Luke's race bicycle of Doom 2.0

[liveforphysics]

It lives.

It rips.

Motor still gets overheated in about 5mins.... kinda pissed about that, but after hours of professional Sevcon dyno tuning, it runs and doesn't fault out. The controller gets warm, the battery stays cool, the motor gets flesh-burning hot.

Maybe the gearing needs optimization. What rpm were you making peak power? Peak power and peak efficiency are almost never coincident. Maybe you need to be in another band.

Glad to read you guys finally got the sevcon dialed.

Yeah, I also think that's part of the problem. I wanted to try to calculate the longest straight at the grange track, estimate the speed I would enter it, and gear the bike so I wouldn't be running out of gear, but it looks like I'm going to need to re-gear it a bit to help the motor survive. Im running a 24t front and 71t rear right now with a 24.1" diameter tire, and a 6,500rpm motor RPM limit. I'm going to try throwing a 20t or 19t on the front and see if the motor temps drop.

 

[voicecoils]

Tell me you're going to throw some internals in those Fox 36 forks!? 8)

Otherwise you must be hoping to win a prize for 'most expensive rigid fork' :lol:

Good luck racing.

At TTxGP Australia this year we found that he who melts motor least often, crosses finish line more often.

 

[bigmoose]

Congratulations! Now put some temp sensors/management on that beast, run with the pack for 90% of the race, then... sprint out to the horizon on the straights...

 

[Ypedal]

Awsome !!!

In the heat of the moment rubbing elbows on the track, self control is rarely an option so the bike needs to be built with some realistic robustness lol.. specially in the hands of luke.

I hate fragile builds.

 

[GCinDC]

I'm totally psyched for this! Woohoo! Kick some stink bike ass! Are you gonna actually sleep the night before the race?

What's the rear rim? Doesn't look as manly as the front...

 

[Whiplash]

Anybody have a link to the Grange race? I must have missed it, I really need to see this thing in action! I am willing to bet they have no idea what they are up against if it survives the race! AREA UNDER THE CURVE BABY!!

 

[liveforphysics]

Tell me you're going to throw some internals in those Fox 36 forks!? 8)

Otherwise you must be hoping to win a prize for 'most expensive rigid fork' :lol:

Good luck racing.

At TTxGP Australia this year we found that he who melts motor least often, crosses finish line more often.

Nope, I like them better rigid, not damped enough otherwise. If somebody makes a bicycle fork with internals that are suited towards road racing rather than bumping around off road, I will put those internals in it.

Congratulations! Now put some temp sensors/management on that beast, run with the pack for 90% of the race, then... sprint out to the horizon on the straights...

Thank you my man, never would be here with out you. We are going to bond a temp sensor to the motor today, and try to program the Sevcon to dial current back as the motor starts to reach melt-down temps.

Awsome !!!

In the heat of the moment rubbing elbows on the track, self control is rarely an option so the bike needs to be built with some realistic robustness lol.. specially in the hands of luke.

I hate fragile builds.

Ehh, I don't know if I would call it "fragile" exactly... but it's far from bullet proof. The temp sensor linked to the controllers current thing will hopefully make it bullet proof.

I'm totally psyched for this! Woohoo! Kick some stink bike ass! Are you gonna actually sleep the night before the race?

What's the rear rim? Doesn't look as manly as the front...

I've NEVER got to sleep the night before any race, I always think it will be different each time... but Murphy generally likes to strike at the last possible second with something devastating that requires working all night to try to patch it up enough to run the next day. lol

That rear rim IS a serious potential failure point. It's a $7.99 rim, single wall, non-eyelitted, pined rather than welded, total piece of k-mart junk. I was planning to run the 20" rims (which I have some excellent quality stuff) with the pirelli tires on them right up until the last minute, and tried to scratch together a 24" setup with the parts I had available. I'm REALLY hoping it doesn't fail. lol

Anybody have a link to the Grange race? I must have missed it, I really need to see this thing in action! I am willing to bet they have no idea what they are up against if it survives the race! AREA UNDER THE CURVE BABY!!

