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what paint to prevent corrosion ?


Mike5100

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Mike5100

There's an x-shaped bracket under the NC's mudguard which on your bike will already be red rusty.  I know it doesn't really matter because it's out of sight, but if I want to 'paint' something like that what is the best way of doing it.  Is it better to get it powder coated or painted traditionally with primer undercoat and topcoat, or even simply painting over the rust with hammerite.  Until last year I would have always plumped for powder coating but then I read that it can crack at stress points, and also powder coating is quite a thick coat so how do you deal with the bolt holes.

And a second unconnected question.  why are our brake banjo's coated in something that does not resist salt and in no time at all gets a white fur on it?  Well that's a rhetorical question really, because I would actually like to know if you think painting all the banjos with black hammerite would prevent this and if so what would be the best way of prepping them and doing it?

Thanks

Mike

 

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Personally I'd rub down the X-bracket with scotchbrite (scouring pad) and some sort of lubricant, I tend to use sugar soap solution on stuff I intend to paint. Rinse off and dry. Then spray with aerosol etch primer and a suitable top coat. Being where it is it is likely to need doing every now and then, it's getting sand blasted all the time with salty crud etc.   I find etch primer helps stop paint peeling even if it gets damaged and develops rust spots.

 

Simplest is probably just a coat of Hammerite. Plug the threads with a piece of rag etc.

 

The most durable stuff I've ever come across is a brush-on high build phosphate primer (like red oxide but a bit better for corrosion prevention especially on already rusty steel), then an aerosol top coat. This is quite thick stuff when brushed on, but it works brilliantly. Not the best for cosmetic purposes but you can't see that bracket. I have the remnants of a 2.5L tin of the high build primer which I used on some 5-bar farm gates but it's beginning to get a bit lumpy now, though I still use it on all sorts of steel bits and brackets etc  which I fabricate and which are going to live outside.

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Guest bonekicker

If you keep all these brkts and the rest of bike covered in oil or WD40 it won't rust-- it takes a little time but far less than taking parts off rubbing down/priming/painting/refit.  :ermm:

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3 hours ago, bonekicker said:

If you keep all these brkts and the rest of bike covered in oil or WD40 it won't rust-- it takes a little time but far less than taking parts off rubbing down/priming/painting/refit.  :ermm:

 

Mmmm, WD40 on a front tyre. Sounds like fun 😋

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3 minutes ago, CFB said:

 

Mmmm, WD40 on a front tyre. Sounds like fun 😋

 

:D 

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Guest machinman

Bit of waxoyl, acf etc on a cloth, wipe it on and forget.

Ive done the forks ( the piece inbetween the two yokes and the brake pipe brackets.

Pointless painting them imo.

Keep them lubed.

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Mike5100

these bits have been liberally coated in acf50 very regularly, Michael, but as Murray says they sit in a powerwash stream loaded with sand.  Any acf50, wd40, or xcp is gone in the first salt laden winter ride.

Although I did have rusty front mudguard brackets on ALL 3 of my NC bikes.  My issues now are with my Rocket3 and my Africa Twin.  But I posted on here because I knew I would get much better advice than on either the africa twin forum or the rocket forum.

Thanks Murray I will do a search for that phosphate high build primer - is that instead of the etch primer or as well as?  I will also get the parts (the R3's rear mudguard frame and silencer hang brackets) professionally grit blasted to get old paint off and as much rust as possible.  Then I will use your priming system, then I will take them to a paint shop for topcoat as I would make a complete mess of it.  Now the thing with the bolt holes - I know that powder coaters put bolts and nuts through holes that you don't want to close up - but surely that leaves uncoated the very points where rust will start?

I'm still interested in people's opinions on hammeriting the banjo's.  In previous years I have painted them with acf5 evry other ride or so but this year I decided to try a single start of season coat of xcp.  It hasn't worked and after two rides the front banjos on the Africa Twin are white and furry.  It's not so bad that I can't get them looking ok by vigorous rubbing and fresh application of acf50, but once the white crust appears you can see that the surface coat is damaged - so why don't maufacturers use painted ones (or ideally stainless steel like those on the Rocket which are still perfect after 6 years).  I could get stainless aftermarket pipes and banjos fitted but apart from the expense, the insurance company regards these as performance enhancements).  So if there's a paint coating that might work what is it, and is there a way of painting them so it doesn't look like my 3 year old grand-daughter has done it?

Mike

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Guest machinman

Your over analysing Mike, paint them by all means, but i think youll be disappointed in the long term

It sounds like you look after your bikes and regularly maintain, id still use a wet oil etc and inspect regularly.

As soon as paint chips and salt gets in.....i think you know the rest.

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Spindizzy

If its a bracket you can't see, just use car underseal. Its impact resistant and designed for use in cruddy non visible areas. Same stuff they use in wheel arches and under car body. 

