AussieJester
1 TW
..just relaying what has been done and learned already, by all means fit two motors power to ya...literally.
KiM
KiM
Starting my second RC build.
- Thread starter E-racer
- Start date
E-racer said:
I wouldn't be so much worried about it being high up, more that it's unsprung weight. It'll make the suspension less effective.
That said, It might not be a big enough deal to bother you.
Regarding "overpowered", as long as nothing's breaking and you can ride it properly, you're not overpowered.
It looks like it will be a fun toy.
E-racer
1 kW
NickW said:E-racer said:
I wouldn't be so much worried about it being high up, more that it's unsprung weight. It'll make the suspension less effective.
That said, It might not be a big enough deal to bother you.
Regarding "overpowered", as long as nothing's breaking and you can ride it properly, you're not overpowered.
It looks like it will be a fun toy.
I agree. I was on a Formula SAE team I know all about the downsides of unsprung weight. I think much more than 10lbs and I wouldn't have done it. Luckily these motors are made for RC planes... being light and powerful is their point. The 80-100 with a kelly controller is rock solid reliable and with the cycle analyst acting as a throttle interface I'm pretty sure i can tune the throttle pretty nicely. Ive ridden the 80-100 w/ a sensorless RC controller, throttle response and control is not their strong suit. I think it should be a lot of fun as well thanks!
Whiplash
1 MW
- Joined
- May 10, 2010
- Messages
- 2,906
WOW! Very interested to see the end result! should be a rocket to say the least! I would try to keep as much of the weight forward as you can to hopefully be able to USE the power it will have, with any extra in the rear, it will have a tendency to wheelie more than you might be thinking! Bikes wheelie way easier than scooters, the weight is placed very differently. That being said it looks KILLER!
E-racer
1 kW
Whiplash said:
Thanks! I've got to say having enough power to pull a wheelie whenever I want isn't necessarily a bad thing to me. This is a urban campus assault vehicle. I plan to be dropping stairs, ripping passed people in the grass, hopping up curbs, ect... That extra power will be welcome when climbing all the ridiculous elevation changes on my campus. I was clicking through your pics, You make some nice sub boxes, really impressive!
E-racer
1 kW
Whiplash
1 MW
- Joined
- May 10, 2010
- Messages
- 2,906
I love the design and the quality of the rendering! The only thing I MIGHT change is the center of gravity. If you plan on having the batteries in the box, the weight might be a little weird up that high, my brothers bike has only 10AH of 44.4V on a seat post rack and you can definitely feel it back there up that high. My commuter bike has the same AH in the center of the frame and you can't even tell they are there! If I where you, I would move the whole "body" down a few inches at least...
Other than that BEAUTIFUL!
Other than that BEAUTIFUL!
E-racer
1 kW
Whiplash said:
I'm assuming you are talking about lipo correct? I will take your advice for sure! thanks! I think I will move at least half the pack to under the tube and just extend (or maybe move) the body down like you were saying. Check back after the weekend I'll prob have it modified. Thanks for the encouragement!
E-racer
1 kW
Split pack. Anybody know how to use the wire/harness tool in Inventor?
E-racer
1 kW
-Bugsy-
100 mW
Are you planning on running a rear disk brake? The calliper mount seems taken up with other duties.
Am interested in seeing this build move off the design screen and into the real world.
Also props to defiantly forging ahead with a design others are saying won't work.
Subscribed..
Am interested in seeing this build move off the design screen and into the real world.
Also props to defiantly forging ahead with a design others are saying won't work.
Subscribed..
E-racer
1 kW
MakeTheNoise said:
I haven't fully detailed that rear brake mount yet because I haven't decided if I want to drop the rear brake or not. I know from my ESR the regen is sufficient under normal road circumstances. But from riding mountain bikes most of my life I also know its great to be able to lock that rear brake up and slide every once in a while. I just don't know yet. Right now that piece solely completes the 4-link for the chain drive in the model. I'm excited to move forward with the project. I have all the time I need with a water jet to cut almost all the pieces. I plan on manually machining the 1st stage reduction case. I'm a poor college student though so I'm selling off the contents of my garage to fund the project (scooters, gokarts, bikes, car parts, 2- stroke pipes ect... ). If any one wants a 250kw cont. electric bus motor and controller let me know... I've got one I cant afford a battery pack for :-D.
Whiplash said:Yeah, its actually really looking really good! I would extend the rear "fender" just for aesthetics but other than that it looks real good! Almost like the old cafe racer bikes!
BUILD IT! BUILD IT!
Modern Techno spin on a Cafe racer is exactly what I'm going for! Really due to the narrow 2.5" tires. I love these DH MTB parts though they are a cafe racers dream. I left the R. fender short because I figured if I case it down some stairs it may stay more intact if its smaller... A couple people have told me to make it bigger as well though so I may take that advice. I broke my collar bone in Jan so I need to take it easy right now n e way.
