Suzuki RMZ 250 EV Restomod

[Eastwood]

Looks like I will have this 72v battery and controller for about 2 months as 3Shul said at least 4-6 weeks for the controller. That will give me time to build the battery but waiting on the Molicel cells to come back in stock.

That being said I made my "temporary set up" more secure and safe as before the battery’s were just sitting on top of the motor lol

Made this bracket and bottom plate for the battery. Much more secure now, and will be able to hit some enduro trails now. Again this is just a temporary solution.






Should have wrapped the wood plate and cushions with gorilla tape to waterproof, guess I will do that tomorrow.



Also covered the batteries in some abs plastic to add some protection if I drop the bike. The plastic is not that thick but it’s better than nothing. Had all these materials laying around so put it to use.

 

[gobi]

Looks like a factory bike, woa, you did good bro,

 

[Eastwood]

Looks like a factory bike, woa, you did good bro,

Thank you! That’s sort of what I was going for a factory look, but also was trying to create a brand new motorcycle, well a completely restored bike. I still have to put the graphics on the bike. I’m waiting on the graphic designer to send me a proof.

Also need to do some suspension tuning as I have the front forks with the compression all the way on the softest setting, so I need to tweak the shim stack. The rear shock needs some tweaking as well, but I haven’t messed with the adjustments yet on that. Definitely need to slow down the rebound feel like it’s pogo sticking me up off the bike. So yeah, not done yet with the bike but getting close.

Oh yeah, I still need to weigh the bike. I’ll try to put it on the scale soon, but my right shoulder is a little jacked up at the moment, don’t ask me how that happen
But yeah, obviously the bike is going to get heavier with that 330 cell battery, maybe another 25 pounds-ish.


Here’s a short clip from yesterday, was testing the suspension. The high speed compression feels really nice but the low speed compression is slightly harsh but not bad.

 

[Eastwood]

So battery plans and thoughts..,
Waiting for the cells to come back in stock to order. Still contemplating how many parallel groups.

So 30s/108vnominal @250amps = 27kw…
I’m planning to run that for trail and enduro.
Molicel p24a is 45amp discharge continuous.
At 27kw that’s only 22.7amps per cell group at 11 parallel. 12 parallel would be 20.8amps per cell group. 13 parallel would be 19.2amps per cell group. That’s half the max continuous even at 11p Although some people say the max continuous amps are 30-ish.

This pack should be really efficient. Planing to use 1mm copper busbars with 0000 AWG battery wires. It’s overkill but will help with efficiency. The controller 3Shul (CL1000) can discharge 500a continuous but only using about half of that, this will also help with efficiency. Although I do plan to use more than 250a at times but not continuous for long periods. The highest DC amp I would use is 450amps. So 450a x 108v = 48.600kw… that might be too much for the QS 138, obviously NOT using continuous, but maybe it could handle it for a short drag race. Then fully charged at 126v x 450a = 56,700kw
It will be interesting to see what I can push the small QS138 at for drag racing purposes, just against gas bikes not official drag racing at a strip. Like I mention 250a would probably be my continuous amps for my main map/settings for Trail and enduro.


really considering 12p or 13p 360/390 cells but harder to fit and heavier, trying to find a good balance. Need lots of range but weight is important as well. Although range is the most important over weight.

Battery power and weights.,
30s 11p = 47.84lbs = 4.99kw
30s 12p = 52.38lbs = 5.44kw
30s 13p = 56.7lbs = 5.89kw
Plus the added weight from 0000awg wires, busbars, BMS, etc.

So if I end up going with 13p-390 cells, would just order 400cells to have an extra 10cells in case some of the cells are not evenly matched with capacity, internal resistance, etc. I really like the 13p option because it’s close to 6 kWH battery.

Please feel free to chime in on battery thoughts!!
Here’s a pic of the bus bars I’ll be using.

 

[j bjork]

I think if I would have just one battery I would want at least 6kwh. Each of my batteries is 4kwh, but I can only use maybe 3,5 as I cant charge full with my present controller. I think that gives a good range on most tracks, and I suppose one 6kwh battery would give similar range. It is only fast, soft tracks where the range can be a little short. On most 7-9km tracks I can do 3-4 laps on each battery, so 6-8 on both batteries. But there is one maybe 12km long, fast sand track where I can only do 2 laps on each battery. On that track I would have wanted a lap or 2 more.

 

[Eastwood]

I think if I would have just one battery I would want at least 6kwh.

Yeah that’s what i’m leaning toward, 6kWh-ish. Seems like great capacity for dirtbikes.

