losing power at 80mph

[Grader]

I've owned my AT (97 model 22k) for a couple of weeks and I just did my first stretch of extended motorway running. I noticed that after a couple of miles running at 80mph the engine started to feel like it was running out of power a bit and missing a little like it was running lean. I was still able to maintain the speed but it felt like something was wrong. Afterwards the bike was fine on non motorway roads.

Could this be the dreaded fuel pump. seems strange as it has already been changed a few thousand miles ago by the previous owner, can they fail that quickly? or is the problem something else?

I already have Pierburg pump on order (originally as a spare) so I'll rig it up and try it when it arrives but I was curious to try to investigate the problem as soon as possible.

I like my AT but I'm questioning the reliability record as within 2 weeks of owning it I've had a dodgy starter solenoid and now this problem! I suppose there are always a few teething problems when you buy bikes secondhand from the mechanically inept (the previous owner for example had never checked the oil level )!

Any thoughts or advice appreciated.

Chris.

[Blues N Twos]

Sorry to hear of your troubles mate,

Having just cured my rough running I know how frustrating it can be. If it's running lean you might want to check the airfilter and shine a torch up to where the airbox sits on the carbs. Mine was not seated properly and that was part of the problem on mine.

Let us know how you get on.

Jon

[paultheold]

Give it a full service, change filters, plugs, including petrol filter, check rubber hoses for cracks, clean earth points. balance carbs. Then try the bike out.

[posiwev]

Mine displayed the very same symptoms when I got it.
It turned out the bike had been stood for some time and the fuel had evaporated, like it does leaving a brown residue in the carbs, blocking a few ports and jets here and there, after repeated removal and cleaning it was sorted, apart from I could never get the choke to operate properly, cured this by purchasing a new set of carbs off ebay for 8 quid which didn't even need balancing
Hope the above helps

Andy

[Gardy]

hmmmm... I think I may have the same problem

I picked up mine a about month ago, the bike had been standing still at the dealers for quite some time probably over 8 months

the engine feels fine accelerating through the gears but when you start cruising at about 80 it feels a bit flat and not very smooth.

I tried running on optimax and that made it less noticible

I am going to give it a service and change the spark plugs and hope that sorts it