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[Cortezdtv]

Deans motor cooling pics.  Gotta give it to you man!!! Impressive out the box thinking.



Machined smooth


And I can imagine how you felt when you got this on!!! Accomplished!!!







I don't think you can safely pull the skin of a fx brick, the top connector plug and bms further insulate the batt, I would almost think a cooling plate for them to sit on and maybe on 2 sides might help a little bit the potting material inside the battery will also greatly hinder getting cool anything to the cells



Water cooling plate

The start



I can't find the other pic for the life of me I'll grab a pic when I get home


When I actually go karting, here's the dogs $2500 pillow LOL

[Burton]

Very cool how you essentially made two identical "C water cooling heat syncs" to literally strap on the motor

Dean did you weld this or have someone do that for you?

I bet this thing accelerates hard.

[mrwilsn]

Thanks to zero, Hollywood Electric,Rattlesnake, and forums like this one, many in the karting field are finding out that its possible and cost competitive to build electric karts.  Zero and other manufactures have a great opportunity to significantly increase there sales, component sales can provide a SIGNIFICANT source of needed funds to be used on R&D while also providing the manufacturers with a test bed for no cost R&D. This is a WIN /WIN relationship and the first manufacturers to support this will reap the benefits. Its now possible to simply convert a shifter kart to electric in a few hours, with little electrical engineering experience.  We just need to work out a few problems -COOLING.

2016 could be a good year for karting.  Zero says they will sell their drive train components to consumers in 2016.  I think Burton said a 2014 SR motor cost him $1600 and I would expect the new IPM motor for 2016 might be a little more but should be in the ball park.  The new IPM motor for 2016 will stay a lot cooler in the first place and a liquid cooling solution applied to the stator for added cooling should be much more effective.

[Burton]

Mrwilsn,

This would mean Dean has time to work out the kinks in his water cooling solution before applying it to a IPM should he choose to upgrade.

And given with things like this we often create as a first, whatever he finds as issues he can resolve and make a second unit for the IPM even better ... then sell of his first motor with a premium to another kart racer.

[mrwilsn]

Mrwilsn,

This would mean Dean has time to work out the kinks in his water cooling solution before applying it to a IPM should he choose to upgrade.

And given with things like this we often create as a first, whatever he finds as issues he can resolve and make a second unit for the IPM even better ... then sell of his first motor with a premium to another kart racer.

I'm all for it! I hope Dean keeps us posted on performance improvements [emoji2]

I'm really curious to know what the bottle neck is on top speed with the new IPM motor.  Seems like the motor itself should be capable of higher top speed. Need a bigger controller? Higher voltage pack? Lower coefficient of drag? Better cooling to motor, controller or battery?

Lower coefficient of drag is a gimee. You WILL reach higher top end at the same power if you make it easier to slip through the air (without adding significant weight). The only question is how much.

Bottom line, IPM motor should be capable of doing higher RPM.  So if I want to get to 150mph without sacrificing 0-60 time, what do you have to do to get there? And if you can't get there, what top end can be achieved and what do you have to do to the bike to get there?

Sent from my XT1060 using Tapatalk

[MostlyBonkers]

My guess is that Zero only had the time and resources to bring the IPM motor to market in the same package as the 2015 SR motor. I wouldn't be surprised if the 2017 models bring a new controller that allows higher rpm and more power.

That's pure speculation, based on no info at all! I haven't even checked the specs for the 2016 SR to see if the numbers are any different. I'm also assuming the case is the same and it's just the internals that are fundamentally different.

[BrianTRice@gmail.com]

Regarding specs, I just compared the 2015 SR specs to the 2016 specs for SR and DSR, and noticed that the SR belt went from 132T/30T on the SR to 130T/30T without changing the top speed (granted, it's likely a rounding error or oversight), and top sustained speed went from 85mph to 95mph as already noticed.

All the other changes relate to battery capacity. IPM is literally just used to make the bike more robust at high outputs, at least for now.