E-racer
1 kW
I made this for a live wallpaper for my new Motorla Atrix!
http://www.youtube.com/watch?v=rNX-uIlcjP0
http://www.youtube.com/watch?v=rNX-uIlcjP0
bandaro
10 kW
sweet ride! someone like's pro e/autocad
so a serious question, you will be able to make room to mount the gear between the spokes and rear disk? the caliper housing wont get in the way? i was thinking of going a similar way if i can not get a stronger belt for my crank drive. Secondly, what was the tooth count in the reductions?
so a serious question, you will be able to make room to mount the gear between the spokes and rear disk? the caliper housing wont get in the way? i was thinking of going a similar way if i can not get a stronger belt for my crank drive. Secondly, what was the tooth count in the reductions?
E-racer
1 kW
bandaro said:sweet ride! someone like's pro e/autocad
so a serious question, you will be able to make room to mount the gear between the spokes and rear disk? the caliper housing wont get in the way? i was thinking of going a similar way if i can not get a stronger belt for my crank drive. Secondly, what was the tooth count in the reductions?
Yea! I'm an Autodesk guy I use Inventor 2011.
I am going to try to make a rear caliper fit. I think it will be beneficial for sliding the rear end around although I will rely mainly on the rear regen brake along with the front. Ive got a Hayes Sole single piston caliper that is very narrow on the back side (pic below). I may end up milling a bit more off the back, should be a tight fit. Worse comes to worse ill drop the rear caliper and just use the regen in the rear. My reduction total is 8.5:1 that's geared for 55mph at 6000rpm on the 80-100. I'm really starting to consider a single stage reduction to save some cash.
spinningmagnets
100 TW
If you may actually make a custom frame, perhaps consider making the shock horizontal to the top-tube just under it. Then, square-up the bottom of the frame between the wheels, and that would make a great location for a squared battery pack between your ankles. It would place the battery weight fairly low.
If the squared-bottom frame caused too much flex in the main diamond (trapezoid?), perhaps add a left-side 45-degree flat-bar, leaving the right side open for a hinged access-cover to the battery. Just some thoughts...you have awesome drawing skills, thanks for posting!
If the squared-bottom frame caused too much flex in the main diamond (trapezoid?), perhaps add a left-side 45-degree flat-bar, leaving the right side open for a hinged access-cover to the battery. Just some thoughts...you have awesome drawing skills, thanks for posting!
E-racer
1 kW
spinningmagnets said:
I would love to have the funds to start from scratch and build a frame. I've been on the design team for 2 Formula SAE cars and nothing is more thrilling than modeling that entire car and seeing it come alive. Unfortunately E-bike are not what ill be focusing my life's engineering work on, custom vehicles have always been a hobby. If I ever do design a frame from scratch it will likely be one large extruded aluminum piece as a stressed member (swiss cheese and add appropriate placement points with a water jet). Of course it would have nice cnc'd billet blocks on each end with motor mount and steering tube ect. I would probably make a carbon fiber swing arm. I dunno.
I've often though about how I would design a production E-bike. Once I begin thinking about it I usually revert back to keeping this as a hobby. I'm thinking about going into the home geothermal heatpump system install business... Any thoughts?
ALSO
I think I'm going to go with a single stage reduction now. Originally I was going 2 stage because I was contemplating going up to 24s I think the max ill actually do is 14s so single is fine.
E-racer
1 kW
hawn, all the info for installing hall sensors in a turnigy 80-100 is on here. use search, there are different approaches to this and you'll have to decide how you want to do it. kellys stock have a 40,000 rpm limit so you take 40,000/6poles (in the 80/100)= 6,666 RPM max. Then take your motor Kv which is rpm per volt. you were talking about 6s so 22ish volts. 22*130Kv= 2,860 RPM way under 6600 ur good.
Whiplash,
My machine shop at school just moved into our fancy new engineering building! Great news! except all the machines have been down. I finally got in there and started to setup the CNC plasma (cutting line speed tests) ends up the POS torchmate machine we have got damaged in the move. So I've got to fix that machine and then ill be ready to start cranking on stage one. She should run in hopefully less than 2 months.
Whiplash,
My machine shop at school just moved into our fancy new engineering building! Great news! except all the machines have been down. I finally got in there and started to setup the CNC plasma (cutting line speed tests) ends up the POS torchmate machine we have got damaged in the move. So I've got to fix that machine and then ill be ready to start cranking on stage one. She should run in hopefully less than 2 months.
E-racer
1 kW
I explained the math in my previous post. This is easy math...
-130kv means the motor spins 130 rpm per volt. At 12s you are running 48ish volts. 48*130=6240rpm
-The 80-100 has 6 poles (12 stator slots) you divide the E-Rpm limit of the Kelly by the number of stator teeth. So 40,000/6=6,666 rpm max.
-6,240 (motors speed) is less than 6,600 rpm (max speed of the controller) so you DO NOT need the 70,000 limit. The standard 40,000 is fine for you.
-130kv means the motor spins 130 rpm per volt. At 12s you are running 48ish volts. 48*130=6240rpm
-The 80-100 has 6 poles (12 stator slots) you divide the E-Rpm limit of the Kelly by the number of stator teeth. So 40,000/6=6,666 rpm max.
-6,240 (motors speed) is less than 6,600 rpm (max speed of the controller) so you DO NOT need the 70,000 limit. The standard 40,000 is fine for you.
