Luke's new race bike build thread.

[Whiplash]

What kind of max speeds were you guys seeing? It seems like these motor failures must be from the single speed setups you all run. Every time you come out of a corner and lug the motor up to speed you are generating heat that will eventually heat soak and then kill the motor. I would think some gearing is in order or liquid cooling to handle the speed changes..

 

[liveforphysics]

What kind of max speeds were you guys seeing? It seems like these motor failures must be from the single speed setups you all run. Every time you come out of a corner and lug the motor up to speed you are generating heat that will eventually heat soak and then kill the motor. I would think some gearing is in order or liquid cooling to handle the speed changes..

Motor speeds weren't the problem at all for our bike. After around 15mph, our motors efficiency stays between 84-92% for the whole RPM range we were using.

Our motor also didn't die from overheating, it died from mechanical brush failure caused by running backwards on a brand-new motor with brand-new brushes unseated for reverse operation (which a Perm132 is NOT designed to do, but we thought it would last for a single race). Turned out, the brushes were just arcing and melted commutator strips together on the surface of the commutator, which short the windings.

 

[Green Machine]

So what...

the bike was a valiant effort to compete in this race...

dont forget it was just completed this morning...to compete 5 hours later after 5 hours of driving.

So it failed its first test...no suprises...what were the chances that it wins a race with no prior testing? I think around 50 percent...so lost a coin flip. even our hero physics is capable of losing a few coin flips...what about the next race? After lessons learned etc....who you put your money on? Next years race i would def know who i would bet on.

This bike is magnificent and should race again soon...this bike is a contendor...and it did great given it was just completed this morning...

I applaud the entire team and one of the most splendid threads i have ever read on ES....so what if the result wasnt cinderella....i never liked cinderella endings that much anyway.

I really am hoping this is not the last we see of this incredible effort.....damn...laguna seca is next weekend...remember the willow springs race was on a .6 mile go-cart track, not its famed course which fast rice rockets raced on today ...next weekend Laguna Seca will allow electrics to run on their big track...imagine that....i think Luke lives a couple hours away from Laguna Seca....

I was actually there today....and trust me....willow springs is no laguna seca....

 

[liveforphysics]

I'm applying to the Laguna Seca event right now.


Laguna is a big track. I'm going to see if I can tuck a 45kW brushless motor and monster Sevcon onto the bike by next weekend.


On top of that, I've got 2 full size motorcycles and 5 karts to help prep for that event. It's going to be a very full next week. Hopefully not as labor intensive as last week though, or I might die before the event comes on the 26th. lol

This is a fairly crappy site about the Laguna Seca event.

http://www.refuelraces.com/index.html

 

[knoxie]

Hey better to have died trying Great job Luke getting there in the time that you did was amazing and great fun to watch, the bike looks sick and will look better as it rusts, real mad max e racer, didnt realise you were running it backwards though damn they dont like it do they (made that mistake before) Consider this race the shakedown race, you are going to pwn the field with a brushless motor in there

I guess its still late there in Socal, get some sleep your going to need to keep your skills sharp for the rest of the week, the mishaps will only make the wins taste even sweeter!! your fast becoming a true e-building legend!

 

[flathill]

Look at high power loudspeakers. 10kw peak 1kw continuous is not uncommon on a single 21" woofer. The RMS limiters kick on after a half second or so. The RMS limiters are graceful, not an on off switch. The motor will fry without them. Quick acting peak voltage and temperature limiting make the system almost bulletproof if power tested/tuned under hard limiting conditions. Still you want it to sound good...the art of compromise. The system should still be able to fail.

 

[liveforphysics]

Hey better to have died trying Great job Luke getting there in the time that you did was amazing and great fun to watch, the bike looks sick and will look better as it rusts, real mad max e racer, didnt realise you were running it backwards though damn they dont like it do they (made that mistake before) Consider this race the shakedown race, you are going to pwn the field with a brushless motor in there

I guess its still late there in Socal, get some sleep your going to need to keep your skills sharp for the rest of the week, the mishaps will only make the wins taste even sweeter!! your fast becoming a true e-building legend!

Thank you for the kind words Knoxie. You're an international legend yourself you know.

Yeah, I'm thinking 45kw brushless. Will do the trick. I hope my nano's get here before Saturday.

 

[toolman2]

I'm applying to the Laguna Seca event right now.


Laguna is a big track. I'm going to see if I can tuck a 45kW brushless motor and monster Sevcon onto the bike by next weekend.


