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Old 04-04-08, 09:25 AM   #1
Cone Wrench
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Using a work stand

I have an Ultimate work stand and I just hang the top tube in the clamp. However, most people seem to clamp the seat post. Why is this? What is the advantage?
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Old 04-04-08, 09:33 AM   #2
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With some thin-walled tubing you run the risk of denting the tubing if you use the top-tube and exert too much pressure. Using the seat post is standard practice in most workshops.
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Old 04-04-08, 09:38 AM   #3
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Depending on how your cables run you can have interference if you clamp them against the top tube.
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Old 04-04-08, 09:41 AM   #4
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In addition to the points made by the other posters, there is potential for marring your paint too.
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Old 04-04-08, 09:55 AM   #5
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With some thin-walled tubing you run the risk of denting the tubing if you use the top-tube and exert too much pressure. Using the seat post is standard practice in most workshops.
Or if it is carbon fiber, you could crack the tubing. If there is something embedded in the clamp you could score the tubing causing a weak point.
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Old 04-04-08, 10:10 AM   #6
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I normally clamp my bikes by the top tube but I'm working on steel, Ti or relatively heavy-wall Al and I'm careful how much clamping pressure I use. For carbon, or light Al, the seatpost is the safer clamp location.

I recommend getting the cheapest seatpost of the right diameter you can find and dedicating it to workstand use. An MTB length seatpost gives you more height options too.
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Old 04-04-08, 10:28 AM   #7
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All the above posters clearly pointed out the merits of using the seatpost clamping method and as a previous postersaid, it's pretty much an industry "best-of" practice. Regardless of the material or bike, we always clamp using the seatpost. It takes a couple extra seconds but we 1). mark seatpost height w/ a piece of electrical tape at the top of the collar 2). Measure & record seatpost height and record it on the repair slip
3) than we can raise or remove the seatpost (for high end posts, we end up using a "dummy" cheap, inexpensive post like a dimension or like or we wrap the seatpost with a shop rag before clamping it)

It takes a couple extra seconds but this way I've never had an issue with dimpled frames, crushed tubes, marred paint/ decals..
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Old 04-04-08, 03:33 PM   #8
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park tool actually even makes a seatpost just for sticking in framesets without a seatpost (at the time) to clamp into a workstand.

Last edited by GlassWolf; 04-05-08 at 04:05 AM.
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Old 04-04-08, 11:37 PM   #9
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I have noticed more than 1 mechanic at different shops just hang the nose of the seat over the clamp. Is this something that is common in other shops? I have never done this at home, but then again all my bikes are very large (62cm and up) steel lugged tanks. Is this something that is done frequently with the ultra lightweight c/f bikes?
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Old 04-05-08, 05:13 AM   #10
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Hanging the bike via the seat on the stand is a mechanics "cheat". For quick jobs i.e. checking tire pressure, etc. some mechanics think it is easier to hang the bike than go through the hassle of clamping it properly. I'm not a fan of said practice as it is all too easy for the bike to slip off or someone bump into it and you than have the issue of scratched, dented, etc. that we were trying to avoid in the first place.
Different strokes for different folks but I learned long ago, do the job right once and you prob/ won't have a problem.
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Old 04-05-08, 05:42 AM   #11
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I have noticed more than 1 mechanic at different shops just hang the nose of the seat over the clamp. Is this something that is common in other shops? I have never done this at home, but then again all my bikes are very large (62cm and up) steel lugged tanks. Is this something that is done frequently with the ultra lightweight c/f bikes?
This is not a good practice. You run the risk of damaging the seat this way. More so with cheap/abused seats on heavy bikes than it is on lightweight cf bikes. With the exception of really, really expensive seats. Why chance it?

Having said that, i've been guilty of doing this with my own bike a couple of times - I wouldn't do this on a customers bike though.
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Old 04-05-08, 07:46 AM   #12
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Customer riding bike too large for them with not enough seatpost exposed to clamp + frozen seatpost = hanging by the seat for small repairs.

While I also agree it is not a good practice to do this, just yesterday I had one heck of a time with a customer's seatpost due to them installing it sans any grease or assembly lube. The frame was a swoopy carbon Orbea...no chance of clamping the frame. Had to pull the post with much effort, clean both the post and the frame and reinstall with carbon prep....all just to clamp the bike and perform a task unrelated to the seatpost. That's a bit of labor and materials I can't charge for, so I can understand other busier mechanics using the shortcut.

BTW, the other work I was performing involved fixing their home BB installation w/o a torque wrench.
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Old 04-05-08, 07:52 AM   #13
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Customer riding bike too large for them with not enough seatpost exposed to clamp + frozen seatpost = hanging by the seat for small repairs.

While I also agree it is not a good practice to do this, just yesterday I had one heck of a time with a customer's seatpost due to them installing it sans any grease or assembly lube. The frame was a swoopy carbon Orbea...no chance of clamping the frame. Had to pull the post with much effort, clean both the post and the frame and reinstall with carbon prep....all just to clamp the bike and perform a task unrelated to the seatpost. That's a bit of labor and materials I can't charge for, so I can understand other busier mechanics using the shortcut.