[mrwilsn]

Regarding specs, I just compared the 2015 SR specs to the 2016 specs for SR and DSR, and noticed that the SR belt went from 132T/30T on the SR to 130T/30T without changing the top speed (granted, it's likely a rounding error or oversight), and top sustained speed went from 85mph to 95mph as already noticed.

All the other changes relate to battery capacity. IPM is literally just used to make the bike more robust at high outputs, at least for now.

I noticed the same thing when I was combing through the specs right after the announcement. I'm not so sure it's a typo based on what I have been reading about IPM but it would explain a lot.

Assuming its not a typo, I can't figure out how Zero was able to change the gearing on the Zero SR from 2015 to 2016 and yet the 0-60 time and top speed didn't change.  The new IPM motor puts out the same torque, weight stayed the same at 414lbs, and same motor controller.

The reduction in the number of teeth on the rear sprocket from 132T to 130T should result in higher speed but lower torque at the wheel.

Zero could limit the motor to a lower rpm in 2016 to keep the top speed the same.  If they didn't and the gear ratios changed and the motor specs for the new IPM really are the same as the SPM then the 0-60 time for 2016 should have changed (2016 should be slower than 2014/2015) and the top speed should have also changed (2016 should have higher top end than 2014/2015).

However, the torque curves between an IPM and SPM are not the same.  Which is why I am dying to see someone do a drag between a 2014/2015 SR and a 2016 SR to see if the times really are the same and if the top speed really is the same or if that's just what Zero is putting on paper.  After winter, if I decide to trade in for the 2016 SR and no one has done it yet I am going to be on the hunt for someone with a 2014/2015 SR to perform the test myself.  For that matter, I want to see someone do a shoot out between the two....are you listening Troy?    Of course the 2016 should win but I would really like to see someone's impressions after jumping from one bike to the other.....is there a noticeable difference other than the ability to maintain high speed without overheating?

Furthermore, I am dying to see what the new IPM can really do with some hot rodding....like say... liquid cooling....ahem....Dean...or it might even be as simple as some reprogramming of the SEVCON.

[mrwilsn]

My guess is that Zero only had the time and resources to bring the IPM motor to market in the same package as the 2015 SR motor. I wouldn't be surprised if the 2017 models bring a new controller that allows higher rpm and more power.

That's pure speculation, based on no info at all! I haven't even checked the specs for the 2016 SR to see if the numbers are any different. I'm also assuming the case is the same and it's just the internals that are fundamentally different.

Probably right about time and resources but likely because if they wanted to do that and stick with a SEVCON controller they would have to increase pack voltage.  Current Zero's sit at about 116V fully charged.  The Size 6 controller is the biggest controller SEVCON sells that operates at that voltage.  To stick with the SEVCON Gen4 line they would have to go to a 150V (fully charged) pack (125V nominal).  See the image below from the SEVCON spec sheet.  Also note that the SEVCON controllers at the higher voltage have an asterisk saying they are not yet available.

Based on what I have read it sounds like Zero is pretty committed to the lower voltage packs but things can always change.  Maybe the shift to the IPM was to lay the ground work for a move to a higher voltage pack and bigger controller.   

I have been wondering about the case of the motor too....I'm pretty sure Zero website is using the same close up picture for the 2016 as they are using for the 2015 so will have to wait until seeing the real thing to know for sure.

[MostlyBonkers]

Thanks mrwilsn. What I find particularly interesting about those specs is the maximum sustained current for 60 minutes. The size 6 only manages 220A. That's a little less than half the current required to provide the 50kW of power that the SR motor is rated at.

I appreciate that 220 continuous is still 32 hp and more than enough to sustain 70mph. In fact it's probably about twice as much power that's needed. At that rate the battery would be empty in less than half an hour on all but the 2016. It does highlight just how deceiving all these headline figures can be, yet we still grasp onto them.

My VFR produces up to 170hp at the crankshaft. That's likely to be 130-40 by the time it's been transmitted through the gearbox and drive shaft. That at max revs with the throttle wide open. It never gets used like that. The reality is that I'm probably only using about 50hp most of the time - if that!

