Problem - NX250 exhaust muffler

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marcus
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Registriert: Di Dez 15, 2015 7:23 pm
Wohnort: FRANCE - near Le Havre

Problem - NX250 exhaust muffler

Beitrag von marcus »

Hi all,
Here is my exhaust muffler from my 250NX from 1990
Bild

The bike can't go over 40 km/h, my sparkplug is black.
If i run the bike with no exhaust pipe, the engine is working perfectly.

When i shake the muffler, i can hear a noise like a piece of metal is moving inside the muffler.
The muffler is from 1990, so i think it is very rusty inside.

I would like to open my muffler for cleaning it, and close it after ( welding a plaque of metal )
Someone did try that already ? any advices ...

Another question, is it possible to buy a new muffler ? in case i can't repare mine
marcus
Beiträge: 42
Registriert: Di Dez 15, 2015 7:23 pm
Wohnort: FRANCE - near Le Havre

Re: Problem - exhaust muffler

Beitrag von marcus »

For one adaptable : MARVING
http://www.marving.com/nx-250/accessori ... o-172.html

I don't know the price.
Is it a good muffler ?
marcus
Beiträge: 42
Registriert: Di Dez 15, 2015 7:23 pm
Wohnort: FRANCE - near Le Havre

Re: Problem - exhaust muffler

Beitrag von marcus »

The original one ( GOSHI 8711 - HM KW3E1 ), is not sold anymore in France :o , the price was: 428 €
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scrambler
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Re: Problem - NX250 exhaust muffler

Beitrag von scrambler »

marcus hat geschrieben: If i run the bike with no exhaust pipe, the engine is working perfectly.

When i shake the muffler, i can hear a noise like a piece of metal is moving inside the muffler.
The muffler is from 1990, so i think it is very rusty inside.
Most original mufflers are rusted through under that stainless steel cover, it may very well be that a large chunk of rust is somehow blocking the outlet (bytheway: is your sparkplug gap not too tight? It should be 0,8mm).
You can try and remove the stainless steel cover. I’ve opened quite a few mufflers and most of them were beyond repair, because the thin remaining steel is impossible to weld.

Bild

There is up to now no really satisfying alternative to the original muffler. The marving is the same muffler as the MSR http://forum.nx250.de/viewtopic.php?f=20&t=376.
If someone desperately needs a muffler I got a few already stripped and aluminized mufflers, e.g. one from a US NX250 (see pic below).
KTN mit TKC.jpg
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marcus
Beiträge: 42
Registriert: Di Dez 15, 2015 7:23 pm
Wohnort: FRANCE - near Le Havre

Re: Problem - exhaust muffler

Beitrag von marcus »

Thanks a lot Michael
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scrambler
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Re: Problem - exhaust muffler

Beitrag von scrambler »

The problem with the original muffler is the stainless steel cover – it literally eats up the normal steel below, that’s why I always remove that cover. The mufflers are then sandblasted and aluminum coated (in my experience the best rust protection ever for mufflers) and then painted with heat resistant paint. You can try it yourself, first you have to grind off the welding points of the stainless steel cover on the backside of the muffler. You have to be extremely careful, the steel is pretty thin (only 0,8mm or so) and mostly even thinner because of the rust.
In this case I was lucky – the muffler is not rusted through (as almost always).
ax1_auspuff_nov2015.jpg
After that grind off the front cap – again, be very careful, because the steel is so thin that it’s very easily punctuated - and it’s pretty difficult to get that welded.
ax1_auspuff_nov2015_2.jpg
But all went well with that speciemen ;) . This is by the way a muffler from a Japanese 29HP AX1. I get them from Japan, because origional mufflers in good condition are impossilbe to get in Europe (and it's the best muffler in terms of performance)
ax1_auspuff_nov2015_3.jpg
If all went well you can send the muffler to Berolina http://www.metallspritztechnik.de/?loc= ... de&lang=en
Sand blasting & coating is about 80€.
After the coating the muffler is snow-white ;-) and can be painted
flammgesptitz.jpg
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marcus
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Registriert: Di Dez 15, 2015 7:23 pm
Wohnort: FRANCE - near Le Havre

Re: Problem - exhaust muffler

Beitrag von marcus »

Thanks again Michael, it is very interesting.
<< If someone desperately needs a muffler I got a few already stripped and aluminized mufflers >>
Yes, I'm interested in buying one of your muflers (stripped and aluminized).
Please, can you PM me, for the price.
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scrambler
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Re: Problem - exhaust muffler

Beitrag von scrambler »

marcus hat geschrieben:Thanks again Michael, it is very interesting.
<< If someone desperately needs a muffler I got a few already stripped and aluminized mufflers >>
Yes, I'm interested in buying one of your muflers (stripped and aluminized).
Please, can you PM me, for the price.
I send an email with pics and price a few hours ago ;)
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marcus
Beiträge: 42
Registriert: Di Dez 15, 2015 7:23 pm
Wohnort: FRANCE - near Le Havre

Re: Problem - exhaust muffler

Beitrag von marcus »

Sorry Michael, but i haven't received your e-mail, i have sent you a PM.
hhgfnx
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Registriert: Di Okt 24, 2023 9:35 pm

Re: Problem - NX250 exhaust muffler

Beitrag von hhgfnx »

I've also been searching for a replacement muffler for my newly purchased NX250.. This topic may end up being pretty useful!

My bike has actually has been imported by someone around 2010 from Germany to Finland where I live - does anybody know if the 1988 model (J model I think) had a catalytic converter in exhaust system? I thought not, but couldn't find exact answer anywhere.
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