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MikeBike
10 hours ago, embee said:

Personally I'd rub down the X-bracket with scotchbrite (scouring pad) and some sort of lubricant, I tend to use sugar soap solution on stuff I intend to paint. Rinse off and dry.

I now use Bar Keeper's friend after discovering it recommended in a sailing mgazine for removing the yellow discoloration on GRP that lost of other products didn't shift. It's stated on the pot as being a rust remover and there are several examples of peoples success online. e.g. http://vintagecrank.com/bar-keepers-friend-works/

and I've found that it works well.

 

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Mike, I don't think I would paint the banjos myself. But I can absolutely see why you're tempted. Bloody things. Always the very first things to show signs of distress. And almost impossible to 'bring back' once they've corroded. How about a smear of grease? A pal who rode a 750 Suzuki all year round used to cover the whole thing (you know what I mean!) with grease. Come springtime he would clean it all off and it was like new underneath.

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4 hours ago, Mike5100 said:

........ I will do a search for that phosphate high build primer - is that instead of the etch primer or as well as?  ......

Either/or. The etch primer I use after having it recommended is U-Pol Acid8 etch primer https://www.amazon.co.uk/U-Pol-ACID-Acid-Etch-Primer/dp/B006HFM5YG/ref=sr_1_1?ie=UTF8&qid=1512566843&sr=8-1&keywords=acid+8 , it's expensive stuff but I only use it where justified i.e. exposed to the elements, otherwise interior use bits get a regular aerosol primer. I think I got the Acid8 from https://www.eurocarparts.com/ but they don't list it now, just an Isopon anti-rust primer (it may be very similar?), note the discount codes for Eurocarparts, usually 25-30% so makes it more sensible. They are good for other general purpose aerosol paints. As someone else suggested, maybe use a "stone chip" aerosol for a top coat?

The high build phosphate primer I have is "Johnstones quick dry zinc phosphate primer - red oxide"  https://www.decoratingwarehouse.co.uk/johnstones-quick-dry-zinc-phosphate-primer  which I got from a local industrial supplies place (Astleys in Coventry), not sure if it comes in smaller can sizes, I'd imagine so. You need paint thinners (xylene type stuff) for it, not white spirit. Don't be tempted by Screwfix no-nonsense red oxide primer, it's very poor in comparison.

Edited by embee
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Mike5100

Many thanks folks - some good info there.  Simon the banjos are so exposed to the salt laden jet that I suspect any grease covering would be gone in no time.  I think I will give the charcoal coloured original planished finish hammerite a go - the end appearance canot be too far from the original colour, and it doesn;t show brush strokes - and it's supposed to be more flexible that ordinary paint because of the fibreglass - IIRC.

I will take some photos.

Mike

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31 minutes ago, Mike5100 said:

I will take some photos.

Mike

 

Look forward to ‘em. :) 

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Grumpy old man

I just coat the banjos and other nut heads and stuff with a daub of copper grease seems to stay on while riding even under the power washer but easy to remove witha cloth and I think the copper effect looks good😊

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Rev Ken
8 hours ago, Mike5100 said:

these bits have been liberally coated in acf50 very regularly, Michael, but as Murray says they sit in a powerwash stream loaded with sand.  Any acf50, wd40, or xcp is gone in the first salt laden winter ride.

Although I did have rusty front mudguard brackets on ALL 3 of my NC bikes.  My issues now are with my Rocket3 and my Africa Twin.  But I posted on here because I knew I would get much better advice than on either the africa twin forum or the rocket forum.

Thanks Murray I will do a search for that phosphate high build primer - is that instead of the etch primer or as well as?  I will also get the parts (the R3's rear mudguard frame and silencer hang brackets) professionally grit blasted to get old paint off and as much rust as possible.  Then I will use your priming system, then I will take them to a paint shop for topcoat as I would make a complete mess of it.  Now the thing with the bolt holes - I know that powder coaters put bolts and nuts through holes that you don't want to close up - but surely that leaves uncoated the very points where rust will start?

I'm still interested in people's opinions on hammeriting the banjo's.  In previous years I have painted them with acf5 evry other ride or so but this year I decided to try a single start of season coat of xcp.  It hasn't worked and after two rides the front banjos on the Africa Twin are white and furry.  It's not so bad that I can't get them looking ok by vigorous rubbing and fresh application of acf50, but once the white crust appears you can see that the surface coat is damaged - so why don't maufacturers use painted ones (or ideally stainless steel like those on the Rocket which are still perfect after 6 years).  I could get stainless aftermarket pipes and banjos fitted but apart from the expense, the insurance company regards these as performance enhancements).  So if there's a paint coating that might work what is it, and is there a way of painting them so it doesn't look like my 3 year old grand-daughter has done it?

