running rough

[Gman72]

Hi, tied to start my TRex today after it's been sitting a month or so, light came on as it should when key turned to on position, when i hit the starter, heard a click and nothing, lights went off, turned key off/on.. nothing, no lights etc.
jump started off car, bike idled fine but on opening throttle bike ran rough like it was "breaking down" in the spark and the tacho went up to approx 5000 rpm even though engine barely turning above idle speed. With the jumper leads still connected while running it revved up fine.
Any ideas on what's wrong with it? Battery isn't very old (12 months) and started fine last ride.

[FluroFury]

Gman,try giving the battery terminals a clean and see what happens. Also 12 months IS long enough for a cheap battery to go bad if the bike doesn't get much use and the battery not routinely charged. Fluro

[cal]

Yup sounds like the battery is gone,

[fung]

just to add to the mix
Trx fuel taps have been known to leak down into the cylinder if a bike sits awhile.
Check your oil level.
Smell it too.
If it is fuely, drain the bike, fix the leak and start again.
Cheers
Fung

[Gman72]

Thanks
all for your help and suggestions. looks like i'm off to the battery shop again, hope it is an easy fix like that.