NS125RK- will not rev past 9500rpm ?????

Guest

Ive got a mint Very Happy

20k 1990 NS125RK with a micron exhaust (regulary serviced & run on TTS) but it will not rev past 9500rpm = 85mph, the redline starts at 10500 rpm. Any ideas whats wrong (restricter somewhere like air boxs or carb) should the jets be increased, & what size to or should i change a sproket.
Ive got a spare engine & am thinking of getting a Stan Stephens stage 3 tune, any ideas on top speed & power, ive heard its suposed to be well worth it.

Dylan · Trackday Trickster Joined: 03 Feb 2002 Karma :

Sounds like what happens to me, i was thinking of getting a jolly moto exhasut to help, but if youve got a micron, then maybe its no the exhaust. Ive checked inlet and exhaust and throttle slide, it just sits at 88mph. The standered exhaust is pretty rotten though.
Dylan

Dylan · Trackday Trickster Joined: 03 Feb 2002 Karma :

Sounds like what happens to me, i was thinking of getting a jolly moto exhasut to help, but if youve got a micron, then maybe its no the exhaust. Ive checked inlet and exhaust and throttle slide, it just sits at 88mph. The standered exhaust is pretty rotten though.
Dylan

Stevo · Guest

Hi m8,
I saw a H reg NSR125RK on a dyno on sunday. You are right, as i could see that the power was dropping away around 9.5k, and in fact the dyno operator didnt run it much past 9k. Was quite funny to see the little NSR on the Dynojet rolling road after having watching several Blades,GSXR's R1's and other serious machinery being tested!

G · The Voice of Reason Joined: 02 Feb 2002 Karma :

Is this that it will only not redline in 6th?

On my NS (I assume you do mean NS and that wasn't a typo) I got to about 88 by laying along it with my legs straight out behind the bike, I am about 15st though. I don't think they do much more than that without extra tuning.

Stevo · Guest

stevo · Guest

Thats the one! (wobbly back wheel) so was your GPZ500 a red/white one by any chance? I was interested in seeing it as my m8 has the same bike, and i wondered what it did at the wheel, but i never waited around to see all the bikes done, as even a petrol head like me gets board after the 5th old style GSXR600 in a row has been dynoed. There was some noisy bikes there, and it was interesting to watch. I noticed that you can feel the top end rush of a sports 600 on the dyno, as i never really go that quick on my ZX6R. Did you see the RG500 on sunday, as that sounded really nice makes a change to see a powerful stroker being tested. I think it put out about 85hp but had non std pipes fitted.
What did ya think of the rest of the event? I had a go on a Minimoto, but not the CCM's. Did ya go to Cadwell on the ride out? I didnt bother, cos i was knackered. But i liked the place, and i reckon its definately worth going again next yr.
What about those two dudes on the Fazer600 and the Aprilia RSV! They were nutters. i saw the guy that rode the RSV lying on the floor to take pics whislt his m8 was wheeling his Fazer straight towards him!

G · The Voice of Reason Joined: 02 Feb 2002 Karma :

What was Minimoto like... I've allways wanted to have a go, but never got around to it.

Kickstart · The Oracle Joined: 04 Feb 2002 Karma :

Stevo · Guest

Suppose 47hp aint bad for a GPZ if thats the rear wheel bhp. I wasnt going to get my zx6r on the dyno, (as i have heard that they do about 96bhp std) but id dont really do any harm i suppose, and i noticed that you could get your oil changed by the dyno people if you wanted. Some of those big twins were burping and popping a bit on the overun tho!
Yeah the mini motos were cool, but i wasnt trying to follow that quick dude, as i had seen enough people go over the tyre wall aready, so i stuck to my usual slow wobble.
The RG sounded like an NSR500 when they ran it through the gears, but i was half expecting it to go bang!
I was still a bit worse for wear on sat, so i never bothered with Cadwell, reckon id have dropped by bike before i got out of the carpark! The Guns n roses band was wicked on sat night, despite a load of people coming out of the bar saying it was crap thrash metal as me and my m8 went in.
Yeah i was singing happy birthday too!
The physco on the Fazer should either be doing it for a living, or else he should be in a day care centre! The trouble is that my m8 has a fazer and guess what he wants to learn to do on it?

Kickstart · The Oracle Joined: 04 Feb 2002 Karma :