Dangerously fast powered bikes on PSPs

nachoman
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Re: Dangerously fast powered bikes on PSPs

Postby nachoman » Wed Apr 27, 2016 10:12 pm

A couple of interesting tweets from WA Police Traffic:

https://twitter.com/WAPoliceTraffic/status/725233406989078528
"It may have started out as a bicycle, but put a motor on it and drive without a licence = 28 day seizure"
Image

https://twitter.com/WAPoliceTraffic/status/724904277920092160
"#TEG2 one bike is real and the other is not. Bicycle seized, rider charged with no MDL"
Image

softy
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Re: Dangerously fast powered bikes on PSPs

Postby softy » Wed Apr 27, 2016 10:25 pm

well at least that is sort of a bicycle. Around the roe hwy/tokin hwy PSP there is quite a few motorbikes zipping around the PSPs, generally with pillions too.

hope they catch these as well.

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Re: Dangerously fast powered bikes on PSPs

Postby cj7hawk » Thu Apr 28, 2016 9:56 am

nachoman wrote:A couple of interesting tweets from WA Police Traffic:


Given neither is, on the face of it, illegal in WA, I think the WA Police have some explaining to do. I don't think they have dyno's yet, and so to declare both illegal prior to testing would be a little pre-emptive. Of course, there are practical methods the WA police could use - such as checking the bicycle's speed, but I doubt this has been done either.

I might give them a call and ask what the situation is.

I have seen quite a few petrol-powered bikes on the PSPs to and from Perth, but only some of them were clearly illegal, and I doubt police would have had the capability to make that distinction. I see far more higher-powered electrics on the paths/roads. I even think I have see the chopper style one in the pic. If it is the one I saw, it's speeds appeared to be quite within legal limits.

Regards
David.

Ant_S
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Re: Dangerously fast powered bikes on PSPs

Postby Ant_S » Thu Apr 28, 2016 10:43 am

That Southern Star or whatever it is K-Mart bike with a motor worries me. I would doubt the safety/longevity/reliability of the parts on it doing normal speeds never mind with a motor!
I'm pretty sure I saw it or one the same for sale on Gumtree last week actually.

Agreed on Roe PSP with people on motorbikes/scooters too. I see them fairly often and I only commute 2-3 times a week. Otherwise its really just a couple of electric bikes

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Re: Dangerously fast powered bikes on PSPs

Postby Mububban » Thu Apr 28, 2016 1:44 pm

Ant_S wrote:That Southern Star or whatever it is K-Mart bike with a motor worries me. I would doubt the safety/longevity/reliability of the parts on it doing normal speeds never mind with a motor!


The last one I saw was something like an old Repco, doing 55kph on the road in Midland. Obviously the brakes aren't meant for that sort of speed, but I wonder how the cheap hubs like being forced to do that sort of speed constantly...
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Re: Dangerously fast powered bikes on PSPs

Postby cj7hawk » Thu Apr 28, 2016 2:21 pm

Mububban wrote:
Ant_S wrote:That Southern Star or whatever it is K-Mart bike with a motor worries me. I would doubt the safety/longevity/reliability of the parts on it doing normal speeds never mind with a motor!


The last one I saw was something like an old Repco, doing 55kph on the road in Midland. Obviously the brakes aren't meant for that sort of speed, but I wonder how the cheap hubs like being forced to do that sort of speed constantly...


During testing by the NSW ORS, the top speed of the illegal bicycles was about 33 kph. It's possible someone managed to put an even bigger engine on one though.

The safety of the parts isn't much of an issue. If a bicycle can't do 33 kph, then it's a serious worry with or without a motor.

The brakes are fine - they just won't stop all that quickly at speeds of 55 kph.

It's important to realize that these are still normal bikes, and only have about 5kg of extra mass on the bicycle. In the scheme of things, it doesn't make much difference. The only problem with bearings is when the power assist hides pre-existing issues with bearings such as sand in them, or no lubrication, and even then, it's hardly catastrophic failure. You'll notice if the wheel starts to rub on the side of the bike pretty quickly, but it's not going to fall off.

