I moved from Bend Oregon elevation 3500' to Hot Springs Arkansas elevation about 600, and my bike is coughing and sputtering so I pulled a plug thinking it is running rich but they look like it is running lean they are grey, anyone got any suggestions, Thanks
And it has a carb

 

Carb or FI?

 

Are you sure you didn't get a tank of bad gas? That small of a change in elevation shouldn't really have any effect.

 

It was probably jetted for the higher elevation. I would look into at least getting the carb checked if not get it rejetted.

I know I suck at math, but how is going down 2,900 feet lower in elevation a small change?

 

It's not much difference as far as his carb should be concerned. Elevation where I live is around 1,200 ft and my carb is jetted to run it's best at that, however I go from 700 ft - 6,000 (Smokies) on a pretty regular basis without any issues at all. One of my bikes I travel on has a mikuni the other has a cv carb. I have even crossed the Continental Divide several times without a problem. I've lived places where it's not unusual to change 3,000 ft in a half hours time in normal riding, many people on here do it daily on their commutes. I'm not saying his fuel mileage or peak performance might not benefit from from rejetting but it shouldn't be spitting and sputtering from that small of a change. jmo

 

Ok, I've never understood all that elevation stuff. When you look at the numbers, 2,900 feet seems like a lot. I guess with elevation, not so much.

 

I live at sea level, have a carb, and routinely ride in the Sierras crossing mountain passes between 9,000 and 10,000 feet with no issues. Spitting and sputtering could be due to a clogged fuel filter on the petcock and inside the gas tank.

 

Here in Colorado I can do a 7,000 ft. change in elevation in 2 hours!

 

I live in Texas where everything is flat, so I've never experienced that lol

 

To the OP, might give some more details and someone might be able to help. Did it start doing this right after the move? After a fill-up? Have any problems before? Gray colored plugs might not be a bad thing, a tannish-gray color is what they should look like in normal conditions. I would start by making sure there is water free gas in it and next check the filter. If there isn't a problem there I would suspect some dirt/junk in the carb.