Front mudguard steel brace-Is it rusty?

[djsb 493]

Just a quick prompt for you all to maybe check if the steel brace under the front mudguard is rusty. I'm currently de-rusting mine and I'll repaint it with hammerite smooth next weekend. It's open to all the rain,and grit etc from the road and I've found that almost all the paint has been removed and the surface has started to rust. Just thought I'd remind everyone.

[Guest aldmannie]

Has anyone worked out how to stop the exhaust header turning orange at the slightest hint of drizzle, or have a good suggestion for how to clean it up...?

Every used NC I've seen has had rusty pipe syndrome.

[Mike5100 2,061]

36 minutes ago, djsb said:

Just a quick prompt for you all to maybe check if the steel brace under the front mudguard is rusty. I'm currently de-rusting mine and I'll repaint it with hammerite smooth next weekend. It's open to all the rain,and grit etc from the road and I've found that almost all the paint has been removed and the surface has started to rust. Just thought I'd remind everyone.

I painted mine on my first NC with Hammerite but i don't think it made much difference.  The environment for that bit is about as harsh as you could possibly get - a high pressure jet of salt water with grit in it.  It might have been better as some kind of composite material.

Mike

[Rasky 8]

Sorry but in my opinion hamerite or smoothrite is no good in this situation, it chips to easily. OK for garden gates. Good product available on that auction site from Frost auto products, called POR 15. 

Edited October 23, 2016 by Rasky
Wrong information.

[embee 7,288]

3 hours ago, aldmannie said:

Has anyone worked out how to stop the exhaust header turning orange at the slightest hint of drizzle, or have a good suggestion for how to clean it up...?

Every used NC I've seen has had rusty pipe syndrome.

Solvol Autosol is about the best stuff for polishing it, but it'll go brown again fairly soon. Unfortunately that's what the material does. The term "stainless" is not strictly correct, it is corrosion resistant steel. The surface will discolour when heated.

[djsb 493]

4 hours ago, Rasky said:

Sorry but in my opinion hamerite or smoothrite is no good in this situation, it chips to easily. OK for garden gates. Good product available on that auction site from Frost auto products, called POR 15. 

It's not rusty enough to use POR15. I'm just going to make do with hamerite for the time being.

[Guest aldmannie]

5 hours ago, embee said:

The term "stainless" is not strictly correct, it is corrosion resistant steel. The surface will discolour when heated.

 

Ah yes, the meaning of "stainless", less stain rather than stain free.

There seems to be quite a bit of variation in the metallurgy of "stainless" headers, some definitely stain less than others.

Maybe the NC header is more prone to staining because it contains the cat and gets really hot...?

Looking at the price of the thing it should be the bestest super-douperest stainless money can buy, and have you seen the price of the oxygen sensor which mounts in it?

£931 for the header and £296 for the sensor. Ouch.

[embee 7,288]

1 hour ago, aldmannie said:

 

Ah yes, the meaning of "stainless", less stain rather than stain free.

There seems to be quite a bit of variation in the metallurgy of "stainless" headers, some definitely stain less than others.

Maybe the NC header is more prone to staining because it contains the cat and gets really hot...?

Looking at the price of the thing it should be the bestest super-douperest stainless money can buy, and have you seen the price of the oxygen sensor which mounts in it?

£931 for the header and £296 for the sensor. Ouch.

It's also thin section material, to keep weight and cost down but also to minimise the thermal mass and aid fast warm-up of the cat. Unfortunately this means the outside surface runs nearer the temp of the inside than if it was thicker material (temperature gradient). This article http://www.bssa.org.uk/topics.php?article=140 gives a nice simple description, suggesting the brown we see is typically around 400C, which is about what I'd expect for the outer skin in free air. Catalyst light-up temp is around 300C so that's a minimum you'd expect, and exhaust gas at full power will be in the parish of 850C typically.

[Guest aldmannie]

Interesting stuff, cheers for that

 

Rusty header has to be one of the NC's worst features, I've seen them almst new with about a thousand miles on the clock that look two years old.

 

Does a fender extender make any appreciable difference?

[outrunner 4,457]

1 hour ago, aldmannie said:

Interesting stuff, cheers for that

Does a fender extender make any appreciable difference?

Not that I can see, my NCX bought new in june and fitted with a fender extender has a discoloured front pipe after 5500 miles.

 

 

Andy.

[Rednc750se 171]

Usually any motorcycle exhausts discolour due to the heat, I do not mind that as long they do not develop leaks.

[michael 324]

i'm with most folks. Occasionally i'll look there and think to myself, "well i've seen better looking exhausts," but heat sourced discolouration is a natural outcome. Some manufacturers used to use double wall pipes, other's cover pipes with "heat shields."

 

Either way, it can't be seen from my seated position, it doesn't adversely affect my comfort or the functioning of the motorcycle so i've relegated it to an area in my brain that also stores my wife's propensity to re-arrange furniture, buy flowers or concern myself with the colour of the towels in the bathroom.

 

Now what *will* drive me nuts is all the places on a motorcycle that require lubrication, grease and cleanliness that I don't get to often enough.

[Guest Mac750]

I once saw a post on a classic car forum where they used Brasso and painted it on the exhaust manifold. When it got hot it turned white. Never tried it so cannot say if it works.

Seen exhaust wrap used on headers BMW /Triumph etc. But I think it looks messy and would it ignite on a hot cat ???. The only visual aspect of the 750x I don't like is the tacky grey /black  exhaust cover at the front of the engine, but  that's just me .