Talk Morgan Forums Morgan Sports Cars Morgan Three Wheeler & Super 3 Catalytic converter removal

Do you need Cats to pass an MOT on a Three Wheeler if it is classed as a motorbike? I've always run my motorbikes without Cats and had no trouble as emissions are not tested.

When the MTW reaches MOT age it could be interesting to see the interpretations of the testers!

Since Euro-5 Regs, yes as far as I am aware. That's why so many bikes were retired from sale a few years ago as they were running carbs which don't like cats particularly. There's a chance that if the M3W is not on the Testers list of vehicles (as indeed my 1999 grey Jap import Subaru wasn't), they just have to do a BET (Basic Emissions Test) which has limits waay higher than for vehicles that are on his list.

I'd keep it on the garage shelf ready for action if I were you!

M3W's fall into Class IV for MoT testing regs here in the UK...this is the same as a family hatchback etc so emissions testing will be indentical.

Take the cats off by all means, but don't bin 'em..!!

More here if wished:

http://www.motester.co.uk/mot-general-information/mot-information-for-motorists/what-is-the-mot

Euro 5 only applies to the manufacturers homologation.

It is not possible to do an emission check on a bike with a legal exhaust as the sniffer probe must go into the exhaust system at least 50cm to eliminate the possibility that the exhaust is diluted by air. The way bike silencers are fitted with baffles the probe will not go in.

The only way to read the mixture is to either take data from the ECU or sample from a lambda probe. Both would require new, expensive, equipment at bike MOT stations. Who pays?

When VOSA consulted informally on this issue in 2008 they concluded that either VOSA would have to take over all bike MOT testing or there would be only about 20 bike MOT stations in the UK. My understanding is they walked away from the issue.

As far as the M3W is concerned no one knows yet what will happen. I suppose it can be MOTd by a car MOT station but they will not be able to check the brakes as no MOT brake tester can do a single rear wheel. Looks like fun!

They test bike emissions here in Italy. My 70's single was tested (no cat) and only just passed.

As far as brake testing is concerned, can't they use a Tapley meter, like they used to use in the old days?

It is still used where a car cannot be tested using the rollers. Any MOT tester worth his salt would jump at the chance of taking a Three Wheeler out for a road test of the brakes!

I'm going to ask my local garage: they have just got MOT capability and went on the VOSA course a couple of months ago. Let me see what they say....

Bike MOT places simply push the bike against the brakes, it seems....

Tapley meter is used to test the brakes of 4 wheel drive vehicles as they cannot be checked on a 2 wheel brake tester.
My last 3 wheeler used to be tested at an MOT station which tested Reliant Robins et al, so we put it on the ramp backwards so the rear wheel sat in the jig.
We managed to test all the brakes on the rollers as they had a flat floor and a 4 post lift and not a pit.
After 3 or 4 years of testing it they got to know me and the car so the testing got less and less and the chatting more and more.
Make friends with your local tester.

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