Project Q bike

[flecc]

All road users have equal rights to use the road. My advice on roundabouts, and indeed everywhere on the road, is to have confidence and take command of the situation. On a bike that often means taking the centre line of where a car would be, controlling the traffic behind in exactly the same way a car does, accompanying that where advisable with bold, clear hand signals.

Most drivers appreciate that sort of riding since it leaves them in no doubt of the cyclist's intentions, but those who don't can be dealt with appropriately.
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[electric.mike]

flecc

Most drivers appreciate that sort of riding since it leaves them in no doubt of the cyclist's intentions, but those who don't can be dealt with appropriately

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as a cyclist i agree and as a motorist i agree, and lets face it if your arm is out for a right turn and a motorist cuts you up your half way to expressing your opinion.

FatMog if the road is too dangerous use the path, the last directive i can find from government to police forces was to ignore cyclists on paths if they posed no danger to pedestrians and it was obviously a safer situation for the cyclist.

be bold but not stupid, leave other motorists in no doubt what you intend to do.

mike

 

[FatMog]

Thanks for the advice, guys... I'm reasonably confident now with the more minor r'bouts, and definitely follow the advice of my long-ago driving instructor which was ' whatever you're going to do, signal, do it and don't dither!'.

But - MUST invest in a mirror, especially after everyone's recent discussions in this or another thread, can't remember which.

When I ride horsy on the road, I get to carry a big stick. This is ostensibly for encouraging my equine friend to speed up the amble slightly, but is really for beating off foes of the canine or auto variety. Any passing car which has threatened to to take the hind legs out from under us gets a whack on the roof, which alarms pony not at all but scares the willies out of the driver.

 

[flecc]

But - MUST invest in a mirror, especially after everyone's recent discussions in this or another thread, can't remember which.

Yes, that really is a must for safe riding. I won't ride without one now, the difference they make is so great. Apart from other considerations, I don't think it's fair to other road users that the slowest and most overtaken vehicles, bikes, don't have mirrors for making allowances for others, like the driver who is already committed to an overtake.
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[Mike Robinson]

cycling on the pavement?

FatMog if the road is too dangerous use the path, the last directive i can find from government to police forces was to ignore cyclists on paths if they posed no danger to pedestrians and it was obviously a safer situation for the cyclist.

I went to the local police/neighbourhood meeting with a view to finding out what was on the agenda in my area. Imagine my surprise to find out that their main targets at that point were cyclists on the pavement - I went along as an upstanding citizen and find both myself and my young son are on their most wanted list. I guess that the local burglars, muggers, rapists, murderers and hit and run drivers (I live in Streatham so I could go on) could at least relax for a while.

The 30mph road outside my house is a lovely road boardering a park but drivers would often reach 80mph down here. We complained but nothing happened until a motorcyclist was killed outside my front door and now we have speed bumps. This has slowed down some but others, no doubt with company vans and 4*4's, haven't slowed down. I have no intention of bicycling down this road. I did of course express my opinion regards careful cycling on the pavement and no doubt my photo is on all their notice boards by now.

I'm (just) old enough to remember when the police were there to keep society safe from criminals but now feel they simply want to criminalise the lot of us. If I do get stopped then I'd hope for an intelligent copper but I suspect with quota's for arrests etc I suspect I'd still just get charged.

Mike

 

[flecc]

I'm (just) old enough to remember when the police were there to keep society safe from criminals but now feel they simply want to criminalise the lot of us. If I do get stopped then I'd hope for an intelligent copper but I suspect with quota's for arrests etc I suspect I'd still just get charged.

Mike

I think the problem we have in London now Mike, is the expansion of the Met from 24,000 to about 33,000, plus thousands of PCSOs and other types pseudo police officers. They have to show some evidence of effectiveness, and given those numbers, they are running out of traditional targets, leaving us in the firing line.
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[electric.mike]

Mike Robinson

i cant find the original web posting but if you read down this page you will find what i have printed of for info

mike

 

[Mike Robinson]

An interesting article but knowing the law doesn't mean I agree with it - I suppose I have the choice of exposing my son (and myself) to fast moving traffic, paying the fine, not paying the fine and explaining why (do they do breakfasts still in jail?) or smacking the officer concerned and hoping they'll move on to even easier prey ... perhaps old ladies loitering at the side of the road while waiting to cross.

I was told the law was introduced to combat hoody wearing youths from pinching handbags while riding down the pavement but then your article mentioned that the law couldn't apply to anyone under 16!

