Gritty couplers

[Matthew Strongin]

I'm hoping one of you framebuilder, master mechanic, bike whiz types can help me out. After a particularly sandy ride today I pulled my S&S coupled bike apart to drain any water and re-grease the threads on the couplers. In doing so I noticed that the coupler on the downtube has a really gritty feel (and sound) when you rotate it. It doesn't seem to affect getting a hold of the threads on the other side of the coupler during assembly and tightening it down feels smooth and normal. But when open and I spin it around, it sounds like there's a bunch of sand in there. The top tube coupler is smooth and silent. Any tips for cleaning this out, or is it nothing to worry about?

Thanks in advance!

[AngryScientist]

you probably did get some sand in the loose end.

i would take it apart again and flush it out with a ton of WD40 or something similar, then re-grease. i bet there is just some grit trapped in there that the spray will flush out.

by the way, are these Ti or Stainless we're talking about?

[donevwil]

Not a framebuilder, but have had the same experience with my S&S bike that was also my Winter bike. It wasn't a problem until I disassembled the frame (and noticed the problem) and reassembled it after cleaning only the coupler teeth. The frame now creaked slightly so I disassembled again and blew it with compressed air until it was bone dry and didn't sound gritty (as you detailed). Re-assembled with grease and wrapped the coupler with electrical tape. I would like to find a classier solution, however.

[Jacques]

Blow it out with compressed air.

[Matthew Strongin]

Thanks for the tips! I took everything back apart for now so the frame can completely dry out. These are stainless on a steel frame. I'll give the compressed air a go to cut down on the mess and then try WD-40 if that doesn't work. I've thought of stretching a cut bit of old MTB tube around the couplers to keep gunk out, but never got around to trying it.

[velobran]

Should have ridden the Parlee ... or the Spooky.

[TJ]

Should have ridden the Parlee ... or the Spooky.

Or you all could come ride here where it's to cold for anything to stick to metal

[velobran]

Or you all could come ride here where it's to cold for anything to stick to metal

Tongues - I bet tongues stick to metal.

[Matthew Strongin]

Or you all could come ride here where it's to cold for anything to stick to metal

As enticing as that sounds, I'll stick to the sandy wet roads. Tomorrow I'll head out with it in the 40s...and I'll be wearing every piece of kit I own to stay warm.

[TJ]

As enticing as that sounds, I'll stick to the sandy wet roads. Tomorrow I'll head out with it in the 40s...and I'll be wearing every piece of kit I own to stay warm.

I would imagine every piece of kit I own means two diff things to you and I

[Matthew Strongin]

I would imagine every piece of kit I own means two diff things to you and I

It may actually mean two different things to me, but I was envisioning myself wearing a pile of jerseys and looking like the stay puft marshmallow man.

[TJ]

All relative. 40's here means base layer, jersey, wind breaker, shorts and knee warmers. Pretty sure if I lived down there 40 would be freezing

[velobran]

All relative. 40's here means base layer, jersey, wind breaker, shorts and knee warmers. Pretty sure if I lived down there 40 would be freezing

People will be out in winter coats. Fer realz.

I pulled out my thermal tights to wear, but it may be in the 50's by the end of the ride - so I'll have to stick with knee warmers and a nice softshell gilet (jill-eh).

[j44ke]

Not a framebuilder, but have had the same experience with my S&S bike that was also my Winter bike. It wasn't a problem until I disassembled the frame (and noticed the problem) and reassembled it after cleaning only the coupler teeth. The frame now creaked slightly so I disassembled again and blew it with compressed air until it was bone dry and didn't sound gritty (as you detailed). Re-assembled with grease and wrapped the coupler with electrical tape. I would like to find a classier solution, however.

I saw a tandem with inner tube sections slipped over the couplers. I can't remember whether it was just the lower ones, but I do remember wondering why the heck they were there. Makes sense now.

[jBay]

I'm hoping one of you framebuilder, master mechanic, bike whiz types can help me out. After a particularly sandy ride today I pulled my S&S coupled bike apart to drain any water and re-grease the threads on the couplers. In doing so I noticed that the coupler on the downtube has a really gritty feel (and sound) when you rotate it. It doesn't seem to affect getting a hold of the threads on the other side of the coupler during assembly and tightening it down feels smooth and normal. But when open and I spin it around, it sounds like there's a bunch of sand in there. The top tube coupler is smooth and silent. Any tips for cleaning this out, or is it nothing to worry about?

It's too late to advise you to ask the builder to use the "correct" coupler orientation on the down tube. To avoid the problem you have experienced, the coupler should be oriented so that the nut is on the bottom bracket end of the down tube and the threaded portion of the coupler is on the head tube end. In that orientation, the coupler is essentially self-sealing and grit and water don't get in.

The ghetto solution is a coupler condom. Split the frame and slide a portion of an old inner tube over one end of the down tube. You can then pull the inner tube over the coupler when the frame is reassembled and this problem will be prevented. A friend recommends Parafilm, but I haven't tried it myself.

To thoroughly clean the nut, separate the frame. You can then remove, clean and refit the coupler nut, following the directions on the S&S website.

Hope this helps,
John

[Matthew Strongin]

It's too late to advise you to ask the builder to use the "correct" coupler orientation on the down tube. To avoid the problem you have experienced, the coupler should be oriented so that the nut is on the bottom bracket end of the down tube and the threaded portion of the coupler is on the head tube end. In that orientation, the coupler is essentially self-sealing and grit and water don't get in.

The ghetto solution is a coupler condom. Split the frame and slide a portion of an old inner tube over one end of the down tube. You can then pull the inner tube over the coupler when the frame is reassembled and this problem will be prevented. A friend recommends Parafilm, but I haven't tried it myself.

To thoroughly clean the nut, separate the frame. You can then remove, clean and refit the coupler nut, following the directions on the S&S website.

Hope this helps,
John

Thanks John. I do have a project in the works for another S&S bike, so I'll make sure to talk to the builder about the coupler orientation. Too late on the current frame. I'll try the compressed air before I start taking the coupler apart, but I appreciate the link. If the air doesn't work, I'll give it a go.

[zetroc]

Here's the coupler orientation John's talking about. I've had zero problems with grit getting in here.


hampsten strada bianca by cortezcycles, on Flickr

[j44ke]

So is the orientation of the lower coupler a well-known solution or part of S&S's own spec? I just looked through the gallery of a builder who does an awful lot of S&S retrofits, and not one of them had the lower coupler oriented as pictured above. I'm not questioning the solution, just wondering why other builders aren't doing it as a matter of course.

[lukasz]

Mine isn't like that either. I've not had a problem with gritty couplers. Sure, I've gotten crap in the threads sometimes. I just cleaned it off and went about my business. I race cross on this bike.

[donevwil]

My bike mentioned above was fabricated as recommended, nut on BB side. Ultimately, after a few years and enough wet rides, it developed the gritty coupler. Not a big issue, but it can happen with either coupler orientation if one rides in the muck often enough. Regardless, I'd recommend a coupler condom for anyone who doesn't break it apart once a year or so yet rides in the wet often .