Tuesday, February 28, 2012

Protip: Soften Carb Boots & Remount Carbs

Wintergreen oil + Xylene mixed in a certain proportion
can soften hardened rubber carb  insulator boots.

Leave them to soak overnight
in the mix of 70% Xylene and 30% Wintergreen oil
The result is clean and pliable insulator boots that are much easier to install.

They should pop right on with no fuss.
Getting the carbs mounted on them can still be a fist though.
An easy fix it to wrap a ratchet strap around the carbs and front of motor.
Tighten down on the ratchet until the carbs pop into the boots and that's it.
Button everything up and you're done.
Soft boots can turn a day of struggles and headaches (and broken boots)
into about a 30 minute re-install, from start to finish.


  1. I've heard about this, works for other rubber things too. Where do you get each?

    1. The wintergreen oil I sourced from a local supplier. It's easy to find if you know where to look: places that sell herbal "healing" supplements, scents and incense, etc... If all else fails you can get the wintergreen oil on ebay.

      The Xylene is a lot easier to source; any hardware store should have it with the paint thinners. I got mine at Home Depot.

  2. I have never heard of either of these substances.

    1. Wintergreen Oil (Methyl Salicylate) is used in some pretty common things:
      It's used in pesticides and bug repellents.
      In analgesics, such as Bengay.
      It's in Listerine mouth wash.
      It is toxic in its pure form, so do not drink it, and I'd recommend wearing gloves to be safe. It will take a fair amount to harm you, but it's better to be safe than sorry.

      The Xylene is just another form of solvent. It's often used as a substitute for paint thinner when a slower dry is desired.
      It's also commonly used to clean substances such as metal, leather, and of course; rubber.

  3. Love your blog. Do you work at Brooks? I'm in Fairfax and I take my bike(s) to brooks. I'm using this particular tip for my '81 cb750 project - softening the boots.

  4. holy crap. I just tried to pull the rubber-boots off of the motor they are stuck on there damn good. any thoughts on getting them off without destroying them?