Fuel Treatment - Gimmick?

[Timbollew]

Hiya guys so bikes been running a little rough and I really don't wanna take the carbs out again. Fuel treatments like redex and stuff, they any good or just clever marketing?

[darrsi]

The ONLY one that has ever done anything noticeable on my bike is STP Complete Fuel System Cleaner, which I tend to use just once a year.
Never noticed any change whatsoever with Redex, etc, with any bikes I have ever used them on.

[Bretty]

I'll usually put redex in mine at a very high concentration (whole bottle to half a tank)
Straight after I bring it out of winter storage.
It usually runs lumpy after being sat for a while as I don't drain the carbs, so I guess there'll be deposits from evaporated fuel in the carbs. After a good run it then runs like new.

The only thing I did find when I recently rebuilt my engine was a purple/red oxidation over the piston, valve heads and plugs. I assumed it was just running hot, but recently looked at a spark plug diagnosis diagram that suggested red deposits were the result of fuel additives.

No harm done, just an observation.