Evomoto : a 235mpg streamliner

[visionary]

Congratulations Wolgang
Your detailed responses cleared up any doubts I had about the MPG claim, and the picture (of frontal area) was the perfect example of how you have achieved these results. I only wonder what would be possible with even more enclosed bodywork!
Your theory on the vehicle design (from your website) is excellent! I also believe in the importance of small aero-efficient single person vehicles, and how they can shape future vehicle design - you are very fortunate to be working in this arena.

I have a few questions I would like to ask:
Have you found a top speed for the evomoto?
Have you done any coast-down measurements in order to get drag figures?
Your website states about 10kg for additional weight, have you got a total weight figure?
Where does your instinct lead you for future developments?

[euromodder]

Originally Posted by visionary

Have you found a top speed for the evomoto?

From his German website : 130 kph / 81 mph

Your website states about 10kg for additional weight, have you got a total weight figure?

114 kg (250 lbs) with fuel
275 kg (606 lbs) all up - the innova can take rider + passenger

[skyl4rk]

I wonder how much of the fuel efficiency gain is attributable to a prone riding position and how much is attributable to the fairing.

[evomoto]

Good morning,

as euromodder already mentioned, weight is 114kg with fuel. Top speed is about 130kph (according to GPS). Concerning the weight, there are some reductions still possible. In fact, I did some redesign work on the seat undercarriage which has cut about 1kg. More could probably be done on other parts but I look rather for stability than for lowest weight, since 5kg less weight only help little with the fuel consumption at steady speed. During my round trip through Germany I had an additional weight of over 10kg and did not see significant influence to fuel consuption.
Concerning top speed, 130kph can be reached in flat terrain with no wind. Downhill or with tailwind you will see even higher speeds, however I don´t do this since I don´t want to overstrain the engine. Actually I limit my permanent speed to 110 to 115kph and use the rest only for overtaking. Oil temperature measurements have shown that at this speed I have optimum oil temperatures of 100 to 110°C. Running 130 kph at 32°C ambient temperature for 10min will kick the temperature up to almost 130°C which is more than I would like to see permanently. However mostly I keep a speed of 85 to 90kph and roll along with the trucks (not using the slipstream advantage - I keep a distance of usually 50m because I feel more comfortable this way).

I did do coast down and steady downhill slope coast speed measurements with the original Honda Innova and the evomoto. Results for cd x A are:
Innova: 0,57m2 for the upright rider and 0,42m2 for ducked down rider
evomoto: 0,23m2 for the seat in upright position and 0,21m2 for the seat in reclined position (which I use 99% of the time)
All results with rather tight fitting textile motorcycle protection wear.
I would love to go into a wind channel one day, but this is very expensive.

I calculated that there are pretty equal contributions to the improvement of the aerodynamic drag both from reduced frontal area and coefficient of drag. As a rough numer, it can be stated that both individual values (cd and A) dropped from 0,7 (original Innova) to about 0,45 (evomoto 125cc).

Apart from minor changes to the evomoto 125cc my thoughts for future developments go in different directions:
1. Go electric - it must be an incredible feeling without the sound of the combustion engine only with the humming of the electric motor. I do get an idea about this, when I let the evo go downhill with the engine in idle. It´s great especially on a windig road - uncomparable to anything I´ve done before. Hopefully, battery technology keeps on improving like in the last 5 years and we will see reasonable prices and capacities within the next 5 years.
2. Go for more power - I´d like to try out and use the good aerodynamics rather for top speed than for fuel consumption - of course the latter will still be good. My precalculations show, that with a bike with a top speed of 275kph you will still get a fuel consumption of about 100mpg at 130kph constant speed.
3. Go for more weather protection - this is what many people have asked for and suggested. From a motorcyclists view, I think weather protection is already great, but of course from the car drivers view it could be much better.

Greetings from Germany
Wolfgang

[NeilBlanchard]

Weight is secondary to aerodynamics, and drivetrain efficiency is the key. Both this project and the Jacobs project, and Dave Cloud's Dolphin and The Illuminati 7, all demonstrate this.

[evomoto]

Hello there,

Neil you´re right about both drivetrain efficiency and the weight. That´s why I chose the Honda Innova as the basis and, so far, did not bother about 5kg more or less. The latter is especially true for constant speed.
For acceleration, less weight is of course better, since the vehicle will be more agile when it´s light. And for deceleration it´s of course good to have less weight too, since you´re loosing less energy when braking. So weight is very important especially in urban traffic - for acceleration and fuel consumption.