Grange raceway kart track in SoCal, oct 22nd, starting practice at 7-8am or something. It should be a pretty good event.

 

[nicobie]

The temp sensor linked to the controllers current thing will hopefully make it bullet proof.

Now you're talking!

If you can get that expensive controller to do this, It will be worth every penny you spent on it.

I loved it when you said "not quite 11 hp".

 

[ajtest]

25S on a Methods controller!

Not something he sanctions!

Andrew

 

[liveforphysics]

25S on a Methods controller!

Not something he sanctions!

Andrew

This is a Sevcon gen4.... The little hubmotor bike runs a methods controller on 24s.

 

[Ypedal]

roughly how expensive are those sevcons ?

 

[liveforphysics]

roughly how expensive are those sevcons ?

http://www.electricmotorsport.com/store/ems_ev_parts_controllers_sevcon_gen4_72-80_550.php

And, it's worthless as it arrives. You need the $900 programming interface before you can even make it turn-on. Then you're going to need many hours of somebody who knows exactly what they are doing to end up with something that can actually make the motor spin and not fault every 2 seconds.

Basically, an epic PITA.

 

[Ypedal]

Holy Shit !!!.. unless i had a fleet setup that i could replicate once figured out.., major pass...

 

[bigmoose]

I better make sure my advice didn't introduce a fatal failure mode that makes the Sevcon barf. If only one TC and it fails open will the Sevcon fault? How can we add redundancy? 2 Failure tolerant for stuff that can inadvertently fault you out, I say!

... there! now I cannot be responsible for a race DNF that comes from the thermal protection scheme... that I recommended ...not I would hate to see our ES "friends" appearing over the horizon with tar and feathers for me. :wink:

TO LUKE!

 

[liveforphysics]

I better make sure my advice didn't introduce a fatal failure mode that makes the Sevcon barf. If only one TC and it fails open will the Sevcon fault? How can we add redundancy? 2 Failure tolerant for stuff that can inadvertently fault you out, I say!

... there! now I cannot be responsible for a race DNF that comes from the thermal protection scheme... that I recommended ...not I would hate to see our ES "friends" appearing over the horizon with tar and feathers for me. :wink:

TO LUKE!

My Moose Man, anything that were to go wrong, no matter who suggested it, is 100% my fault, and I would accept all the responsibility and shunning.

Likewise, if anyone ever came over the horizon with tar and feathers for you my friend, the lucky ones would find themselves waking up disoriented a few hours later with neck bruising that curiously matched up with my forearm bone shape.

 

[rodgah]

hey Luke,

congrats on getting a sevcon running.....

Why focus so much on gearing like you would if it were a machine capable of keeping within its thermal limits. If the shortest gear ratio you can use is still more than 40mph, then you know your still faster than the stink bikes and instead kill them out of the corners with the brutal torque. Atleast then you can ride it as hard as you want (assuming this solves your motor temp issues) and you might finish a race. Besides..... which bike 'looks' faster.......one travelling 10mph faster or one that wheelstands like a crazy stallion.

 

[liveforphysics]

hey Luke,

congrats on getting a sevcon running.....

Why focus so much on gearing like you would if it were a machine capable of keeping within its thermal limits. If the shortest gear ratio you can use is still more than 40mph, then you know your still faster than the stink bikes and instead kill them out of the corners with the brutal torque. Atleast then you can ride it as hard as you want (assuming this solves your motor temp issues) and you might finish a race. Besides..... which bike 'looks' faster.......one travelling 10mph faster or one that wheelstands like a crazy stallion.

Yeah, totally agree. We didn't even know the KV of this motor (it's a custom wind) when we first took a shot at the gearing, so we just picked a sprocket setup I had laying around and gave it a shot to get a little data. Now that we have a pretty good idea of the motor's characteristics, we are dropping from that 24t front to an 18t front, and the motor should have a lot easier life, and the bike should be more fun to ride.

