Highway Code, why the mishmash?

cyclonebri1

sebdangerfield wrote: »

Hopefully I can explain.

Firstly, we need to look at the legal definitions of the vehicles we're talking about as they differ greatly from those used in common language. (all shortened considerably)

Firstly, Motor Car. This is straight forward, 'A mechanically propelled vehicle, not being a motor cycle or an invalid carrage which is constructed itself to carry a load or passengers and cannot exeed 3500kg in weight. Cars come into this catergory, as do taxis, vans less than 3500kg in most cases.

A motor car must have a minimum tread depth of at least 1.6 mm accross the centre of the tyre whether it's a taxi, personal car or whatever.

A motorcyle. A motorcycle is an MPV, not being an invalid carriage and having less than four wheels and the weight of which unladen does not exeed 410 kg. (yes, for those of you not bored yet, this does include some three wheelers and street sweepers because of the open definition).

The minimum tread depth for a motorcycle is 1mm accross the central 3/4 of the width of the tyre and visible tread on the remaining 1/4.

Moped. This is defined as an MPV with fewer than four wheels and (in the post 1977 version) an engine capacity not exeeding 50cc and a top speed not exeeding 29mph.

The minimum tread depth for Mopeds is a visible and clear tread all the way around the tyre.

I know it seems a mess but there's some reasoning to it;

Tread does not give grip, tyre surface area in contact with the road does. Tread simply makes a tyre more efficient at displacing water in wet conditions therefore giving more tyre in contact with the road surface. HGVs only need 1mm of tread because they have more wheels and therfore a much greater surface area in contact with the road therby substancially reducing the chances of aquaplaning. Motorcycles have curved wheel profiles and they have a greater efficiency of displacing water underneath the tyre as a result. Same with mopeds but the limited speed is also a factor.

I noticed in one of the threads above people saying a taxi only needs 1mm. This is not the case if the taxi is a car/hackney carriage. (Local council license requirements may differ but we're talking law). If the taxi was huge and weighed more than 3500kg then other rules would apply.

Well that clears some of it up Seb, but regarding the moped bit why the use of the word "should"? even the way you have written it, ie, with the word "is" makes more sense;)

The taxi bit, well just goes to show when I queried this that not alot of people did know that.

Thankyou

sebdangerfield

SummerRain wrote: »

Even though mopeds are much more powerful these days they are still classed as something inbetween a pushbike and a motorcycle. I think it stems back to the days when mopeds had pedals. I dont think a moped MOT test is as stringent as a motorcycle test either.

They're classed as motor bicycles. But some aren't! It starts to get really confusing!

sebdangerfield

cyclonebri1 wrote: »

Well that clears some of it up Seb, but regarding the moped bit why the use of the word "should"? even the way you have written it, ie, with the word "is" makes more sense;)

The taxi bit, well just goes to show when I queried this that not alot of people did know that.

Thankyou

No probs. I think the wording just comes down to common sense. My understanding, and it's just opinion, is that they use 'should' when there's no law to back it up and they're using a common sense application of the law to real world driving. For example, during my Police Advanced driving courses we had to study roadcraft at great length. This book makes reference to car tyres 'should have 3mm of tread across the tyre. This obviously isn't law but driving at high speed on 1.6mm is a bit daft.

The highway code, when taken as it should be read (i.e a common sense application to using the road) is refreshingly straight forward compared to some stuff out there today. You're just too eagle eyed!!

cyclonebri1

sebdangerfield wrote: »

No probs. I think the wording just comes down to common sense. My understanding, and it's just opinion, is that they use 'should' when there's no law to back it up and they're using a common sense application of the law to real world driving. For example, during my Police Advanced driving courses we had to study roadcraft at great length. This book makes reference to car tyres 'should have 3mm of tread across the tyre. This obviously isn't law but driving at high speed on 1.6mm is a bit daft.

The highway code, when taken as it should be read (i.e a common sense application to using the road) is refreshingly straight forward compared to some stuff out there today. You're just too eagle eyed!!

Having passed my tests for both bikes and cars over 35 years ago and not having read the HC since I thought it was time to. What was basically a pamphet back then is now a 145 page book. Suggest other drivers of my generation do the same. What I have developed into my driving skills, ie, stuff that was not in the HC at that time now is, much more comprehensive, but as they say the "devil is in the detail", just bugs me that words like should are used which have too much lattitude;);)