If I did 30s 14p 420cells, that would be 6.3kwh at 61lbs.. But with 14p the cost is getting up there

 

[harrisonpatm]

Please feel free to chime in on battery thoughts!!
Here’s a pic of the bus bars I’ll be using.

Looking forward to hearing your reviews on those, I've spied them and similar on aliexpress and they seem like a good option for those with weak-ish spot welders, too weak to do the copper-nickel sandwiches, but still want the high current abilities of copper connections.

 

[rivvs]

Yeah that’s what i’m leaning toward, 6kWh-ish. Seems like great capacity for dirtbikes.

If I did 30s 14p 420cells, that would be 6.3kwh at 61lbs.. But with 14p the cost is getting up there

390 p42a will be a hard fit in a rmz frame. My pack is 364 cells in the Honda and there is not any space left. I was able to fit 400 p26a wich is 18650 format in my rmz and I had to grind part of the frame.

 

[Eastwood]

Looking forward to hearing your reviews on those

Yeah for sure, will leave feedback on these busbars.

they seem like a good option for those with weak-ish spot welders, too weak to do the copper-nickel sandwiches, but still want the high current abilities of copper connections.

Spot welding part is 0.15mm copper nickel composite material. Says the seller..

Yeah was going to do the copper-nickel sandwich, but chose these busbars to have better efficiency with the thickness of 1 mm copper. Definitely would be a challenge to spot weld 1.0 mm copper without heating the cells too much. These style busbars look like our best option for higher output packs.

 

[Eastwood]

390 p42a will be a hard fit in a rmz frame. My pack is 364 cells in the Honda and there is not any space left. I was able to fit 400 p26a wich is 18650 format in my rmz and I had to grind part of the frame.

Yeah, 390 cells would be an extremely tight fit, if even possible. The current configuration I have fitted with the cell holders is 330cells-11p but I can fit at least one more group 360-12p.

Probably will cut off that top motor mount on the 138 to fit more cells. But yeah, I don’t plan on cutting the frame anywhere except the main motor mount which I already removed from the frame.

 

[Eastwood]

I think the more challenging part is figuring out how I will connect the two cell walls with using these style bus bars. I guess the seller could extend tabs off the ends of the bars and could manually bolt them together. Definitely not going to be able to spot weld 1 mm copper ends together. Another option is, design the busbars to fold the two walls together like a hinge. I don’t know yet, just brainstorming, Ideas??

 

[Eastwood]

Finally ordered the cells! The cells have been on backorder for couple of weeks. Can’t believe I spent that much just on the battery cells …

Ordered 370 but will use 360cells, still working on the configuration of the cells before ordering the custom 1mm copper busbars.

Molicel p42a 4200mAh, 45amp max discharge
30s 12p = 50.40 Amp hours = 5.44kwh

The 3shul CL1000 controller is still on order, they said around may, 28th which is quicker than I was expecting. I’m definitely going to have to modify the rear plastics to fit this controller, so that’ll be interesting. If I would’ve went with the far driver, it would’ve fit perfectly inside the airbox, but the feedback on the far drivers for the throttle control, really steered me away from that product. It seems like the 3Shul is the the best controller out for these types of builds.

Battery source, they still have the cells in stock, If anyone is needing, they tend to go out of stock really quickly these days.

Molicel 21700 P42A 4200mAh 45A Battery

Discover the best all-around cell in the 21700 form factor size. With a capacity of 4200mAh and a 45A maximum continuous discharge rating, the Molicel 21700 P42A battery delivers exceptional power and performance. Unlock your device's true potential with this high-quality battery.

www.18650batterystore.com

WELLGO busbar contact, Ken Bao,
Ken has great communication! Like to give credit when credit is due.
Huizhou Wlj Technology Co., Ltd.
Huizhou Wlj Technology Co., Ltd. - Battery Copper Busbar, Battery Bracket

 

[Eastwood]

Rreceived the battery cells, 370
57.2lbs!

 

[SlowCo]

Lots of battery building work ahead.
Good luck and be careful!

 

[Eastwood]

Well changed the battery design again
28s 11p - 308cells - 4.657KWH
Trying to keep the weight down for this build.
I’ve tried many different battery shapes and configurations with the cell holders even up to 420 cells but just to heavy.

The current configuration is much wider than the original design. All the weight will be toward the bottom of the bike. Also with this design, I’ll be able to pull the battery out the side of the bike without having to remove the seat and gas tank. Have lots of room for the BMS and contactors above the battery. I may be able to put the 3shul controller above the battery as well, maybe ..

Got just enough room to build a battery box. The plan as of now is to use thick ABS plastic with some aluminum shields on the outside of the box around the high impact areas. Will use some rubber sheets on the inside of the battery box and between each ply/level.



