OSET 20" lipo conversion

[stonezone]

So I recently got a 20" Oset bike and I'd like to replace the batteries to maximize the range for some trail riding but nothing extreme (I have a gasgas for that). Weight isn't a concern, more power would be fine but not a requirement. Mostly just extend the range to 2 hours or more of mellow to moderate flat trail and road riding (i'm 180lbs).

I am already familiar with LiPo safety, balancing and charge/discharge requirements (I've previously owned rc heli's and planes that I customized but never with more than one battery) so I know the risk i'm taking with building my own bank and the inherent dangers with this battery technology.

The motor in the Oset is 48v (i'm not opposed to replacing the motor either if that would improve things)

Should I just sell a bunch of stuff on craigslist and buy something complete from http://www.lifepo4.cc (suggestions?)

or build my own:

I was looking at using "Turnigy 5000mAh 6S 20C Lipo Pack" (better option?)
https://www.hobbyking.com/hobbyking/store/__9176__Turnigy_5000mAh_6S_20C_Lipo_Pack.html
(I also have a large parts list for connectors, cables, voltage analyzer, charger, PS, etc but i'll spare you)

What's the best configuration for combining them in parallel sets and then running them in a series to get the longest range. 2 in parallel and both sets running in a series (as the image shows)? Other options to extend range to the max. I was also thinking i could maybe build a duplicate setup and use a manual switch when the first one was low.

Finally i'm wondering on what to do about charging. I assume I'll have to buy a charger for each P set but I really don't know since i've never had any more experience than with just a single lipo (in planes and helix).

Sorry for all the n00b questions but I'll get it eventually. Great community here and an exciting time to be involved!

Aloha,

StoneZone

(PS, credit and thanks to GHY on the trials central forum for the attached image)

 

[gwhy!1]

Always parallel the small packs first and treat them as one battery ( charging and balancing ) always balance charge the individual lipos and make sure that the cells are in good condition before paralleling them with other packs , this has 2 major advantages, if something goes wrong with a cell then it will not destroy all the batteries in one go, only the paralleled ones, it also makes it easier for safe charging using 2 lipo balance chargers.

 

[Wishes]

I also come from the RC world and used Lipo's for a few years on my planes and heli's before I started to use them on my ebike for over a year now. I use the HK 6s 20c or 25c packs for my ebike, I have a few of both types. I also have an real ebike battery with BMS and lifepo4 cells.

Because of my battery placement and wiring requirements on my ebike, I have no choice but the make my serial connections first, then parallel those. Although it has been highly debated on the forum in the past, I do believe the general consensus is to parallel first, serial connect after as gwhy stated.

Something to keep in mind if you are debating between HK lipo's and real ebike battery with BMS.

HK lipos are worth it, especially if you are already equipped to charge them. But I have learned over time and experience that they do come with drawbacks used in ebike applications. They don't last as long versus a real ebike battery with cells connected to a BMS. Those cells tend to be better quality than HK cells and the fact that you are discharging with a BMS definitely contributes to the lifespan of the cell. So HK batteries, although cheaper of an initial investment, tend not last as long.

That being said. I still use HK lipo's in some cases. Best punch\capacity to weight factor out there.

Wishes

 

[stonezone]

Well I think I fried my controller yesterday on a longish ride. Engine locked up for a second, then went full throttle after I power cycled it and now no life. I haven't connected the batteries straight to the motor yet to see if it's ok but my fingers are crossed.

Any suggestions on a replacement controller that i can replace the oset with, or would not be a good time to upgrade? My next step is to go to some 24" wheels so I'm open to suggestions.

Here's one I found that seems similar:
http://www.monsterscooterparts.com/48vo12unscco.html

thanks!

 

[gwhy!1]

Well I think I fried my controller yesterday on a longish ride. Engine locked up for a second, then went full throttle after I power cycled it and now no life. I haven't connected the batteries straight to the motor yet to see if it's ok but my fingers are crossed.

Any suggestions on a replacement controller that i can replace the oset with, or would not be a good time to upgrade? My next step is to go to some 24" wheels so I'm open to suggestions.

Here's one I found that seems similar:
http://www.monsterscooterparts.com/48vo12unscco.html

thanks!

It defo sounds like the controller has gone, and the one you linked to will do the job as a replacement/spare or something to play with, or you may be able to fit a gng bigblock motor into the swingarm, If you are going 24's then I would consider a motor upgrade to the gng bigblock like bzhwindtalker is using in this thread http://endless-sphere.com/forums/viewtopic.php?f=28&t=57668&start=100

 

[stonezone]

will I lose any performance with that controller? hard to find full specs on it.

I wasn't able to find the exact GNG motor he's using, do you have any ideas on what would be good/comparable? I'd like to get a kelly and brushless eventually to get more flexibility....

Thanks as always

 

[gwhy!1]

will I lose any performance with that controller? hard to find full specs on it.

I wasn't able to find the exact GNG motor he's using, do you have any ideas on what would be good/comparable? I'd like to get a kelly and brushless eventually to get more flexibility....

Thanks as always

yes you will prob loose performance but for that price its worth the gamble as you can allways do a shunt mod of the controller to try and up the performance again or you can jump straight in and buy a kelly brushed controller with a much higher spec but also a much higher price tag but at this point you need to make a decision which way you are going to go, you dont want to spend a great deal of money on a brushed controller if you defo what to go brushless in the not to distant future but a brushless motor and kelly controller will prob set you back $200-$300 plus the time to fit it into the oset. Have a word ( PM ) LightningRods he seems to know where to get them from, or PM bzhwindtalker ask him where he got his from.

 

[efMX Trials Electric Freeride]

bzh is using the BHT motor (w/ kelly controller)..
its similar to the gng but not the same motor..
http://bht-bike.com
http://e-bike-diffusion.com

It defo sounds like the controller has gone, and the one you linked to will do the job as a replacement/spare or something to play with, or you may be able to fit a gng bigblock motor into the swingarm, If you are going 24's then I would consider a motor upgrade to the gng bigblock like bzhwindtalker is using in this thread http://endless-sphere.com/forums/viewtopic.php?f=28&t=57668&start=100

 

[bose]

You could always get a spare controller straight from OSET.

I am running my OSET 20.0 with two 12s3p paralleled Sony Konion VTC4 (NEW genuine cells) packs, a bit over 12Ah. If you go the route of konion cells I would suggest going at least 10p (opposed to 6p for me) for longer life. The weight saving from the lead batteries is amazing and it's a much better ride.

 

[stonezone]

yeah, i'm already running 12s4p pack i put together. it more than doubles the range and saves 17lbs from stock. That's my problem.. I ran it for too long and coasting downhill for a bit i think the negative drain on the motor did something to the controller. I'm pricing a replacement from them now (can get discount since i'm probably the best advertisement possible here in hawaii, haha). I'd also like to get a kelly so i could mess with the throttle curve and learn more since i'm def a n00b coming into all of this.

End goal is to upgrade this one to 24 with brushless and kelly controller. Then i'll have enough spare parts to order a second frame and wheels to build up one for my GF...

I'm slowly learning about all this at the same time as i juggle the rest of my life (and especially wrenching on my 2t trials bikes).