Building Trial Bike from Vintage frame

X

Xpongebob

10 mW
Joined
Oct 29, 2013
Messages
22
Hi, E-gentlemen,

First of all, let me introduce myself : I am a 29 years-old frenchman living in the south-west of France. I've got a good knowledge of conventionnal mechanics, owning myself a Norton Commando, some Bultacos, etc...
But I am totally ignorant on electric motion !
I saw an electrical conversion of a Fantic trial bike that triggered my want for an quiet trial bike in order to stop bothering hikers in the wild. That's why I recently bought myself a Fantic 240 Pro :



That I intend to convert. For the time being, I got hold of a 48V LMC 170-127 motor which was a decent deal.
Now I have some equations to solve :

- Would 48V 60 Ah battery be adequat ?
- What gearing should be used ?
- What type of controller should I use ?

Given that I'm not in need for speed (40-60 km/h are enough), Torque is important, and above all I need around 40 km range off-road style.
I didn't find any "builder guide", and trial bikes are not usually what people convert.

What do you think ?

Regards

Xavier
 
welcome to the forum Xavier,

interesting build, please keep us updated..
is this the video you mention:
[youtube]CMBkndF-TJc[/youtube]

if gwhy!or betarambo see this thread they will likely have some advice for you..
best luck :)

here are some threads for inspiration, in case you haven't already seen them..

http://endless-sphere.com/forums/viewtopic.php?f=12&t=23179&p=765754&hilit=CMBkndF+TJc#p765754

http://endless-sphere.com/forums/viewtopic.php?f=12&t=32042&start=125

http://endless-sphere.com/forums/viewtopic.php?f=3&t=41746&start=15

http://endless-sphere.com/forums/search.php?keywords=gasgas

http://electrictrials.com/forum/
 
Xpongebob said:
That I intend to convert. For the time being, I got hold of a 48V LMC 170-127 motor which was a decent deal.
Now I have some equations to solve :

- Would 48V 60 Ah battery be adequat ?
- What gearing should be used ?
- What type of controller should I use ?

Given that I'm not in need for speed (40-60 km/h are enough), Torque is important, and above all I need around 40 km range off-road style.
I didn't find any "builder guide", and trial bikes are not usually what people convert.

What do you think ?

Regards

Xavier
Click to expand...

Hi and welcome,

- Would 48V 60 Ah battery be adequate ? yes,, but greatly depends on gearing.
- What gearing should be used ? aim for a loaded top speed of around 30mph initially then adjust the gearing (up or down ) to get the torque ( limited by the current from your controller can supply ) you want.. the lower the current of the controller can supply then the slower the gearing needs to be ( its a trade of between speed and torque )
- What type of controller should I use ? min 150A ( ideal 300-400A ).

This should give you the starting points...
 
Hi guys,

Sorry to answer so late, only saw your messages today...
It's been a while since the beginning of my project. First I had to learn how to weld !



Things are progressing slowly, but surely.

One of the biggest problem will be Battery pack sourcing as it is complicated in Europe to have these shipped simply.

Thanks for your answers, I'll keep you advised :wink:
 
Hi,

The best bang for the buck in large format lithium cells (30 Ah) are used Nissan Leaf modules (2s2p -7.2v nominal, 60 Ah) available for about $140 shipped. Check the links in my signature for more information.
 
Need to check these. Size will matter of course, and I was thinking pouch cells.

THX for the input
 
Hi,
Xpongebob said:
Need to check these. Size will matter of course, and I was thinking pouch cells.
Click to expand...
Each module contains four 30ah pouch cells.
 
This is getting really interresting Mitch ! I am reading the topic about these.

Thanks a lot

Xavier
 
I've been doing my homework, and after calling some people, it turns out that since battery packs are leased, theýre not available for sale nor for salvage in a junkyard.

Sooo, I've ordered a 48v60ah pack new from the US. It looks like it's the best deal for me.

Now for the numbers : I will end with an approximately 100kg bike, let's 180kg with the rider on.

Do you think a rated 5kw motor is up to the task ? My calculations tend to show it's a little bit short, but nothing's worth field test.

Another question, I have a LMC 170-127 motor which seems sturdy enough but not waterproof and am on the verge of buying a golden motor HPM5000B as it's supposed to be water resistent, any thought on that ?

Regards

Xavier
 
Here is a little update :

Battery box completed, controler holder on the way :

149595image.jpg


379470image.jpg



Should weight around 80 kg, 5kw motor, 48v60ah battery...

And still learning aluminium welding !
 
Hi,

I chose the Nissan leaf cell pack

http://hybridautocenter.com/HAC4/index.php?option=com_content&view=article&id=72&Itemid=631
 
So many things to do ! Trial and error design, no adequate tooling (lathe...) need to wait for a lot of different parts...

Today I have battery, motor, controller, throttle (magnificent set up by the way :wink: ), lot of sire to sold/connect,

And I am waiting for my jackshaft, my skid plate and a few special connectors for the charging set up.

Almost there !
 
all my builds have been trial and error... and the amount of time it takes to sort out each problem as you hit it really do add up, seems like you are almost there to power it up for the first time. Looking forward to some nice video !.. its something I should really do but I never find the time :D .
 
Just finished my battery case and harness !







Charging at 10 amps for a first attempt, seems to work fine, no heat at all.

I have halved the pack so as to charge it as 2 separate 6s2p packs, in the end, the contact Key will do the halving of the pack (it is a battery connector as found on boat batteries).

Cheers
 
And here is the full electrical setup, It work for sure, but throttle control seems to be just on/off, I'll have to correct this. Perhaps it's because motor has no load ?

 
Xpongebob said:
And here is the full electrical setup, It work for sure, but throttle control seems to be just on/off, I'll have to correct this. Perhaps it's because motor has no load ?

Click to expand...

8) I recognize that throttle box.. The only thing i can think of as regards the on/off nature for the throttle is that the throttle input on your controller may need a pull down resistor or there is a setting in the software for your controller to set the type of throttle and type of response. but yes it may also be the type of control that the controller does i.e the motor needs a load on it to work correctly this can happen with current/torque based throttle control.
 
Hey !

The controller software is pretty simple, but i'll wait until complete mounting be fore playong with Any parametre.

Cheers
 
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