Melted Bellows Muck

[Coyote]

I just received a complete set of carbs I bought off eBay. Very nice shape overall -- except for the familiar melted slide bellows. God that stuff is horrible. Get it on you and it spreads like a disease.
Is there anything made by man that will dissolve this gooey black muck? I wonder if I can burn it off

[yeadon_m]

Horrible job! Physically scrape off the bulk of it once stripped into smallest parts, then carb cleaner and lots of patience will do it.
Good luck
Mike

[Cliff]

What makes them melt?? I still have the originals on my bike but almost every carb rack I've seen they've melted!

[old racer]

Acetone should clean that off,But wear gloves.

[Coyote]

One thing for sure is you can't blame it on ethanol. They've been melting way longer than that. I'm sure it doesn't help matters, but it's not the cause. The real bummer is the stupid price to replace them.

[yeadon_m]

I believe its photodegradation / oxidation. They can survive a long time stored cool in the dark in their packets, but 30 year old bellows are still not as good as newly made ones, so its more than light alone.
On bikes in the open they all eventually turn into nasty degraded goo.
My guess is they used what we'd now call an inferior material! the upper arm boots don't fail in the same way, so they must be made of summat else!
Mike

[Coyote]

Yep Mike. Upper boots (I call them knee boots) are fine. The rubber even feels different and thinner when new. They loose their flex over time and usually split from being brittle. But I have never seen them melt.