CBR250R speed cut out

[2isbetterthan4]

hey im new to bikes,got myself a 90' cbr250r. But it wont go over 140km/h. does anyone know how i can change this myself? is it governed by an ecu or on the throttle body? whats the little knob on the left side of the bike engine that leads into the throttle body?
any help is much appreciated
ty
matt

[Two Smoker]

if it is governed it will be to 180kmh, not 140 kmh..... the little knob leading to the carbs is your idle adjustment.... what revs are you pulling and what gear are you in???? are you redlining every gear?

how is the bike running?

[k14]

Hmm, yeah it should easily go up to 140 no sweat. Mine will get up there pretty easily. They are speed limited to 180kph and take ages to get up to there.

There is definately something wrong. Need more info to tell what is the problem though.

[cycosis]

yes,sounds like ya bike has issues,normaly they limit the revs and are restricted to 180 as said in previous

[2isbetterthan4]

it definitly wont go over 180,and it sits at 140 in 5th gear about 12-14 thousand revs if i can remeber correctly(il have to check again). i didnt redline every gear getting to 140,but theres no problems redlining other gears-they go all the way no problems. the bikes running perfect apart from this.
if its not a common prob i guess il have to get it checked out.
thanks anyway
matt

[Mr Skid]

it definitly wont go over 180,and it sits at 140 in 5th gear about 12-14 thousand revs if i can remeber correctly(il have to check again). i didnt redline every gear getting to 140,but theres no problems redlining other gears-they go all the way no problems. the bikes running perfect apart from this.
if its not a common prob i guess il have to get it checked out.
thanks anyway
matt

They only make decent power between 16,000-18,000 rpm, so maybe you've not got enough revs on to get it accelerating past 140km/h Try redlining it in every gear and see how she goes. Otherwise I'm sure there are some friendly wellingtonian KB'ers that be more than happy to thrash the crap out of your bike for you to see if it's working ok :ride:

[Slingshot]

It's possible that the sprockets have been changed to give better acceleration, problem is you lose top speed.


and it sits at 140 in 5th gear about 12-14 thousand revs
You may also like to try changing into 6th gear :msn-wink:

[JohnBoy]

it definitly wont go over 180,and it sits at 140 in 5th gear about 12-14 thousand revs if i can remeber correctly(il have to check again).

a mate of mine once had a A model ZXR250 with the same issue, but his had some sort of bigger bike either ignition CPU or something (not sure) but it told the bike that it was a 400. meaning that it would cut out well before "happy hour".
at a long shot either unplug the speedo or tacho and see what happens...