I might be one because I'm finding all sorts of problems that I'm not sure are real problems. I need your help.

Does a black exhaust and exceptionally bad fuel consumption have anything in common? I get about 150 miles out of a tank and I use to get way more when I bought the bike.

I also noticed that the exhaust is becomming very black from all the soot.

Gearing up to second has a slight clink sound and down from third to second has a loud clink sound. The rest of the gears sound like they always did.

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150 miles per tank is a bit on the low side for an essentially unmodified bike and the exhaust shouldn't be overly sooty if it's running the correct A/F ratio.

Just remind us again what mods you've done to intake, exhaust and fuelling...

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I only hacked the snorkel off and I have a single mtc can at the moment. Other than that the bike is stock.



At the moment the fuel display is at the last line and will soon start flashing with the bike at 150, so i probably have another 40 miles to go, so not quite 150 miles per tank. Still less than I should average.



I also noticed that the display jumps between being half full and empty each time I turn the bike off and on again or it will start half full but after a couple minutes of riding it will go down to empty again. I'm never sure what it is.

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As a guide for fuel consumption I've done 500km's on mine before filling it right up & got 22 & a half litres in it, so still had half a litre in it.
Roughly 100k's is 60 miles, so 500k's is around 300 miles. I ran with the F-Trip clocking up to 100k's to achieve those figures. So your consumption is a bit on the low side.
The fuel does swell if you park in the sun too. I've left home in morning in the dark with the F-Trip having just come on,( at around the low 20 degrees ) then leaving the bike till 3 or 4 in the afternoon ( temp's getting up in the high 20's ) finding the fuel level having risen to 2 bars before now.
I have also removed the snorkel, have Akra pipes, & fitted both Kev mod's.
All I could suggest really if you have done any tinkering ( apart from the snorkel ) if you can is to reverse it back fill up with fresh fuel & see what happens then?

With the gear changing, I find with mine now that just pulling in the clutch a small amount ( a quick sort of flick ) & backing off the throttle just a little instead of shutting off back to the throttle stop & letting the revs drop to idle when shifting have smoothed gear changes considerably.

Right, first thing you must learn to accept when owning an XTZ is that the fuel gauge is NOT accurate. Therefore I would strongly suggest (before accusing anything else) you check the actual consumption using the trip meter or odometer. Fill it up to the bottom of the filler neck, do 150 or so miles as you would normally ride, then refill it to the bottom of the neck and calculate the TRUE mpg. Once you have done this we'll be able to get a better idea of what's going on.

Different owners get different mpg with the same set up, so comparing other's fuel tank ranges with yours can be a bit misleading, although 150 is on the low side of the mean within the sample data of 110 owners' fuel economy I've seen. The mean being in the 200-210 range and highest figures tend to be around the 240-250 mark and a few even higher. Have a look at this thread...

http://www.xt660.com/showthread.php?t=18895

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Okay. I'll start with that and see what I get. I generally don't trust the fuel gauge on any bike or car and this only started happening with it jumping like that recently. It use to go from full to empty with no issues. That is why I'm asking because it might not be that my fuel consumption has gone bad, it might just be the gauge or some other electronic part that is acting up.

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