Bike shop adjusts saddle height during puncture repair

they've prob nicked your bling seatpost & replaced it with some gaspipe. have another look *taps nose*

My LBS have a workstand with a gas pipe seat post clamped into it. When they put a bike on the workstand they whip out the seat post and stick the gas pipe seat post into the seat tube. It does mean that whenever they service it my seat ends up at a slightly different height, but it doesn't bother me too much (I've just put a subtle mark on my seat post so it's never a difficult job to pop it back to the right height).

novembercp wrote:

Graeme_S wrote:

My LBS have a workstand with a gas pipe seat post clamped into it. When they put a bike on the workstand they whip out the seat post and stick the gas pipe seat post into the seat tube. It does mean that whenever they service it my seat ends up at a slightly different height, but it doesn't bother me too much (I've just put a subtle mark on my seat post so it's never a difficult job to pop it back to the right height).

Really? Assuming you're not joking, this would make sense. Of course if they do this, they should make a subtle mark to get it back to the right height. Not sure if I trust this LBS anyway. While I was there I saw the spannerman pump up a tyre, seconds later the tyre exploded and he says 'what was that?'

most mechanics clamp bikes by the seat post. yours may have needed more space to get the clamp on to it so the seat was raised. i always return it to the original height after a service.

the Gas pipe story dont belive it as most seat posts are not the same size and if the pipe was not the correct size the seat tube would be damaged when trying to tighten it up to get clamping force.

My seat post had been gradually sliding down as I was riding...At first I thought I was going mad, but I could gradually touch the ground with more and more of my foot. I also got the feeling I was starting to ride an BMX!!!...It's amazing how much difference 1/2 an inch more or less on your seatpost makes to the feel of your bike.

The bike was an unwanted rebuild that I turned into my commuter, so I thought I'd been given the wrong seat post by my mate.

Took it to and LBS, but the 27.2 seatpost wouldn't fit and no matter how tight I did the seatpost QR up the 27.0 would still slip down

The solution, cut up a diet coke can and use it as a shim, it worked!
.

how much did your fawlty towers of a LBS charge for a puncture repair?

just interested...

if your seat is slipping and you have a Qr collar setup replace it with a bolted one.

if it is part of the frame you have less choice.

novembercp wrote:

Got a puncture recently on way to work, didn't want to fix it myself when in my work clothes so got it fixed by LBS.

Got it back, great job but they seem to have raised my saddle a bit! Made me realise I had it too low, but thats beside the point . Why would they do this? Took a test ride? Took off the saddle in order to fix the puncture?

As already mentioned, most bike shops use clamps that hold the bike by the seatpost. The clamps are typically 4"-5" tall, so you need that much exposed searpost (in one bit) to get it into the clamp.
Lots of bikes (especially commuters with lights and mudguards) don't have this much space, so the saddle height needs adjusting to get the bike into the stand. It's best practice/common to mark the height before moving it, though, so you can readjust it exactly back.

I'm sure there's more to the gas pipe story. I can't think of a way to get the same size tube be clamped securely by _all_ bikes. You can sometimes (with a bit of frame damage) get away with ~0.4mm smaller or thereabouts smaller post than hole, but it never really gets secure, and you damage the frame.

some bike shops will take your post out and use one of thiers if they feel it may scratch the post / post too short to still be in the bike and clamp into the stand