The issue with illegal bicycles is only that they are illegal. They are not dangerous ( except for how they are ridden ) and the source of the parts doesn't make much difference. People can usually ride faster than most assist setups.

Though I'd still like to see police enforcing the laws more - not because I'm anti-assist - most know I'm pretty pro-assist and pro-petrol as well. It's just that if the police enforced cycling laws more, then there would be a greater acceptance of all kinds of cycling.

Regards
David

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mikedufty
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Re: Dangerously fast powered bikes on PSPs

Postby mikedufty » Thu Apr 28, 2016 5:02 pm

Ant_S wrote:That Southern Star or whatever it is K-Mart bike with a motor worries me.

Looks OK to me, are you not more concerned about the chopper that appears to have no front brake at all?

I saw motocross bikes on the Graham farmer freeway path recently, and a motor scooter and motocross in south perth-como so they are not just out on the Roe Highway.

Hadn't seen much of the fast electric bikes recently until a Stealth-bomber or similar on the freeway path last week.

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Re: Dangerously fast powered bikes on PSPs

Postby RoFlmaTiC » Thu Apr 28, 2016 5:05 pm

Wouldn't the braking issue not be in relation to the additional weight of the bicycle/rider, but the additional mass of the wheel/hub etc? Or is this the same thing? Probably a question for the engineers out there. I'm just trying to imagine using caliper brakes on a car wheel, surely this would require more squeezing force to brake?
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Mediocratus
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Re: Dangerously fast powered bikes on PSPs

Postby Mediocratus » Thu Apr 28, 2016 7:15 pm

cj7hawk wrote: I even think I have see the chopper style one in the pic. If it is the one I saw, it's speeds appeared to be quite within legal limits.

Regards
David.

I think it might have been another one you saw. That one is on a truck marked "Northam tilt tray" and the building in the background is the old Northam Hospital. The photo was taken in Wellington St, Northam outside the courthouse.

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Re: Dangerously fast powered bikes on PSPs

Postby trailgumby » Thu Apr 28, 2016 7:58 pm

cj7hawk wrote:
nachoman wrote:A couple of interesting tweets from WA Police Traffic:


Given neither is, on the face of it, illegal in WA, I think the WA Police have some explaining to do. I don't think they have dyno's yet, and so to declare both illegal prior to testing would be a little pre-emptive. Of course, there are practical methods the WA police could use - such as checking the bicycle's speed, but I doubt this has been done either.

David, that's not how the law works. Under the Acts Interpretation Acts in all states, where the law is framed as a blanket rule with exceptions, it is up to the person relying on the exception to prove they meet the requirements. That's right, the onus of proof is reversed.

The Motor Vehicle Registration Act requires that all powered vehicles be registered, except if it is a bicycle and with an auxiliary powerplant of 200W or less, or in the case of a pedelec 250W (if that legislation has been passed in WA?).

Two points are salient:
1: This means the police don't have to have a dyno. In fact they don't have to prove a thing. The onus is entirely on the rider to prove it us under the 200W limit and that the engine is auxilliary only.
2: Under well established case law, if the power plant is capable of propelling the rider without the rider applying force to the pedals, it is no longer an auxilliary power plant, it is the primary power plant.

Such systems are relatively easily engineered for electric propulsion. I am yet to see any method of ensuring a petrol engine ceases to engage with the drive train when the rider stops pedalling. Immediate fail.

Those riders are looking down the barrel at substantial criminal convictions for riding unlicensed and unregistered.

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Re: Dangerously fast powered bikes on PSPs

Postby cj7hawk » Thu Apr 28, 2016 11:26 pm

trailgumby wrote:Such systems are relatively easily engineered for electric propulsion. I am yet to see any method of ensuring a petrol engine ceases to engage with the drive train when the rider stops pedalling. Immediate fail.


