First, let me thank all of you in this forum.  With out the insight here, I never would have had the courage to work on the bike (2005 S40) myself.  I wish I had more to offer but before this I never even changed my own oil (Well once...).  So here's my issue.  I did the white spacer mod and put in a 152.5 main jet for a Jardine muffler.  It ran good except for a little sluggishness at approx 1/8 throttle.  So this year I added a #55 pilot jet.  Since then problems.  I can start it up but after less then a mile the bike dies.  I replaced the battery but same prob.  I took it all apart again and found this...




Before I put it back together, with a new hose, could this be the issue?  Should I be looking further?  Any suggestions would be helpful.  Thanks again.

That sucks.  Yes it is the vacuum line.  I cut the "holes" out and was going to re-connect it.  I've made all the adjustments, according to lancers guide I could but I still had the same problem.  Oh yeah, it also happened with the pettything set to prime.  I had a nice smell of gas from the airbox and the vent tubes when I took it apart.  Could the #55 pilot be too much?  The pilot screw was two turns out before I switched.

Thanks for your help guys.  Same problem though.  I get her started, then, about 1/4 mile out she sputters and dies.  There was a bit of backfire as well.  When I took it apart there was a moderately strong smell of gas from both the air box and bowl vent tubes.  Does this indicate anything to either of you?  I read an earlier post that got me thinking....  Could any of this be caused by the float level?  I tried to set up the "water level" trick to see if they're at the right levels but was unsuccessful so far.  Anyway, thanks again.

Ok, now the pictures showed up The pipes goes further into the rubber hose than those marks,  so I think that is not the issue.
It came to my mind - what airfiltermods have you made ???

Ok.  I had the tank off anyway, thinking there might be a leak in the rubber gasket surrounding the slide.  There wasn't, but that's when I found the prob with the vac line.  I do have the pettything off but I was afraid to take it apart.  The beast came with a #52.5 pilot, 2.5 turns out on the pilot screw.  I've added the Jardine muffler and it felt sluggish at 1/8-1/4 throttle, still 2.5 turns on the pilot screw, so I bumped it to #55.  Since then I haven't ridden five miles.  Just sputters and dies.  It'll idle for awhile but all the time just begging to die.  I have to adjust the pilot screw (turning out) to keep it going.  Just pulled the plug.  Extremely sooty, black as a hockey puck.  How long does it take a rich condition to change the plug color?  Could I have been rich before?  Considering the pilot screw adjustment, I believed I might be a little lean still.  Anyway, I will be taking the bowl off as soon as possible.  Any suggestions as to what/ how to inspect/ adjust the float level?  I still haven't mastered the water level trick.  

Thanks again for your help.

Look for the floats to be basically parallel with the top of the bowl at full stop.   Check the needle/seat for grit with a q-tip coated in carb cleaner, and float bodies for leaks while your in there.  But, my money is still on the pethingy diaphragm leaking.  That bugger is a common problem on this bike.
 Lets get you riding again.  Good luck,

Serowbot... "Look for the floats to be basically parallel with the top of the bowl at full stop."  Sorry but could you elaborate  When I had the carb apart before, they sort of hung there.  Do you mean that the top of the float should be about level with the bottom of the carb, without the bowl?

Blacksmith...  It came stock with a #52.5 pilot jet and I've increased the airflow with the muffler.  I'm not sure if I could go down a jet size.  The pilot screw was 2.5 turns out with the #52.5 jet and stock muffler.

Savage Rob...  Both.  It will start, but I can only keep going by adjusting the pilot screw out.  If I take off on the bike it sputters through acceleration then dies when I decelerate.  The original #52.5 jet was good, except for a little sluggishness at 1/8-1/4 throttle, cruising.  The pilot jet screw was 2.5 turns out.  I thought I could fix both with the increase in jet size.  The plug indicates a rich condition.  Would the jet change be so significant that it would cause this much of a problem?  Could a float issue cause a rich condition?  I also get an odor of gas out of the airbox as well as the vent tubes.  Thanks again for the help.