jetting opinion

[motoman]

All i did was clean the carbs, i didnt change any settings and they were dead on before the bike sat. It revs really good, more like a crotch rocket than my xs750.

Yup, they do that well.....with no load, set correctly or not. Gremlins take care of any setting changes while they're off the scoot...........

[jjz28]

Yeah, i kinda figured, just was hoping they would stay right. I guess I'll find out when i put the airbox on. Man, i hate that box, it is worse than the xs750. I think i am going to order some pods off of georgefix on ebay. He ships so fast. Also, when i was taking the jets out, one of the heads broke off but the other end is still in there. It was the 137.5 ones, I looked at the other jets and it seems the end that matters is the end that is in there so i left it. Also, he put different pipes on it and I didnt see it run after that. Well, when it was tuned perfectly, was a while back so things may have changed since then. I know I'll figure it out with the help of you guys, everyone here is great. Thanks.

[motoman]

Guess you haven't figured out the air box does NOT have to come out to remove carb bank. Remove the PVC hose from upper part of air box and crankcase then remove lower portion of airbox and filter. Loosen the four intake boot clamps then pull air box back off carb intake and lower it and intake boots BELOW carb bank leaving it lay where it is. Remove carb bank and out the left side with it. Doesn't take more than 10 min..........15 tops if your slackin' from start to finish, and that includes removing the seat and tank.

[motoman]

I think i am going to order some pods off of georgefix on ebay. He ships so fast. Also, when i was taking the jets out, one of the heads broke off but the other end is still in there. It was the 137.5 ones, I looked at the other jets and it seems the end that matters is the end that is in there so i left it. Also, he put different pipes on it and I didnt see it run after that. Well, when it was tuned perfectly, was a while back so things may have changed since then. I know I'll figure it out with the help of you guys, everyone here is great. Thanks.

Just askin' for alot of on and off with the carbs if going to pods. If that part of jet is left and not removed, it will NEVER run correctly.....and obviously wasn't prior either. What you think is running good and reality are totally different! Fix the jet issue, don't waste your money on pods(better well spent on correct Genuine Mikuni jets) and use the stock airbox(your carb functions and diaphrams will thank you). Will make life much easier for you and the bike.

[jjz28]

Well my problem wound up being that i didnt have my vacuum advance hooked up. I hooked it up and what a difference, i cannot believe the power these bikes have. Yes, i realized that i could leave the box on because i had to have it on to put the carbs back on. I didnt have the bottom off either. I put the whole airbox in and left the bolts off of it and it slides back about 1" and just slid the carbs in, wasnt bad at all. As for the jet, i will replace it but not yet. It runs great, i couldnt imagine it running better and i was the one that broke the head of the jet off. It is still screwed in the correct depth so i couldnt see how it would matter but i am going to replace it later. If this bike isnt running 100%, i dont want anymore power right now, maybe later but this thing is FAST. When i got the advance on, i barely twisted the throttle on takeoff and the bike tire spun the bike sideways a little bit, of course i had been riding on the driveway so the tire probably had slick dust on it. I love this bike!

[jetmechmarty]

Resynced via the eyeball method. It starts right up and idles fine. I went for a ride and it was running great until it ran out ouf fuel. Fiddled with stuff and it started. I went to reserve and ran out again on the way to the gas station. I was limping home when it occurred to me that I had just replaced the fuel cap seal. I opened the cap and drove it home.

[jetmechmarty]

I still have white plugs

Last month, I ended up installing main jets 120-125-125-120. I mostly did that because that's what I had.

The last weekend I was home, I rode the bike all weekend, loaded and two-up. I did some riding at up to 6000 feet elevation. The jetting is obviously WAY TOO FAT. I can feel it in the seat of the pants. My fuel mileage is down to 30 mpg and less. The spark plugs are still white. The middle ones are white enough to scare me.

So, it's not the jets. When I got home, I checked the intake for leaks. I tried it with WD40 and with propane. I'm not leaking. (rpld butterfly seals)

Currently, I'm jetted too fat on the mains and 42.5 on the primary. I'm going to assume I need to adjust float levels. I'm going to see what the fuel level actually is in the bowls and adjust from there.

