ZXR 250C power loss

[L.L. Cool M]

Hello, on the lower gears (can't remember which ones, sorry) at about 15,000 RPM the bike has a considerable drop in power. It is really noticeable. Is this some sort of electronic restricter? If so, why doesn't it restrict at this rev range across all the gears? The high gears don't have this problem. The bike should rev happily until the redline at 19,000 RPM surely? Any ideas?

Also, is it easy to remove this restriction if the problem is a limiter of some sort?

[xwhatsit]

I'm sure the ZXR250 crowd can tell you if it's an electronic restriction -- I know some of the high-end litre bikes have such a thing to stop you going arse over tit at the traffic lights, but it seems strange on a 250. Are you sure it's just in the lower gears? Perhaps your carbs are just out of sync, this will result in strange flat spots like you mention.

[N4CR]

hello, on the lower gears (can't remember which ones, sorry) at about 15,000 rpm the bike has a considerable drop in power. it is really noticeable. is this some sort of electronic restricter? if so, why doesn't it restrict at this rev range across all the gears? the high gears don't have this problem. the bike should rev happily until the redline at 19,000 rpm surely? any ideas?

also, is it easy to remove this restriction if the problem is a limiter of some sort?

it shouldn't just be lower gears but yeah anyway what usually causes a 10k problem is the vacuum metering tube from the top of the airbox becoming loose, so check it by pulling tank of and having a peek. it's the thick tube that comes off the top of it and runs through to a metering device of some sort. another rpm cutting device is the speedo metering cable that runs to the ecu, check the plug from speedo>ecu under the front subframe harness part, by the neutral light of the instrument cluster. that will always cut it to 15-16k if unplugged/loose and it sounds liek it's drowning, i think it fuel cuts or runs on 2 cyl, thats wht the speedo cut does anyway at 180k if you plug it in. ****ty fuel can do it and also water in the electronics cuts it at around a similar rpm, it usually dries out after a day or so.