Twin motored PK Ripper--A little over the top!

[deecanio]

the 203s are sweet matt,they look massive on 20's :wink: uber cool,with your braking system you'll be set, i run them on the stink with hayes "nines" hydraulics and they're awesome, although i only had 160mm cable previously to compare to :lol:
I have a question, with the throttleboard limiter being on the fly, and i think Richard said 5a at minimum setting? if my packs 50v but my setting is 5a doesn't that mean i'm running a 250w system? (uk limit) that would make me "legal" no?
By the way Matt, again super video, it shows me im going to really enjoy my bike this year

Cheers,

D

 

[recumpence]

Here is a walkaround video so you guys can get a better idea of the system as a whole.

[youtube]N2sSgJ3QUDQ[/youtube]

Matt

 

[gwhy!]

I have a question, with the throttleboard limiter being on the fly, and i think Richard said 5a at minimum setting? if my packs 50v but my setting is 5a doesn't that mean i'm running a 250w system? (uk limit) that would make me "legal" no?

this country stinks D I think its 250w on a tandam and only 200w on a normal bike

 

[recumpence]

I have a question, with the throttleboard limiter being on the fly, and i think Richard said 5a at minimum setting? if my packs 50v but my setting is 5a doesn't that mean i'm running a 250w system? (uk limit) that would make me "legal" no?

this country stinks D I think its 250w on a tandam and only 200w on a normal bike

Wow, we (I) have a 10kw limit.

Matt

 

[liveforphysics]

Judging from the video, your bike is faster than mine. The reason? Lower COG.

You did such a fantastic and refined job on your bike Matt. Huge respect to you.

-Luke

 

[etard]

Yay! Nice to see the Ripper on the streets. I find the sound soothing, even if the bike isn't. :wink: Do you ride mostly sitting down? Video of jumps next? :lol:

 

[swbluto]

Judging from the video, your bike is faster than mine. The reason? Lower COG.

You did such a fantastic and refined job on your bike Matt. Huge respect to you.

-Luke

Faster as in higher average acceleration, right? I remember some tales of you approaching a hill at 55 mph.

 

[liveforphysics]

Yes. I should have said faster accelerating.

This is because there is a speed range in which we both are not power limited, but chasis limited as to the amount of torque we can apply to the rear wheel.

As far as overall top speed goes, I have GPS confirmed 59mph with my setup, but top speed stuff is kinda lame. Acceleration is where all the fun is, and he has me beat, at least for 0-30mph or so. After that, it's going to favor whom ever has a better power to areodynamic drag ratio. His low to the ground BMX frame will also have a nice advantage with lower areo drag, so I really don't know which machine is faster in that respect.

If his bike were to race Jozzer's duke, my money is on Matt's bike easily being quicker up to 30-40mph.


Don't worry though I've got some new plans brewing

 

[recumpence]

To give you an idea of the torque this thing has, I was trying to do a burnout today. I was puting all my weight on the bars by laying on them with my waist. I hit the throttle and got a bit of wheelspin, then the bike wheelied with my full weight on the bars.

Oh, also, my cells are waking up. My accelleration and wheelie tendency is higher now. Not hugely, but pretty noticeable. I need more cells to take full advantage of the 30 to 40mph range.

I have no interest in going 50+mph. I like accelleration!

Matt

 

[Ypedal]

nothing like a healthy competition to move R&D along !

 

[12p3phPMDC]

The bike is awesome man. Beautiful machine!!

 

[Lucky_Hoodlum]

nothing like a healthy competition to move R&D along !

I wonder if we could get liveforphysics on a plane or Matt on plane with their rides for a head to head show down! I think Matt would have line honours in accelration on the fence to to which would have top end which is not really most impressive to myself accelration is the fun i think.

I guess we should also get the Doctor bass to tag alone to show how much faster rc motor is to hub hehe

 

[GGoodrum]

Matt, what size #25 sprockets are you using on the drive?

This really is a good-looking setup.

-- Gary

 

[methods]

Judging from the video, your bike is faster than mine.

You should get used to saying that. :wink:
My 8 speed 3220 will accelerate harder and to a higher top speed than both your double-motor turkey mobiles.

Don't worry though I've got some new plans brewing

I certainly hope so
.
.
.

Smack talking aside, there are 30 Instant Start Infineon controllers in the sky somewhere over China, there are 1,000 4110's coming off the line in Mexico, and Bob is tirelessly slaving away on a hall sensor board for our 3220's.

I am hoping to turn you guys around from the dark side of sensorless-ness to the digital beauty of sensored RC motors.

