E-Bike Racing: 2011 World Challenge

[bzhwindtalker]

You forgot to say to remove brakes
who need them anyway

 

[REdiculous]

..plastic pedals, racing seat, wooden seat tube, ditch the CA/display, lighter neck and handlebars, lighter frame..

 

[GrayKard]

Arlo,
I see you haven't even attempted to "LOSE" the weight on your build.

Friendly suggestions include:
#1 cut out every other spoke
#2 what do you need that heavy down tube for...cut it out.
#3 cut off 1/2 of your handle bars/remove the grip from the remaing one
#4 remove the seat
#5 sandblast off all the heavy paint
#6 drill holes in every thing thats left. such as-frame members, axels, nuts, cable housings, rims....be creative.
#7 re-wire with "aluminum" wire.
#8 replace all duct tape on batteries with scotch brand celophane

Just a few helpful suggestions from a fellow competitor

(ps-no one should take this serious!)

Don't forget to make a video of the weight mods so others can learn.

If you use a backpack for your batteries will it be weighed as a unit just like it's a battery box? Do the bikes get weighed before every heat?

Gary

 

[dogman dan]

As long as you don't plug them in, carry all the weight you want in your back pack. Plug in, they are part of the bike.

I love the idea of the trials course! The more kinds of races the more fun. Could even include some goofy activities you have to do halfway through, like mount a tire and inflate it or whatever, just for the entertainment value of it.

 

[Arlo1]

I dont know how to get it down to 70 lbs

Perfect This means the event won't just be the 2011-world-enter-my-normal-bike-and-kick-ass, it will still be the 2011-world-Challenge for you as well. I was a little worried you were going to be able to just enter your bike as it sat and kick some ass. At least this way you get some weight puzzles to creatively solve.

The problem is luke that damb x5 weighs so much! I guess I will start drilling holes in it! I think I might be over 80 lbs now with the tires!

 

[Arlo1]

Arlo,
I see you haven't even attempted to "LOSE" the weight on your build.

Friendly suggestions include:
#1 cut out every other spoke
#2 what do you need that heavy down tube for...cut it out.
#3 cut off 1/2 of your handle bars/remove the grip from the remaing one
#4 remove the seat
#5 sandblast off all the heavy paint
#6 drill holes in every thing thats left. such as-frame members, axels, nuts, cable housings, rims....be creative.
#7 re-wire with "aluminum" wire.
#8 replace all duct tape on batteries with scotch brand celophane

Just a few helpful suggestions from a fellow competitor

(ps-no one should take this serious!)

Thanks thud. I think if I just remove the frame, bars and the forks I will be in the limit. SO I will just have to put stunt pegs on the front wheel and I will put clip ins on the rear wheel and all else in a back pack and giver my abs need a work out anyway

 

[liveforphysics]

Arlo,
I see you haven't even attempted to "LOSE" the weight on your build.

Friendly suggestions include:
#1 cut out every other spoke
#2 what do you need that heavy down tube for...cut it out.
#3 cut off 1/2 of your handle bars/remove the grip from the remaing one
#4 remove the seat
#5 sandblast off all the heavy paint
#6 drill holes in every thing thats left. such as-frame members, axels, nuts, cable housings, rims....be creative.
#7 re-wire with "aluminum" wire.
#8 replace all duct tape on batteries with scotch brand celophane

Just a few helpful suggestions from a fellow competitor

(ps-no one should take this serious!)

Thanks thud. I think if I just remove the frame, bars and the forks I will be in the limit. SO I will just have to put stunt pegs on the front wheel and I will put clip ins on the rear wheel and all else in a back pack and giver my abs need a work out anyway

That's the spirit!

 

[liveforphysics]

If you can take that x5 to a lathe, and find ways to shave a few pounds off the stator of that pig, the techniques and modifications you do are going to be super valuable to everyone with an x5. I can't imagine there is anyone in the world with an x5 who wouldn't be happy as a clam to find a way to make their hub a little lighter . And even more desireable if your mods both make it lighter, and have higher power handling limits.

Since comfort isn't a concern for a racebike, perhaps replace the steel riser handle bars with a straight carbon fiber tube that gets clamped directly to the head set. Should shave a couple lbs. Tubes are available for $40-50.

Since I know you've got killer DIY skills, and a slow air-leak doesn't matter for a race bike, you could install motorcycle rim valve stems, rubber cement the tires to the rim after rubber cementing in a sealing layer over the spoke nipple area, and run tubeless. Should drop a couple lbs.

Shave the tires on a lathe to take off the extra tread you won't be needing for a race that only lasts 12.5miles.

Pull the controller out of the case, and heat-sink the FET bar right to the frame of the bike to be the heatsink. Locate things in a way that the wire lengths are minimized.