 

[liveforphysics]

So, the bike has about 5 miles total on it. Got a flat as soon as I made my second ride on it. Fixed it, set the pressure back up to 65psi, went to rip again, and just ROLLED THE HOOKWORM OFF THE RIM... Thank God for good gear, I'm only bruised up, bike is mildly damaged, but thankfully didn't fall on the controller side.

That's 2 tire related failures in 5 miles of hard riding... With the motorcycle tires, never had ANY ISSUES EVER IN MY ENTIRE LIFE OF RACING.

On top of that, after 5miles, the center tread of the hookworm is all ready scrubbed down to almost smooth.

These things are NOT MADE FOR POWERED RACING.

I would need to re-weld the bottom bracket to raise it up if I want to run my 20" wheels with the pirelli tires, because I set the frame up for bicycle tires...

Racing on bicycle tires cornering at these speeds at knee-grinding lean angles when you're 235lbs does NOT work. Your tires will randomly fail every few miles.

Who makes a rule against having the proper equipment needed to safely race? It's as stupid as banning helmets or gloves or quality brakes or something...

 

[gensem]

Bloody hell Luke.. how much power where you pushing?

19" inch moto rims maybe?
Its going to be a mess. -.-

Glad you are not hurt, I was dumb last week and im hurt. hehehe

 

[voicecoils]

Glad to hear you're OK.

There's a reasonably large variation in fit between different bike tyres and bike rims.

I suspect you've got a rim that's a bit small and with poor quality lip to hold the tyre bead.

My current choice of ebike rim in 24 or 26" are the Sun Ringle MTX 39.

I measure 524mm from outer edge to edge, and they have a decent lip to hold the tyre bead.
They're also welded, have eyelets, a strong profile and mine weighs 820g.

Any other 24" wheels around you can try using? You should find the Hookworms difficult to mount without 3 strong tyre levers and a good bit of leverage. Otherwise the fit is too loose.

 

[bigmoose]

OK, with the race this weekend we need to think like the motoGP boys with traction control and anti wheelie control... can that Sevcon modulate the max current versus motor speed? Can you input a limiter map? With the new gear ratio and the mass of the bike we are have a factor of two more torque where the tire meets the road than our current system can handle.

 

[flathill]

So, the bike has about 5 miles total on it. Got a flat as soon as I made my second ride on it. Fixed it, set the pressure back up to 65psi, went to rip again, and just ROLLED THE HOOKWORM OFF THE RIM... Thank God for good gear, I'm only bruised up, bike is mildly damaged, but thankfully didn't fall on the controller side.

That's 2 tire related failures in 5 miles of hard riding... With the motorcycle tires, never had ANY ISSUES EVER IN MY ENTIRE LIFE OF RACING.

On top of that, after 5miles, the center tread of the hookworm is all ready scrubbed down to almost smooth.

These things are NOT MADE FOR POWERED RACING.

I would need to re-weld the bottom bracket to raise it up if I want to run my 20" wheels with the pirelli tires, because I set the frame up for bicycle tires...

Racing on bicycle tires cornering at these speeds at knee-grinding lean angles when you're 235lbs does NOT work. Your tires will randomly fail every few miles.

Who makes a rule against having the proper equipment needed to safely race? It's as stupid as banning helmets or gloves or quality brakes or something...

[/img]

If you don't have time to switch to the pirelli's maybe try tubeless tire glue and a slightly larger innertube. Also make sure your tube is slightly inflated when you first install it so it doesn't get twisted. Also more pressure. You may have a better chance of seating the bead. Maybe the cheapo rim isn't helping either....

 

[liveforphysics]

Yeah, I'm going to try some tire-bead glue. Hopefully it helps.

 

[hillzofvalp]

liveforphysics: which bms and psu are you using?

 

[amberwolf]

BMS? LFP? :lol: ROFL!

(he *might* be using Methods' LVC/HVC boards, the ones I call PackWatchers, but I doubt anything else)

AFAIK the charger he's using is a large lab supply (similar to my Sorenson DCS 55-55), probably in series with one of the HP 3KW supplies, both running off 220VAC.