The effect is simply another law that will at best make the common man feel that the police are brainless fools and at worst label him a criminal.

I looked up arrest targets and found this being discussed this year ...

The Police Federation annual conference in Blackpool will debate whether judging officers purely on how many arrests, cautions or on-the-spot fines they can deliver is making a mockery of the criminal justice system.

I suspect they are too late.

Mike

 

[Ian]

According to the article the law was introduced in 1835, long before hooded youngsters had bikes fast enough to snatch handbags, the relatively new part is the fixed penalty notice which is arguably better than a court summons and the possibility of a £500 fine plus a criminal record.
I think the following quote from the article sums up the spirit of the law.

I should stress that the issue is about inconsiderate cycling on the pavements. The new provisions are not aimed at responsible cyclists who sometimes feel obliged to use the pavement out of fear of the traffic, and who show consideration to other road users when doing so. Chief officers recognise that the fixed penalty needs to be used with a considerable degree of discretion and it cannot be issued to anyone under the age of 16. (Letter to Mr H. Peel from John Crozier of The Home Office, reference T5080/4, 23 February 2004)

So remember "rules are for the obedience of fools and guidance of wise men" and just carry on as before, but stay away from CPO's, hobby bobbies, anti cycling enforcement officers, gestapo or anyone else in a uniform you don't recognize.

 

[FatMog]

Hooray!

But - MUST invest in a mirror, especially after everyone's recent discussions in this or another thread, can't remember which.

I've just completed my first flecc-inspired mod. OK, it was just fitting a mirror but what a difference - at last I know what's going on! Why on earth aren't they fitted as standard to road-going bikes??

 

[flecc]

Well done FatMog, you are hundreds of time safer now. When I first added a mirror to a bike, it was a revelation, and there's no way I'll ride without one now.

I've made myself unpopular in cycling circles by saying they should be fitted on all bikes by law, but I'm unrepentant and still maintain the same. They're far more important than a bell.
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[JohnInStockie]

Ezee Quando vs Wisper Works 805fe for Q bike

I was just looking at the specs for these 2 bikes and wondered what people think. It seems to me that the 805fe is surprisingly a lot lighter than the Quando (which is almost as heavy as my Twist)

 

[coops]

Q bike implications for universal hub-motor bike design?

It seems we're thinking on similar lines John (though you may not see it at first...!)

Bike weight is a factor on hilly routes, or for stop-starts in built-up areas, though rider weight is a much larger factor as has been said before. Motor peak power output is another, and will always be necessary for good acceleration or climbing. I've been musing on another aspect though:

The Q bike has given me much food for thought at times recently: having taken in the very good efficiency gains achieved in large part by rider gearing allowing pedalling and the significantly lower rolling resistance of the m+ tyres, in addition to the inherent advantage of smaller & lighter wheelsize for lower energy (& hence more efficient) acceleration, I am still pondering one thing though: whether or not the motor gearing and wheel size of the Q gives an added advantage with implications for design of "universal" hub motor ebikes (for anyone who wants to try to put one together ):

In varied terrain, is there an implicit efficiency gain from a 20" wheel (e.g. the Q) vs 26" wheel (e.g. the Sprint; Wisper Works 905e) when each has a motor "normally geared" for such (i.e. around 260-280rpm for 20" wheel and 200-215 rpm for 26" wheel, both giving the same 15-16mph max)??

That is, in mixed terrain similar to flecc's tests where he achieved 25-30 miles or more on the Q, could a similarly geared 26" bike give the same range, or is there some inherent efficiency gain of a 20" over an "equally motor-geared" 26" wheel (besides the more efficient acceleration of a smaller, hence lighter, wheel already mentioned)?

If so, it would suggest that, all else being equal (e.g. controller software etc.) smaller wheels e.g. 20" could be the most suitable for the most efficient universal hub-motor ebike...

A direct comparison of Q and 26" bikes, e.g. Sprint, Wisper Works 905e for instance, seems unfair, since there may be weight and/or motor differences: e.g. the Sprint is slightly heavier (a few kg lighter rider on a Sprint would equalise that!), the Wisper is lighter (switch the riders!) and the motor powers of both are also likely slightly different, but on the same tyres & terrain they might give an idea if there is a real advantage to the 20" wheels of course, there may be a reasonable practical explanation for an efficiency gain, if it exists, (if you know of one, please let us know!!) and equally it may be a 26" wheel has the edge in more even terrain or can be engineered via motor control to equal the 20" wheel Q efficiency?

