LC8 probem
 

Hi guys..
Does anybody in high altitude 4000-5000 mt. (Tibet) had this kind of problem:
motorbike runs well then it cold, but as soon as it reach normal working temperature range, it had a choke and lose a power. Also it gives a lambda probe error from time to time. Does it a atitude problem or a Chinese fuel problem? We got this problem on a 3 LC8 bikes.
P.S. The fuel pumps are ok.

It really sounds like the same symptoms as the lc8 / 950 carb version had which was down to carb icing - it was a real persistant problem in cold weather - does it go away after stopping for a few minutes then start happening again after a few kms ? if its intermitent its unlikely to be the fuel - however I am not sure if injector bikes can or do get icing. But its seems possible to me with the height your travelling at. Maybe try an anti icing additive to the fuel before stripping anything else down. Good Luck Jake

Also The chinese fuel probably does not help is there a plug on the 990 like on the 950 which you de activate - for poor fuel running, this may also help.
Also maybe a drop in air pressure may cause symptom if the engine requires more air fuel than it can draw simply because there is a lowering of average air pressure and less density then the engine can not work as it would at lower areas - I would not have thought 4 /5000 meters would be outside the bikes operating capability but maybe it is try dropping an e-mail to ktm they might help as they will know what relevant flow rate is required to keep the engine running properly.
once again good luck.