I'm labouring the point... All of this does help understand how an engineer might design to the limits of one component, thinking that less heat will have to be dealt with than is found later in testing.

I have no idea how flexible the sevcon controllers are in the way they can be programmed. Obviously reasonably flexible, otherwise an IPM motor just wouldn't run. I suspect that they were designed for SPM motors though. I'd bet on an entirely new controller being required to get the most out of an IPM motor. I reckon this is a short term fix to deal with the heat, but in the same packaging. There's a great opportunity here for a brand new IPM motor, built from scratch to optimize the IPM technology. Higher revs, wider and flatter torque band, more power sustained for longer. A new controller of course.

Back in the real world, where Zero don't have millions to spend on R&D, I think that what's on offer is great! [emoji4]

[ctrlburn]

Question on the Waterjacketed Cooling.
If the liquid had magnetic/ferrous properties - would the system be self-circulating?

[NEW2elec]

Wow advanced question.  I'm interested in the answer to it but I think if you can get the fluid levels right heat convection should circulate pretty well on its on.  Your way might create cold fusion and would just be too embarrassing to discover it when you were just trying to cool a Kart motor

[protomech]

Assuming its not a typo, I can't figure out how Zero was able to change the gearing on the Zero SR from 2015 to 2016 and yet the 0-60 time and top speed didn't change.  The new IPM motor puts out the same torque, weight stayed the same at 414lbs, and same motor controller.

The reduction in the number of teeth on the rear sprocket from 132T to 130T should result in higher speed but lower torque at the wheel.

Zero could limit the motor to a lower rpm in 2016 to keep the top speed the same.  If they didn't and the gear ratios changed and the motor specs for the new IPM really are the same as the SPM then the 0-60 time for 2016 should have changed (2016 should be slower than 2014/2015) and the top speed should have also changed (2016 should have higher top end than 2014/2015).

We're talking about a 1.5% difference in gearing. That's not going to make a noticeable change to either the acceleration (3.3s 0-60 to 3.35?) or the top speed, assuming RPM limited .. Zero probably just copied the values from last year.

The sustained top speed is the big change, and hopefully the IPM motors alleviate the majority of the overheating concerns some people had with the SPM motors.

Probably right about time and resources but likely because if they wanted to do that and stick with a SEVCON controller they would have to increase pack voltage.  Current Zero's sit at about 116V fully charged.  The Size 6 controller is the biggest controller SEVCON sells that operates at that voltage.  To stick with the SEVCON Gen4 line they would have to go to a 150V (fully charged) pack (125V nominal).  See the image below from the SEVCON spec sheet.  Also note that the SEVCON controllers at the higher voltage have an asterisk saying they are not yet available.

Switching to the 150V Sevcon Gen4 G120 - assuming that line is shipping - wouldn't bring significant benefit. The max and continuous powers are slightly higher if at all for G120 over G80 (2 min rating: G120 is 29% higher voltage, G80 is 22% higher amps), and Zero would have to either use a smaller cell or use much larger bricks to build their bikes.

Sevcon has a high-voltage Gen5 motor controller sampling now, in production for early 2016. Comparing the 400V Gen5 Size 9 to the 400V Gen4 Size 8, the Gen5 is slightly more compact (26% less volume), lighter (6.8 kg instead of 10 kg), and higher power (50% higher peak current, 33% higher 2 minute current).

The larger controllers are liquid-cooled, but if similar improvements make their way down to the low voltage controllers, whenever they ship, then Zero should be able to pump even more power into the IPM motor. Single-brick FX can output 20 kW, so a 3 brick 50 kW S and 4 brick 70 kW SR seem reasonable.

[trikester]

Back to the spray bottle. 

Back in 2013 I was riding my Zero powered e-trike in the Inyo Mountains in mid-summer and I had problems with motor overheating on the steep switchback sections of trails. I started carrying one of those squirt bottles to spray the motor after stopping to let it cool. The water spray made a big difference in how long it took to get going again.

Trikester

[MostlyBonkers]

There you go! I knew it was a good idea!!! Thanks Trikester. [emoji4]