May have to trim down some fins on the qs138 to allow for clearance with the battery box, hopefully not.

 

[Eastwood]

Did my first ride today on some hard enduro trails
Very impressed with the QS138. The motor did really well with hill climbs etc…
I’m still using the temporary battery and controller.
The bike got her first beauty marks today! Lol
Had to drop the bike on this rocky section at slow speed. It was one of those situations where you can’t put your foot down so you have to ditch the bike to save your body lol
Thankfully, I didn’t hit the ground was able to stay on my feet



This is my friends bike KTM 300

The beauty Mark photos below!
Scratched the side of the motor, brake reservoir and hand guard. No big deal I expect this to happen while riding gnarly Enduro trails


The bike got a little muddy today, not to bad.


Was running 10kW today. Can only imagine once I get the battery build finished and the 3Shul CL1000 controller installed! For trail use I can’t see needing more than 20kW maybe 15kw might be the sweet spot for slow technical trails.

Lastly, here’s a picture of the final shape of the battery. Waiting on the wellgo busbars and also will have the 3Shul controller next week

 

[Eastwood]

Received some goodies today


Surprised how heavy the 1.0mm copper busbars are. Its good thing though

 

[TorgueRPM]

Did they mess up the polarity on the CL1000 battery terminals?

 

[Eastwood]

Did they mess up the polarity on the CL1000 battery terminals?

Looks like they had it labeled backwards and they manually corrected it

Edit: just checked it with a multimeter, The way they manually corrected is the correct polarity. I’m guessing because of all the back orders they didn’t have time to 3-D print new covers with the correct polarity.

 

[TorgueRPM]

How do you check the polarity? Now I'm worried they might have missed it on mine

 

[Eastwood]

How do you check the polarity? Now I'm worried they might have missed it on mine

Just by placing the negative to the B- and positive to the B+. My controller had .2V so I could see the polarity was right.

 

[Eastwood]

She got a little muddy today. Did 24 miles of enduro through the very wet mountains.

Need to soften the front forks! Found the bike deflecting off of rocks pretty bad. Although I expected this, considering this bike suspension is set up for motocross being an Rmz (stock suspension). I will have to revalve and respring. I don’t wanna make too much of a commitment yet because I don’t have the full weight of the bike with the final battery and controller. So I’ll just start with the pressure springs in the twin chamber Showa forks. If that’s not enough, I’ll revalve by either removing some shims, or getting thinner shims. Although the bike is not at its final weight yet, it still needs to be softened as it’s way too harsh for trail/enduro style riding.

Besides that the bike did excellent today!
The rear shock almost feels dialed it needs some slight tweaking. Unlike the front forks, were the compression is turned all the way soft and it’s still way too hard lol

The motor stayed cool the entire day, even with steep hill climbs at slow speeds. Really happy with this QS 138.

One other change, I need to get the seat height lower, probably will shave down the seat foam. Even at 6 foot tall it’s difficult for me to put my feet on the ground through some of this technical terrain.
The only other way to lower the rear is by modifying the rear shock or getting an adjustable dog bone, which I don’t like either of those options, because it affects the travel of the shock.

 

[Eastwood]

Took out the cartridges from the forks, looks like the shim stack is not stock. I believe these twin chamber Showa Forks come with a single stage shim stack, but there is a two stage shim stack. Which is a good thing, it gives me a starting point as I had planned to do a two-stage, shim stack.

I’ve ordered new pressure springs for the cartridges. The stock ones are 1.9kg/mm and ordered 1.0kg/mm from race tech. Should be much better for Enduro.

I will leave the shim stack alone for now, and we’ll put the new pressure springs in and do some testing. I don’t want to do more than one change at a time so I can get a better feel of what’s happening with the forks.

Will also have to change the main springs in the fork, but one step at a time. The main springs feel a little stiff, but they’re not too bad.


Lastly, removing the cartridges are extremely easy for these twin chambers as you can leave the forks on the bike. Makes tuning very accessible

 

[Eastwood]

Got the new cartridge pressure springs installed
The Forks feel much softer on the initial movement/hit. Just did some testing in my back yard, but will test off-road soon to see if the front wheel is still deflecting off rocks, roots etc.

If I had to guess, probably will still soften the low speed compression on the shim stack. There’s no way of really knowing until I do some hard Enduro riding.

Also will still change the main springs in the fork, from my understanding, it’s always best to get the spring rate right first and then start tweaking the shim stack.

 

[speedy1984]

I'd just build the bike as you intended then play with suspension.You have moved weight around in the chassis that it wasn't intended for so things change as I'm sure you know