Here's some general pro's and cons for 20" wheels, as I see it:

+ smaller wheels are lighter so allow more energy efficient acceleration -
good for trips involving much starting & stopping e.g. at lights etc.

- small wheels = higher rolling resistance relative to larger diameter &
slightly bumpier ride?
larger front chainwheel = less ground clearance of lower chainline?

So, any ideas?

 

[JohnInStockie]

I can see what your getting at Coops.

There is definately something in the smaller wheeled bikes that seems to have an efficiency advantage somehow. In AtoB they had a large spread on the Moulton not long ago which was very interesting reading for me having never heard of them. In the Moulton design stage they had done some tests on different size wheels and found that 20" wheels were very efficient indeed, and went with them to produce what was aguably the best folder in the world.

Adding the hub motor brings in all sorts of extra complexities I think and maybe changes the efficiencies again in some way. Certainly having the capability to use normal gears and a large gear range is critical though.

 

[flecc]

The wheel size is a bit of a red herring. The reason it's the Q bike is because of the characteristics of the Quando motor. If it had different internal gearing to run at legal speeds in another wheel size like 26", it would be just as good.

That motor has a combination of a high power output, 576 watts gross, and a good torque curve shape, meaning it has a spread of low down power suited to hill climbing, making it rather special. Most motors aren't nearly as good in this respect.

Bike weight is incidental to some extent. Manufacturers use various dodges to produce a headline weight, such as making frames very small, weighing the bike in the minimum mode without mudguards, carrier lights etc. Check the spec on the 805e and the Quando John, and you'll find the 805 is sold with a minimal setup, while the Quando has everything, wide mudguards, heavy duty carrier, lights, bell, two leg stand etc.

As remarked above, rider weight is much more relevant.

Basically, if you want to produce a Q bike equivalent, you need to start with something rather special in the motor department, and that's rare. The bike part can often be sorted afterwards, but a poor motor can't be rectified.
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[coops]

The wheel size is a bit of a red herring. The reason it's the Q bike is because of the characteristics of the Quando motor. If it had different internal gearing to run at legal speeds in another wheel size like 26", it would be just as good.

Do you really think so flecc? So you think such a 26" wheel bike would perform just as well, including the peak current draw on battery aspect, and get the same range as the Q in your terrain?

If so, my prepared post seems redundant, but I'll post it anyhow in case it prompts some more useful discussion :

In the Moulton design stage they had done some tests on different size wheels and found that 20" wheels were very efficient indeed

Thanks John, I think thats the crux of it:

A combination of more efficient transmission of legpower into wheel motion (large front chainwheel) plus lower energy needed to accelerate smaller, lighter wheels, appears to make the 20" wheels "easier" to pedal, despite slightly higher rolling resistance (which is greatly helped by low drag tyres like the marathon pluses on the Q).

The easier it is to pedal, the more help you can give the motor exactly where it needs it most i.e. when accelerating and hillclimbing, and the resulting conservation of battery energy means the motor in turn can help you run for a longer distance/time that was mentioned by flecc in the article - the lower peak current draw on the batteries due to pedalling reducing the motor's load, allowing better performance from Li batteries on hills.

So maybe hub motors in smaller e.g. 20" wheels work more efficiently because the bike is set up for better harmony/synergy or complimentary assistance of leg and motor power: less a hybrid of leg "or" motor, more a synergy of both working together in conjunction simultaneously. No wonder flecc's having such a blast on the Q bike! It really seems to be the true "bike rider's" electric bike AND its so flexible in functionality into the bargain.

It shows the importance of factoring both human and motor elements into good ebike design - a holistic approach, if you like: to ensure all parts work together to give an overall performance greater than the sum of the parts; even then, personal differences mean each bike really should be individually tailored for best results, as flecc also said; but it certainly does seem that the smaller wheels are a template for efficient hub ebikes.

Next questions: what's the best wheel size for efficiency? Moulton said 20"? The Q chainline looks a bit low with the large front chainwheel and I'm concerned about ground clearance on rough ground: come to that, how practical is a 20" wheel on rough/bumpy tracks? Could the universal design be used for minor off-road routes, like bumpy,stony & uneven tracks - even with front/rear/full suspension? That would be great! Would a larger 22" (?) or 24" wheel still be an efficient "go anywhere" bike and manage off-road too?

Stuart.

 

[flecc]

Sorry Stuart and John, but the larger wheel is always more efficient in a given circumstance. That's a physical absolute.

Alex Moulton only showed that small wheels can be efficient, he didn't show they were more efficient, and they can't be. That's why race bikes always use the largest 700c wheel size or similar. The wheel mass is irrelevant, as it can only affect acceleration very slightly, and that's a minority activity in cycling.

