Living in Scotland means my motorbikes are subject to a fair old battering of road salt and harsh weather. This harsh environment combined with the extreme heat coming from the engine means my exhaust headers get pretty miserable looking very quickly.
So I started doing some research into the best methods of cleaning it. Nothing short of wet sanding seemed to work though.
Until I stumbled upon a little secret to effortlessly get my exhaust headers gleaming.
It turns out hydrochloric acid reacts with rusted steel and effortlessly gets rid of it. Thats great but where do you get hydrochloric acid?
Using Harpic Bleach To Clean Motorcycle Exhaust Headers
Harpic is the answer. Harpic bleach contains 9% hydrochloric acid and comes in a handy dandy gloopy formula that is conducive to painting on with a cheap brush.
When I heard that bleach could do the trick the first thing I did was nip up to my bathroom and grab the Domestos. Turns out after a lot of messing around that Domestos may be great for toilets, but it isn’t based on hydrocholic acid like Harpic so is terrible at cleaning motorcycle exhaust headers.
As you can see my exhaust header was very heavily corroded!

I simply poured out some of the Harpic bleach into a bowl and used a cheap detailing brush to paint on the bleech.
Agitate the bleach and leave it for 3-4 minutes to start reacting.
Clean off with soapy water and repeat if necessary.
And as you can see the final result is a sparklingly clean exhaust header on my little SV650. The results are absolutely mind blowing and the effort needed was minimal!

Preventing Corrosion Of Motorcycle Exhaust Headers
So now you have your headers nice and shiny what can you do to prevent them getting back to the mess they were in?
This is a tricky one, because the extreme heat burns most things off.
The one thing I see suggested is to ceramic coat your exhaust headers… however this is expensive.
What I do is spray the exhaust headers down with ACF50 when I clean my bike. It does mostly burn off, however does seem to help slow down further corrosion.
ACF50 is magic stuff in general for preventing rust. It’s used by the air force to protect their jets, so if it’s good enough for them, then it’s good enough for our bikes! It should be a part of every motorcyclists arsenal.
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