Why is my centre header pipe changing colour - 72 GT750

[MikeH1A]

I have been putting the old girl back together after quite a few months in bits. She's looking quite nice ... but still stuff to do. Last week, I started her up after her extended sleep (months not years). Prior to dismantling things, the bike was running quite sweetly. I haven't done anything to the engine at this stage - just the cosmetics and externals. She started up easily (via the electric start) after new gas and a bit of choke. As, I haven't finished adjusting the brakes yet, the bike hasn't been for a ride. I have just had her idling in the drive to get the juices flowing again. I have done this 4 times now and just left her ilding away for 30 minutes or so each time. Today I was looking at her front on and noticed that the centre header pipe has started to change colour up by the head. It has taken on a goldy, brassy hue. The other two are still the nice shiny chrome colour (as was the centre one before).

What are your thoughts on why this pipe is changing colour and what should I do to remedy it?

Many thanks, Mike

[pearljam724]

It's normal. Every chrome motorcycle exhaust does it. Especially titanium pipes. If it bothers you. You can buy a very good chrome polish in powder or stick form. Cheaper pastes won't work so well if it has gone too long. Due to the amount of water. But, paste works fine in early stages of chrome oxidation. To do it by hand, you will have to keep after it constantly. Otherwise, you'll have to remove the exhaust and do it with a polish, soft cloth and sander if it goes too long. Both approaches will keep it shiny and new. I'd also avoid letting the bike idle for long periods. Heating and cooling of the chrome very quickly from one extreme to the next is one factor into pipes blueing. http://www.youtube.com/watch?v=ygxPQMfE70s" onclick="window.open(this.href);return false;"

[Suzsmokeyallan]

Mike do you have a good clear photo showing the colour change of the chrome versus the other pipes.