Back In A Currie: 06 Mongoose Review

[xyster]

Hi everyone. Justed signed up as I've been really getting into ebikes lately and currently looking at trying to put one together. Xyster, any chance of finding out how many teeth are on the large cog that's connected to the hub? I'm thinking of a similar design, but I need more speed.

Hi βεη. Little hard to see, looks like 23 or 24.

In greek letters, your name is "&#946 ;&#949 ;&#951 ;" without the quotes or spaces.

[knightmb]

Hahaha, no. Tried to write my name with beta, epsilon and eta, but didn't work, so I guess I'm stuck with just plain old Ben.

Yeah, if you put in βεη then it will try to convert it to the higher bit characters, but the database can only contain English characters, so you get that kind of stuff. I did for giggles just copy/paste it into the database for your username to see what would happen, it wasn't pretty.

You could always put it in your signature at least.

[Ben]

Hi [Ben]. Little hard to see, looks like 23 or 24.

Cheers. I was looking at the specs of this motor (250W?) on Unite's website and it seems as though to get 15mph, or 24km/h for all us metric lovers, the motor would have to reach ~3600rpm or 500rpm from the shaft. No load speed for the motor is apparently 3445rpm/480rpm. Doesn't seem to add up.

I found this graph at some website, the table matches up with Unite's site, the graph; not so much.

Edit: Deleted graph, same as shown here http://endless-sphere.com/forums/viewtopic.php?t=725

[TylerDurden]

Currie doesn't help things by promoting the MY1018 as a 450W motor... it ain't hardly.

Currie ships these with 30A controllers. Needless to say, motors get burned up.

Reid Welch made a good thread on cooling the motor to boost the power: http://endless-sphere.com/forums/viewtopic.php?t=525

[xyster]

Currie doesn't help things by promoting the MY1018 as a 450W motor... it ain't hardly.

Currie ships these with 30A controllers. Needless to say, motors get burned up.

Reid Welch made a good thread on cooling the motor to boost the power: http://endless-sphere.com/forums/viewtopic.php?t=525

It's a 35 amp controller. And it works great for me at 32 volts (~1000 watts). I drilled holes in the cover and attached a PVC elbow joint to pipe some wind inside. I still stop and check its temp every few miles, and back off the throttle when it gets too hot to hold my hand on. Not bad for $300. Me and my girlfriend can ride together now.... And I've still got my X5 for serious ebiking.

Reid fried his after 7 miles at something like 26mph (if I remember his post correctly). He didn't stop to take its temperature! And he lives in hot-hot Florida.

[Ben]

So has mongoose/whoever done any modifications to the motor, or are they just trying to flog it as 450W with a 35amp controller?

Also, does the sprocket on the motor have 9 or 11 teeth and does it use normal bike chain?

I'm seriously contemplating getting one of these motors and want to research every angle before I put my money down.

[xyster]

So has mongoose/whoever done any modifications to the motor, or are they just trying to flog it as 450W with a 35amp controller?

Also, does the sprocket on the motor have 9 or 11 teeth and does it use normal bike chain?

I'm seriously contemplating getting one of these motors and want to research every angle before I put my money down.

No, Currie is flogging an unmodified 250W motor. And I am willfully and deliciously flogging said motor further.

The motor sprocket is 9 teeth. Regular bicycle chain. I don't know the gearbox reduction -- but it's been posted somewhere around here....

[Ben]

Thanks for the speedy reply. The gearbox is 79:11. I suppose that means that if the second reduction is 24:9 the total reduction is 632:33. The motor must spin pretty fast then if the bike goes 15mph. I just hope there'd be enough torque if I were to reduce it less than that.

[vanilla ice]

New forum member here, and new Currie 450w rider also. I just wanted to say thank you to you guys for posting this information. I'll probably end up trying the hair dryer mod. Previously I was thinking about fitting an inexpensive water cooled Pentium4 kit to the motor. Now that I think of it, I'm not sure how well the motor gets the heat transfered into the zinc case. I think the blower idea would work better. Thanks again.