QS 138 70H with Gearbox

[john61ct]

Any links to a CAN-BUS battery?

[msf1t]

Recent arrival

PXL_20210930_173728006.jpg (394 KiB) Viewed 1535 times

Going in this KX

PXL_20210930_173952789.jpg (498.33 KiB) Viewed 1535 times

[juman]

Very nice man, doing very similar with a CRF frame. Just finished cleaning/rebuilding stuff, did pinch my rear tube so ehhh but now basically just fitting the new motor/controller in and hopefully I measured right for the battery but eh, figure it out as I go.

10022021-ERF.jpg (49.97 KiB) Viewed 1482 times

[cheapcookie]

Very nice man, doing very similar with a CRF frame. Just finished cleaning/rebuilding stuff, did pinch my rear tube so ehhh but now basically just fitting the new motor/controller in and hopefully I measured right for the battery but eh, figure it out as I go.
10022021-ERF.jpg

What model Honda?

[juman]

What model Honda?

That is a 2003 CRF450. Really with MX frames from 125cc-450cc are quite similar save for engine mounts. Still got a ton of work ahead of me figuring out mounting things and battery though. Easy part that I'm familiar with (rebuilding bike parts) is done, now it's the more complex engineering aspect.

[DanGT86]

Nice bike. I have a 98 CR125 frame in the garage that looks exactly like that. Do you know what frame changes there were over the years? Looks like almost none.

[juman]

Nice bike. I have a 98 CR125 frame in the garage that looks exactly like that. Do you know what frame changes there were over the years? Looks like almost none.

What I see with most dirt bikes are the 125-450cc frames are nearly identical save for the engine mounting tabs. I know it was sometime in the late 90's that Honda started using the 'open' frame in the center rather than the center bar. I have a Husqvarna bike as well and it's frame would not be as easy to do this on, has a middle bar where the gas tank sits currently. I wanted to use a Husky frame because newer parts but eh the electric conversion looked much harder.

[Farnhamstj]

New guy, Following up on this thread to see if there has been progress with this motor. Or links to other articles related to this qs138. I'm considering placing one in a 1981 Honda xr80. Width of motor at 233.8mm is pretty wide. I've got a Segway x260 and am planning to modify the frame to accept Surron sized battery.

[Maico4]

I installed this motor with Votol EM150/2 controller (210A) onto a 1991 KX100. Easy install and the bike rips.
Next one is going onto a 2008 YZ250F with a Votol EM260 controller (350A) same motor.

You can buy this combo with wiring harness, throttle, and super programming from ElectroandCompany.com . Austin there, has these combos dialed in. He can do it with either controller EM150/2 or EM260.

If you need a 520 sprocket, Mighte.com carries them. 30 euros.

On the KX100 I had to cut off the top motor mount also, it took up valuable battery space. I put a KLX110L 2020 shrouds on it also since the old KX only had a shroud on one side.

[Paulflieg]

Hi,
Found a 520 sprocket? Where? I am very interested !!
Mighte.com?? Not found....

[Jordan325ic]

https://mighte.me/product/13t-520pitch- ... -sprocket/

It’s mighte.me.

I also have one more 12T 520 sprocket, $30 shipped

[Paulflieg]

Thanks!
that 13t would cost me $ 70 .. Expensive! I go the opposite way. Found a stealth sprocket, 428-54t ... and it was only $ 40

[KiefRichards]

Has anyone mounted the 138v3 with the drain plug not on the bottom?
The only way I can get a decent chainline is to rotate it about 40 degrees from level.
Im worried it may cause issues with the gearbox lubrication system. Just curious if anyone else here has done this.
Thanks

[speedmd]

Most of the newer gassers have moved the drive sprockets lower than the swing arm pivot. Raises the rear end a bit when power is on which helps in the woops and also lowers the mass a bit. Need to add a good top chain guide and most likely a good bottom one also.