Then, of course the classic stuff, like drilling holes in everything, since your bike is made to be strong enough to land 10ft jumps, and you will only be running on smooth asphault.

If anybody can do it, I've got total confidence in you Arlo.

 

[AussieJester]

...or...could just pop on an RC motor and 1/2 the weight of his bike

LOL@Thudsters suggestions, seeef you will need the competition to fail for
you to triumph Thud.

KiM

 

[liveforphysics]

This may be something that folks running scooter tires (made for running tubless) will be interested in.

http://greenfishsports.com/product/363_393_532-tubes-accessories/4513-no-tubes-bike-tire-stans-no-tubes-plus-four-29er-tubeless-system.html

This enables you to not need tubes.


Or, for many folks who run bikes that use super heavy wall tubes and rim strips and slime etc etc, these things can weigh 3lbs alone!

For someone who currently runs heavy duty tubes and/or slime etc, and looking to shave a very easy 5lbs off the bike, and have it all be rotational mass, go for a set of latex tubes:

http://www.cambriabike.com/shopexd.asp?ID=29514-Michelin+Aircomp+Ultra+Light+Latex+Bicycle+Tube

 

[dogman dan]

Very true. In my neighborhood, I've been known to put close to a quart of slime in one bike. We have the extreme thorns here. 2 pounds of slime per tire is not unusual for me. That specialized of mine should weigh 35 pounds, but slime, fat tubes and 2.75 in tires add lots of weight.

Now that you have changed the name, just stick to the 70 lb limit, and allow for an X5 class with a different weight limit if there is more than 3 guys showing up to run in it.

There's always the Death Race for those with unlimited race bikes.

 

[liveforphysics]

, and allow for an X5 class with a different weight limit if there is more than 3 guys showing up to run in it.

Don't you think it would be much more fun for the X5 guys to get to figure out clever weight reduction methods to make 70lbs rather than just go into a fattys-only class with just a couple opponents?

With Arlo's X5 bike at 78lbs, and NorCalTuna's X5 bike at 76lbs (even using fatpacks rather than LiPo), it seems completely reasonable they can make the same 70lbs limit if they make even a mild effort to build a race-specific entry rather than just running their normal streetbikes as they sit.

I'm just thinking with track rental in the many hundreds of dollars an hour range, and a class taking about 30minutes to run, keeping the number of classes down will save me cash!

 

[NorCalTuna]

Oh, my current bike could make the show with a few changes, I'd think. BTW, I just rolled my bike onto the scale casually because I finally got one, for $1.50, at the sal. I wouldn't call it a tech weight, but I did put the opposite end on blocks so it wasn't vectoring weight to the downhill end.

Diet wise? I have some ideas for errbuddy. I'll share them for thought food:

Pulling off idle stuff- bag with tools, pump and mount, the CABLE LOCK!, reflectors, seat cover, kickstand.... Honestly, none of those things belong on the track anyhow.

and then, the 26" wheels with slime tube rear and bell "self sealing" tube in front can go and a lightweight 20" setup with very thin or tubeless could run for the race no problem and definitely give some welcome oomph.

The 14 ish lb LiMn packs could be swapped for about 8lb. lipo, but it really needs more battery than that even now.

And then, the x5 can be obviously lightened with "speed holes" or radial speed slots (with airfoils?) at the sacrifice of wet reliability and dust resistance.

end rambling on how to make a typical 26 make the show.

That said, the hub motor isn't really THAT big of a weight disadvantage once the drive comes into play, it would seem. I still believe that they should be included somehow or given another class if this seems to be an ongoing problem.

My biggest concern is that suspensions aren't really in the cards, and for a possibly arbitrary reason. The suspension doesn't push, it only maintains, and if it isn't necessary, then the weight is a disadvantage. One the rider should choose if they wish. Rigids just aren't all that to ride at high speeds, and a lot of forum members have built suspension bikes for that reason. Yes, karts don't have shocks (they have torsion bars) but pretty much every motorbike thats worth it's salt- a world class anything- has a suspension beyond the tires and some frame flex. Why ask people to go backwards?

 

[liveforphysics]

Why ask people to go backwards?

Look at a road racing bike, even an old beater.

The frame/fork design is all the suspension you need for a glass flat kart track. The curve of the fork, the bow of the stays, it's all designed with the same flex ideas in mind as the frame of a kart.

With a BMX, the frame is very rigid, so the tire and riders legs become the bulk of the suspension.

Or, if you want suspension badly enough, then sacrifice some battery capacity to ensure you get the most cushy ride around the track with a peak rapid surface variation of maybe 3mm. Or the indoor track with a polished smooth concrete floor at maybe 0.5mm max variation.

