New 24' slopestyle freeride build, getting serious!

Haha yeah I know...
Those old kitesurf lines are un-stretchable and the knot by itself was already quite strong, with a pattern preventing the mounts to twist around so the glue was only extra.

The shock mount on my 20' bike was holded like that, only with epoxy instead of PU. I had high quality epoxy around but the hardener leaked, and I tryed multiple times to source carboon wire but never found a cheap enough source.

This is just a "ridable mock-up" ;) I'll update tomorow morning! I cant wait to start making my custom frame, I NEED MOAR STEEL!
 
The mount is holding up fine, BUT I can't get a chainline to work well on this frame. So I just put a single chain going from the motor to the derailleur, and it works wery well! but the pedals are doing nothing now... One thing I would like to try on my next build is using the hub as a jachaft, with the pedals powering one side and the motor power being delivered directly to the rear derailleur on the other side! This would be neat, especially with a freewheeling motor like a MAC.

Oh and I put some DH 2,6 inchers knobbies on this rig, makes me much more confident in high speed offroad bashing!!

I have a new POV camera to play with, I have some bakyard wheelies video coming soon!

still waiting my steel order grrrr :x
 
[youtube]HNCsPwIvNLs[/youtube]

Video is curently uploading, raw from the camera.
should be done in 1h or so ~ Hope you like it!

edit : wow the sound got degraded so much by yt!
 
I will probably go with Rc lipo from the German hobbyking warehouse for my next pack.
The hardcase packs come in quite cheap for a respectable 16s 10ah pack, plus shipping is fast and cheap. However i'm pretty sure that my current sensorless controller has 63v caps, no workie! I have a hua tong 15fet on hand too, but I don't know the lvc... I would like to go with the hardcase because they offer some protection to the cells. but then my options are only 12, 16 or 20S...The best compromise would be 15s, right on the edge of a standard controller, but 14 would work too. I dont really need or want to go much over 70v fully charged, and I only need 2500-3000w continuous... Opinions?
 
I am amazed that glue is holding! LOL! Nice job on the quickie fix!
 
Yeah, well front brake on the right hand side is standard for motorcycling.

I've been debating doing the switch so I can do wheelies too! Back brake on the right side with throttle makes it VERY challenging to use the brake to prevent a tip over :p
 
It has a nice feature : the batt will fit inside the triangle, resting on the two front motor mounts. how many riding hours before destruction?
Click to expand...
You just gotta admire that kind of spirit...
I'm currently debating the pros and cons of a couple of different mid-drive approaches. One is to use a hub motor, as you are doing. The other would be to use a scooter motor such as a BMC, which would be somewhat more compact than the hub motor. Anyone have any thoughts on the pros and cons of either approach?
 
A hub motor has the interest to be extremely easy to gear to the rear wheel, and would work really really well on a high voltage setup. Plus it is super easy to build a multispeed setup if you stay below 5kW. On the other hand a BMC or Mac 2000w motors could be a really nice option, with a nicer powerband if you use single speed, may be easyer to mount to the bike, but need 1/8 gearing, wich is still easy to achive with karting chain and can handle way more power than typical bike chain.


7189812049_cb470b3e49_c.jpg


Latest frame design : I am going lightweight, with a smaller lipo battery. The chain arrangement has changed too, to have a good suspension comportment under motor load. This should work quite nicely and be simple to build. Still no tubes, this is pissing me off :evil:




Adam
 
Adam, i like your layout :D i can see some thought has gone into that regarding the chain pull and its influence on the rear suspension. I do think you need to raise the swing arm pivot a little more though, just enough to combat the sag from your weight, unless of course it has been drawn with the suspension loaded? in which case i think it is spot on! This will make a nice very useable bike that handles the transition from off the power to on it very well with minimal reaction from the chassis. I like how you have given priority to the motor chain and re-thought the pedal chain to accomodate this layout, Get it made!!

How about putting a fixed roller on top of the chain just above the swing arm pivot (the higher the chain is above the pivot the more it will try to pull the swingarm upwards when under power) this will keep the chain close to the pivot even under large suspension compression reducing the powers tendency to create squat and will help with keeping the chain at a more constant tension through the suspension travel giving the derailier an easier life with less chance of the chain jumping if the derailier cant react fast enough to keep the slack in check? Derailiers dont have very strong springs.

Your well on your way to a good design here Adam.
 
Tench said:
Adam, i like your layout :D i can see some thought has gone into that regarding the chain pull and its influence on the rear suspension. I do think you need to raise the swing arm pivot a little more though, just enough to combat the sag from your weight, unless of course it has been drawn with the suspension loaded? in which case i think it is spot on! This will make a nice very useable bike that handles the transition from off the power to on it very well with minimal reaction from the chassis. I like how you have given priority to the motor chain and re-thought the pedal chain to accomodate this layout, Get it made!!