Hi trailgumby,

While I can't say for certain in other states, the original legislation here in WA was in 1991 and was for petrol bicycles. There were no electric bicycles back then, just petrol, and none were engineered to the strict letter of the law, it was just accepted that a typical 50cc engine when fitted with certain gearing wasn't going to go over 200w, or thereabouts. That's pretty much true too, even of today's models, where some are 2hp motors ( 1500W ) but the way they are connected to the bicycle effectively limits them to about 200 to 300W at best.

Then electrics came along, and tried to fit into the petrol regulations, and somewhere, people forgot the original laws were for petrol, not electric. I have formal documents from the department of transport from just a few years back even talking about how great petrol cycles are, how they are completely legal and how pedaling is completely options but "provides range improvements".

The police didn't really care much before these bikes were everywhere, and they get hammered over the useless police response to unlicensed motorcycles all the time, but unlike unlicensed trailbikes, they can easily catch a bicycle. Even a powered one. Not to mention, most powered cycle riders figure they are riding legally, so they usually stop if requested.

And it's still up to the police to prove that a petrol bicycle doesn't comply with the law, or at least, they have to have a reasonable suspicion to act. That is, they need to observe something that suggests the bike isn't compliant. Travelling along at well over 30kph would be one example. Another is if it did a wheelie under it's own power ( very unlikely ). If it had no input covers, well, based on prior examples, they could ask it be dyno'ed. The simple version goes that they must have a reason to believe it doesn't comply. They can also defect notice it and have a few other powers that extend to bicycles as well. Otherwise, they could pull bicycles over for the same reason couldn't they? ( Hidden motors like in the racing world ? )

So, unless it's clearly in breach, and from a photo, there's nothing to suggest it is, then the police are in the wrong here - That's not just my opinion. That was what the department of transport said on the topic as well. As for the police? Well, I've asked them to explain, and we'll see what happens. If I don't get a response, I'll FOI it.

But most likely, I'll get a reasonable response from the police, and then the context will be known. I doubt they'll try to dodge the issue. At least, if they do, I'll escalate. Most likely, I think it will be a case of something tipped the police off that it wasn't legal. But I'll still criticize their approach if that is the case. It's a poor twitter post and only serves to promote hatred and violence towards all cyclists. Gee.... Now cyclists with motors are "Crusty Demons"... Heck, why wait for trains at stops? We could just jump over them according to police...

And that's something that the police do need to respond to IMO.

Regards
David

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Re: Dangerously fast powered bikes on PSPs

Postby cj7hawk » Thu Apr 28, 2016 11:57 pm

trailgumby wrote:Two points are salient:
1: This means the police don't have to have a dyno. In fact they don't have to prove a thing. The onus is entirely on the rider to prove it us under the 200W limit and that the engine is auxilliary only.


Sorry, I should have answered this as well - It doesn't quite mean police don't have to prove anything. It's more a case that the onus is on the owner to ensure compliance - that is, that they have to make sure the output is below 200W. They can't be on a bike that tests at 300W and say "I didn't know" since they have an obligation to ensure that they do not require registration. They also can't claim that they were sold the bike on the condition that it was compliant - the onus is on the individual to ensure compliance themselves. This all came out of the NSW case against a motorized "200w" scooter rider.

However, police still have to prove that a motorcycle isn't a PAPC or Pedelec to prosecute someone.

Regards
David

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Re: Dangerously fast powered bikes on PSPs

Postby 방구 똥 » Fri Apr 29, 2016 12:19 pm

nachoman wrote:A couple of interesting tweets from WA Police Traffic:

https://twitter.com/WAPoliceTraffic/status/725233406989078528
"It may have started out as a bicycle, but put a motor on it and drive without a licence = 28 day seizure"
Image

https://twitter.com/WAPoliceTraffic/status/724904277920092160
"#TEG2 one bike is real and the other is not. Bicycle seized, rider charged with no MDL"
Image


They look like these Z Box which they say is the legal 200W

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Re: Dangerously fast powered bikes on PSPs