On top of that, I've got 2 full size motorcycles and 5 karts to help prep for that event. It's going to be a very full next week. Hopefully not as labor intensive as last week though, or I might die before the event comes on the 26th. lol

that sweet little brushless joby motor (from the first post) that was meant to go on this bike (as with any big rc type brushless) was allways going to be a massive effort to get sorted properly before being really viable to race -or even get off the mark at all without blowing all its controllers etc as we know. so to end up back with a simple (and normally reliable) brushed motor with only a few days to go was probably a fair call to make the race.

sounds like a similar (and highly entertaining) story may unfold again with Laguna Seca with the 45kw brushless, 7 other preps and 1 week to do it etc, but i think getting the big rc type brushless motors running reliably takes a lot more of a concentrated, long term steady effort to accomplish, and thats where myself and a bunch of others here could be of assistance -ei in the last few months splinteroz and myself got back to you hoping to take you up on your very kind offer of availability of sevcons from your people (no suppliers/support here in OZ for them) and the lend of a setup module, we both sent a bunch of pms your way to get it all happening and order a sevcon each without any response.

the big, high power density motors that we are all keen on, along with burties timing modules, etc, are exactly what we are working hard on and would have been a pefect match for an event and bike like this one, and i think by helping each other out, we could work our way through these challenges -i for one would be happy to slowly chip away for a year in my workshop with full load low rpm testing on say a collossus or turnigy 120 (that we have) and a sevcon or similar (that we dont) that will work for all these race applications, then bounce the recipe back your way.

that way if you want to bolt it all up in the van after days of frenzied allnighters on the rest of the bike, you can, knowing the critical motor/controller combination is something that has been developed by all of us with the time and long term effort required for reliable competition use..
-this way the public can be spared the boring and slow development of brushless motor control, and be more successfully entertained by your last minuet builds and crazy flipping off the bike vids

also, please tell me somehow the fine little joby motor you started this build with has is going to receive the time and effort it deserves, and isnt lost and forgotten in all this carnage :lol:

 

[Tiberius]

Hi Luke,

Hard luck, but it was a valiant try. Sounds like you've got a good basis for another attempt next weekend, though. Keep it coming.

Bolting together a machine the day before and testing it in the race - I would never do a thing like that.

Nick

 

[Miles]

What a pity.. Incredible effort to get it all done, though. I wish I had a tenth of your drive/energy

 

[full-throttle]

Sorry to hear about all the technical difficulties guys..

I'm applying to the Laguna Seca event right now.

Watching a doco on Laguna Seca MotoGP at this very moment - The Doctor, The Tornado and Kentucky Kid

I'm so envious! Wish we had e-bike races here in Australia..

 

[knoxie]

Make it happen !!! Would love to see Jester whoopin ass on his cruisers heck I would have a go but not sure if I got the skills at my age! ha ha but it would be fun to have a go

 

[Whiplash]

What kind of max speeds were you guys seeing? It seems like these motor failures must be from the single speed setups you all run. Every time you come out of a corner and lug the motor up to speed you are generating heat that will eventually heat soak and then kill the motor. I would think some gearing is in order or liquid cooling to handle the speed changes..

I read that you were worried about the brushes on your bike, I mostly was talking about the others that killed motors, I would not bother trying to put my $.02 in on your build, you are way beyond my skill level! Good job getting there at the very least!

 

[deVries]

Motor speeds weren't the problem at all for our bike. After around 15mph, our motors efficiency stays between 84-92% for the whole RPM range we were using.

Our motor also didn't die from overheating, it died from mechanical brush failure caused by running backwards on a brand-new motor with brand-new brushes unseated for reverse operation (which a Perm132 is NOT designed to do, but we thought it would last for a single race). Turned out, the brushes were just arcing and melted commutator strips together on the surface of the commutator, which short the windings.

LFP: "we thought it would last for a single race"

Why did you have to run the motor "backwards" in the first place? :?

What is the wheelbase of this bike?

Thanks.

Wow, 45kw next weekend... has ANY eBike had this kind of power before?

Gotta love this. I certainly am enjoying "the reads" of your race threads Luke. The R&D of eBike racing done right on the track with last minute AMAZING efforts & energy. You've got the gusto & spirit-force to do whatever it takes. Die hard battery!

 

[etard]

I was soo happy to see you guys show up for the race Luke, it was an amazing testament to the power of teamwork, maybe we should have an ES sponsored team build wars like Junkyard Wars and you guys go In like the home Reno teams and turn somebodies extra parts bins into viable ebikes. Just think what you guys could do at AW's house!

It was a valiant effort and I wish I had a support team of close talented team of friends to do the same, if even on a smaller scale. I think all of here wish we had that, that's why we are on here so much!

