I have used "Plexus" for years on Lexan windows on my Drag Race cars. It makes them last and they don't dull or craze. Cleaning plastics in the case of clear plastics should really be done in an up and down motion or a sideways back and forth motion. One or the other. Never in a circular pattern. This causes that dull surface crazing 'fine cracks" to appear quicker.
The use of nearly all window cleaners on any plastics is a No-No. Even if the container says its safe for plastics. As nearly every one of them contains Ethyl or Methyl alcohol and even Glycol ether, and like any strong solvent. Such as "acetone" will clean yes but its use is a No-No on any plastics as it draws out the plastics essential oils. On clear plastics especially as it can be easily seen. It causes crazing on both Plexiglass and Lexan a dull surface will be the result.
Look for plastic cleaners with a "Surfactant" in it. Which is really what all soap is. It's a wetting agent that takes away surface tension like plain water has and allows the chosen cleaning product to work against the solid surface. Allowing it to more easily penetrate the plastics surface and do its job. It allows the cleaning product to penetrate and get under the grime to help the water to lift it away.
Its also a surface tension lubricant. So is shaving cream, the surfactants in shaving cream allow a razor to glide across the surface more easily. We all know shaving with a razor without is not that fun.
An alternative to "Plexus" and at about half the cost as it isn't in an aerosol can. Is "Plaskolite" Plastic Cleaner. It's available at about any hardware store that may not have "Plexus" brand. It will be in the section where they might sell items to repair or replace your houses Screendoors and pieces of "Plexiglass" panels for the same thing.
"Plaskolite" plastic cleaner. (Pictured below) Its recommended for "Duraplex", "Optix" and "Lexan". It has anti static properties. It brings back a shine on dirt bike goggles, Plastic lenses on eyeglasses and safety glasses, motorcycle windscreens, even painted surfaces with clear coats.
It does a real nice job on dirt bike plastics as well after a good cleaning. It cleans and polishes and make the bike easier to wash after a good thrashing too. If its safe for prescription lens glasses it will work on your dirt bikes plastics and is probably one of the safest products you can use.
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