KR-E ...lectric

[bogan]

Have finally got my electric conversion of a KR-1 going, still some tweaking and testing required but happy with the progress. One design constraint I had was to make it look good, none of this square battery poking through frame/fairing BS, and I think I've achieved that









The specs:
Motor ME0708 brushed permanent magnet, 4.8kw continuous or 15kw for 1 min max.
Batteries 3 38Ah 12V AGM SLA
Controller alltrax AXE4844

Currently it's set up for 200A max, which is about half what it could do with better batteries. The rev counter has been replaced with an ammeter, and there is also a digital display with energy used and voltage/temps etc. The main electronics are in the tank, which has the bottom cut out of it. With the DC converter under the rider seat, and the charger going under the pillion with a 3 pin plug. The motor is mounted directly to the swingarm to maintain constant chain tension, it drives the wheel through a 14/62 reduction, I machined the 62 tooth sprocket to around 20% of its original weight.

The max speed so far is just over 50kmhr, hoping to better that when I get the rolling friction down a bit. Range unknown for that reason. One thing you notice real quick is the lack of engine braking (didn't see enough benefit to pay an extra hundy bucks for a controller with regen), basically every corner feels like one you have clicked it down into neutral instead of first, which is impossible cos it's got no gears. Which is why it's got the big e-stop on the tank, if the controller fucks out, the most likely outcome is the bike takes off All in all it's pretty entertaining to ride though

I plan to perhaps put a few crash bungs on it and set up car park gymkhana type circuits or something like that for a bit of fun (250gp bike turning radius on tight slow turns should be good for a few laughs). And once I've done a bit of testing and whatnot anyone can talk to me bout having a go on it too

[Dare]

Nice work! Looks like you kept the original look pretty much.
Got any other specs? How light is it now? Is 50kmh really its max speed?
And can we (I) see it nekked?

Would love to have a go, personally I'm still waiting for a couple more breakthroughs in battery tech (A123!)...
A few years of leccy GP should have that sorted

[banditrider]

Looking good dude - gonna see it on the FNR soon...

[bogan]

Nice work! Looks like you kept the original look pretty much.
Got any other specs? How light is it now? Is 50kmh really its max speed?
And can we (I) see it nekked?

Would love to have a go, personally I'm still waiting for a couple more breakthroughs in battery tech (A123!)...
A few years of leccy GP should have that sorted

can't find any good pics with the tank off, but if you zoom in on this one its a bit naked
weight is 147.5ish, with 10 more kg on the front than the rear. So with an original dry weight of 123kg, + bout 20kg of fluids, there isn't much difference, and all the weight is low as now. And not sure bout the 50kmhr, I calculated it would do around 70 unloaded, but I think the rolling friction is drawing so much power the battery voltage is sagging enough that it won't get near that top speed. Also, I could pop another battery to bring it up to 48V if needed, but I think I'll wait for some cheap A123's or similar, or wait till I have a job!

Looking good dude - gonna see it on the FNR soon...

only if the FNR calls in to see it, which would be good for a laugh once the crash bungs are on it

[rwh]

Nice

Although, I see far less point in going electric if you don't do regen - range vs battery weight seems to be one of the biggest issues with electric, and any chance to recover some of the juice seems to be a good idea to me.

Richard

[SMOKEU]

That's a pretty dope looking ride. Does it peel mean skids?

[imdying]

That kicks arse

[Swoop]

Very nice work! You should be proud of what you achieved.

I'll look forward to seeing further info on this project (range, etc) in the future.

[p.dath]

The feeling of not being in gear while going around a corner is interesting. It does sound like you might need the regen controller.

[bogan]

Nice

Although, I see far less point in going electric if you don't do regen - range vs battery weight seems to be one of the biggest issues with electric, and any chance to recover some of the juice seems to be a good idea to me.

Richard

yeh, it would be nice, but my budget didn't stretch that far so... also I'm not sure how mcuh juice you can pour back into an SLA, going by the batter recomendations, more than 10A would be pushing it, and that sorta current just ain't worth it.

That's a pretty dope looking ride. Does it peel mean skids?

nah, but the first few version had some mean smoke

The feeling of not being in gear while going around a corner is interesting. It does sound like you might need the regen controller.

It's only an issue if you aren't expecting it, like on a pushbike it's fine, not so much on a v-twin.

[rwh]

yeh, it would be nice, but my budget didn't stretch that far so... also I'm not sure how mcuh juice you can pour back into an SLA, going by the batter recomendations, more than 10A would be pushing it, and that sorta current just ain't worth it.

Interesting - I thought you could generally charge at just a slightly lower rate than discharge, but that's a long way from 200A

Richard

[R6_kid:Me]

The feeling of not being in gear while going around a corner is interesting. It does sound like you might need the regen controller.

Or be on the throttle. It sounds very much like at two stroke race bike, so you just need to adapt you riding to fit.

[bogan]

Interesting - I thought you could generally charge at just a slightly lower rate than discharge, but that's a long way from 200A

Richard

yeh, then again going by the battery recommendations I shouldn't really be pulling 200A out of it either next one will definitely have regen

Or be on the throttle. It sounds very much like at two stroke race bike, so you just need to adapt you riding to fit.

well it used to be a two stroke race bike

[k14]

yeh, then again going by the battery recommendations I shouldn't really be pulling 200A out of it either next one will definitely have regen

So how many A123 cells would you need? That would save a whole heap of weight too. I just got one for my race bike (a 4 cell) and it's 355g compared to the 2.4kg of the old SLA. Not sure on the capacity though, think they both are around the 4-5Ah range maybe?

Anyways, that is an awesome effort. How much did it cost for it all?

[bogan]

So how many A123 cells would you need? That would save a whole heap of weight too. I just got one for my race bike (a 4 cell) and it's 355g compared to the 2.4kg of the old SLA. Not sure on the capacity though, think they both are around the 4-5Ah range maybe?

Anyways, that is an awesome effort. How much did it cost for it all?

think it'd be about 60 of them, which I think would cost around 1500bucks atm. And a123 cells require a battery management system which is around 500bucks (though I'd probly try and make my own), motor was around 700 a few years ago, batteries 450, controller bout 450, another couple of hundy on misc bits, + a donor rolling frame obviously. So somewhere around 2K of parts, and hundreds of build hours...