What we are speaking of here is hill climbing, something not widely understood, but very thoroughly understood in cycle design. No road is perfect, and progress is over a series of ripples. On each depression the wheel drops into it, and must then climb out of it. The smaller the wheel, the steeper the hill that needs to be climbed to get out of a depression.

The Quando motor would be a better performer in a 26" wheel if it were suitably internally geared, and even better in a 700c.
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[JohnInStockie]

Flecc - Theres never any need to apologise for correcting a misunderstanding, although there is one situation where smaller wheels do have the advantage though, and thats when you pick up the bike to carry it.

I dont disagree (I cant!) with what you have said Flecc, it just seems that these smaller e-bikes have something the bigger boys dont have. From the info I have read, it seems that nearly all of the smaller wheeled bikes are generally better at hill-climbing than the larger wheeled ones, I understand this to be something to do with the torqe on the wheel?

If generally smaller wheels are better for the same motor at hill-climbing, and they can also power to the 15mph, then if they are given an ecellent gear range at the top-end, they (in theory) should be fast as well as flexible too shouldnt they?

Isnt that exactly what you have proven Flecc?

 

[flecc]

No, the smaller wheel bikes aren't better hill climbers John, that's the red herring I referred to. The only thing that matters in this context is the gearing. With a motor, that's the gear ratio between the rotor and the road surface, and with a rider, the gearing between the rider and the road surface.

The intermediate means are not material, except in as much as they add inefficiency, and in this context the small wheel is marginally less efficient. Hence the use of large wheels where efficiency is important. In the Tour de France, riders are free to choose bikes suited to each stage. For the time trials they use carbon disc wheeled bikes for example. If small wheels were better for climbing, they'd use them in the Alpine stages, but they don't, precisely because the larger wheel is always better.

I've only mentioned the way in which road irregularities produce a permanent hill climb simulation, but there's also the matter of bearing friction and grease/oil drag. A small wheel turns faster, so it's less efficient on both those counts.

I haven't in any way proved small wheels are better for performance, only mentioning how they aid load carrying due to the low centre of gravity, and can be useful in towing by providing a lower hitch point, so they have minor utility advantages.

What I've shown is that by taking the best available motor, and then improving the donor bike's efficiency as much as possible, a really good performance can be achieved. But it's important to note the Quando was already the best legal full speed hill climber anyway, but without rider gears the rider couldn't aid that. By adding efficient rider gears, the already best hill climb performance has been increased to well beyond the usual standard of e-bikes. If there had been a 26" wheel bike with the Quando motor geared to achieve the identical speed of the 20" Quando, I could have made that more efficient.

I'm at a late stage of a performance project on the 28" Torq, so I have no small wheel bias in that respect. The fact is that as I well remember at the time, Alex Moulton had a "bee in his bonnet" which no-one else in cycle design shared. It wasn't about folding bikes, which he didn't even consider at the time, but just a notion that a small wheel would produce an aerodynamically better bike, even to the extent of enclosing one in a sort of aero fusilage! It was a crazy flawed notion. However, by showing that 20" wheels could get somewhere near 26" and 28" ones for efficiency, he did open the door for folder designers.
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[coops]

@ flecc: You beat me to it answering . Re your earlier post, that's good to be clear about it: I was starting to think that the smaller wheel gave some additional advantage in hills. I agree about the "rolling" pluses of larger wheels - the great benefit of m+ on the Q shows up that limitation of smaller wheels which will be proportionately more highly disadvantaged by higher friction tyres.

In some ways I prefer a 26" wheel, and they're a more common size I think? Especially in MTBs.

I have other questions regarding motors: that subject has come up elsewhere recently, but since they're not directly related to the Q bike I may start another thread for those .

@John: Seems I was looking in the wrong direction both times i.e. not the wheel size affecting motor dynamics or the pedalpower transmission to a great extent, but the motor quality & gearing being important. I think what flecc is saying is that its not the wheel size that improves hillclimbing or torque, but having a quality motor suitably internally geared for the wheelsize: e.g. a quando type motor with lower internal gearing i.e. for 200-215 rpm in a 26" wheel giving same max speed of 15-16mph, may actually perform better overall than the 20" wheel, 260-280rpm 15-16mph Q (because they have equal gearing and torque for hills but a larger wheel always rolls more easily) - even if both bikes are equally chainwheel drivetrain geared for pedalling.

Now, what makes a good motor...? New thread for that I think .

Stuart.