Starting 2009 Honda CRF450 Build

[TysonScott]

I got a pretty sick 2009 CRF 450 Roller for 1000, it has new suspension internals and rims/hubs. Its also power coated black which looks pretty cool. Im looking to convert it to a high power electric bike. Im going to try and make it as powerful as the stock 450 (55hp). For my range and speed im hoping about 90-100mph top and 40-50miles range at like 25mph. Cause honestly most of the time im just going to be riding trails with friends. I realize this is very ambitious but i feel like I can do it. The guy i bought the bike from said he will laser cut parts for it if i need.

Questions:
How much power can you realistically get from a me1507, I've heard that it really under preforms and other people say its exactly like the 75-7. Does going to the 1616 increase performance much more with the water cooling.

Is my 40-50 mile range even possible while keeping the bike under 250lb?

Im thinking about getting a 200-300$ 3d printer for this project, if i make a mount for the motor/battery and other things will i be able to send in that file to be made in metal?

If the me1507 is not a good option, what are some other options? ive heard of the m force motor and the 75-7 but cant find a source for either.

Does the motor mount have to connect to the swing arm? i forget what that axel thing is called but I've seen some builds that connect and some that don't.

 

[speedy1984]

https://www.instagram.com/p/CbAfeeVtkGu/

Awesome bike there fella :thumb: Im also building the same 2010 450 crf and with a black frame lol.My build is for enduro and more bouncing over logs with bursts of power,so aiming for only 32 kw ish but a good size battery for ride time.Keep the posts coming :wink:

 

[amberwolf]

For my range and speed im hoping about 90-100mph top and 40-50miles range at like 25mph.
<snip>

Is my 40-50 mile range even possible while keeping the bike under 250lb?

Wh/mile, range, is going to depend on a bunch of factors.

If it's all continuous flat street riding with no hills, no wind, no stops/starts, and nice roads, well-inflated tires, etc., then you could probably get by with a fairly small battery; it would probably take 30-40wh/mile (maybe even less) to do that at a constant 25mph. (so 25mph * 40wh = 1000wh, 1kwh). That's not all that big or heavy.

But if you are riding on dirt/gravel/mud/sand/etc., on hills, slowing down/speeding up, etc., then the total weight of the system makes a big difference to how much power it will take for each mile, and so do the actual conditions and usage. You might use up to a few times the amount you would in the "perfect" scenario above. That starts getting pretty big and heavy, potentially filling up the whole former-engine-space.


Another factor is the power the motor system will need to do 100mph, or perform as desired under whatever your worst case offroad conditions are. If it takes a lot of power, you may need a larger battery than your range needs dictate just so the battery can supply the power without excessive voltage sag or internal heating.

Need to know more about the power levels required, etc., to figure out what battery you would need (since it has to supply everything that the rest of the bike uses, it is the last thing to figure out as doing that relies on information about evertyhing else on the bike and it's usage under what conditions).

 

[TysonScott]

For my range and speed im hoping about 90-100mph top and 40-50miles range at like 25mph.
<snip>

Is my 40-50 mile range even possible while keeping the bike under 250lb?

Wh/mile, range, is going to depend on a bunch of factors.

If it's all continuous flat street riding with no hills, no wind, no stops/starts, and nice roads, well-inflated tires, etc., then you could probably get by with a fairly small battery; it would probably take 30-40wh/mile (maybe even less) to do that at a constant 25mph. (so 25mph * 40wh = 1000wh, 1kwh). That's not all that big or heavy.

But if you are riding on dirt/gravel/mud/sand/etc., on hills, slowing down/speeding up, etc., then the total weight of the system makes a big difference to how much power it will take for each mile, and so do the actual conditions and usage. You might use up to a few times the amount you would in the "perfect" scenario above. That starts getting pretty big and heavy, potentially filling up the whole former-engine-space.


Another factor is the power the motor system will need to do 100mph, or perform as desired under whatever your worst case offroad conditions are. If it takes a lot of power, you may need a larger battery than your range needs dictate just so the battery can supply the power without excessive voltage sag or internal heating.

Need to know more about the power levels required, etc., to figure out what battery you would need (since it has to supply everything that the rest of the bike uses, it is the last thing to figure out as doing that relies on information about evertyhing else on the bike and it's usage under what conditions).

I guess just want about as much range as i can get without making the bike absurdly heavy, my budget for a battery is around 1200, do you think that will be enough to get the right cells and bms or buy a ev cell on ebay? also i was looking more into the motor controller combo and was wondering if the Kelly 8080I would be compatible with the 75-7 motor? im pretty sure it is i just wanted someone else to confirm that.

 

[Millhouse_5]

I may not be super experienced in motors yet, but I do know a thing or two about batteries.
With your needs of having range at a reasonably low speed, then the numbers stated above are pretty accurate, but obviously, more range is always better.

https://batteryhookup.com/products/100-brand-new-lifep04-32650-3-2v-6000mah-cells
Those cells from battery hookup are are very good value and support 3c continuous discharge and 10c discharging for 10 seconds. So even if you make a very small 24s2p with these cells at 900wh of battery you'll be able to put out somewhere around 8kw for a few seconds. So those cells should meet your needs and budget requirements just fine, all that's left is to consider your space requirements and max out the amount of battery you can fit.

 

[skeetab5780]

sub'd Nice bike! I'm doing a similar build on a 2003 CRF230F frame. You do not have to bolt the motor thru the swingarm thru bolt, but alot of the newer QS motors mount this way since its a good idea to keep the output shaft as close to the pivot as possible.

Don't you need like a special encoder or controller for the ME1507 IPM motors? Do they have regular hall sensors, I thought they were different and a pain?

 

[TysonScott]

I may not be super experienced in motors yet, but I do know a thing or two about batteries.
With your needs of having range at a reasonably low speed, then the numbers stated above are pretty accurate, but obviously, more range is always better.

https://batteryhookup.com/products/100-brand-new-lifep04-32650-3-2v-6000mah-cells
Those cells from battery hookup are are very good value and support 3c continuous discharge and 10c discharging for 10 seconds. So even if you make a very small 24s2p with these cells at 900wh of battery you'll be able to put out somewhere around 8kw for a few seconds. So those cells should meet your needs and budget requirements just fine, all that's left is to consider your space requirements and max out the amount of battery you can fit.

how do you determine the maximum kw that the battery can support?

 

[Millhouse_5]

The KW will be a mostly fixed constant for any given battery with the same cells.
In this case - 3.2v multiplied by its max current of 18A (3C) gives 57.6 watts per cell. Multiply that by 48 cells in that theoretical pack to get 2.76Kw continuous. Repeat the same calculations but use the 10 second load max of 10C to get 9.22Kw.

That is of course under specific circumstances and I don't know how much the voltage will sag under a 10C load, so 8kw is a reasonable assumption for these cells in that configuration.

The higher AH pack you make, the lower the C rate will be for a given wattage, so there will be less voltage sag.
The higher the voltage you pick, the lower the C rate will be for a given wattage, so there will be less voltage sag.
So every cell you add, no matter what configuration, will give you less voltage sag and more wattage.

Most people stay within the 72v-96v range and I picked 72v (24s) for that theoretical pack in my example above.
I prefer high voltage personally to keep the current low and therefore allow the controller to be a lower amperage and also keep from needing larger than 0 gauge wire to support massive current draw.