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Discussion Starter · #1 ·
My sincere greetings to the forum members and greatest respect to those who manage to bring e-conversions to life!

No books and forums can replace the actual experience of people who have hands-on experience in making conversions. Thus, albeit my theoretical study indicates that Ducati Monster e-conversion is possible, please have a look at the desired specs - do you consider this doable in practice?

Specs:
1) max hp within the range of 43-53 hp
2) max torque within the range of 33-48 kW
3) weight of conversion components (motor+battery+controller+cooling unit+charger) below 60 kg (132 lbs)
4) max milage of 50 miles of aggressive city riding (full throttle - full stop cycles)
5) single drive (no gearbox)
6)max price of components below 4k USD
7) max speed of 100 mph
8) solid torque from the very beginning (1/4 mile in below 12 secs)

Beforehand I had experience with projects that looked good on paper but were not doable in practice. If you have any ideas/experience - please-please-please share it here.

Moreover, if you have in mind (or for sale) a ready set of components that have been tested together - please share it here!

Many thanks in advance guys!
 

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Discussion Starter · #3 ·
Dear Tomdb,

many thanks for your prompt reply.

you've proven my worst suspicions - motors I've been checking were much cheaper. I've studied both elmoto and electromotorcycleforum - those guys've been experimenting in different directions, cannot combine it into one project...

From your experience - do you think I could get the desired specs by increasing max price up to 6k usd? Will have to postpone project until all the original (gasoline) bike parts are sold - still better later than never.

I could also sacrifice 10-20% of max speed. But acceleration shd be comparable to 400-600cc bike, has to be single gear and minimum mileage cannot be reduced.

Do you think it's doable?
 

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Are you located in the US?

Because you would have to get it certified to be used on the road.
Also your location might affect availability of parts.
 

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Discussion Starter · #6 ·
Luckily I will not have those certification issues in the first year or more - we have no specific regulation regarding e-vehicles.

As for the parts and suppliers, I've checked out several options - Asia, Europe and US. I am a complete newbie to the e-conversions. I want to stick to US suppliers like thunderstruck-ev. They seem to have more experience - hence less worries about matching components, as well as more trust in the quality of components.

Delivery is not a problem - friends can help.

My approach is very straight forward: I want to convert a 400-600cc bike and get specs similar to a gas bike. I could sacrifice max milage and max speed for the sake of eliminating gearbox.

Topic of e-conversions appeared to be much more sophisticated than I expected - more study discovers more pitfalls. Do not want to end up with lots of time and money invested - just to discover that the desired specs were not achievable.

That is why I am asking experienced builders whether my aim is practicable.

Again, many thanks for your input! Much appreciated.
 

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So you are in the states?

150 Wh/mile is a good basis to use for battery sizing.

This means atleast 150wh*50miles/1000(wH to KwH) = 7.5 KwH of battery.
Using nissan leaf modules (cheap and avlaible) to get this energy would take 15-16 modules resulting in 110-120 volts 66ah and 60kg.
However this would cost roughly 2500 dollars (assuming 150 dollars/module).

Which model of monster you got?

I would set the finished bike weight target at around 200kg (less then the biggest monster with fluids)
 

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Discussion Starter · #8 ·
no, I'm pretty far from US - I move a lot, but bike will be most likely docked in Thailand.

I have two donors available - 2nd gen M400 and M600 produced in early 2000-s. In my opinion these are the best city bikes - their seat height is way lower than of Monsters of later years. Makes them versatile.

My friend has a hobby of making toys like 996 with 1098 engine. This involves lots of planning and engineering, but the outcome is fantastic - with original chassis bike handles great both in the street and on track. Key is proper reinforcement of frame and sticking to the original weight distribution. That's why in my target specs max weight of all components shd not exceed 60kg - so that my friend could do a job he's familiar with.

So your advice is ME1302 with leaf modules? this makes 2.500$ + 2.500$. Plus maybe another 1.000$ for smaller parts and tools. Total of 6.000$ and bike will fit into desired specs?

Thanks!

Btw. Recently visited Netherlands for track days and sightseeing later on. Was very much impressed - indeed one of the most admirable countries Ive visited lately)
 

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That'd actually be a pretty decent setup if I were doing it again today.

The Motenergy water cooled motor (save your original radiator and mounting brackets), Sevcon controller, Leaf batteries and a decent lithium charger (I like DeltaQ because they're sealed and they're programmable).

Go as high a voltage as the controller takes, you'll be glad you did.
 

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You realize that the electrical components are one story.

In a ducati the engine is stressed so this means you need to replace the engine with a mounting frame for the batteries and electronics.

Something like the bike attached?

Wonder if anyone got one of these working, they look easier to program than the sevcons. http://www.goldenmotor.com/HPC%20Series%20Controller%20User%20Guide.pdf
 

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"converted" the bike model i grabbed off grabcad. Switched out the frame with an more accurate one. Biggest issue right now is, leafcells are too wide to fit horizontally, this means they need to be grouped vertical then stacked. :(
 

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an example of the stiffing frame/motor mount. These will have to be very substantial, so alot of material and milling. Thus the "brackets" and other parts wont be cheap.
 

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Looking good for meeting the OP's requirements with the exception of the weight. So the total weight of conversion components would be around 85 to 90 kg? This would also have a bit of a negative impact on acceleration.
 

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No clue on what the actual torque curve is for the motor, so I could not calculate it.

However, I doubt that removing all the ICE components and replacing them with roughly 100 kg of electric will yield a weight difference of more then 20-30 kg.

So just go on a diet. :D
 

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Discussion Starter · #16 ·
wow! thanks for the renderings!

still the key issue - fitting into the desired specs is not clear... as for now, all the proposed designs have not been actually manufactured and tested, so no idea what the final specs wd be... will try to do more maths this weekend.

for ex http://www.goldenmotor.com/eMotorcycle/Dall-Antonia-Luigi.jpg is saying that Italian bike runs 150kmph with a range of 90km. But actual website of the maker http://dallantonia.com/dallantonia.html is showing less ambitious numbers:
Max. 105 KM / ha 150 km / h depends on the ratio
Shooting 0-100 from 4 to 10 seconds it depends on the ratio
 

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Discussion Starter · #18 ·
Hello again to all the Forum Members,

it took me much longer than expected to understand the maths and physics behind engineering a bike). Still in process, and there's a question i cannot understand - maybe you could help?

I want my bike to have a comfortable cruise speed of 160 kmph. Calculation shows that I would need 45 hp / 33 kW to maintain that speed.
At the same time most of the motors I see in the market have 10 kW constant / 30 kW peak power.
Does that mean that my bike would be able to move @ 160 kmph only for 5-10 minutes of motor's peak power? And cruising speed would be around 90-100 kmph (thats the speed with 10kW)?

Is my maths wrong?

Thanks in advance!
 

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I got roughly cruise of 25KW.

with 250kg total bike
0.7m^2 frontal area
Drag coeff of 0.6, might be alil low for the duc monster

So I would redo your calcs.
 

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Discussion Starter · #20 ·
my calc was very straightforward:

required hp = K * F * V^3,

where

K characterises aerodynamics == 0,065
F is the frontal area of bike + rider sitting straight == 0,576
V^3 is desired cruising speed power 3
sum is divided by 3500 in order to bring to kmph

then we multiply result by the efficiency of drivetrain of 0,9

The precise result is 51,42 hp or 38,08 kW.

Also - my Monster 400cc does go 160 kmph with no fairings and me sitting straight. Its specs are 43 hp 31.3 kW (Ducati is rumoured to indicate power on back wheel, not crankshaft). So I was thinking I was on the safe side with calcs.
 
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