 

[liveforphysics]

And it's been mentioned all ready, but keep in mind that guys bomb down giant mountian passes on <10lbs roadbikes with no suspension on public winter cracked and damaged roads at 50mph stacked just a few feet apart with a cliff on 1 side in groups of 100+ riders. Tour de France of course. And even in many hours of exhausted riding with burned out legs and stressed out brains, they manage to keep it together (most of the time).

I think we can manage a group of maybe 10-15 riders going 25-30mph with soft grass and rubber tires to cushion wrecks if the lack of suspension on the glass smooth track is too much to handle for someone.

 

[SoSauty]

NorCalTuna,

don't know even an estimate how much weight you save by drilling your x5 full of holes, yet seems your chubby bike could come in at a slim mid or maybe lower 60 lbs. Hmmm, maybe we should consider 30kg limit rather than 32kg

Hey, does anyone think a folding bike class, I could sneak a 20" on a flight in a Samsonite Oyster suitcase (minus the battery) has any possibility? I can't see myself racing the main event but could make the for fun classes. Would this appeal to folks flying in from out of state, or from out of states, who want a 2nd bike to run or just want to show up for fun races and spectating?

 

[Arlo1]

I build my own carbon fibe! Ok so can we post the set in stone rules before I start drilling? And how manly laps? I need to know in miles or km how long the race is and how many motos there are. Then as usaul I will start my build!

 

[pdxebiker]

Why not come to next years ePower Challenge? Here's a writeup of this year's event.

http://pdxebiker.blogspot.com/2010/06/racing-ebikes-at-least-my-jacket-was.html

 

[Tiberius]

Why not come to next years ePower Challenge? Here's a writeup of this year's event.

http://pdxebiker.blogspot.com/2010/06/racing-ebikes-at-least-my-jacket-was.html

Wow, good idea. I thought all our problems were solved.
Why aren't these guys posting on ES; why didn't we know about this?

But when I was digging around for the rules, I got to this.....http://www.ohpv.org/HPC/page22/page21/page21.html

Its not quite the same thing. It's got to worth talking to them, but we may be on a different wavelength.

Nick

 

[REdiculous]

Are you guys gonna start a collection to pay for track time? Even if I can't make it I'd try to contribute something..just a half-random thought. later

 

[dogman dan]

Ahh yes, I hadn't considered the track time cost. But if there is some track room, I suppose two classes could be run at the same time. To clarify what I was thinking some, you keep the 70 pound limit. If you can get your x5 bike down to fighting weight great! But if you actually do have 5 or more that just can't get it down to 70 pounds, Let them run thier class at the same time as another class if there is enough track space. Start class one, half a lap later start class two. Maybe the track is too short to do that. I think it would work in Tucson with .8 mile track as long as you kept it down to whatever number the track can race at one time. If a 5 person heavy class doesn't pay for the track time with thier entry fee, shorten thier race till it does.

One of the reasons I see exluding heavy and or street bike type characters is bad, is that you get no entry fees from em. One of the reasons the death race can afford the track time is 70 riders x $15 plus about another 30-40 at $10 to see the bikes in the pits. So you see, it may be to your advantage to include everybody, at $20 a head. Get 50 riders at $20 an entry and you have the first thou in hand. 15 riders, and you need to charge a lot more to raise a thou for track time. I would assume you could get some ES donations for the rest. No way do we expect you to pay the track time out of your pocket.

 

[Arlo1]

I will lighten my bike to be able to enter even though its not going to be easy! I would rather just have an "open" class that has bare minumum for rules eg. Must have functioning peddles, must wear a snell 2000 or dot helmet, Must run x number of time??????? Eg race is 10 minutes + 2 laps?

 

[fizzit]

Just wanted to add, it needs a e-scooter class

 

[liveforphysics]

Just wanted to add, it needs a e-scooter class

At $800+ per hour for track rental, better make sure you get enough other guys with e-scooter interested

However, if your scooters can run on grass+asphault, you can run all you want for free on a track we setup ourselves.

 

[AussieJester]

And it's been mentioned all ready, but keep in mind that guys bomb down giant mountian passes on <10lbs roadbikes with no suspension on public winter cracked and damaged roads at 50mph stacked just a few feet apart with a cliff on 1 side in groups of 100+ riders. Tour de France of course.

Hardly 'WalMart' quality bikes though Luke, one wheel alone on a bike used in the "Tour de France" would cost more than the entire bike most on ES use as a base for their electrics, Thankfully this wont be a problem Luke :lol: i don't forsee high speeds being anything exceptional with the EBRR 1000watt limit. :wink: :lol:

KiM