BTW, the other work I was performing involved fixing their home BB installation w/o a torque wrench.
Since it sounds like a home build, I'd have charged them for the time at least, considering all of the problems seem to stem from shadetree mechanic lack of skill in doing everything themselves, trying to save a few bucks.
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Old 04-05-08, 08:12 AM   #14
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Originally Posted by Locomotion81 View Post
Hanging the bike via the seat on the stand is a mechanics "cheat". For quick jobs i.e. checking tire pressure, etc. some mechanics think it is easier to hang the bike than go through the hassle of clamping it properly. I'm not a fan of said practice as it is all too easy for the bike to slip off or someone bump into it and you than have the issue of scratched, dented, etc. that we were trying to avoid in the first place.
Different strokes for different folks but I learned long ago, do the job right once and you prob/ won't have a problem.
That's becoming more of a problem. I've encountered a few carbon frame bikes that have shaped frame tubes and shaped seat posts that don't have any good options for clamping in a conventional work stand.

High dollar bike and no good way to clamp it. That's a disaster waiting to happen.
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Old 04-05-08, 08:33 AM   #15
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That's becoming more of a problem. I've encountered a few carbon frame bikes that have shaped frame tubes and shaped seat posts that don't have any good options for clamping in a conventional work stand.

High dollar bike and no good way to clamp it. That's a disaster waiting to happen.
This is going to become a worse problem as more high-zoot frames adopt the "intergrated seatpost" design where there is nothing to remove except the saddle and no way to expose additional seatpost.

The "Pro" type workstands that support the bike by the bottom bracket and one set of dropouts (Park's PRS-20 for example) will be a necessity in any bike shop that has high end bikes to deal with.
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Old 04-05-08, 08:36 AM   #16
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Bontrager makes a clamp assembly for grasping oddly shaped aero seatposts...it clamps the seatpost and than you can clamp this cyclindrical tube that comes off of it. It works very nice for cervelos, specialized tri bikes, etc.

Yeah, it is a shame that sometimes our shop skills, time, and materials get used just to get the bike in a position to work on it. I try to avoid putting myself or my employees in a position to do that by adding a "contingency" of $5-10 on repair write-ups. The customer sees the estimated price of the repair plus another line of 5-10 extra that we explain for those "little things that help us make your bike a little better". That way when something unforeseen like a stuck post comes up, at least I can get he cost of the materials out of the otherwise lost time. Even so, 99% of the time we come back in under the estimate.....our customers are happy and we're not burned. If somebody throws a fit about it, we write on the estimate to not do anythign other than the repair and call if something else is a problem.
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Old 04-05-08, 06:40 PM   #17
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That's becoming more of a problem. I've encountered a few carbon frame bikes that have shaped frame tubes and shaped seat posts that don't have any good options for clamping in a conventional work stand.

High dollar bike and no good way to clamp it. That's a disaster waiting to happen.
park makes a replacement seatpost that clamps to any diameter seattube for just this purpose - good to have if your shop deals with high end zoot ****. Carbon post comes out, clamper goes in and done.
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Old 04-05-08, 06:47 PM   #18
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park makes a replacement seatpost that clamps to any diameter seattube for just this purpose - good to have if your shop deals with high end zoot ****. Carbon post comes out, clamper goes in and done.
This won't help if the stock seat post is "aero" (non-round) in cross section or is permanantly a part of the frame like the newest integrated ones.
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Old 04-05-08, 07:24 PM   #19
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This won't help if the stock seat post is "aero" (non-round) in cross section or is permanantly a part of the frame like the newest integrated ones.
Luckily we're not that type of shop. I guess the final option would be to run something like the Park "extreme range clamp" - we mostly use this on recumbents but I don't see why it wouldn't work on aero tubing on the main triangle.
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Old 04-05-08, 07:39 PM   #20
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This won't help if the stock seat post is "aero" (non-round) in cross section or is permanantly a part of the frame like the newest integrated ones.

And then there's this http://www.parktool.com/products/det...&item=100%2D6X
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Old 04-05-08, 07:53 PM   #21
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e.g what I said
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Old 04-06-08, 06:31 PM   #22
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we clamp the seat post as close as possible to the seat post clamp, [IMG][/IMG]
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Old 04-06-08, 08:26 PM   #23
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[QUOTE=suhinaffy;6472693]we clamp the seat post as close as possible to the seat post clamp, [QUOTE]

how do you clamp bikes with integrated aero tube posts like a kuota kebel or the look 959, or any number og TT bikes?
just curious
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Old 04-06-08, 08:38 PM   #24
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That's your shop?
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Old 04-07-08, 01:31 AM   #25
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[QUOTE=GlassWolf;6473304][QUOTE=suhinaffy;6472693]we clamp the seat post as close as possible to the seat post clamp,
Quote:

how do you clamp bikes with integrated aero tube posts like a kuota kebel or the look 959, or any number og TT bikes?
just curious
we dont get to play with those kind of bikes.
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