Mike

Ridiculous! It is an added (marginal) safety feature. Some insurance companies charge for the most minor modifications that have no bearing on increasing performance. Fortunately mine doesn't and have approved even uprated suspension which could be argued as performance enhancing, but at least it meant I could get around corners...... :D:D

Edited by Rev Ken
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Rocker66
8 hours ago, Spindizzy said:

If its a bracket you can't see, just use car underseal. Its impact resistant and designed for use in cruddy non visible areas. Same stuff they use in wheel arches and under car body. 

Back in the days when most mudguards were chrome I always used to use underseal on them.

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I painted mine with about 3 coats of POR15.  I bought a small starter kit that included the POR15 cleaner/degreaser fluid,POR15 metal prep rust remover and a small tin of POR15. I used a small syringe to decant some of the paint into a small glass jar and sealed the tin with a layer of cling film to stop the lid from sealing permanently. It dried to a nice tough finish. and. Not tested properly yet but hopefully will last a while.

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Guest bonekicker

But surely the whole point of maintenance is maintaining--that means when you wash the bike--let it dry and reapply--whatever you choose to the metal parts each time--not oil it once in a blue moon:BangHead:

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Mike5100
1 hour ago, bonekicker said:

But surely the whole point of maintenance is maintaining--that means when you wash the bike--let it dry and reapply--whatever you choose to the metal parts each time--not oil it once in a blue moon:BangHead:

While it's true that reapplying acf50 or grease to the banjos would take only 5 or 6minutes after each ride, there are a ton of things that you could do after every ride that would probably keep your bike in good nick, but when all added together it becomes impractical for those of us who ride two or three times a week through the winter - or indeed commute.  A very good paint coating such as on the NC wheels needs no attention right through a winter so if the banjos could be similarly painted neither would they.

I'm trying to work it so that all I have to do is follow the Honda user manual which (I think) says rinse the bike down with fresh cold water.  (Actually I have just looked up the Africa Twin guidance and its more onerous.  A complete thorough wash and dry of the whole bike after every ride in salty conditions, including relubricating all moving parts especially the chain. (and don't use a power washer)  That's about an hour for me even with the airblaster dryer, and I ain't going to do that standing in a typical north east storm in winter.  

My chain is really suffering so I'm going to have to think that one through but if I can paint vulnerable bits so that a rinse and blow dry works then that's the aim.

Mike

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Graham NZ
22 hours ago, Spindizzy said:

If its a bracket you can't see, just use car underseal. Its impact resistant and designed for use in cruddy non visible areas. Same stuff they use in wheel arches and under car body. 

 

Bull's eye IMHO.

 

A problem with all paint systems on cheaply produced brackets etc. is that they have sharp edges which the paint drains back from, leaving only a very thin coating which is prone to failure.  On well produced brackets the edges are rounded by rumbling.  Take a look at the bits on new Harleys.  Only high-build coatings have any chance of longevity over sharp edges.

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Graham - are you saying Harley bracket edges are rounded or not rounded?  I'm curious.

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Rev Ken

I don't wash down my car after every drive, and that goes for my bike! In the 'good old days' there was no problem as our bikes had a generous coating of oil, with any excess caught in a drip tray. The best I can do to-day is to get an annual treatment by an organisation that fully valets my bike and then applies various agents to offer some protection. Unfortunately the local lad has given up so must look for an alternative.

 

My bike is well maintained, is always well shod (I never run tyres right down to the end of their legal lives) and I give it a wash and brush up when it really needs it, but have better things to do than spending hours keeping it looking 'as new'. Those of you who do have my respect and I would buy your bikes in preference to mine, but I think mine would also sell as an honest bike kept in excellent working order.

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Guest machinman
1 hour ago, Mike5100 said:

While it's true that reapplying acf50 or grease to the banjos would take only 5 or 6minutes after each ride, there are a ton of things that you could do after every ride that would probably keep your bike in good nick, but when all added together it becomes impractical for those of us who ride two or three times a week through the winter - or indeed commute.  A very good paint coating such as on the NC wheels needs no attention right through a winter so if the banjos could be similarly painted neither would they.

I'm trying to work it so that all I have to do is follow the Honda user manual which (I think) says rinse the bike down with fresh cold water.  (Actually I have just looked up the Africa Twin guidance and its more onerous.  A complete thorough wash and dry of the whole bike after every ride in salty conditions, including relubricating all moving parts especially the chain. (and don't use a power washer)  That's about an hour for me even with the airblaster dryer, and I ain't going to do that standing in a typical north east storm in winter.  

My chain is really suffering so I'm going to have to think that one through but if I can paint vulnerable bits so that a rinse and blow dry works then that's the aim.

Mike

Throw the user manual in the bin. They are not written for the UK. 

Probably ok to hose down if you live in southern California where it rains for 10 minutes every other year.

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