TOP SPEED 50MPH ON NS125R-K??

[puremagic72]

WELL, JUST WENT OUT ON MY NS125R-K AND COULD ONLY GET 50mph OUT OF IT, ALAIN HAS MENTIONED OF UPJETTING, BUT LACK OF EXPERIENCE AND FUNDS AT THE MO, UNABLE TO DO THIS.
Just so dissapointed could only get this out of her, any cheap suggestions, as cant get new jets yet, or will have to play the waiting game???? Think maybe one of the jets are blocked.
Thanks,
Baz.

[Kickstart]

Hi

Stock they should do just over 70 true (and indicate rather more, the speedo was in cloud cuckoo land).

You rejet the carb to compensate for changes to the engine / carb / exhaust / air filter / etc, not to get more performance.

First thing I would do is to check the service items and to do a compression check. My guess would be that either the exhaust is seriously clogged up, or the air filter clogged up or possibly that it has had a light seize in the past (which would result in massively low compression).

It could be the main jet being siezed. If you look at the bottom of the carb you will see a large "bolt" (14mm spanner required). If you take this off you will find the main jet screwed into it (but petrol will pee out if you do this, so turn the petrol off first).

All the best

Keith
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[Hex]

You haven't changed the spark plug recently have you?

Just with the recent cold weather using a colder plug could kill the performance.

Of course the problem is more likely to be along the lines of what Keith said.
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[puremagic72]

yeah changed the spark plug to BR9EIX, but my speedo not working(getting cable today), but my mate rode along side me when i opened her up as much as she could go, and he said it was 48mph!!!
Thanks chaps!!
Baz.

[Robby]

Is it a german import?

I've heard some stories of some german imports being restricted to 50mph.

Don't know if its an electronic or mechanical restriction, or both.

[Hex]

[puremagic72]

no its an italian import, the problem could be down to the piping in between the carb and the engine, its only been taped up, which i have just been told by someone, so there is air escaping and when i open her up theres not enough fuel getting to the engine due to lack of suction.
will post a picture of it soon 2night,
Thanks,
Baz.

[alains]

robby , these restrictions are applied only on the NSR125R in germany due to their ridding licences , anybody from 16 can ride a 80 KM/H since 1992 . these nsr have a black box (added on special electronics) , this is why we in france never buy electronics from them . but about the NS125R (TC01) no restriction worldwide and they should hit 70-75 MPH , so this guy has certainly a prob (piston ,rings , atac valve ?)
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[puremagic72]

well here is the picture of the taped up bit, its between the carb and engine,carb being on the right, should be solid, is this why there is nore top end speed, and when i go up a hill, losing compression, and air leaking. Very poor from the previous owner i think.
Anyone know what this part is called??
Regards,
Baz.

[lilredmachine]

WTF? No wonder it is slow.
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[puremagic72]

forgive me, but wats wtf??
Baz.

[puremagic72]

just realised wat it means, i'm a slow twat!!!!!!!!!!!!

[puremagic72]

do you know wat this part is called??
Baz.

[Aikman666]

Its either because your not getting a steady air flow OR you've blown your rings on it due to running it dry OR its sucked in some nasty air through a hole and it has clogged up the intake/carb needle/completely wrecked your barrell and piston! Only option is really to open it up and have a look.

WHY WOULD YOU RUN IT WITHOUT OIL!? Its there for a reason!
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[puremagic72]

the oil is topped up, i make sure of that.
Baz.

[Robby]

Right. First things first.

Stop riding that bike now. Do not start the engine until that rubber is replaced.

When it is replaced and air tight, see if its working properly. If it isn't I'd be pulling the engine down for a top end rebuild.

That broken rubber is sucking in air, giving you a lean mix. Lean = hot, hot = seized.

Two strokes are temperamental at the best of times. They just don't work if you don't keep on top of the maintenance.

[Hex]

Looks like the jubilie clip round the middle of its slipped and been tightend and as such really messed it up.

I'm not gona bother finding out what plug is in my old one now, you've found the cause of your problems.
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Monkey hanger, Born and bred
My little photo portfolio

[Kickstart]

Hi

Replace it now. Robby is right.

Ask the dealer for a "carb mounting rubber" or an "inlet manifold". I would also buy a new clip for the carb rubber where it holds the carb on (jubilee clip is not likely to fit that well).

All the best

Keith
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