Use Harpic to clean exhaust

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Re: Use Harpic to clean exhaust

Post by nortyrascal » Tue Apr 04, 2017 11:41 am

I cleaned my pipes at the weekend with Harpic and I was very impressed. It contains 9% Hydrochloric acid so I put a black bin liner behind the headers and removed the belly pan as the stuff will damage engine cases and paintwork at that concentration.

As soon as the stuff goes on you can see it reacting with the rust on the pipes. I left it for a couple of minutes and then agitated it with a green scotchbrite. Then I rinsed it off. The whole process took about half an hour.

Here are a couple of before and after pics. The before was taken about 3 months ago so if anything the pipes were a little worse than the pic. The after pics shows the result with Harpic and scotchbrite. They still need finishing off with some Solvol but I think it's good result.

I won't be going back to Solvol and wire wool method. Just make sure you mask the bike off so you don't get any splashes on the rest of the bike.


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pipes.jpg (34.99 KiB) Viewed 7664 times

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Re: Use Harpic to clean exhaust

Post by Boggs » Tue Apr 04, 2017 12:03 pm

Don't use toilet duck,it just left me with a huge bill.


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Re: Use Harpic to clean exhaust

Post by Dirk » Tue Apr 04, 2017 7:04 pm


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Re: Use Harpic to clean exhaust

Post by TomBoyNI » Thu Apr 06, 2017 1:38 am

I just watched this guy do the exact same thing. I wouldn't be doing it though. :ohmy:
Boo :-p
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Re: Use Harpic to clean exhaust

Post by uturntony » Thu Jun 29, 2017 9:54 pm

rodyorkabr wrote:There's a product called "bar keepers friend"- it's about £4.00 & this works well in removing oxidisation safely.
It does and does it very well (thumbs)

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Re: Use Harpic to clean exhaust

Post by Gedge » Thu Jun 29, 2017 10:24 pm

To restore stainless pipes without scrubbing or scouring use by chemical reaction..amazing stuff
OptiGlanz Stainless Steel Cleaner (Removes Exhaust Pipe Bluing) - 250ml Spray Bottle

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Re: Use Harpic to clean exhaust

Post by ollydog » Fri Jun 30, 2017 6:38 am

placky2 wrote:cillit bang is bloody good on alloy,despite the knob that does the ads! (thumbs)
who our barry :laugh: :laugh:


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Re: Use Harpic to clean exhaust

Post by WIBO » Fri Jun 30, 2017 7:18 am

Boggs wrote:Don't use toilet duck,it just left me with a huge bill.



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Re: Use Harpic to clean exhaust

Post by Mikekitts81 » Wed Jun 05, 2019 9:22 pm

20190605_144907.jpg (116.2 KiB) Viewed 5812 times
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worls a treat just make sure you wash all the harpic 10 plus off as its hydrocolic acid so it will still keep eating into the metal aslong as its on toothbrush and abwipe and then anhose down is fine heres my results from a rusty exhasut that hadnt been tpuched in iver a year
20190605_153248.jpg (181.66 KiB) Viewed 5812 times
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Re: Use Harpic to clean exhaust

Post by Dansin » Wed Jun 05, 2019 10:03 pm

My 690 header before (broken) and after (welded) harpic max 10 treatment. Pretty much effortless considering the state of it.



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