Cleans right round the bend!

[Luddite]

Some might recall that I recommended Solvol Bluing Remover to clean up dull, bronzed headers http://www.ukmonster.co.uk/monster/s...2&postcount=12

It works really well but, at £15 for 150ml, it's not cheap.

Well, in the 'Albie Edition' of Practical Sportsbike, there's also a tip about using Harpic Power Plus to perform the same function. I'd actually heard of this before but never tried it. However, as I've got a bottle jammed behind the u-bend, I thought I'd give it a go.

I can confrm that it's just as effective as the Solvol but at a fraction of the price.

Although my pipes weren't particularly discoloured, I think you can see the 'tide mark' where I used the Harpic up to where the heat shield goes.



The second picture shows the result of the Harpic under the heat shield.



Both products contain hydrochloric acid, which is the active ingredient - it works by removing the oxygen from the oxide. The Harpic contains 9% while the Solvol is between 10 & 25%. Hydrochloric acid is, of course, corrosive but, as long as you neutralise it by rinsing with water, that's not a problem.

So, £10 per 100ml for Solvol against around 53p per 100ml for the Harpic.

Plus the Harpic leaves your exhaust smelling citrusy fresh!

[Darkness]

Have you tried sulphuric acid? That’s pretty effective at removing rust from steel.

[Luddite]

Originally Posted by Darkness

Have you tried sulphuric acid? That’s pretty effective at removing rust from steel.

No, I've not tried sulphuric. I tend to use phosphoric acid for any rust removal.

[jerry]

i have some harpic im gonna try it on the pipes tommorw

[utopia]

Hmm .. just as my environment friendly bottle of Ecover equivalent has run out.
I just might be tempted to buy something a little more brutal this time.
Thanks for the nod, Luddite ... useful stuff, as usual.

[Darkness]

It seems the main active ingredient is Formic Acid.

https://www.leebrothers.co.uk/medias...070/451860.pdf

[Darkness]

Phosphoric Acid is recommended by the British Stainless Steel Association

https://www.bssa.org.uk/topics.php?article=77

[Luddite]

Originally Posted by Darkness

It seems the main active ingredient is Formic Acid.

That's for Australia; I think they must have a different formulation over there. (Probably some environmental thing to protect the koalas.) The Euro version contains hydrochloric acid.

http://www.opinfo.ie/Images/product/...HH/RK00567.pdf



Anyway, whatever it contains, it certainly does the job.

[Jimi216]

Hands up who has bought Harpic after reading the article! ��

[Darkness]

Originally Posted by Jimi216

Hands up who has bought Harpic after reading the article! ��

Nah! Found a bottle in the bathroom.

[jerry]

tried harpic 10 on the pipes some came up shiney in 5 mins some bits still brownish after 15 mins should i trymore or rub them ????

[Luddite]

Originally Posted by jerry

tried harpic 10 on the pipes some came up shiney in 5 mins some bits still brownish after 15 mins should i trymore or rub them ????

This is what's printed in PS:

"Harpic Max Power Plus brushed liberally over the pipes and hosed-off after 30 minutes removed the corrosion. I repeated this three times.

Then, a going over with a wire brush in the drill to smooth the surface out, followed by a rub down with T-Cut metal polish (Solvol Autosol is the same) brought them back like new again."

This is pretty much what I did originally with the Solvol Bluing Remover. The discolouration will slowly return after a few hundred miles, but it's then easily removed with a wipe of the bluing remover/Harpic with no subsequent scrubbing needed.

Just make sure, if you're using a wire brush wheel, that it's stainless and hasn't already been used on any non-stainless steel, otherwise you run the risk of introducing rust spots into your pipes.

[Tim88]

I just keep mine an even golden colour with Solvol autosol. Not sure I want the chrome look. Also not sure I want to insult my bike by going at it with a bog brush and Harpic.

[350TSS]

I would use a brass wire brush rather than a steel one, it is not so aggressive and gives a nice burnish. Definitely do it somewhere where the disengaged strands (because there will be many) cannot go into the engine or near any electrics/ harnesses, they will sit there and with vibration/road buffeting they will penetrate the insulation and short something out and goes without saying a good pair of safety glasses/goggles

[chris.p]

Originally Posted by Jimi216

Hands up who has bought Harpic after reading the article! ��

Not me, but I did check out all the bog cleaners in Sainsbury’s when I did the weekly shopping, the Harpic Max Power Plus has the highest acid content of all the bog cleaners there.