Air Cooling my x5

[adrian_sm]

what's the name of that conical tool used to drill the holes? Thanks.

Do you mean a step drill? Here is a link to the one I used.

[The Mighty Volt]

what's the name of that conical tool used to drill the holes? Thanks.

Do you mean a step drill? Here is a link to the one I used.

That's the one. Thanks Adrian!

[John in CR]

I don't see how a step drill is useful for shaping these holes. To maximize air flow through any hole you want a smooth and rounded radius transition to minimize turbulence. Also, for the perimeter holes I've made in 3 sets of covers there wasn't clearance for a step drill, because they butted up against and into the bolt flange to position the hole as close to the perimeter of the interior air space as possible. Those aluminum covers are so soft that it's really easy to do with a hand drill, and the same bit works well to taper the holes by taking your time and an angled circular movement with the drill. The only challenge I found is to get uniform placement of the perimeter holes, because my preference is to make lots of small holes to reduce the size of debris that could enter. eg On my most recent set the holes are quite angled and small enough diameter compared to the material thickness that when viewed directly from the side the hole is only a small slit to the interior, so a rock much smaller than the hole will just hit metal and bounce off unless it flies at the motor at just the right angle. Add that the holes are moving and the rock has to have perfect aim, perfect angle, and is coming at the perfect speed.

John

[The Mighty Volt]

That's what DB uses, he holds up a small conical bit in the video and says he hopes that whoever invented this bit deserves a lot of money!!!

The thing of the step bit is that it allows you to start the hole smack-dab where you want the hole to "finish" so to speak.

[icecube57]

Would scoops like this help force air into the hub.

[John in CR]

Would scoops like this help force air into the hub.

No. Jeremy did a calculation in the other thread. Forced air like Arlo1 did with fans on the stator spokes to suck air in from the outside on one side, or a centrifugal fan approach are really the only options. That is unless you have a drum brake on one side whose stationary cover could be used to mount a powerful ducted fan to blast air into the motor, but I'm the only one around here using motors where that is viable. The last option is modding the one side cover to take a bearing with a much larger ID, and using the extra area between the axle and the bearing to force more air through. Someone did that with good success though I've lost the link to that video.

The moral of the story is trading an X5 for a 9C was a big step down in power. Sure your 5303 was hard to drive, but no way a 12fet was going to do it, and 18fets cuts it thin on the hard to drive motors. What you needed was the big 24fet like I'm using to drive my even harder to drive hubbies without issue.

You're a big guy like me, and we need manly motors or higher speed motors with a gear reduction to make them manly. Do you want me to tell you how I plan to dependably run my lowly 9C at 4kw continuous and 7-9kw peaks?

[icecube57]

The 9C is a step down from the x5. I dont regret it at all. That was a big weight hit. I had the GM before which was a 9x5 and that thing was hard to cool but I finally got it to take 4k continuous. This being a more appropriate winding should run cooler than the GM. Im chasing after that same type of build i had previously with the Gm. I expect some performance but not stellar. With the 9C Im looking for 88v 65A possibly more consevative than that. I got the GM to do a hard 15 miles without overheating after the bugs were worked out but that was high speed 40mph riding. It did have the same holle pattern as I have in my 9C now. I honestly dont have the on the road playground that many of you have. I dont do technical riding like methods did with his bike recently. I dont tackle alot of steep grades unless i have a good running start.I have to survey areas and plan rides that I think the bike can handle. The topography of Georgia sucks to where its a challenge to go anywhere on my bike with out being under full power and wasting whs. I can run to the store and get small bit of groceries and stuff but thats still a challenge with the terrain, topagraphy and nature of the drivers around here makes a street rod less appealing and my life more valuable. The build is shifting to be recreational riding with the ability to hold my own when i need to. I do feel i could hange with GinDC if i ever had to tag along on one of his rides. But I can do that type of riding here not even in a wet dream. Id like to take my bike to several areas and explore the city or town. The weight of the X5 is an advantage but its very unappealing when transporting my bike. But please do tell me your secrets.

