Seatpost problem
 

No, not another stuck seatpost thread. Actually the opposite. I ordered the wrong size, just a gnat's ass too narrow, and I don't want to deal with the return/shipping/wait for the new one. With the binder bolt pretty much fully tightened I can snug it up while on the stand but it is not tight enough to actually ride on. I was thinking just making up a shim from an aluminum can should be enough. Who here has done this and is it a reasonable workaround?

I would check your LBS and online for a seat post shim if you look you can find 1mm and 2mm shims for most seat posts that are made for this problem.

Depends on the frame and post. Maybe sell the wrong size at a discount, get the right size, and consider it a cheap lesson learned.

Shims will work, standard on some Schwinn's (Le Tours?). I wouldn't use them on a really nice bike or a really nice post.

What size is it exactly?

Yeah, I've done it many, many moons ago. I cut up an old Coke can and used trial-and-error to get the fit. It worked just fine. Not the most asthetically pleasing solution, but it will work.

I thought I was off by .2mm, but it turns out I was .4mm off. Based on my experience, the issues I see are: (1) the shim I ended up with was pretty narrow, so if you are only off by .2mm your shim will be very narrow; and (2) if the top of your seat lug has a shaped profile (as opposed to a square-cut profile), you will have an appearance issue when you bend the shim to hang it on the seat lug so it doesn't fall into the bootom bracket.

In my experience, the shim will work if it's not too thin (about 0.4 mm, for a total of 0.8). A thin shim would probably be deformed while inserting the seatpost. If I were you, I'd get a properly sized seatpost.
Just my .02.

Well, if I new, I wouldn't be here asking about a shim now would I.

Just kidding.
I did measure the frame with calipers before I ordered at 1", but considering seat post sizes vary by 10ths of millimeters, I'm fairly confident I didn't measure it exactly. OFG nailed it, an old Schwinn Le Tour that i'm building up as townie/errand runner/bar beater bike mostly with parts on hand thus aesthetics are not high on the list.

Since several of you aren't completely shooting done the shim idea i'm gonna give it a try first.

or maybe...hummmm

does anybody know if JB Weld bonds steel and aluminum?

I may have one of those shims laying around, if I do, yours for postage.

Edit: Just checked, It must have been tossed in with the boxes of crap I've been selling, I have purged most of my flipper fodder. It has a lip around the top, to keep it from falling into the seat tube, somebody here should have one.

Thanks, i'll keep that in mind.

I've done the soda can shim and it worked fine, although the shim is so thin and the fit so snug (if you get it right) that it's a bit of a challenge to fit everything together without crinkling or tearing the shim. At least they're cheap so if it takes several tries, no biggie.

A soda can is thin enough that once you get everything set and tightened, you can take an x-acto around the top of the seat lug and cut the remainder away so it doesn't show.

I was just wondering if you'd gotten a French seatpost for a non-French bike. Measure it to the nearest 0.1mm, and I (or someone else) might be willing to take it off your hands.

I wouldn't JB Weld the seatpost in place, if that's why you're asking.

0.1mm, that's asking alot from a crusty old veneir caliper in the hands of someone that has at times stopped complete strangers in a store to ask them to read the fine print on a label. :D

The post is just a generic "Laprade Type" from Harris Cyclery.

http://upload.wikimedia.org/wikipedi...rn_Leghorn.png

That's a joke, I say, that's a joke, son.

Find a beer can collector, and get a steel one.

Don't use epoxy to glue in a shim, try a couple of drops of medium CA glue. The solvent is available from Woodcraft and elsewhere so it should be totally reversible.

I've had the experience that a Laprade 26.4 mm seat post bought for a project turned out to be just over 26.2, and just didn't work. The seat tube in question was thick enough that I had my LBS hone it out for a 26.6 mm post. Much happier, because I had an old Record 2-bolt post on hand in that size that's terrific.

atmdad,

if you got a 26.6 and need a 26.8, i'm your guy.

If you have access to a lathe and a knurling tool, you can judiciously knurl the part of the post that won't be exposed to the required dia. No disaster if the knurling goes too far up the post, except it won't look so hot exposed.

I had this problem on my Trek 610, but the fitting error was much less - a 27.2 was too small, but a 27.4 was much too big. I shimmed it. I bought an assortment of brass shim at the local hardware store, and tried several thicknesses. The one that worked was (don't recall exactly) either .004 inch thickness or .006 inch thickness. It took several tries to get a shape and size that worked, and to learn how to install it (greased, all surfaces) so that the friction did not destroy the shim or bunch it. After a few installs it has a crease, but it's not a big problem.

f your discrepancy in size is "just a gnat's ass," a 1 or 2 mm shim will probably be much too thick.

Oh, just shim it with a piece of a soda can. Not a beer can; canned beer sucks. Well, maybe one of those Guinness cans with the widget would be okay (discard the widget).

+1, I've done it numerous times and it works great.

just wanted to commiserate. I had the same problem with a Le Tour and with a World Voyageur.

I ended up buying a super cheapo seatpin and spending some quality time with it and some sandpaper.

Didn't mess with the seat post last night, just hung the drivetrain and got it all dialed in.

If any one is keeping a list, Vittoria Randonneurs are a pain in the ass to mount on Sun M13II rims.

I've heard those rims are just difficult to mount tires to in general. I like the way they look though.

I have three of them on two bikes, all 27". I have no trouble putting Pasela TGs on them. Not hard at all. (The fourth rim is a Mavic MA2. So shoot me. It's on a French bike.)

That's good news. I've always wanted a pair. It'd be nice if they did a run of em in 650B