Posts: 993
Likes: 0
From: south side, you got a problem with that?





