Nsr 125 Exhaust And Performance Question...

[matt1988]

Its an 02 plate. Deresticted at carb intake.... but im unsure about the exhaust???

Top speed 80mph.. ish
Acceleration... erm i dno, i dont have much to compare it to..

Anyhow... my query is with my exhaust :

Its had some sort of modification fitted to it. My dad and his friend both say that its affecting the performance of the bike due to a loss in back pressure. Here are some pictures to help explain...


I dont understand whats going on inside the exhaust (second picture)....
Is it deresticted already?

My dad is thinking of manufacturing a plate to weld on the end of the exhaust with a smaller outlet to increase pressure... is this a reasonable idea??

I'm strugglin to find a second hand exhaust at a breakers yard and such.... if some one knows of one i'd be real chuffed if ya could let me know!!!

Cheers anyhow

Matt

[ms51ves3]

Usually there is a little washer in the exhaust where it meets the manifold. It is welded in, you drill the welds out and pull the washer out of the exhaust, then it is fully de-restricted.
Your exhaust looks strange though, the exit (black bit) looks too long.

https://www.bikez.com/pictures/honda/1997/1147_0_1_2_nsr%20125_Image%20credits%20-%20JoTT.jpg

[Jamie S]

Have a read here.
https://nsr125.com/derestrict.htm

[alains]

look your serial number between the yokes , it begins by ZDCJC22 then you have a letter . if it's a B or E your bike is electronicaly restricted , otherwise even with your restricted exhaust you should reach 90 MPH
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the worst day fishing is better than the best day working

[moonym20]

wow i aint ever seen an NSR with an anti aircraft gun welded to the end of the pipe!

from the pictures it seems to be cosmetic, you need to take the exhaust off and look for the restrictor fitted to the inlet of the exhaust, you can't miss it if its there mate

hope it helps
____________________
A scientist crossed a skunk with an owl. He's got a bird that smells but doesn't give a hoot

[ncrn]

I'd try get that weird black bit off the end I'm not sure what thats helping.. not sure if it'd be limiting but I wouldn't imagine it is good for the limited flow.

Check the serial number like alains suggested. Otherwise you are going to have to take your exhaust off so you can have a look at the end that connects to the engine, theres some pics of it on nsr125.com when its restricted.

Edit: Actually looking at your exhaust it seems to have been cut off, the end should look like this;

https://i55.photobucket.com/albums/g123/ncrn/nsrexhaust.jpg?t=1197887250

But yours appears to have been cut so it can sit in the weird scud launcher at the end.
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Past: 55 Sym Jet, 91 ZZR250, 03 NSR125R. Present: 97 ER-5.
https://www.nsr125.co.uk - NSR Owners forum.

[matt1988]

Yer ive been on www.nsr125.com/de-restrict about a million times.... but thanks for the tip anyway...

...And my serial number is ZDCJC22C..... a UK number.... so there should be no electronic restrictions.

I think the crazy thing on the end of the exhaust has been added to make it sound a bit better, which it does... it does grumble abit more at low revs. But i'm interested in the perfromance and not so much the sound of it!!!

Look at the second attachment in my first post.... just click download

....Or look at this pic?

But yer it does 80mph tops, that was to the limit. Its had the intake restrictor taken out of the carb.... i don't think the airbox has been modified like on alains guide.... im sure this alone wont add the 10mph that alain says it is lacking will it?

Any ideas??

[alains]

the can has very little influence on the performances , i think you need to upjet your carb as 138 (main) , 42 (slow) , 65 (power) and set needle at 2nd notch from top
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the worst day fishing is better than the best day working

[ncrn]

Your exhaust looks erm messed up if I'm honest. I'd be inclined to get an exhaust that hasn't been messed about with, as 2 stroke exhausts are expertly shaped to give it the best power, and when tampered with you can get some pretty funky results such as very low power being developed.
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Past: 55 Sym Jet, 91 ZZR250, 03 NSR125R. Present: 97 ER-5.
https://www.nsr125.co.uk - NSR Owners forum.

[Pajo?.NSR]

Hello,
When the my NSR has mark ZDCJC22B... so isn't restriction in exhaust? NSR had CDI639, TV- 124, trisky 132, 55, 38, needle be on second slot from bottom and chain gear 15:35... Now am bought CDI open , TV- 78, trisky 135, 55, 40, needle them to a middle slot and chain 14:38 , I don't know if cut exhaust?! Thanks for answered

[Noxious89123]

[salty21]

his jetting is a mile off for a start and with that gearing hes good for 130mph+ lol
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04 NSR 125(sold) ---- 03 CBR 600rr(sold) ----90 pan euro ST1100 '' ----02 CG 125
94 CB400 Super Four ---- 2000 VTR SP1 (sold) ---- 08 ninja p8f(sold, meh) ----05 CBR600rr

[TUG]

What the hell is that exhaust? Thats worse than the one that came with my FZR , it was off a 250 or something. If your after that bike burn that exhaust!
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Haz ER-5, innit!

[Pajo?.NSR]

My english is very feint. I'm sorry to all. According it him (alains), when is ZDCJC22B so is electronicaly restricted. I don't know if is restricted exhaust?!

[alains]

of course exhaust is restricted but different way of english bikes and far more difficult to de-restrict . the best way is to buy a race pipe
____________________
the worst day fishing is better than the best day working

[Pajo?.NSR]

I haven`t money for racing exhaust Can you help me de-restricted exhaust? Restricted exhaust is very bad or no ?

[alains]

if you read french , have a look here https://ovmaxx.free.fr/index.php3?rep_rubrique=nsr125&page_centre=debridage
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the worst day fishing is better than the best day working

[Pajo?.NSR]

de-restricted exhaust is very difficult... I`m angry! I must cut the exhaust on two places! Where I buy any cheap exhaust?

[alains]

no second hand on ebay actually , the minimum price for a new one is 236 euros without shipping
https://www.fischerkfz.com/hauptnavi/125er.php#Tyga
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the worst day fishing is better than the best day working

[Phil_P]

[alains]