I purchased a set of new in the box SE slipons from ebay awhile back. The starting bid was $99.95. I was the only bidder!!!! I put them on and installed a new K&N filter . I haven't been able to ride it much but have checked the spark plug and it still black. Should I install new plugs and check it again?

Thanks in advance 2007 XL883C

 

Yes. If you did not re-jet you are most likely running lean. Put some plugs in it and run it hard, them check 'em. With all the additives in today's gas, it's harder to read them then it used to be, but still gives you a ballpark idea.

If the K&N is in your stock housing you may be border-line for a full jetting. I found that with my SE II's and a modified stock airbox I got the best performance from adjusting the idle mix and changing just the main jet. Get the full jet kit for less than $10 and then you can try it for yourself.

This guy is a good place to look for jets at a reasonable price:
www.sorgys.com

He always has them listed on ebay too.

 

If you've changed both pipes and AC you need to remap, PCIII or SERT to change your FI settings which are too lean. From what I've heard the FI will only compensate for slipons but not the combinataion of the two without being lean. Of course I'm a carb guy so what do I know about FI on the 07s.

 

If the plugs are black, the bike is to rich! not lean. To lean they would be white.

I agree if you changed the A/c and pipes, you need a remap. Alot of guys just go to a race tuner. I ended up getting the thunder max EFI W/auto tune. very nice piece and I can make any adjustments myself with no added cost's.

 

I was just gonna say the same thing.Everyones talkin' lean when the poster stated his plugs were "still black" and black is not always bad but it'sdefinately not lean.It usaually indicates a rich condition but..... it depends on how black and exactley what is black.Is the porcelian black or just the threads? You're always gonna have some carbon on your plugs.Or a least you should

 

Also... you can't just run the bike and check your plugs,you wont get an accurate reading like that.The best way to get an idea of how the bike is running under normal conditions is to run it steady at 55-60mph for a few miles.When there is a safe place to pull over, pull inthe clutch and shut the bike off(@55mph)and coast to a stop.Have a smoke or a coffee and let the bike cool a little and then pull the plugs to check them and that will give you a good idea on fuel mix under normal running conditions.

 

I liketo smella littleraw gas If I don't smell it comming out the Mufflers Im running to lean

 

What I was getting at was this...

My orignial plugs were black from choking and running slightly rich. When I opened up the intake side the mixture starting running lean. You could not tell by looking at the plugs because the black soot was still there (i.e. it does not burn off completely). Since he has made the mods, I'm willing to bet he is lean but the plugs are still black from before the changes. I suggested putting in new plugs and checking again. At that point, I don't think they will be black at all. Most likely he'll see the white stripe on the electrode indicating lean.

 

I had not changed the plugs and they were still black . I will put new plugs in and check again as suggested. thanks for all your help. I will let you know what I find when I can get out to ride. It is 25 degrees here in southern Idaho today. It might be a little while . thanks again

 

Best way Ive heard to check the plugs, which is what I did on my carb model, is to put in a new set. Then go to a clear stretch of highway, and run full out for about a mile to mile and a half, full throttle as hard as you can within limits. Slow down some, then do an engine cutoff and safely coast and get pulled over to the side and pull out your plugs and see what they look like. White electrode tip too lean, black too rich, gold just right.