Hi all im a new member and fancy a nsr250 ive seen a minter looks almost new mc21 7000km but are a bit worried about it been restricted ive been told its a wire splice and a few holes drilled in airbox is this the case? i was going to get 350lc but like the look of the nsr,are the performance similer or better on the nsr has anyone got any info on best model to go for what to look out for any advice would be fantaastic thanks

General consensus is that the MC21 offers the best compromise between ease of restiction and most modern design. The MC18 is fast straight out of the box, though an older design. The MC28 is the newest design with it's (gimmicky) smart card ignition and single sided swing arm, but a lot harder / more expensive to de-restrict.
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MC21SP Plaything
BMW F800GS Bumblebee
Triumph 9551 Daytona Big boys toy
FJ1100 Sporting relic
GTS1000 oddball

As someone who has had both, and a lover of all things LC i would say go for the MC21. Just as quick in standard form, and way quicker if derestricted.

Brakes and handling an LC rider can only dream of.

The only down side to the NSR is getting hold of some of the parts.

Hi and thanks for getting back to me. Do you know if it's true about the wire splice and holes drilled in air box to de-restriced the bike?
Also is there anything i should lookout for when buying one?
the one iv'e seen is an import which told they all are has only done 3313 miles is 1990 model and wants £3150 with 12month tax and test,i know it's hard to say without seeing it but does that sound a good price the bike is as new condition. iv'e had A LOT of bike in my time but never an nsr
any advice/help would be good thanks

parts for MC21 are largely available.

parts for MC18 are harder to come by. cranks for 1988 version are no longer available. cranks for 1989 version can use a modified MC21.

pistons and barrels are available for both.

don't let a wire splice or holes drilled in air box scare you. government regulations only allowed 45 HP for this "beginner" bike. HP was reduced via ignition timing to comply. Almost all of these bikes had this restriction removed to gain extra HP via a simple wiring splice.

additional air flow also gains some HP. tried and true, four 1" holes do the trick.

you can learn all the details about both right here. learn to use the search feature.
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MC21R9N track
MC18R2J track
CBR954
CR250

If it is truly immaculate and that is genuine milage, rip his hand off!
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MC21SP Plaything
BMW F800GS Bumblebee
Triumph 9551 Daytona Big boys toy
FJ1100 Sporting relic
GTS1000 oddball

i think you have all made my mind up for me, just a few more questions if thats ok, how reliable is the mc21? im only going to use it for quick squirts out on a sunny sunday so how oftern should the rings be replaced?
iv'e used to search section to try find pictures of exactly what/how to do the de-restrict wire splice but although id like to think im good with bikes i am rubbish with computars and can't find any,when i get it i will post some pictures and see what you all think
thanks for all your advice

If you leave it restricted it'll be good for 20,000 miles - provided you run it on high quality oil, don't leave it standing for months with fuel in the carbs or thrash it from cold.

If you de-restrict it it'll be good for 10,000 I suspect - has anyone done that many between rebuilds? I usually sieze mine before things wear out...
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MC21SP Plaything
BMW F800GS Bumblebee
Triumph 9551 Daytona Big boys toy
FJ1100 Sporting relic
GTS1000 oddball

I wouldnt have thought derestricting it had that much effect on maintenance intervals unless you were caning it flat out all the time, ie, you could still be riding it as if it was restricted, and certainly if you were only riding it on the road the difference would be negligible, as long as you use a decent oil and maintain it properly
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Proud Father of , 05 ktm 400exc supermoto 2018 honda crf rx supermoto

Agreed, but when you have 60hp available and it pulls into the red you kinda can't help yourself...
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MC21SP Plaything
BMW F800GS Bumblebee
Triumph 9551 Daytona Big boys toy
FJ1100 Sporting relic
GTS1000 oddball