Battery Vehicle Society

As I said, I will be testing to find out, and I did intend to have a larger pack..My point was only that you could MAKE IT ROUND THE CIRCUIT with a bike the size of the aprilia...not that it would win against any competition.

At the lower speeds our bikes will be at I think the riders will approach it like they do 125cc racing, trying to maintain maximum velocity at all times. Most of the bends on the TT will be taken at greater than 50mph I believe.
For sure the winner will be the bike with best power to weight ratio, and enough battery power to use it all through the race...if such a beast yet exists!

I spent my early years racing bikes on track, so have some idea whats involed!:)
Steve

PHEV wrote:if such a beast yet exists!

The beast: http://www.evdaytona.com/
If you have the budget...

Wilfried

I reckon my Aprilia could make it at 50mph average as it stands

Slightly different from.

As I said, I will be testing to find out, and I did intend to have a larger pack..

Larger pack?

My point was only that you could MAKE IT ROUND THE CIRCUIT with a bike the size of the aprilia...not that it would win against any competition.

Maybe I've been reading you wrong, but I think you've shifted quite a way from the first statement.

The beast: http://www.evdaytona.com/

250Kg is a heavy bike and they only claim 51 miles 'street rodding'.

Evdaytona have been making promises for a few years. I've forgotten most of the details, but as far as I'm concerned the bike still falls into the 'Vapourware' catagory at the moment.

Come on chaps, this isn't the time to argue semantics

We should be pooling ideas and resources instead. Rumour has it those tea-spoilers across the water are putting together a team to try and show us who's boss. Can't have them winning the first EV TT, can we?

Oh how I would love to put a machine together for something like this but if we want to show the septics whose boss, the issue is, to paraphrase a well known politician, batteries batteries and batteries which means money money money! and with LiPo cells being good on performance and "fitability" into a bike but being less good on life and cost and safety than LiFePO4 and all the other permutations so often discussed in his forum, building a machine for this would have to be a case of a no compromise design for a hilly twisty race and again this brings cost. Ive got the workshop, the machine tools, the enthusiasm and a reasonable degree of skill (like so many others on this forum!) but not the money

So if anyone out there wants to give the BVS a wedge to do the race then I am sure the machine would emerge I for one would be up for helping but I suspect it wont come cheap!

If only they would allow streamlining, GRP and Ally is a lot cheper than Lithium!

Indeed Malc, I agree completly!
I don't know where all that came from tbh!
Crtisism like this tends to STOP people posting thier idea's...the better aproach Paul, would be to bring an entrybike that toasts mine and show me that way!

The physical size of the pack on that daytona is less than the aprilia! My guess is that thier specs are estimates of what they COULD achieve, not what they have. Thier bike seems about the same as Tod Kolins new gpr tbh, but with lower resistance batteries, and 10X the price:(

Thank you guys. We'll have words. Please shake hands and make up It's the taking part that matters

PHEV, your original statement was

I reckon my Aprilia could make it at 50mph average as it stands...

and your signature says

Aprilia RS motorcycle, 500A controller, Cedric's AgniMotor, LifeBatt batteries for 40 miles and 80mph top speed. 140kg

On that basis I dissagreed with you, 40 miles street does not translate into 38 miles track very well.

You then explained that you had a larger pack and gave some energy consumption figures.

I dissagreed with you again. I think the consuption figures on the track will be much higher.

You then talked about using a larger pack and I questioned the discrepancy.

I'm not acusing you of lying, or questioning your personal hygiene, I'm simply pointing out that 'as is' and 'larger pack' are conflicting statements. They change the basis of the argument (and I mean argument in it's propper sense).

Good grief, we'll make as little progess by never dissagreeing as we will if we never agree.

I'm sorry if my tone comes over poorly sometimes, but as I've stated many many times, I find writing a very difficult process, which is why you're unlikely to get many articles for 'Plugged In' out of me.

Getting back on track a bit (pun intended.....) have any of you tried to work out what the average power demand is for your bikes at various speeds?

I've done some crude measurements on my little Yamaha to try and calculate the rolling resistance (really simple stuff, measuring the tyre drag at low speed) and also the aerodynamic drag (easier for me, my other hobby is designing aeroplanes, plus I used to design parachutes years ago).

I've come up with a figure of just under 1kW for 30mph in still air on smooth, level tarmac.

Does this sound about right for an unfaired bike, on narrow tyres, that weighs around 95kg, with an 80kg rider in a fairly upright position?

I assumed a Cd of 0.65, which may be a bit optimistic.

What I'm trying to do is work out just how much energy is required to get around the IoM at various speeds. Memory Map has given me the elevation profile of the circuit, so knowing the weight of the bike I can calculate the hill climb power needed. Before I start, it would be handy to have confirmation (or otherwise) of my sums.

The power quoted above is output at the wheels, so needs adjusting for overall power train efficiency.

Jeremy

I can get hold of a brand new road legal cheap Chinese 125cc sports style bike for £600 + vat if you want a donor bike, ICE can be sold on e-bay to recoup some of the cost. http://www.eco-wheels.com/Sports/Kaiser%20XTR%20125cc/Kaiser_XTR_125cc_KS125-23.htm.

You never know, if I talk nicely to the importer the bike may be free and possibly some sponsorship money may ensue?

Howard