Postby Ant_S » Fri Apr 29, 2016 12:52 pm

I suppose my point was more that some of these sorts of bikes are built to a price point, to be cheap in shopping centre sports sections. The demographic for those bikes is people who want a cheap bike to trundle to the shops etc. I would imagine the rims, hubs, brakes, gears, suspension etc just wouldn't be made particularly well as its done cheaply. My g/f bought a couple of k-mart bikes for the kids, they did the job but the brakes were hard to setup & keep aligned, everything rusted very easily, the welds on the rims were very rough, the twist shifters started playing up, there was play in the front suspension arms within a week etc. I'm not overly mechanical but had a go at fixing things but it was a bit of a pain.

~30km/h isn't very fast I understand but day in day out 30-35km/h is a bit of a beating for a bike "designed" for just cruising around pathways etc as a very cheap entry level transport. Throw in someone buzzing around on it, possibly not maintaining it too well and treating it like a scooter. I'm more feeling concern for their safety if something does give out *shrug*

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Re: Dangerously fast powered bikes on PSPs

Postby cj7hawk » Fri Apr 29, 2016 1:04 pm

방구 똥 wrote:They look like these Z Box which they say is the legal 200W


Z Box are, in fact, confirmed legal.

Regards
David

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mikedufty
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Re: Dangerously fast powered bikes on PSPs

Postby mikedufty » Fri Apr 29, 2016 2:09 pm

How are they confirmed legal if they claim 1200w? Genuinely interested as the law/limits seem very vaguely worded.

From the web page -
5. MAX.Power: 1.2kW (AT) 5500rpm

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Re: Dangerously fast powered bikes on PSPs

Postby cj7hawk » Fri Apr 29, 2016 3:12 pm

mikedufty wrote:How are they confirmed legal if they claim 1200w? Genuinely interested as the law/limits seem very vaguely worded.

From the web page -
5. MAX.Power: 1.2kW (AT) 5500rpm


Z Box do sell higher power units, but I wasn't aware of that particular model. However the motors in both those pictures did appear to be their 200W motors, so would comply.

Anyway, I just spoke to Transport Police and they were super helpful. They say there is no change to the rules, and from their perspective, if they see a bike doing 60 down the road, not pedaling, they'll know something is up and take action. If someone's doing about 20-30 on a path, quietly minding their own business, then they probably won't even have a closer look and will assume the bike is legal.

So I don't know what's up with the twitter posts, and neither do they - they did suggest not to worry as they have not been notified of any changes to the PAPC rules, so not to worry about it and apparently they'll look into what was posted on their twitter account and fix it up. They did say there might be some genuine reason behind it ( eg, bikes were over 200W ) but otherwise, petrol PAPCs are still legal on WA roads -

They also confirmed (suggested) that DoT has the say over what is lawful with a bicycle, not WAPOL.

I guess I just wait now and someone will look into what happened with their twitter posts - but after speaking to them, I'm quite confident in riding my PAPC :)

Regards
David.

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Re: Dangerously fast powered bikes on PSPs

Postby wellington_street » Fri Apr 29, 2016 4:42 pm

The person whose bike was seized in Northam had a whinge about it on facebook - he reckons it was only 49cc and reckons he will have it back in no time. Apparently he has quite the history of disqualified driving hence rigging the bike up with a motor for transport as he has no MDL.

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Re: Dangerously fast powered bikes on PSPs

Postby cj7hawk » Fri Apr 29, 2016 6:55 pm

wellington_street wrote:The person whose bike was seized in Northam had a whinge about it on facebook - he reckons it was only 49cc and reckons he will have it back in no time. Apparently he has quite the history of disqualified driving hence rigging the bike up with a motor for transport as he has no MDL.


LoL! Well, that explains why the police stopped him at least. They do have their favorites I guess. Still, they have to follow the law as well.

49cc might save him if they put it on a normal motorcycle dyno, but even that can be argued against in court. All you have to do is cross-graph the dyno output against wind resistance for speed and if the lines cross before 200w, then you could make a real argument that once you factor in wind resistance, it would be below 200W in the real world and that dyno figures are theoretical because they eliminate wind resistance and so the higher speeds are not attainable, hence the remaining graph is invalid.

