How Hard to Inadvertently Bend Steel Frame?
#1
Newbie
Thread Starter
Join Date: Aug 2014
Posts: 1
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
How Hard to Inadvertently Bend Steel Frame?
This is probably a ridiculous question but I'm wondering how hard it is to inadvertently bend a steel frame. I have a Surly Long Haul Trucker Deluxe (the one with S&S couplers) and I jumped a bit to quickly put all of my weight (about 150 lbs) on the top tube to see if there was enough air in the bike tire. I'm guessing that I'm being overly paranoid but is there any way I would be able to bend the top tube by quickly putting my weight on it? There's no distinct bending in the frame but I'm wondering how I might go about checking for minor bending. Thanks!
#4
Senior Member
Join Date: Aug 2005
Location: Pittsburgh, PA
Posts: 33,656
Bikes: '96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '20 Surly Midnight Special, All are 3x10. It is hilly around here!
Mentioned: 39 Post(s)
Tagged: 0 Thread(s)
Quoted: 2026 Post(s)
Likes: 0
Liked 1,095 Times
in
741 Posts
Unthread the coupler nut in the top tube, then start and tighten the nut again. If it unthreads and rethreads smoothly, the top tube is still straight.
#5
Senior Member
Join Date: Oct 2011
Location: Fairplay Co
Posts: 9,513
Bikes: Current 79 Nishiki Custum Sport, Jeunet 620, notable previous bikes P.K. Ripper loop tail, Kawahara Laser Lite, Paramount Track full chrome, Raliegh Internatioanl, Motobecan Super Mirage. 59 Crown royak 3 speed
Mentioned: 26 Post(s)
Tagged: 1 Thread(s)
Quoted: 789 Post(s)
Liked 1,739 Times
in
630 Posts
I doubt you could bend better quailty strait steel gage frame icendentally. I have crashed sinilar frames into curbs at 20miles an hrs that held up fine. And I no others that readily ride them down stairs no issues.
Last edited by zukahn1; 08-05-14 at 07:31 PM.
#6
Senior Member
Join Date: Apr 2009
Location: New Rochelle, NY
Posts: 38,671
Bikes: too many bikes from 1967 10s (5x2)Frejus to a Sumitomo Ti/Chorus aluminum 10s (10x2), plus one non-susp mtn bike I use as my commuter
Mentioned: 140 Post(s)
Tagged: 1 Thread(s)
Quoted: 5767 Post(s)
Liked 2,541 Times
in
1,407 Posts
The human eye is amazingly sensitive. If you sight down the tube like a ***** you'd be able o spot any bend.
But I'd be amazed if you discovered a bend. These tubes are extremely strong, and are much easier to dent then bend.
But I'd be amazed if you discovered a bend. These tubes are extremely strong, and are much easier to dent then bend.
__________________
FB
Chain-L site
An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
One accurate measurement is worth a thousand expert opinions - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
FB
Chain-L site
An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
One accurate measurement is worth a thousand expert opinions - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
#7
Senior Member
Join Date: Oct 2011
Location: Fairplay Co
Posts: 9,513
Bikes: Current 79 Nishiki Custum Sport, Jeunet 620, notable previous bikes P.K. Ripper loop tail, Kawahara Laser Lite, Paramount Track full chrome, Raliegh Internatioanl, Motobecan Super Mirage. 59 Crown royak 3 speed
Mentioned: 26 Post(s)
Tagged: 1 Thread(s)
Quoted: 789 Post(s)
Liked 1,739 Times
in
630 Posts
Yes look close I have never seen a bent tube that did not have at least one fairly visible ding or flaw. But Don't look to close becease you will see a lot of flaws on nearly any lesser production bike that don't realy matter.
#8
Senior member
Join Date: Oct 2004
Location: Oakville Ontario
Posts: 8,115
Mentioned: 25 Post(s)
Tagged: 0 Thread(s)
Quoted: 942 Post(s)
Liked 656 Times
in
370 Posts
I dunno about bending the tube but quickly putting your weight on the top tube with that part of the anatomy that is normally poised over it, YIKES!
