Hey guys, I've know some have had this problem before and i've never paid much attention to it, but now I'm having this issue so I need all the info I can get........My bike has been running rough, valves have carboned up. I have a 2006 that I bought new in August of 07. It now has 7,400 miles on it. Only engin mods are pipes, Baron's BAK, and AIS removal. I've been running a 172.5 main jet with the needle on #3 groove with the PMS screw turned about 4 out.............I just got some different size jets today and going to try a 170 with needle on 4th groove from bottom with the PMS screw 3 turns out, I will try this tomorow.............I have already cleaned the valves out with the seafoam treatment and run the crap out of the bike before I tore into the carb. I pulled my spark plugs while I had the tank off and the rear plugs are carboned up pretty bad while the front plugs look normal Is this becouse the rear head runs so much hotter? And do you think by rejetting with the info I have given will cause the front head to run too lean and cause damage?..........Any info is welcomed here!
Thanks, Billy

Don't just toss parts in there or guess on where to set things. That's the first best advice I can give.

Since you have a BAK I'm guessing you have Mikuni jets?

Make sure the float level is good. Make sure you don't have any air leaks at the Manifold to motor, manifold to carb, and carb to BAK. Put in new plugs.

Stock pilot jet?
Put the 170 in
Put the clip in the 5th groove from the blunt end.
Set the PMS at 2 1/2 to 3 turns out.

Do the WOT. If the main checks out move the clip to the 4th groove from the blunt end and tweak the needle and PMS from there.

the man knows his stuff....

Thanks Musky, I do have the Mikuni jets..... long story about how I got my new jets, but I will condinse it down...Yesterday I was in Montgomer with my job and when I got out of my meeting I went by the Yami dealer there and talked to a lady in parts and told her what I needed. She then told me she had the jets but I needed to talk to the service department to make sure I knew what I was doing to my bike. I figured ok I will see what their take was on my problem so I walked to the service dept and waited while the tech was typing on his computer and talking on the phone, I was standing in front of his desk and when he got off the phone another person comes out of the shop and he started yaking with him, then he waited on 2 other customers that came in after me 15 minuits had passed so I told him he could shove the service department up his and I walked out. I walked a block over to the Harley Shop went to the parts counter and talked to a mechanic and they had the Mikuni jets, he gave me several sizes and they were friendly gave me great service and I also found a set of nice HD brand adjustable footpegs for an engine gaurd for $20 bucks! What is wrong with Yami dealerships!!!...............Sorry I had to vent, The only thing I miss about my old HD is the service I got from every dealership I went to was great.
I will play around with it tomorow, Will the float level couse one cylinder to run richer than the other? I can understand an airleak in the intake causing this, and I have even thought about hooking my AIS back up, don't know wether this will help it any or not, just an idea.

Don't narrow your view down to just the rear cylinder. It all works together and if one thing is wrong it affects everything else. Setting the float and checking for air leaks are both part of the jetting process.

We had a discussion about 6 months ago regarding the difference in plugs between the front and back.

If you're interested in reading the 'theories', you should be able to find it by doing a search.

Doc

Musky has you going in the right direction..
you were probably very rich on the low end with 4 turns pms, and rich on the main did not help the low end either but probably felt good up in the high range..
Leave that AIS off, backfire pain in the butt.
R* from what I have experienced like the gas right up to the point the engine gets to carboned up than you chase your tail trying to figure out what is going on..
It will take a little longer to get warmed up but once it is your R* will run the same as before without all the carbon. and your fuel eco should climb.
I get 42-45 driving heavy throttle mixed city fast highway 75mph, and 48-50 when I ride with the group or charity rides staying under 55 mph.

RoadstarB wrote:
ended up with a 170main, clip 4th grove from top with the PMS 2 1/2 out. Idle is good and runs smooth thru out the throttle ranges with no hesitation. Did the WOT test in 4th gear, the bike still accelerates when I back off and hold but it is steady not anything eratic. I have no backfireing on decel. It is running great but do you think it may be slightly lean enough to worry over?

Did you do the WOT with the clip in the 5th groove?

No Musky I did not try the 5th groove, I just researched alot of others jetting info and decided to just go ahead with the 4th. I recon I was jumping ahead, I really hate to keep pulling tank. Do you think I should go back and try the 5th groove?

Then all you did was go for a ride.