I'll probably run some tests this weekend and try the 5N. I'm having a problem with stalling/dying when coming to a stop, cold or hot. I think it's the float level again as it was too high and was happening a lot. Lowered it a mm and now it happens less.

Also weird, on my trip I was running at full speed wot in 5th and the bike began to stall. I figured I was running out of gas. I ran it stalling and dying, shaking bike to move gas around, then goes, than repeat again. Made it to a gas station, it was closed. Tried to start the bike and succeeded and it ran well. Next station was .5km away so I filled up but I only got 5.9Lts, bone dry it takes 7.8Lts. Weird. It was behaving exactly as it does when it runs out of fuel. I guess it was some dirt or something in the carb that got shaken out because I had no more problems after that.

 

Well, you'll definitely need your carb running correctly before you make setup changes.. If fuel flow is hampered, any setup will falter. Increasing static pressure with more fuel in the tank which caused the problem to go away, is not a fix to the problem.

 

Well, I've been running it all week with less than a gallon on purpose to see if the issue reappears but so far no more issues. That's why I figured it may be dirt. I ride this thing every day to work and errands so I figure it should have come back if it was another issue.

 

When it comes to 5k elevation.. You are own your own buddy.. 5N will definitely richen up the needle RPM range as well as the transitions on each end of needle RPM..

 

I had been having this issue repeatedly with my bike. Sometimes on the ride out to a trail, it would be like it was out of gas (or the float bowl was emptied). I'd stop for a minute, then it would start up (sometimes with a little choke) and then ride find. Usually, though, it was riding home on the street after riding the trails. I assumed it was as dirty carb, so i'd take it out and clean it. Usually the problem would re-occur, so I'd clean the carb. It hasn't happened in a while now, so I'm not sure what it was. Once it did happen when going WOT about 130KM/H for about 2-3 minutes straight (trying to keep up with my son and his friend riding street bikes), it started to sputter, I backed off the gas and it kept going - it seemed like at steady WOT it couldn't keep the float filled or something.

I never really figured out what the problem was other than the possibility that there was some crap in the carb, although it would happen right after a good carb cleaning. Luckily, it hasn't happened since the summer (wonder if the warmer temps had anything to do with it?)

One question - when it started to stumble, did you go to reserve? I seem to hit reserve somewhere around that same point (about 2L left).

 

rgmr250, that's exactly what happened as you mentioned. It stalled like out of gas, back off, engine catches again, stalls again, repeat. I thought the exact same thing that I was going into reserve but when I checked the petcock was already in reserve. I figured I was out of gas with less kms on the tank and thought I had worse fuel economy that day due to 50 miles of wot on the highway. Of course I realized I did have gas left when she took .5 gallon less than when empty.

You know, now that you mention that it happened to you going back down, I was at a decline in the road when it started, and when it cured itself is when the road started up again. Also if you were going back you probably had less than half a tank, same as me. Fuel petcock is at the back of tank, so maybe there is not enough fuel at the petcock to fill the bowl fast enough when going downhill and with low fuel. Who knows, I hope it doesn't come back jaja.

 

Funny thing is that I haven't had the problem since the summer - I thought the same thing - petcock at the rear of the tank, going down a steep downhill would leave a lower level of fuel at the petcock. Since it hasn't happened since, I chalked it up to dirt in the carb, repeatedly - maybe the sock filter on the petcock was partially off and let some crap in, but since then the tank has become clean? I thought it was odd though that the problem never happened on the trails, where I was going down much, much steeper hills than the street ride home (which is only some very light hills.)

When it would happen to me, generally it would not catch until I stopped the bike (actually it would stop itself, just like it was out of gas). I'd usually tap the carb (thinking the float needle was sticking), then it would usually start back up again, but I'm not sure if it was tapping the carb, or just enough pause/wait for the float to fill back up again. Maybe there was crap in the float needle seat somewhere, although you'd think that would let more gas flow in and overflow the float bowl, rather than starve it.

 

I pulled in the clutch when it would stall to get closer to the gas station since I was sure it was out of gas and would have to push the bike. Then right before it stopped I would pop the clutch and it would start again and I would go WOT to get speed and closer to the gas station but the same would happen again. I caught on that it was able to feed lower amounts of fuel so I popped it into 6th gear and cruised to the gas station. Weird, I hope it was dirt haha. I am actually missing one of the filters in the petcock, the reserve I think, so the dirty gas is definitely possible. Gonna clean it out this weekend.

 

Well, 5N is definitely too rich for 5k feet asl. Lots of sputtering and bogging. I also ran some WOT tests at high rpms. Due to both of those I went back down to 4N and 126 mj.

I also ran off idle and very low rpm tests at various screw turns and found the best setting to be 2 1/4 turns out. wadda do you know, that test for midpoint on the fuel screw was dead on.

These changes together with the correct float height have my bike running the best it has ever ran, smooth engagement and disengagement at any throttle opening, any rpm, any gear. Thanks for sharing your charts and experience Klxster, I couldn't have gotten here without them. Im all set now until I perform the mcm mod.

cheers

 

Fantastic Neonarc, now others @ 5k or so elevation have your setup to go off of.. Mopowah to the masses !! LOL