hi im new hear im gordon i have a 1999 buell x1 lightning its runing real bad, runs ok for about 12 miles then it starts to miss and backfire and no power, cleend all the wiring concessions, new plugs, new cdi unit,some days its ok then it just get real bad
can some one give me som help thanks

Has it got any fault codes stored?

I'm gonna go out on a limb and say it's something to do with the temperature sensor in the rear cylinder... assuming that it has one fitted. Do you know if that upgrade was done, Gordon?

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Good in straight lines
2001 X1 "The Tart's Handbag"
2001 FZS1000 "The Fridge"

As a left field suggestion: fuel tank breather?

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Be seeing you

I

yes i thought that so took cap off while i was riding thanks

hi no i dont know if the upgrade was done thears no engine managment light on when it playing up and some times it will stop and run ok for a bit thanks

Temp sensor problems don't always flag up a fault code..............think all X1's had them fitted as standard but does make them run like shit when playing up.

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2001 X1 2009 1125CR 2006 Uly X3 2010 Uly a fully Maz'd S1 and a 1991 RS1200 Westwind.

If the engine runs well when cold and starts coughing when warming up I also would suspect a faulty engine temp sensor. I also heard about an X1 with similar habit, caused by a faulty fuel pump, but in that case it didn't even run longer than 2 minutes, Also check intake air temp sensor if you are using a third party air filter, because it seems that some of them make hot air from the engine run along the air temp sensor, which then leads to a very lean mixture.

If you stop the engine when hot and coughing and you start again, will it run well then about the first half minute or so?

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"It is often said that before you die your life passes before your eyes. It is in fact true. It's called living."
Terry Pratchett

Nope, they were an upgrade to the '99s, IIRC. Mine was fitted when I got a leaky rear rocker (I think) gasket, essentially fixing my leak FOC.

It's a while ago but I think that the upgrades meant you have a wire poking out from the hole in the middle of the top of the rear rocker cover. Not sure what could be done to check the diagnosis or fix it, if it is the rear temp sensor.

Where's Maz anyway, letting me loose in the tech forum like this!

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Good in straight lines
2001 X1 "The Tart's Handbag"
2001 FZS1000 "The Fridge"

ALL X1's have a temp sensor......tis one of the main inputs for the EFI.
99 models had them next to the rear spark plug but a 'mod' saw them moved into the centre of the rear head, which is where they're located on all subsequent models.

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Mithered ta death.
92 MB
96 S2T
98 S1W
00 M2
01 X1
03 P3
10 CR

Ah... so mine did need an upgrade but, as Kev said, they all had them stock. Thanks.

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Good in straight lines
2001 X1 "The Tart's Handbag"
2001 FZS1000 "The Fridge"