showlow

If you have a Schwinn like mine, what size seatpost are you running? I swear it says 26.6 but it's too faded to read. Lots of sources say they were made for 26.8. 26.8 makes more sense for a Tange 2 frame, imo.

Want to buy a Thomson setback, but don't want to waste my money.

Thanks.

Teamdarb

Mine measures at 26.6

Drillium Dude 

Although it states 1982, Sheldon Brown says 26.8 here: Sheldon Brown's Seatpost Size Database M-Z

DD

showlow

See. This is my dilemma... The post I have now creaks and slips on the seat rails. I guess it's OK, but a Thomson would be so much better. Love the frame.

Drillium Dude 

Yeah, the 1983 Schwinn catalog is kinda sucky compared to the earlier ones; very little info in the way of specs

If your post is creaking and slipping on the rails, the diameter has nothing to do with it. Sounds like a tightening issue or dissimilar metals. I have creaking that can't be avoided with the couple of alloy-railed saddles I have. Irritating, but...

DD

showlow

You know, I've tried tightening it to what feels like a sensible torque. It slipped ridiculous. Like, it would slide all the way back by the time I got home. Then I tightened it like I was the hulk or something. Slips a little less, but still creaks. Maybe I'll try a dif saddle. I have a cheap Kore saddle with steel rails. There is a Arione on it now.

Ps - also greased the bolt good. Have some carbon grease. Maybe I'll try that on the rails.

3speedslow

My latter Schwinn SS and also the Tempo both take 26.6.

I think Schwinn made sure their frames were reamed to what size post they had the most of.

showlow

Is reaming the seat tube out .2 mm an option?

Drillium Dude 

Without knowing specifics (type of post and saddle you're having the issue with), it's hard to pinpoint the cause of the slippage. Oh, and if you put any kind of grease on the rails when you're already having slippage issues, you're almost certainly going to continue to have slippage. Sure, the creaking may go away, but...

DD

Drillium Dude 

You could most likely do this without any issues.

DD

Scooper

In the 1983 catalog specifications, the Super Sport SP came with an SR Foursir FS-P5, micro adjustable, 26.6 mm seatpost, while the Super Sport came with an SR Laprade CT-P5, micro adjustable, 26.6 mm seatpost.

showlow

Thanks!

showlow

No grease on the rails now. Just on the bolt and post shaft. I've considered using carbon grease on the rails, which contains some kind of abrasive for use with carbon components. Supposedly it helps w/ slipping.

daf1009

Grease that helps with slipping...hmmm...now that is an interesting concept...

Tim_Iowa

It works because it has small grits in it that cause friction. Technically, it's not a grease at all, it's "assembly compound". Most formulas look like pink toothpaste.

At the bike shop I work for, we get a small packet of it with every new bike that has a carbon seatpost. We squeeze the packets out into a jar and save it. If you ask nicely at your LBS, they may give you a dab (which is all it takes for a seatpost) for free.

Tim_Iowa

Thanks. I just picked up an '83 Super Sport last week. I measured the seatpost and it was hard to eyeball the difference between 26.8 and 26.6 with my plastic harbor freight calipers.