Ok Finally got around to removing my AIS. During the prcess I found a few other issues, Cracked intake manifold, which I was pretty sure I had anyway. But I didn't have a new manifold so i sealed the cracks in this one till this winter when I can afford a new one. Got the AIs removed no problem. Plugs went in great but now the bike is running rich as hell. Black smoke on idle and big puff when you rev it. Runs pretty decent once you are up to speed surprisingly. No backfire on decel that I could tell. PMS all the way in and still rich. SO I guess I am asking where to start getting her back in line. She ran great before. I have a cobra jet kit, It was cheap . LOL

So i am guessing I need a new setup.

Stock 2003 Roadstar 1600 Cobra Slashcut headers with baffles removed. Hypercharger. Stock manifold (cracks sealed with special stuff) What should I check on this setup.

Woody

if all you did was to remove AIS and you did it right, there is no need to rejet carb.
the hose that connects to the top of the new intake manifold, you cap that off when you removed AIS?
You sure you sealed the new intake good?
new gaskets?
Just because intake had cracks in it does not mean it leaked. Mine looked like the grand canyan but did'nt leak.
what carb jets do you have now?

Im sure the vac port was sealed. I have a hypercharger, so it was just a mater of removing the hose from the T and putting the plug on. My fear is the PO rejetted for a leaking intake and possible leaks in the AIS as well? There was obviously more air getting into the motor prior to the AIS removal so now I need to compensate by rejetting. If the PMS is all teh way in then I dont have a choice.

All I know now is it is running ungodly rich, and just looking for a starting point.

Woody

just did a little test that confirmed my suspicions. tokk the hypercharger off, started her up and left the vaccuum line open and she ran less rich Plug it with your finger and it goes back to black smoke. SO I am guessing the PO did tune to a leaking intake or AIS the hoses on the AIS were not great.

Woody

AIS only puts fresh air in AFTER the exhaust valves. It does not affect the combustion mix. When removed, it also does not affect the combustion mix. Just make sure the vacuum port that went to it is sealed off.

The Hypercharger setup changes the whole jetting on the carb. Under the black cap on top is a tiny air jet under the slide diaphragm that the change along with a big slide needle and huge main jet. You need to start buy putting the air jet back to stock check the pilot jet size stock is 35. Get some idea of what main jet you have first. If in doubt change the intake manifold too as you are already in there with the carb off. Not sure about your jet kit you have so if it has instructions follow them and you may have to replace the slide needle in which case you will have to get a get a jet kit with on.

Thanks Curt,

I have cobra Jet kit with the slide needle. where it is gonna get confusing for me is figuring out the diff between the jets that are in the carb and the number on the Cobra kit. Not sure which jet to start with. It has 160,165,170 and 175 in the kit with one slide and clips etc. the bike is not too far off, just pretty rich. runs great on the highway. But when you let off it is like it is loaded up and running on, prob too much fuel. it settles down in a few seconds.

Woody

Under normal circumstances you are correct, but out of curiosity I put a vacuum pump on the AIS valve, and pumped it up. it wouldn't hold. So it was leaking inside, allowing more air mix into the intake, causing a lean condition, So I assume the PO went to a bigger jet trying to compensate for that. Also if the intake was leaking. I really have no way of knowing now, since I broke my own rule and changed 2 things at once, but that would explain why he had so much trouble jetting the bike. So now I need to find a new starting point and rejet accordingly.

Woody

OK So I decided to go with the cobra/dynojet kit, since I have it and rejet. I pull the carb apart and it has an 187.5M mikuni jet in it. According to the chart thats a 200 Dynajet, wholly smokes. I drop in a 165 Dyna jet and set the pms to 2 1/2 turns. I swapped the new slide in too, but it looked exactly like the dynajet slide I replaced it with miked the same on both ends. Put her back together and boom. No more smoke, Idles like a dream, made a few adjustments to pms. runs and accelerates nice. adjusting PMS now it does everything the tech articles say it should.

I have some fine tuning to do. When I get on it real hard off the line (rev limiter hard), and let off it back fires pretty solid. But only when I really get on it. It also seems like it should have a little more on the top. 85-90 it starts tapering off pretty fast.

But it just confirmed they were tuning to an air leak carb system. Or they had a Dynajet slide with a mikuni jet. Not sure how that would mess things up.

It has a 165 pilot jet, not sure if I should change it for some of it.

Thanks everyone for your input and help. It always gets me going when I listen to all of your ideas and Helps me get off the couch and go fix it.

Woody

The 165 DJ main, is way small. Look at the chart. The stock 99-03's, use a 165 Mikuni main, and it is lean for anything but bone stock. The 165 DJ, is somewhere in the 150's compared to Mikuni jets. Thats why you have no top end.

Do you mean a 35 pilot?

Your backfire problem is probably the pipes.