There is another important influence of weight to fuel consumption which I think may not be underestimated. I got to this insight and conclusion yesterday during a 600km ride to my parents and back home. The autobahn was partially very hilly, partially absolutely flat and I got into several traffic jams. In the flat sections I thought about increasing gear ratio even higher but in the hills I was happy to have enough uphill-stamina.
So here´s my chain of thoughts:
1. For best fuel consumption, you want to run the engine with best possible efficiency.
2. This usually means you need to increase the engine load (torque) and reduce the revs.
3. You do that by increasing the gear ratio.
4. However, if you do that, acceleration of the bike will get worse.
5. Of course you can, for better acceleration shift down but it´s annoying and with only few gears (4 in the Innova powertrain) you will end up at high revs in the lower gear.
6. So if you want to have a certain acceleration level in the highest gear, you may not exceed a certain gear ratio.
7. This is where the weight comes into play: since acceleration is force at the wheel divided by weight, you will have more acceleration if you decrease the weight.
8. So if you decrease the weight, you will be able to further increase the gear ratio and still reach the desired level of acceleration.
9. The higher gear ratio will then run the engine with more efficiency and fuel consumption will be lower.

I hope I was able to explain.

By the way, you can find my fuel logs at the spritmonitor website ( www . spritmonitor . de ). Unfortunately I´m not yet allowed to post links, but you can find the evomoto 125cc quite easily by searching for the Honda Innova.

The values are in liters / 100km but it´ll give you an idea about my everyday fuel consumption. Overall fuel consumption so far is 1,12 l/100km which is equal to 205mpg. I have added comments (in German) about ambient temperature, wind speed / direction as well as the route - the most important "external" factors for fuel consumption. Lowest fuel consumption so far was 0,96 l/100km which is equal to about 244mpg. Please note that the spritmonitor site will not accept fuel consumption values below 1 l/100km, this is why I sometimes artificially increased the fuel data to meet the 1,00 l/100km limit.

Greetings from Germany
Wolfgang

[euromodder]

Originally Posted by evomoto

By the way, you can find my fuel logs at the spritmonitor website ( www . spritmonitor . de ). Unfortunately I´m not yet allowed to post links, but you can find the evomoto 125cc quite easily by searching for the Honda Innova.

I posted it in the first message of the thread, but here it is again for convenience
Details: Honda - Innova - evomoto 125cc - Spritmonitor.de

Please note that the spritmonitor site will not accept fuel consumption values below 1 l/100km, this is why I sometimes artificially increased the fuel data to meet the 1,00 l/100km limit.

Maybe you could ask them to lift that limit, certainly for small displacement motorcycles and mopeds.

Coming from people like you who really can get under 1 L / 100km (over 235mpg) they might more easily be inclined to grant such a request



The Honda Innova / ANF 125 is clearly a nice machine.
About half its users are reporting 2 L/100km or less (117 mpg or better) !

[evomoto]

Ups, indeed you did. Sorry that I forgot that and thanks for posting it here again.

I asked spritmonitor to allow also lower consumption values but got no response from them. Well, not a big deal, I can live with it.

The Innova is a very economic bike. When comparing the Innovas on spritmonitor to the evomoto, keep in mind that most users usually go much slower than I do. That´s how they get to consumption values of 1,8l/100km and even less. If they went 90kph on the autobahn , they would most probably get up to values of 2 l /100km as I did, when I tested my Innova in the original trim.

[Piwoslaw]

Evo, what driving (riding?) techniques do you use? Do you keep a steady speed, or pulse&glide? Do you kill your engine while coasting?
Do you have special tires? Are there even LRR tires for motorcycles?
Any instrumentation, like a vacuum gauge? I read that there is nothing like an OBD standard for motors

[skyl4rk]

I believe the Innova has a transmission similar to the Honda Cub or CT70. There is no hand clutch, you just idle down and shift.

I have been looking at available used small cc motorcycles but they all have a hand clutch. Eliminator 125, GS 250, DR 350 are a few types that I have found for sale in my area. I have not seen a CT70 for sale for a long time. I guess one could replace the CT 70cc motor with a Lifan 125.

Is there a way to convert a bike with a hand clutch to a prone riding position? The challenge is that you have four things that need to be managed by hand:

throttle
clutch
front brake
rear brake

It would be nice to be able to ride and control the vehicle either upright or in the prone position.

In the upright position you could operate the rear brake as usual with the left foot. But in the prone position, how would you do it?