PDA

View Full Version : Lean it out or Richen it up


Regulator 250X
05-11-2002, 11:39 AM
Last night i just got done putting a new exhaust on my 250x. It is stock bore and nothing done to the engine. I have an oversized Graydon headpipe welded up to a Supertrapp 4 inch race silencer. I rode it for awhile and man did that header and can add mid and top end. My buddy, who is going to school to be a motorcycle mechanic told me to lean it out after he looked at the plug. I always thought that once you let something breath more you should up the gas to up the performance? the stock jet was a 125, and i put a 122 in it. What are your guys' thoughts? i was running the air box lid when i had the 125 in it. now its off. Help!
flaneledholes
05-11-2002, 11:56 AM
He is wrong richen it up no matter what he says. With the airbox off and the pipe you are runnin lean.
nakomis0
05-11-2002, 12:46 PM
Better just look at the plug, it its black than he could be right, the bike could have been jetted rich before the pipe was even put on.
deansfastway
05-14-2002, 10:02 AM
HOW DOES IT RUN BETTER ,WITH THE LID OR NOT? YOU CAN USE DUCT TAPE TO RESTRICT THE AIR OPENING TO FOOL THE ENGINE INTO BEING RICHER IF IT RUNS BETTER THEN YOU ARE TOO LEAN , ALMOST ANYTIME YOU PUT ON A BIGGER HEADPIPE YOU SHOULD PROBABLY GO RICHER. FASTWAY MOTORSPORTS
oynot400
05-14-2002, 10:34 AM
I have a couple of buddies that when they put on there filter and pipes it read rich to them. I quesion it though, you should check it with a new spark plug to get a more accurate reading.
Where are you at in Northern Iowa? :confused:
deansfastway
05-14-2002, 10:41 AM
WERE IN NEW JERSEY. ITS REAL HARD TO READ PLUGS , I HAVE BEEN DOING THIS FOR 20 YEARS AND STILL LIKE TO USE THE SEAT OF THE PANTS OR ENGINE FEEL METHOD BEST.
Regulator 250X
05-16-2002, 05:01 PM
Hey sorry guys for not getting back to you right away, i just had my tonsils out this week. You would think a 20 year old guy would have had them out by now right? Stupid me! anyway, I put the 122 in and ran it without the lid. Man was there a dead spot without the lid. So i put that back on and it runs great. I still might try putting a 125 or 128 just to see what happens. I rode it around enough to get some marks on the plug and yeah it was rich. So he was right, actually i think i will go out and ride it some more and check it again just to be sure.

This is for the guy from Iowa. Im about a half hour northeast of Mason City! Thanks for all your help!