[custom] honda ecrf 250r


Rashid510

Well-known member
Forum's Sponsor
Likes
1,127
Location
South San Francisco, CA
Was wondering the same thing.
This got posted up on electrek, theres also discussion about the bike there too. One piece out of the comments:

Zero ZF 75-7, Sony VTC6 @ 6.2kWh and ASI BAC8000

Being that its a Zero SR ZF-7 motor, could be either the wave spring washer is not seating correctly, bearings are starting to go out, or the chain slack. Also depends on the vintage of the Zero motor, theres two types (SMPM (surface mount) and IPM (Internal magnets and rotor design different). The SMPM motor is notorious for clunking and then breaking....
 

Mark911

Well-known member
Likes
1,123
Location
Corona Ca
I can almost (note the qualification) say that without a high voltage motor any bike over 15kws is going to be 20-25 lbs heavier than the Alta assuming similar sized packs. It’s just the nature of the beast.
 

Philip

Administrator
Staff member
Likes
4,045
Location
Lake Havasu City, AZ
I can almost (note the qualification) say that without a high voltage motor any bike over 15kws is going to be 20-25 lbs heavier than the Alta assuming similar sized packs. It’s just the nature of the beast.
What was keeping Alta from going with 400V, 600V, or 800V battery packs and motors?
 

Mark911

Well-known member
Likes
1,123
Location
Corona Ca
What was keeping Alta from going with 400V, 600V, or 800V battery packs and motors?

Isolation I suspect. 350v pushes pretty hard on every component in the high voltage system. Like a pressurized air cylinder, if the individual parts are not rated for the pressure (voltage) they'll be liable to fail (short). This could lead to a human safety situation and big liability. 350v rated components are still relatively cheap but costs and risk go up quickly at higher voltages.

Then you'd need to think about the battery pack implications. The series cell count would need to go up proportionally making the individual modules High Voltage as well. Now just building and/or handling an individual module could kill you! That would require additional collateral build costs. If you wanted to keep the cell count/capacity the same (for weight/size reasons, for example) a 600v system would require almost twice as many series cells? Ok, but now what about current? The only configuration possible would now be around 150 cells in series with only 3 cells in parellel. Is that enough?
 

Philip

Administrator
Staff member
Likes
4,045
Location
Lake Havasu City, AZ
Ok, but now what about current? The only configuration possible would now be around 150 cells in series with only 3 cells in parallel. Is that enough?
The voltage will double, but the current will be a half, so these 3 cells will be handling it the same as before. However, then Code 36 batteries will probably become pretty useless, perhaps even dangerous, unless you install a BCU that can manage 150 battery groups properly. But, as far as I can tell, our current BCU can't manage even the 84 groups very well.
 

Philip

Administrator
Staff member
Likes
4,045
Location
Lake Havasu City, AZ
Tesla Model S uses 16 module, each consisting of 444 individual 18650 battery cells in a 74p 6s configuration. No wonder I keep hearing that if a few of the individual cells go bad nobody will even notice.
 

Similar threads

Top Bottom