[icecube57]

Just an idead a friend and are are fooling around with.

[El_Steak]

i took a different approach to cooling for next season. I lost 20 pounds since november and i will probably be under 150 before next season starts.

this should help reduce heat generation while climbing and accelerating. It will also increase my range, improve performance and reduce tire wear

my girlfriend thinks i am loosing weight to improve my health and looks, but its all about the ebike baby !

[John in CR]

Good job El Steak. Nothing beats increasing that power to weight ratio. Congrats on the hard work. Hopefully I'm not far behind, but I'll never see 150, but low 190's sure would be nice.

[El_Steak]

thx, I'm just 5'7" hence the 150 pound.

It wasn't too hard actually, I'm just counting my calories using a little ipod application.

[oldpiper]

thx, I'm just 5'7" hence the 150 pound.

It wasn't too hard actually, I'm just counting my calories using a little ipod application.

That's why I find it so hard to lose weight,I don't have an iPod! Thanks, El Steak!

Cameron

[John in CR]

thx, I'm just 5'7" hence the 150 pound.

It wasn't too hard actually, I'm just counting my calories using a little ipod application.

That's why I find it so hard to lose weight,I don't have an iPod! Thanks, El Steak!

Cameron

I'll pounce on that excuse too, though I know the real excuse is too much time at the keyboard much of which was taken away from activities involving physical movement without adjusting caloric intake. If anything I take in less calories than 15 years ago.

Computers and video games are the primary cause of greatly increased obesity, yet McDonalds and Whoopie pies get the blame. This misguidance has given Big O, the 1st Lady and others the idea that they somehow have the right to tell you what you can and can't eat, and they actually believe it's their responsibility to do so.

[docnjoj]

Hey John
I don't care to debate the Healthcare politics but I do know that Obesity and Diabetes are the two fastest growing killers in America. Maybe the Gov't shouldnt get involved, but you and I ( I'm 6'2'' and 230 lbs) have weight problems. It is considered an epidemic by CDC. Our bikes may be the only thing that save us from sure death or disability. Sorry to get into this but I teach Health Care Administration for a major university and have to rehash this sh*t every quarter.
Warm personal regards
otherDoc

[Hyena]

I reckon a big blower mounted to the chain stay and pointed at the largish holes would be just as effective at cooling and easier to implement than playing with fins and internal fans. When I get time to actual make and test something is another issue...

Our bikes may be the only thing that save us from sure death or disability.

Good for you guys, my bike will CAUSE me sure death or disability

[El_Steak]

Good for you guys, my bike will CAUSE me sure death or disability

I Second that

[LarsE]

Hi

Some cooling modifications to my rear hub motor that I am working on..


Uploaded with ImageShack.us]
The cooling is 48 of http://www.dealextreme.com/p/aluminum-cooler-heat-sink-chipset-for-ram-memory-square-type-8-piece-set-35817
They are grinded to the radius of the hubmotor 16cm with a homemade tool that fits a cordless drill and then glued on with arctic alumina.
My side panels is of course vented with big holes to let ear inn and out.
Its been a lot of work, (the grinding) so I am hoping it will take some kW without overheating.

[Doctorbass]

Hi

Some cooling modifications to my rear hub motor that I am working on..


Uploaded with ImageShack.us]
The cooling is 48 of http://www.dealextreme.com/p/aluminum-cooler-heat-sink-chipset-for-ram-memory-square-type-8-piece-set-35817
They are grinded to the radius of the hubmotor 16cm with a homemade tool that fits a cordless drill and then glued on with arctic alumina.
My side panels is of course vented with big holes to let ear inn and out.
Its been a lot of work, (the grinding) so I am hoping it will take some kW without overheating.

