Ah, yeah, my bad. I'm currently living in Findlay, Ohio. Just south of Toledo.

Crashmk1 wrote on 06/22/18 at 07:55:41:


Most likely blueing or bronzing of the header pipe is because of being too lean. The additional fuel, as contradictory as is may seem, helps for a cooler combustion. So, being lean from the factory means a hotter combustion hence the blueing or scorching of the header. More fuel (which the EPA tries to restrict by plugging the air/mix screw and making the carb lean from the factory) means cooler combustion and less chance of blueing. What we/you don't know as you stated, is how long it has been like this and did or did/not the previous owner make any carb adjustments or change jets.  The only way to know is getting in the carb, looking at the jet sizes and needle setting, and then go from there.  Heck, you may find that it just needs a good carb cleaning and that alone may provide some resolve.  It could be simply a sticky slide.  But if the carb is all stock you will likely reap some rewards by doing the needle spacer (white spacer) mod which richens up the throttle area where you are getting the bogging.  

HOWEVER, you could find that the previous owner raised the needle too much or put in an oversized jet causing an overly rich mixture.  One give-away of an overly rich mixture is (at regular running temperature) is if you are getting any sootiness out of the muffler when you get into the throttle. You can also look back at the rear brake lever area behind the muffler and see if there is excessive soot back there. If not, you're probably just dealing with the classic factory lean issue.

Yeah, most likely a lean issue them.

Well, you can try to do the air/mix screw adjustment on the right side of the carb with it on the bike but that probably isn't going to do you any good because the air/mix screw only impacts the mixture at idle.  Once you get into the throttle about 1/8 turn or more you're operating in the area that the needle controls, and that seems to be where your issue is.

If you don't want to risk it, maybe try running some sea foam through the next tank of gas. Also, as silly as it sounds, make sure you have good fresh fuel.  If the previous owner let it sit and you are still running on his tank of gas, the ethanol in today's gas goes stale and you will get poor running of it's been sitting in the tank for several months.

At the end of it all, you really need to get into the carb at some point and know for certain what you have going on in there.  Truthfully, once you do it the first time and get the fear out of the way, you can drop, clean, and replace a carb in an hour or less.  The only thing in there to be careful with is the 'rubber' diaphragm. As long as you don't tear it (it is quite durable) then the rest is just cast metal and brass jets aside from the plastic float.  I never did it before I got my S40, and now I can do it blindfolded if I had to, thanks to the folks here  

Nice bike. Identical to mine. Looks well taken care of. Stale gas can cause it to run not so perfect, but if they never got in the carb then it just needs the needle spacer mod.  That bike is way too nice and clean to not be able to be fine tuned very easily.

Can you tell if they removed the brass plug covering the air mix screw on the right side of the carb. If no, likely they were never in the carb as that’s usually the first thing that is done. If you aren’t sure, see tech section images, or take a closeup pic of the right side of the carb and post here.  

Just noticing from the picture this bike has a Dyna muffler on it. This is a common mod on this site. Having the Dyna on there leads me to think the previous owner probably messed with the carb or did the white spacer mod. I, like others have stated, think checking the carb is in order. Basically to verify the jet sizes. You will also need to change these once you get to Florida because the elevation will affect your jet size and air/mix. See Lancers thread in the Market Place for jet kits.

One question I have is, do you know if the petcock is stock? Mine, a 2005 had similar bog issues and would cut out at low speeds because of the failed gasket in the petcock. One other simple thing is idle RPMs, the PO of my bike had the idle screw turned too low which also contributed to the cut outs. Though at speed this shouldn’t be a problem for you. I only mention it because it will affect tuning the air mix screw and proper jetting.

Definitely try to fix this yourself. You’ll have a better understanding of the bike and will be able to fix and diagnose issues if she ever leaves you stranded on the side of the road.

Hard to say what to do regarding jetting until you know what's in there. If you are lean at 800', you will be even leaner at 100'. Lower elevation equals denser air which equals more parts air per volume. So, there is even more air at 100' mixing with your same fuel volume.

Until you know what's going on in that carb, everything is just an educated guess.  This whole thing could not even be jet related if you found out that you have bad gas, a sticky petcock diaphragm, sticking carb slide, etc. First order of business should the easiest, fresh gas. Then try to run on prime to see if it is a sticky petcock.  If prime makes it better, it is a petcock or a leak in the petcock vacuum line.  After that, you just gotta get in the carb.

Cool, then it needs the needle raised first, test that, then consider jets. For reference, I am at ~600ft and have rejetted to 152 and 52.5 with the needle raised a couple of washers worth, and I’m running very smooth. Every bike can have its own minute quirks, but I bet if you were close to these settings in FL you will get the bik esmoothed out. Too bad you can’t stop by...