MZ/MuZ Riders

what i meant wanted to knw was it possible to remove the cat without cutting the exhaust,ie remove the link pipe and drill chisel it out bit by bit

Ged
I would say not, as it was difficult enough to remove the matrix with the end off! A local stainless fabricator should be able to weld the end cones back on for you at a reasonable price, as welding goes it would not be a very taxing task, (I welded mine back on with my 1970's AC transformer and some 16swg stainless electrodes that have been in the airing cupboard for 20 years) provided that you witness mark the can/cone before removal and do not distort the ends whilst working on the cutting out of the matrix. If you were geographically close by I would do it for you (if I could find my glasses).

cheers for the advice ,i will leave them as they are for the time being ,i may even look into getting some new downpipes made ,in stainless depending on costs

too all
Well lads a positive result on the oxygen (Lambda) sensor. The nice man at NGK and his Japanese colleague pulled out all the stops for us and traced the unit down to the company that supplied them to MZ namely the great Siemens corp. The item is coded thus: (NTK) 0ZA222-RV2 Stock No 0136 priced at £85 + vat. They even contacted my nearest dealer to ensure that it was in stock. I always believed in addressing important questions to the horses mouth and not his ass but this kind of helpful behavior moved even an old cynic like me! The helpful man in question : Mr Ron Merrells, Technical Services Superintendant, NGK Spark Plugs (UK) Ltd, Maylands Avenue, Hemel Hempstead, Hertfordshire HP2 4SD. I have left his phone No/e-mail in my office but will include it in my next posting.

To all
A correction to the id code for the oxygen (lamda) sensor as the one that I posted is not available in the UK (may be in the US) the corrected id is: OZA222-RV1 and the NGK/NTK stock number is 0136. The replacement comes with about 2ft of wires and a connector so I removed the old wire in preparation for the new one (when it arrives) the job took around 1 hour! Usual moronic siting of connectors, buried under hoses etc behind cylinder block involved two people, big screwdriver, long hacksaw blade, and a lot of patience and care as it would be too easy to cut in to water hose. Not helped by tie wraps that are industrial size for holding 16kv cables. All this to remove/re-fit a "consumable" (30,000mile life) item. Just reinforced my lifelong belief that no-one should be let loose with a drawing board until he has spent a lot of time wielding a spanner. It would be very easy to put all useful (and frequently used)connectors on a panel together in an acessible place as I intend to do.

how's the bike doing now you've had the cat out for a while? Running lean or is it ok.

Tom
Machine running ok, a little rich if anything, seems to breathe easier.

boilermaker wrote:Tom
Machine running ok, a little rich if anything, seems to breathe easier.

BM/George would you consider this a worthwhile project or do you think the back pressure surely caused by the cat's is necessary ?? Thanks John

Iceman/John
My main reason for removing the catalysts in my exhaust system was one of safety, a red hot cat box almost touching the bottom of my sump is a stupid idea by any standards and a definate health and safety risk as I do not wish a Hindu funeral! (no disrespect intended). However I also do not think it is a good idea to interrupt the flow of exhaust gasses from a high performance engine as the science of exhaust harmonics relies on controlled constriction/Expansion to make it work at all, (see numerous papers by Ing Walter Kaden) so sticking what constitutes a dam directly across the exhaust path can never be a good idea, only a sop to misguided tree huggers. As to whether it affects the performance, all I can say is that the engine is definately happier, the bike is faster, the fuel consumption is a little higher and I can stop worrying about being burnt to death whilst out enjoying my bike!
George

Hi all...

Good job with removing the cat's, instead of doing all that work can I not just take the bike in to an exhaust service station, cut out the cat sections and replace with same thickness pipes?
I see my 1000S's cats are clogged with black stuff, how the air escape I don't know. Maybe it's time to remove them?

Regards
Werner

qk1
workshop manual link below for download

http://www.sendspace.com/file/6hy4es

QK
I would not recommend taking your bike/exhaust system to any exhaust repair centre for modification because they will not posess the necessary skills or knowledge to do it properly. This is not the exhaust system on your average pickup truck. On top of which the exhaust system is manufactured from Stainless Steel. If you can see black gum deposits in your catalysts then they are not working anyway. I have detailed a simple method of removal elswhere on this thread.

tomtom wrote:qk1
workshop manual link below for download

http://www.sendspace.com/file/6hy4es

Thanks for the link, I've downloaded - stunning stuff.

Regards
Werner

boilermaker wrote:QK
I would not recommend taking your bike/exhaust system to any exhaust repair centre for modification because they will not posess the necessary skills or knowledge to do it properly. This is not the exhaust system on your average pickup truck. On top of which the exhaust system is manufactured from Stainless Steel. If you can see black gum deposits in your catalysts then they are not working anyway. I have detailed a simple method of removal elswhere on this thread.

Thanks
Just for clarity on my side

On your mod the pipes now have a empty widening (cat filter removed) where the cat filters used to be, on my suggestion the pipe will have no widened area as the cat sections will be replaced (pipe and cat filter removed) with the same size pipe (thickness, diameters, material) as the current pipe, is this a bad thing ?

Regards
Werner

Werner
It should not be a problem to replace your "cat boxes" with same size ( AWS 304 Stainless) pipe as I tend to think that the cat chambers were of a larger size than the pipe to reduce the ressistance to flow caused by the matrix. However the practical problem would be one of alignment, you either make a jig, or tack the new pieces in place on the machine and remove to weld. Oh and for gods sake isolate the alternator and the ECU !
George