But if he's just whacked any old kit on his bike, there's a chance he will still get pinged.

All of that though doesn't really explain the police statements, which they will have to explain now a complaint has been made.

I support the police, but because of that, I hold them to a higher standard than I would other people. In this case, whoever made the tweets, no matter how well-meaning, has failed to meet that standard.

Regards
David.

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trailgumby
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Re: Dangerously fast powered bikes on PSPs

Postby trailgumby » Fri Apr 29, 2016 8:19 pm

cj7hawk wrote:
trailgumby wrote:Two points are salient:
1: This means the police don't have to have a dyno. In fact they don't have to prove a thing. The onus is entirely on the rider to prove it us under the 200W limit and that the engine is auxilliary only.


However, police still have to prove that a motorcycle isn't a PAPC or Pedelec to prosecute someone.

Regards
David

Hi David, actually, from a technical legal standpoint no they don't. Recommend you read the judgement in the Queensland appeals court case.

Of course, it is reasonably easy to demonstrate that a bike is a pedelec, and that could be done in court, in which case the prosecution then needs to provide counter-evidence to refute that. For example, they saw the bike being operated under power without being pedalled, such as with dash cam footage.

I expect this is where you are coming from with your comment.

However, the issue is then about evidence, counter evidence and credibility versus technical aspects of the law.

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Re: Dangerously fast powered bikes on PSPs

Postby Thoglette » Fri Apr 29, 2016 8:45 pm

wellington_street wrote:he reckons it was only 49cc

What that has to do with the current 200w/205W laws I don't know

Once upon a time, there was a class of pedal assisted motorbikes known as "mopeds" for which a 50cc limit existed. You still needed a license and the vehicle had to be registered. Maybe one of his "mates" was thinking of that set of rules.

Oh, look, they still exist
DoT wrote:A moped is a motorcycle that;

Is designed to so as not to be capable of a speed exceeding 50 km/h; and
Either-
Has an engine capacity not exceeding 50cc; or
Is not powered by a piston engine.
Whether or not it is also capable of being propelled by pedalling, but does not include a power assisted pedal cycle.
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Re: Dangerously fast powered bikes on PSPs

Postby cj7hawk » Fri Apr 29, 2016 8:58 pm

trailgumby wrote:I expect this is where you are coming from with your comment.
However, the issue is then about evidence, counter evidence and credibility versus technical aspects of the law.


If the accused stood in court and said, "I believe it to be under 200W," then, in the absence of any other proof, that statement becomes the only evidence.

Sure, the policeman could counter with a claim it was not, but then they would have to provide grounds for their belief that it was not, and short of something to back their statement up, I think such a move would be fatally career limiting. Now, if they could say something like "I observed it going down the road at 60 kph without pedaling" then they might have some reason to believe the accused was in error, but that could be explained by any other excuse like "I had just been pedaling" or "I had a very strong tailwind at that moment".

So without a dyno chart, no police officer is going to drag a petrol bicycle rider into court.

Don't forget, that in most states, a solid belief that the bicycle complied is likely to see the accused without a conviction, regardless of the outcome of the case. That is what happened in NSW with the electric motor scooter case.

Besides, WA police aren't stupid. They know how to dyno a bicycle. :) And given enough times they've been accused of botching evidence, I doubt they would ever risk failing to collect the appropriate evidence.

David.

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Re: Dangerously fast powered bikes on PSPs

Postby cj7hawk » Fri Apr 29, 2016 9:00 pm

Thoglette wrote:
wellington_street wrote:he reckons it was only 49cc

What that has to do with the current 200w/205W laws I don't know


A typical 49cc motor will be around 200w on a typical bicycle when geared with typical reduction ratios, with additional power limited by the speed of the motor and wind resistance.

However, in this case, the person saying it might just be confused and genuinely believe that if it's under 49cc there's some obscure law protecting him.

