I took my 1990 NC30 for it's MOT today and failed due to the following:-

001 Centre lower Exhaust is leaking and excessively noisey.
002 Centre lower Exhaust excessively deteriorated.
003 Centre lower (clamp missing) Exhaust has part of the system missing.

From what I've described which parts does it sound like I'll need to source in order to get it through the re-test? I've got the parts list for Rick Oliver and the website for David Silver Spares (which I've just purchased a number of service items) but I really am a novice so I'm not sure what will need to be sourced to complete the job.

I've a biker friend with a good history of home servicing and working knowledge of Motorbikes who is helping me along with the service in the next few days, so Ideally if the exhaust job is relatively straight forward we can complete the work ourselves. Thought I'd ask on here first for some model specific advice...

Ahh.. You have got the famous rotten collars. The only part of the system that is made from mild steel.

You can get collars welded on for not a lot. That is your fix. No amount of bodging will see that sorted properly.

An ideal time to get a nice Japanese half system....

That was fast!

It's gonna be a weld job then as I don't have a lot of disposable cash at the moment. Is this what is causing the "excessive noise"?

Regarding the missing centre lower clamp, is there an exhaust diagram knocking about so I can try and work out what it is? I noticed a lot of the clamps and gaskets can be sourced quite readily from the companies mentioned on here.

http://www.hondaoriginalparts.com/honda ... od_01=5713

Just found this via Google, might come in handy for others looking parts diagrams.

Look on the 400greybike.com home page - there is a doc library. The twon front pipes are clamped into the rear section. The outers of the rear section are mild steel and rot. Often from underneath the clamps.


The welding is no worries if you have someone local..though getting the pipes off can be a ballache the first time (especially if they have not come off in the last few years!)

As Mark has said, basically either get friendly with a local welder, or find some money from somewhere and get yourself onto www.jap4performance.co.uk and buy a new system. Either way it's going to be a battle to get your original system free from the bike. I suggest time, penetrating oil, and patience. And a Haynes manual!

[quote="Mr Nice"]
001 Centre lower Exhaust is leaking and excessively noisey.
002 Centre lower Exhaust excessively deteriorated.
003 Centre lower (clamp missing) Exhaust has part of the system missing.
quote]

Centre = Middle
Lower = Bottom.

Find the lowest point of the exhaust thats roughly in the middle and you'll find the problem.

The various parts of the system, front and back all join together here.

Clamp missing is self explanatory.

As been said, these are made of ordinary steel so looks like they have rusted away.

Excessive noise will be the hole where the clamp and what not have rusted away.

They need to be cut off and new parts welded on or the system replaced