[Gifting]

I have read every post in this thread and learned a lot so thank you for that! I am very close to pushing the buy button for this motor and the EM200 controller. The plan is to mount this to a Yamaha YZ85 frame. But I´m stuck at what battery to buy for this build so if anyone could point me in the right direction that would be great! I would prefere to buy a premade pack but I´m also open to buildning my own. What kind of specifications for the battery are we talking about for this motor to run at it´s best? I have been looking at Lipo batteries and if i lived in the US I would probably buy one of the Lipo packs from Electro & CO but I don´t so that´s not an option. But Lipo, Liion or something else doesn´t really matter to me as long as the match with the motor is good.

[Jordan325ic]

I have read every post in this thread and learned a lot so thank you for that! I am very close to pushing the buy button for this motor and the EM200 controller. The plan is to mount this to a Yamaha YZ85 frame. But I´m stuck at what battery to buy for this build so if anyone could point me in the right direction that would be great! I would prefere to buy a premade pack but I´m also open to buildning my own. What kind of specifications for the battery are we talking about for this motor to run at it´s best? I have been looking at Lipo batteries and if i lived in the US I would probably buy one of the Lipo packs from Electro & CO but I don´t so that´s not an option. But Lipo, Liion or something else doesn´t really matter to me as long as the match with the motor is good.

Where space is tight people normally go li-ion. You want a battery between 48-72v (this is the spec for ab em200 controller), which has enough capacity (ah or amp hours) to provide the power (kw-kilowatts) you’re looking for. So for example a 72v, 25AH battery that can has a ‘50A continuous / 100A peak’ BMS gets you 7.2kw (72v x 100a) peak power or ~10hp. In simple terms that’s what you’re looking for: 1. voltage, 2. capacity and 3. discharge rate. Then 4. ‘does it fit?’ and 5. ‘will it burn my house down?’.

An Off-the-shelf battery likely will not use the space too effectively, and you will have to get creative with mounting. Small motorcycle frames are often difficult to fit enough battery. I’ve used unit pack power batteries in China before for a custom sized battery, but it will not be in a case.

[KiefRichards]

Anyone using the 138 find the eyelet lugs on the phase wires too large? Ive got an em150 controller and the posts are only about 2mm larger than the holes in the lugs. Ive attached some pics.
Im considering swapping the lugs for ones with smaller holes. Just wondering what others have done, or if its a non-issue I shouldn’t worry about? Opinions?

[owhite]

Youre fine. Stick a washer between the lug and the bolt that pins it to the terminal. That will maximize contact electrical contact with the bolt and the oversized lug, and save you the trouble of soldering on a new lug.

[KiefRichards]

Thanks

[Gifting]

Where space is tight people normally go li-ion. You want a battery between 48-72v (this is the spec for ab em200 controller), which has enough capacity (ah or amp hours) to provide the power (kw-kilowatts) you’re looking for. So for example a 72v, 25AH battery that can has a ‘50A continuous / 100A peak’ BMS gets you 7.2kw (72v x 100a) peak power or ~10hp. In simple terms that’s what you’re looking for: 1. voltage, 2. capacity and 3. discharge rate. Then 4. ‘does it fit?’ and 5. ‘will it burn my house down?’.

An Off-the-shelf battery likely will not use the space too effectively, and you will have to get creative with mounting. Small motorcycle frames are often difficult to fit enough battery. I’ve used unit pack power batteries in China before for a custom sized battery, but it will not be in a case.

Thank´s a lot for your reply. I will continue my hunt for the best battery!

[speedy1984]

My method is turning down the stock sprocket and drilling out the two bolt threads.Then i will bolt the stock unit to the
mohttps://mighte.me/product/13t-520pitch-qs-v3-and-70h-sprocket/unting sprocket and throwing 4 small tig welds on the stock sprocket onto the shaft once the sprocket is turned in the motor direction taking out any wiggle room first.This way if and when i need to change the new 520 sprocket i dont have to weld and turn down more sprockets,i just grind off the 4 tig welds and undo the two bolts and change.Not a perfect solution but on a cheap motor like this there is not much we can do without it getting costly.