#9
Banned.
Join Date: Jun 2010
Posts: 434
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 29 Post(s)
Likes: 0
Liked 1 Time
in
1 Post
I broke the braze, where the seat tube connects to the bottom bracket, of a steel frame about 20 years ago. The nice thing about steel is how easy it is to fix. I don't think I'll have as easy a time fixing a break in my aluminum frame.
#11
Bicycle Repair Man !!!
My brother in law drove his Surly LHT into the back of a car at close to 30 miles per hour... he bent the fork beyond belief and only put a minor bend in the frame.
Overbuilt is an apt word when it comes to describing how tough these frames are.
Overbuilt is an apt word when it comes to describing how tough these frames are.
#12
Seņor Member
Join Date: Feb 2013
Posts: 5,066
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 649 Post(s)
Liked 292 Times
in
215 Posts
i have been around or above 200 lbs since i was a teenager
and me and a friend used to race down a certain hill sitting sidesaddle on our top tubes
of a much lighter steel frame than a lht
i am not saying it was a good idea
just that you have absolutely nothing to worry about
and me and a friend used to race down a certain hill sitting sidesaddle on our top tubes
of a much lighter steel frame than a lht
i am not saying it was a good idea
just that you have absolutely nothing to worry about
#13
working on my sandal tan
Join Date: Aug 2011
Location: CID
Posts: 22,627
Bikes: 1991 Bianchi Eros, 1964 Armstrong, 1988 Diamondback Ascent, 1988 Bianchi Premio, 1987 Bianchi Sport SX, 1980s Raleigh mixte (hers), All-City Space Horse (hers)
Mentioned: 98 Post(s)
Tagged: 0 Thread(s)
Quoted: 3870 Post(s)
Liked 2,563 Times
in
1,577 Posts
Or pinching the tire as a bare minimum... jumping on the bike makes no sense -- if it doesn't pinch-flat, you have enough air?
#14
Passista
Join Date: Jul 2005
Posts: 7,596
Bikes: 1998 Pinarello Asolo, 1992 KHS Montaņa pro, 1980 Raleigh DL-1, IGH Hybrid, IGH Utility
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 866 Post(s)
Liked 720 Times
in
395 Posts
It's extremely unlikely you can bend a good quality steel tube like that just by putting your weight on it.
#15
Banned
Ive inadvertently ridden over a concrete wheel stopper block which was across one lane of the street ,
at night in the dark .. (inadequate lights)
went over it, didnt end up on my face , but the downrube suffered a rumpling bend. from the fork coming back.
I imagine once the S&S coupler is disconnected bending the tubes is relatively easy ,
because of the leverage of the length of the tube.
at night in the dark .. (inadequate lights)
went over it, didnt end up on my face , but the downrube suffered a rumpling bend. from the fork coming back.
I imagine once the S&S coupler is disconnected bending the tubes is relatively easy ,
because of the leverage of the length of the tube.
#16
Banned.
Join Date: Jun 2010
Posts: 434
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 29 Post(s)
Likes: 0
Liked 1 Time
in
1 Post
Thermionic? Isn't that an out-dated super-power, now that transistors have replaced tubes? I never saw your comic books.
#17
working on my sandal tan
Join Date: Aug 2011
Location: CID
Posts: 22,627
Bikes: 1991 Bianchi Eros, 1964 Armstrong, 1988 Diamondback Ascent, 1988 Bianchi Premio, 1987 Bianchi Sport SX, 1980s Raleigh mixte (hers), All-City Space Horse (hers)
Mentioned: 98 Post(s)
Tagged: 0 Thread(s)
Quoted: 3870 Post(s)
Liked 2,563 Times
in
1,577 Posts
Thermionic? Isn't that an out-dated super-power, now that transistors have replaced tubes? I never saw your comic books.
Thread
Thread Starter
Forum
Replies
Last Post
cazzooo
Bicycle Mechanics
4
03-24-11 08:12 AM