I'm working overseas, and I go home in about 10 days or so. I want everything I need waiting for me to get this fixed when I get home. I'm going to take Steve's advice and jet 115 across. Should I obtain some 45 pilots, or leave them alone?

If you're me, and you want all (or most) possiblities covered, what should I have the brown truck bring before I get home? Am I missing anything here? Are the floats my problem? Any suggestions on where to source jets? My local metric dealer isn't very local.

[crazy steve]

Here's a useful link..... http://www.iwt.com.au/mikunicarb.htm

Scroll down, and you'll find a temp/altitude 'correction' chart that may help.

One problem you'll find is with todays' unleaded fuels you won't see the 'color' that's shown in most plug charts, so finding 'white' plugs isn't the clear indication it used to be (that used to mean you were running lean).

Being at the altitude you are, you may not get the fuel economy us 'flatlanders' see. You will be down on power because of that, and you're still trying to move the same weight so mileage may suffer....

[jetmechmarty]

Thanks! I'm keeping that link. I have lost power at WOT, so I jetted too fat. I have the same issue down at 1000 feet. It definately had more guts with 110-120-120-110 jetting, and the fat jets didn't put color on the plugs. I don't know if it makes any difference, but I managed to stay on ethanol free fuel for most of the weekend. Before the rejet, I typically got around 35-37 mpg, unless I got real froggy. I ride more sedately with my Mrs. on the pillion.

With a bright flashlight, the piston tops look black. That offered me a little relief.

I'll be looking for fuel height near the top of the bowl, correct?

[bikerphil]

Marty, why don't you run the jet combo you had before your "garage flooding incident"? It ran OK like that before, no?

[motoman]

Thanks!

I'll be looking for fuel height near the top of the bowl, correct?

Actually 110's across if your runnin' the stock air box and muffs. RUNNING fuel levels are measured down from the carb body casting. That fuel level should be 3mm+-.5mm.

[jetmechmarty]

Actually 110's across if your runnin' the stock air box and muffs.

I have a very stock XS650SK that I've had since new. Somewhere along the timeline, I put fatter jets in it as the factory settings are/were very lean. I would be suspicious of the same in my XS11. The XS650 has been performing well for many years.

Everything seemed OK and I was enjoying my bike. I took several long trips on it. Unknown to me at the time, I had a broken float post, repaired with JB Weld. The repair failed, and my bike caught fire. It could easily have been a total loss. I farmed out the carbs as I had too much going on, then farmed them out to someone else. I eventually got it back running like a "scalded dog". It had never run so well. Since then, I've had other issues, like sticking floats, etc. Right now, the only problem left to solve is the white plugs. It was running great jetted 110-120-120-110, so I should take Phil's advice and put it back. I still need to solve the white plug issue, so I can enjoy the bike and stop worrying about putting a hole in a piston.

[petejw]

hey marty,
as steve said, dont worry to much if the ceramic
on the plugs are white, u want a nice even color on the base
ring on the plug.
id also run 115's mains.
can u take pics of the plugs?

jat is the engine running hotter than usual,
lean float levels will cause the engine to run hotter
more so than lean jetting.

[jetmechmarty]

I can't send pics of my plugs because my bike is garaged in Georgia, and I'm at work in Germany. I'll be here at least to the 15th. Also, my camera is MIA. My wife kindly let me use hers, but see has no cord to plug it in to the computer.

Anyway, it's the electrodes that are white. #3 was very white. The fat main jets didn't fix it, so I'll have to believe it's float level related.

As far as float level goes, I don't understand how this can cause a lean condition. If the jets are passing fuel and I'm running strong, shouldn't that be all that matters? If you tell me the float level is critical, I believe you, but it's something I don't understand.

[petejw]

The float levels are pretty critical they affect
the mixtures from idle to redline, also affects
acceleration as little as .2mm can make a difference.
Definately worth checking out, u should b ablto check
check it with a clear hose so u wont need to pull
the carbs unless there out.