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Re: Dangerously fast powered bikes on PSPs

Postby Thoglette » Sat Apr 30, 2016 11:17 am

cj7hawk wrote:A typical 49cc motor will be around 200w on a typical bicycle when geared with typical reduction ratios, with additional power limited by the speed of the motor and wind resistance.


Power is power. Whether you've set yourself up to access it is pretty irrelevant.

I can't think of a more "typical" 50cc motor than the ubiquitous Honda GHX-50 stationary engine. Which provides 1 to 2 hp across it's entire power band. That's 3 to 6 times 200W

And, without looking closely, the photos above look a lot like the 10hp (7,500w) DeNardis race engines with off road cycle kit. Also 50cc

As noted in the various other threads, one has to try pretty hard to limit a 50cc motor to 1hp. 10cc four stroke at 5000 rpm would be more like it.
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Re: Dangerously fast powered bikes on PSPs

Postby cj7hawk » Sat Apr 30, 2016 1:30 pm

Thoglette wrote:
cj7hawk wrote:A typical 49cc motor will be around 200w on a typical bicycle when geared with typical reduction ratios, with additional power limited by the speed of the motor and wind resistance.


Power is power. Whether you've set yourself up to access it is pretty irrelevant.

I can't think of a more "typical" 50cc motor than the ubiquitous Honda GHX-50 stationary engine. Which provides 1 to 2 hp across it's entire power band. That's 3 to 6 times 200W

And, without looking closely, the photos above look a lot like the 10hp (7,500w) DeNardis race engines with off road cycle kit. Also 50cc

As noted in the various other threads, one has to try pretty hard to limit a 50cc motor to 1hp. 10cc four stroke at 5000 rpm would be more like it.


Hi Thoglette,

Your misunderstanding here is there's no such thing as a 2hp engine, and there's no engine around that can produce 2hp across it's entire band. That's just not possible. The RPM of the engine is the primary contributor to HP. This is key to understanding what I'm saying.

So when they say an engine can produce 2hp, they mean that within it's over-power envelope, it can hit 2hp at 9000 rpm or something like that. This means that it's about 1.5 maximum real HP at that speed. And if that's at 9000 rpm, then at 2000 rpm, it's going to be around 330W output. This is likely reflected in the real engineering data for that engine if you ever look it up.

Now we're down to 330W. Let's assume that we lose about 25% due to poor gearing and reduction and clutch issues. We're down to about 247W now, at the wheel. Let's also factor in that it's a low-quality chinese engine and losses in the dyno at bicycle speeds due to measurement errors, and there's a real chance that a 50cc engine will give a result under 200W.

Really.

Now, if it's geared so that at 2000 rpm it's doing about 25 kph, then in real-world terms, that means that air resistance which increases at the square of velocity will immediately overcome RPM acceleration, which increases at the sum of velocity. Sure, maybe the dyno will show about 700 to 800w, but the argument is that this is in a stationary position, and there's one factor here that hasn't been taken into.

Movement.

Watts, as a unit of movement against force show that you can't measure real-world watts on a stationary dyno, because not all the forces are present.

So, what I said was absolutely correct, and could be verified by any engineer. It's not difficult - it just means that those presenting the argument need to be aware of all the real world factors.

On top of that, DoT, who make the rules, have stated that a reasonable test for a bicycle is that, if it runs in two directions on a straight level path, and the average top speed is calculated, and it's around 25kph ( but not exceeding 30 kph ) then that is a reasonable test for real world conditions... And it's so very easy to do as well.

At this point, it's a bona-fide 200W bike, no matter what the dyno says. Legally so too.

So, as I mentioned, there's a chance the guy will be lucky. But also, as my calculations have shown, it's borderline, so there's also a chance that he will be over. And if the dyno comes over, he will most likely plead guilty anyway, whether he was guilty or not.

For what it's worth, the above test I describe is pretty much how Traffic Police confirmed their view of it yesterday too.

Regards
David

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