Texas X Riders

Main Area => General Discussion => Topic started by: Davesax36 on June 01, 2006, 09:29:46 PM

Title: what color is lean and what color is rich?
Post by: Davesax36 on June 01, 2006, 09:29:46 PM

so there's a big debate going on the FZ1 board cuz I answered this question. Can someone set me straight please? (no broke-back comments)

Title: Re: what color is lean and what color is rich?
Post by: cybrhick on June 01, 2006, 09:41:41 PM

Lean is near white, and rich is near black.

Title: Re: what color is lean and what color is rich?
Post by: Davesax36 on June 01, 2006, 09:44:38 PM

oh, sorry. i meant pipe coloration.

Title: Re: what color is lean and what color is rich?
Post by: j1mmyj4m on June 02, 2006, 07:18:27 AM

I thought that if it was running WAY too lean the pipes will actually get red hot under the heat shields.  Aside from that I thought the pipes just turn colored from heat in general.

Title: Re: what color is lean and what color is rich?
Post by: cybrhick on June 02, 2006, 08:22:08 AM

Blue for rick, and gold for lean I believe.

Title: Re: what color is lean and what color is rich?
Post by: Davesax36 on June 02, 2006, 10:18:30 AM

ok cuz the guys on the other board are saying that lean goes gold, then turns blue after a while. I don't know what's going on. Doesn't really matter. I'm just gonna try to clean it off and then see if it comes back.

Title: Re: what color is lean and what color is rich?
Post by: Davesax36 on June 02, 2006, 10:27:45 AM

ok. check this out.

All steel discolors as it is heated, and slightly different types of steel will color slightly differently, depending on their alloy. However, all of them follow a predictable progression. If steel is heated to the temeratures shown below and then cooled, it will take on the color shown

Here are the colors and temps for standard mild steel. Yea, I know headers are stainless, so the progression is a bit different, but you get the idea...

Colors for Tempering Mild Steel
Very pale yellow 430 degrees F 221.1 Degrees C
Light yellow 440 226.7
Pale straw-yellow 450 232.2
Straw-yellow 460 237.8
Deep straw-yellow 470 243.3
Dark yellow 480 248.9
Yellow-brown 490 254.4
Brown-yellow 500 260.0
Spotted red-brown 510 265.6
Brown-purple 520 271.1
Light purple 530 276.7
Full purple 540 282.2
Dark purple 550 287.8
Full blue 560 293.3
Dark blue 570 298.9
Very dark blue 600 315.6


Before digital thermometers, we used to use these colors to know how high we had heated a piece for heat-treating purposes.

Title: Re: what color is lean and what color is rich?
Post by: cybrhick on June 02, 2006, 11:07:00 AM

Go buy some Blue Job. It will remove most coloring.

Title: Re: what color is lean and what color is rich?
Post by: hillcountryrider on June 02, 2006, 12:39:35 PM

They should not even be trying to determine lean or rich from the exhaust pipes anyways ........ they need to look at the sparkplugs to determine this situation  ::) ::) DUH ......... ask them what a perfectly balanced fule mixture is called that should keep em busy for awhile  :) ;) ;) ;)

Title: Re: what color is lean and what color is rich?
Post by: Davesax36 on June 02, 2006, 12:59:56 PM

yeah, I know. I've only got two out of four pipes bluing on my sport bike. I just "made" my own exhaust and I don't want to screw anything up too badly right before I ride it across the country.

Title: Re: what color is lean and what color is rich?
Post by: hillcountryrider on June 02, 2006, 02:47:58 PM

based on your temp chart you would be right..... the rich running would be cooler than the leaner burning engine   O0

Title: Re: what color is lean and what color is rich?
Post by: RocknRoll on June 03, 2006, 09:33:11 AM

If lean - the discoloration extend to the baffles.  If rich, the "darkest" will be at the baffles since they ignite the unburned fuel.  If you have a crossover for scavenging the pipe carrying the most "load" will discolor first.  The other may not ever discolor.

Generally speaking.