Having said that, I'm not certain you would have beat the fastest gasser, that guy was doing laps at least 10 seconds faster than Alex, who is no slouch. I'm sure your boy was talented and your bike extremely fast, so it would have been a good race, IMHO. I guess we will never know, but let me say this about that bike and rider: his bike was a modded beach cruiser frame with ALL bicycle components besides the final drive chain, which I can understand if you are putting out over 12 hp. I talked to those guys extensively about thier bike, it had Avid Elixir brakes which are very nice XC bicycle brakes and he experienced zero brake fade, amazing! He was also running 26" Hookworms on DH rims, which he had 2 flats with, so I would say he was pushing these tires beyond thier limits.

Favorite quote from Luke at the race when introducing me to his "jockey", "He is a soldier for the revolution.". Awesomeness!!

 

[nicobie]

Hearing about the brushes was, to me, good news. At least you know you are on the right track with a solid controller, batteries and (maybe) motor.

Years back when we were racing karts we had a few races at Laguna Seca. To be honest, It scared the shit out of me. Way fast with a couple super tricky corners.

 

[PaulD]

That's a bummer about all of the mechanicals, guys. Thermal management is the nemesis of EVs. Sounds like there were some really competitive e-bikes, we'll get those gassers next time!
oh yeah, big thumbs up to SoSauty for finishing with what must be a very efficient bike. Nice job with the heat sink!

 

[flathill]

hehe, racing will allways expose your weakness.
isn't timing on the perm variable for rotation?
from thunderstruck motors:

.The PMG 132 is a "pancake" style, axially gapped, neutrally timed, brushed, permanent magnet DC motor manufactured by Perm Motor in Germany. It is similar in design to the Lynch/LEMCO LEM-200 and Briggs & Stratton Etek motors.

It's high power, high efficiency and small size make it a good choice for small electric vehicles, motorcycles, electrathons, generators, go-karts and robots.

Recommended controllers include the Alltrax line of controllers, from 24-72 volts or Sevcon Millipak.

MUST be run in CW rotation !

The variable timing on the perm does not enable reverse rotation...the brushes are biased(angled) to work optimally in one direction. At low power you can expect the brushes wear out twice as fast in reverse.

Luke and crew: Love the longtail frame! The top tube extending all the way back to the rear triangle is super innovative/beefy. Much love out to all the soldiers for the revolution.

 

[John in CR]

Luke,
I'm just glad the trying is fun for you. I hope this is the end of brushed motors, since their pluses don't outweigh the reliability issues. Get everything sorted so we can do a race down here. 7 miles from my house, just off the highway to the beach is a top notch race facility with a cart track, a longer faster track for the cars, and even a drag strip. $4 entry and we can go practice any morning from sunrise till 11am, and track rental time for the races will be cheap.

A vacation in paradise with ebike racing during the middle of winter up north would be hard to beat.

 

[liveforphysics]

An event in CR sounds like paradise!

This bike is going to get sooooo much faster in the next week.

 

[bigmoose]

Luke, I think your battery for this one was the Turnigy hard case LiPo's? If so, how are those working out for you? Failure rate? Percentage going puffy?

 

[amberwolf]

I had not realized it was being run reverse; I must've misunderstood how the pics show it's mounted, because I woulda swore the arrow on it is in the correct rotation direction to drive the rear wheel.

The only brushed unidirectional motor I've ever worked with myself was one out of a very old drill I was trying to fix a long time ago; a "universal" motor with an odd looking barberpole-ish commutator. I only found out it was unidirectional by trying to run it in reverse, by making a switch for the field windings to swap which ends connected where on the rest of it, and getting LOTS of sparks and air so hot it was uncomfortable, just spinning it without even a load on it. I didn't really understand how the results related to the design, but I knew it was bad, and took out the reverse switch.

 

[fechter]

Too bad on the meltdown. Like they say:

If it doesn't kill you, it makes you stronger.

I've always though it would be a good idea to use a non-contact infrared thermometer aimed at the commutator on brushed motors. At those power levels things happen real fast though. Once you get an arc going between commutator segments, it goes into fireball mode probably faster than you can let off the throttle.

 

[liveforphysics]

Luke, I think your battery for this one was the Turnigy hard case LiPo's? If so, how are those working out for you? Failure rate? Percentage going puffy?

Never balanced, never set an LVC, I charge them at 2-3c from powersupplies, and they have always performed flawlessly and always deliver what they claim.

That said, John in CR had one of these packs just vent and melt down royalty unprovoked sitting on his desk, so use at your own risk. They are damn cheap, and damn day to build packs with, but things that randomly catch fire aren't good for all applications.

 

[Fizban]

Awe inspiring work sorry about the result I wish I had a fraction of your talent and dedication. So do we keep watching this thread for the Laguna Seca race or is there another thread dedicated to that ?