How about putting a fixed roller on top of the chain just above the swing arm pivot (the higher the chain is above the pivot the more it will try to pull the swingarm upwards when under power) this will keep the chain close to the pivot even under large suspension compression reducing the powers tendency to create squat and will help with keeping the chain at a more constant tension through the suspension travel giving the derailier an easier life with less chance of the chain jumping if the derailier cant react fast enough to keep the slack in check? Derailiers dont have very strong springs.

Your well on your way to a good design here Adam.
Click to expand...


ahhhh my head... that was a long sentence! hheheh. good point though. Does anyone have experience of how guides like that handle the tention under power? I'm mainly asking in regards to efficiency... in my head it seems like putting a great deal of tension across it would create quite a bit of friction and other losses... if not though it'll really help my next build.

as usual bhz... love ya work. gearing your pedals up to the motor speed is a great idea.
 
Thanks for the advice, I totaly forgot about suspention sag :roll: let's say I had it planned in that draft ;) is 15-25% of sag reasonable?

I went out riding today, but I kept braking links on my chain... I think I should go with stronger chain with a single speed to the rear wheel and more volts but the same low gear to keep the brilliant torque, and use bike chain for the bike stuff! in the current configuration the bike pulls really well and is very controlable. 30-35mph top speed is fine for me, and single pedal speed is okay too. Ill see when I get my stuff to build the new frame I guess, but breaking chains all the time starts to be annoying :evil:

Adam
 
Just out of curiosity, have you considered using a belt final drive? Such as the Gates Carbon Drive?

http://www.carbondrivesystems.com/
 
sn0wchyld said:
Tench said:
Adam, i like your layout :D i can see some thought has gone into that regarding the chain pull and its influence on the rear suspension. I do think you need to raise the swing arm pivot a little more though, just enough to combat the sag from your weight, unless of course it has been drawn with the suspension loaded? in which case i think it is spot on! This will make a nice very useable bike that handles the transition from off the power to on it very well with minimal reaction from the chassis. I like how you have given priority to the motor chain and re-thought the pedal chain to accomodate this layout, Get it made!!

How about putting a fixed roller on top of the chain just above the swing arm pivot (the higher the chain is above the pivot the more it will try to pull the swingarm upwards when under power) this will keep the chain close to the pivot even under large suspension compression reducing the powers tendency to create squat and will help with keeping the chain at a more constant tension through the suspension travel giving the derailier an easier life with less chance of the chain jumping if the derailier cant react fast enough to keep the slack in check? Derailiers dont have very strong springs.

Your well on your way to a good design here Adam.
Click to expand...


ahhhh my head... that was a long sentence! hheheh. good point though. Does anyone have experience of how guides like that handle the tention under power? I'm mainly asking in regards to efficiency... in my head it seems like putting a great deal of tension across it would create quite a bit of friction and other losses... if not though it'll really help my next build.

as usual bhz... love ya work. gearing your pedals up to the motor speed is a great idea.
Click to expand...
Just read it back, i see what you meen!! well, i was getting exited!! :D
 
bzhwindtalker said:
My sensorless 12 fet is toast :( I hated the 5km with no E-power, this thing is so ineficient to pedal!!
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bugger mate! what happened? you could try getting a small 6 fet sensorless as a backup?
 
Actually it is still working! I got it all apart and removed any unnecessary wires, just to keep power leads, phases, halls and throttle. The fets are IRFB 3XX7, I can't really read what's in between.
But damm I need my new chassis done, this one sucks and looks awfull.

Adam
 
Bike back rolling, evry time I get riding again after a few days without using it, I am amazed at how good this thing wheeleys 8) ultimate backyard fun! My goal for the end of the summer was to be able to do the whole length of my backyard on the back wheel, I can regulary pull 1/2 of it (40m long backyard... :p ) Some more training will do the job! Left hand rear brake is absolutely perfect, I think this should be standard on all powerful bikes.
 
How do you think one of the mini hub motors, such as a Cute, would work with a setup such as yours? Would the 500w or whatever the Cutes do be sufficient when going through the gears?
 
That's something I would like to try, but the next on my list is either a Magic pie or a fast MAC, when I will have the new frame ready I will be able to switch between motors easy. The magic pie will probably be too much hassle because of the huge diameter.
A MAC with removed flanges could be GREAT! The question is, do they handle 2000-2500w cont/3500 peak over 550wh?
 
I've no experience with the MACs, but from what I vaguely recall reading, believe that you wouldn't want to go much past 2.5kW.
 
bzhwindtalker said:
That's something I would like to try, but the next on my list is either a Magic pie or a fast MAC, when I will have the new frame ready I will be able to switch between motors easy. The magic pie will probably be too much hassle because of the huge diameter.
A MAC with removed flanges could be GREAT! The question is, do they handle 2000-2500w cont/3500 peak over 550wh?
Click to expand...

im a fan of the pies, but i would not use one here.. i reckon you could get a fair bit more power than usual from any hub this way, via revs, so you could use a real small light one at higher rpms that would lessen the loads on everything. :wink:
 
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