Go Back  Bike Forums > Bike Forums > Bicycle Mechanics
Reload this Page >

Questions about tubeless - oily weeping?

Bicycle Mechanics Broken bottom bracket? Tacoed wheel? If you're having problems with your bicycle, or just need help fixing a flat, drop in here for the latest on bicycle mechanics & bicycle maintenance.

Questions about tubeless - oily weeping?

Old 01-28-23, 10:21 AM
Junior Member
Thread Starter
Join Date: Jun 2008
Posts: 176
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 30 Post(s)
Liked 4 Times in 4 Posts
Questions about tubeless - oily weeping?

I'm new to tubeless.

Maintaining two bikes. One's still t/l. I went back to tubes on my bike.

I noticed an oily weeping to the outside of the tires where the sealant apparently did its job. The liquid is clear and looks/feels slightly oily. It'll stay there on the tire for months, not drying up or going away.

Recently I peeled both tires off my bike. The tubeless sealant had completely dried out. There was no liquid whatsoever. Does anyone know what the oily liquid is? I used Bontrager tubeless sealant.
Telkwa is offline  
Old 01-28-23, 05:35 PM
Mad bike riding scientist
cyccommute's Avatar
Join Date: Nov 2004
Location: Denver, CO
Posts: 26,730

Bikes: Some silver ones, a red one, a black and orange one, and a few titanium ones

Mentioned: 145 Post(s)
Tagged: 1 Thread(s)
Quoted: 5815 Post(s)
Liked 3,604 Times in 2,080 Posts
It’s a glycol…likely propylene glycol. It has virtually no vapor pressure so it won’t evaporate. It can wash off the outside but the propylene glycol dissolves into the rubber which won’t wash off. You are seeing a bit of the material that has made it all the way through the rubber but the bulk of it is in the rubber itself. When you put more sealant into the tire, it will just be forced through the tire while displacing the old glycol but it won’t go away.

On a positive note, the glycol isn’t toxic as long as it is propylene glycol. If it ethylene glycol (which I don’t think is used) it is toxic if you lick it. But to paraphrase the old “Doctor! Doctor!” joke, don’t lick your tires.
Stuart Black
Gold Fever Three days of dirt in Colorado
Pokin' around the Poconos A cold ride around Lake Erie
Dinosaurs in Colorado A mountain bike guide to the Purgatory Canyon dinosaur trackway
Solo Without Pie. The search for pie in the Midwest.
Picking the Scablands. Washington and Oregon, 2005. Pie and spiders on the Columbia River!
Days of Wineless Roads. Bed and Breakfasting along the KATY
Twisting Down the Alley. Misadventures in tornado alley.
cyccommute is offline  
Likes For cyccommute:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell or Share My Personal Information -

Copyright © 2023 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.