The problem is not to add surface dissipation INSIDE the motor.. but it's more evacuating the heat from the inside to the OUTSIDE of it

Doc

[John in CR]

The heat sinks sure can't hurt. The real key is the strategy you use to create an actual flow of air bringing fresh air into the motor. I'd hate to see all that heat sink work go to waste with ventilation holes that do little to flow some air like are typically done around here. You can always add fans like Arlo1 did with some sucking air from one side to the other that makes one side the intake and the other exhaust, along with fans blowing on the stator too for extra turbulent flow at the stator.

[Arlo1]

Hi

Some cooling modifications to my rear hub motor that I am working on..


Uploaded with ImageShack.us]
The cooling is 48 of http://www.dealextreme.com/p/aluminum-cooler-heat-sink-chipset-for-ram-memory-square-type-8-piece-set-35817
They are grinded to the radius of the hubmotor 16cm with a homemade tool that fits a cordless drill and then glued on with arctic alumina.
My side panels is of course vented with big holes to let ear inn and out.
Its been a lot of work, (the grinding) so I am hoping it will take some kW without overheating.

Yup get some active air flow from the out side into the motor and onto those sweet heat syncs and you are ready to push that motor to over 30x its rating like me lol.

P.S. The pic of the peak in my SIg is real and its acurate and on my x5 thats fan cooled

[LarsE]

Hi.
The heat sink needs vented side panels, and they are. How effective the heat sink will be is unknown, only time will tell. The side panels are maybe not the most extreme open design but close (afraid it will collapse if I overdo it.
Next up is gluing the heat sink to the other side of the stator (only 24 heat sink in picture) and treading the phase wires.
I have been looking for some fans too run inside of the motor but I have not yet found something with the ability to take the heat and vibration so the fan cooling is canceled for now. Maybe I will look more into it next winter
This year I am happy with heat sink + vented side panels + fatter phase wires.

P.S. Arlo1: almost unbelievable level of current with a hub motor, with those Amp's I expect you are taking phase wires under the bearing or more likely your hub motor got zapped with lighting in a storm or something.

Lars E

[El_Steak]

Major fail for me this morning...

Hit a nasty bump and one of my cute little aluminum fan blade broke off inside the motor at around 60km/h.



Predictable carnage occured inside the motor. After I managed to slow down safely, my rear wheel locked completely. Had to get someone to pick me and the bike up in a minivan. Humbling experience...

Those "blades" where just epoxied with JB-Weld to the side of the "ribs" inside the cover.

I particularly appreciate the fact that I had predicted this would happen and even built a metal disk to epoxy on the other side of the blades to secure them in place. But I procrastinated and never got around to installing said disk...

Tomorrow when the epoxy has set, I will glue this metal disk over the blades. It will serve 2 purposes:

1- Secure all the blades together and prevent a single blade from coming loose and trashing the windings
2- "Channel" the fresh air directly to the windings instead of the stator.

I'll post pics of the thrashed inside when I get back home tonight.

Now I need to get a new 2807 quickly to get back on the road, hopefully I can just do a stator swap and not have to rebuild the nice 24inch wheel that Holmes did for me.

[John in CR]

Ouch! Sorry to hear about that. That possibility made me nervous enough to use bolts and epoxy in mine with blades. Good thing too, because my son is really hammering the motor....1 bolt on each blade to secure it, and epoxy to both hold it in place and secure the nut.

[Doctorbass]

So you can say that this blades principle also offer amazing braking force advantage?

Sorry to hear you broke your motor

I know how frustrating it can be wneh you need the help of unknown person to cary you and your ebike to your home... not a good publicity for ebikes...

Doc

[El_Steak]

So you can say that this blades principle also offer amazing braking force advantage?

¸



I was lucky it didn't lock up at 60km/h, don't know If I would have been able to remain on the bike...

Do you guys know if I can insert the stator of a new-style 9c motor with ISO disk mounts covers inside the magnet ring of the old-style 9c motor?

This bike is my main mode of transportation to work so I want to get back on the road as quickly as possible and if I can avoid rebuilding my 24inch wheel, all the better...

Until then, I'm stock back in traffic with the rest of the cage drivers