Discoloration in chrome means heat, not rich or lean. First they turn yellow and then if they get even hotter they start to turn gold to an ever deeper blue.
Where they turn color can give you an "indication" on wether the bike is rich or lean and to what degree.
Generally speaking a pipe discoloring much near the header pipe flange at the head means lean and if it happens further back in the canister it means rich or afterburning due to reversion or an air leak in the pipe. It is also going to discolor at a spot where there is a restriction in the system even if the bike is jetted right, like for example the collector of a 2 into 1. Engines with cams that have a lot of overlap or with too late ignition timing will discolor the header pipe even if the fuel mixture is spot on
No matter what you do they are always going to discolor slightly unless they have some sort of internal thermal coating or if they are ridden extremely hard for a period of time. It's not a science, more of a judgement call you make observing and listening to the bike in question.
When you put pipes on you have to wipe them down with alcohol and then heat cycle them a couple of times. Any oil or fingerprints on the pipe will burn in first time you start the bike.
Where they turn color can give you an "indication" on wether the bike is rich or lean and to what degree.
Generally speaking a pipe discoloring much near the header pipe flange at the head means lean and if it happens further back in the canister it means rich or afterburning due to reversion or an air leak in the pipe. It is also going to discolor at a spot where there is a restriction in the system even if the bike is jetted right, like for example the collector of a 2 into 1. Engines with cams that have a lot of overlap or with too late ignition timing will discolor the header pipe even if the fuel mixture is spot on
No matter what you do they are always going to discolor slightly unless they have some sort of internal thermal coating or if they are ridden extremely hard for a period of time. It's not a science, more of a judgement call you make observing and listening to the bike in question.
When you put pipes on you have to wipe them down with alcohol and then heat cycle them a couple of times. Any oil or fingerprints on the pipe will burn in first time you start the bike.