Bonneville America Forums Forums Technical Forums Performance Mods black plugs

ok here we go again...recently removed ai...rejeted to 132 and 42s...shorty pipes....snorkels out...k&n single...3 turns out....Here is the dilema...cant seem to brown up the plugs...mind you i have only been around town and havent had it out for a good cruise...thats until monday going for 2 weeks....any ideas...should it clean itself up afte rrunning it at highway speed? seems to back fire when starting because of carbon...any help would be appreciated...I tried 2 and 1/2 turns but got popping on decel.....cmon folks i need some ideas...pls

What's your elevation?
Maybe you should back down to a 125 main and give that a shot.

just checked it out 1443 ft...

You should take a pic of the plug I have a uni filter, AI removed, and little drag pipes. My plugs are a little white but probably just as lean as it comes from the factory. No back-fireing at all.

Hey Mike,

You might want to try a set of new plugs and start from there.

How new is the K&N filter. How much oil is in it?

Sounds like your set up is fine though. Not sure why the plugs might be a bit black. They should clear up on the highway.

Let me know when you pass through on your way back. Java at the local Tim Hortons Angels hangout

PS - Watch out for bears. Saw 2 on the highway from Sudbury today.

Some popping on decel is actually a sign the bike is set up right so you might go back an 1/8th turn at a time until you're happy. Your elevation really isn't high enough to play into it as I routinely go from 900 to 2000 ft on a daily drive without drama. Now, when you say the plugs are black is this the insulator (where you're meant to be checking) or the base of the plug (which will blacken at tickover and not clean itself for many miles)?

Ya right on greg picked up a new pair today,going to give it a shot,ottawa is a long way I will have lots of time to tinker.Seen a few bear out down your way also with a side order of moose.And they wonder why our pipes are loud and i dont run it at night.....M

I had a set of the TORs on my 865 Speedmaster.I was running 42 pilot jets at first,ended up going back to the 40 pilot jet.Since then I have installed different mufflers and the dual K&Ns so now I have the 42 pilot jets with 150 mains.I like many others have tried several set ups and sometimes smaller is better.With the 42s in it I had the idle mixture screws screwed way in.Then I switched it to the 40 pilot jet and ended up screwing them back out.Good luck.Also try the new plugs after the rejet.

There is another current thread on decel popping. Keep in mind that if you have more open (less restrictive) pipes, some decel popping is normal. If you adjust the pilot screws out to eliminate all of it, you will be running too rich. Turn the screw back in a bit until you do have some decel popping. Put some miles on and then check the plugs. As Ed (OldRoadie) said above you should make changes about 1/8 turn at a time.