Matt - I want to see one of those endless wheelies you are always telling me about. I will settle for 60 seconds of pure wheelie-ness.

-methods

 

[j3tch1u]

this is getting interesting

 

[deecanio]

I have a question, with the throttleboard limiter being on the fly, and i think Richard said 5a at minimum setting? if my packs 50v but my setting is 5a doesn't that mean i'm running a 250w system? (uk limit) that would make me "legal" no?

this country stinks D I think its 250w on a tandam and only 200w on a normal bike

Wow, we (I) have a 10kw limit.

Matt

Massively lucky there Matt, the UK sucks for electric limits, mostly because they (gov) dont want anyone having a reasonable alternative to Petrol, and being as they get 80p in the pound tax on the stinky earth killing gas why would they?
Gwhy, i think you are correct but my understanding is that 250w 15mph is the EU limit and being an EU citizen i demand my rights dammit :wink:
to put things in perspective then - the UK has a 200w limit and 15mph, however your not breaking the law to pedal at 40mph
One thing i do find really annoying is the pathetic 15mph limit, when it comes to cars 70mph is the limit on UK roads but the avaerage family saloon is capable of 100mph+ ?? however i dont see any law capping petrol vehicles to 70mph?
I find this sooooo frustrating that i'm totally prepared to flick the gov the bird (finger) and plough on with my 4kw 40mph baby, foook you, you expense claiming idle fooks


Cheers,


D

 

[gwhy!]

I find this sooooo frustrating that i'm totally prepared to flick the gov the bird (finger) and plough on with my 4kw 40mph baby, foook you, you expense claiming idle fooks


Cheers,


D

Im with you on that one D

 

[recumpence]

Gary,

The motor sprocket is 14 tooth and the jackshaft #25 sprocket is 60 tooth (if I remember correctly).

Methods,

I had a wicked wheelie (a couple of them) yesterday. I am not very comfortable with the power wheelies as of yet, so I only get a good one every once in a while. Wheelying this thing is like ballancing a stick on your finger. If it is too short, it is too twitchy to control easily. I could run all the way through the gears on the rear wheel of my 125s. But this thing is freakin twitchy. Occasioally I get a good 2 or 3 inch front tire off the pavement long distance power wheelie that I can carry from about 5 to maybe 25mph before I lose it. But, that is only one in many that I try. Anyway, it is fun.

Methods and Gary are right about the sensor thing. I am 100% ready to move to the sensored side when the bits get all sorted out. I am not an electronics expert. I am a mechanical guy. So, I am doing what I can to see how far I can push the mechanical side of things, while I leave them alone to work out the electron flow.

What I cannot believe is the reliability of this thing. I mean, other than a couple loose set screws, it just runs and runs. In fact, the motors only get luke warm and the ESCs barely show any temperature increase above ambient. That is what I like. I did not want something powerful that broke every other time I rode it. I had a modded dirtbike like that. What a freakin pain. I like to just go out and ride with too much power and no worries.

So far so good on that front.

Bear in mind, we are (in my opinion) nearing the edge of bicycle torque handling before parts begin breaking. This is part of my reasoning for running 20 inch wheels. I wanted to reduce the torque on the bicycle parts as much as I possibly could. I think our E-bike power systems can go far higher than what I am seeing. But, my concern is the bicycle components handling the torque. For the highest power setups, the absolute best bicycle components MUST be used. I cannot stress this enough! I mean, geeze, I am getting seriously concerned about popping spokes. That being said, we will never know untill we push to that point! That is what I LOVE about R&D.

Matt

 

[rizzlo34]

Does anyone have any experience with these?

-Ryan

 

[deecanio]

Hi Ryan,

see "freewheel crank resources" thread.

http://endless-sphere.com/forums/viewtopic.php?f=28&t=7641&start=255


Cheers,

D

 

[liveforphysics]

Methy- Your efforts in helping us get some great controllers at great prices and supplying FETs to enable these high power builds to be possible is fantastic. You are helping to make this hobby possible for so many people. However, my builds will always crush yours


Deecanino- Your police have no possible way to measure your power output. If you are going faster than 15mph, then make sure your legs are moving. They can't prove if it was the motor helping you or if you were just pedaling. F'em.

Matt- It's outstanding that your design has been so solid that you haven't had any reliability issues. That speaks a lot for your natural talent to engineer great parts. The bike looks, sounds, and accelerates fantastic! Great work!


My next build is going to be for on-road only. 20" or even 16" drive wheel. Very low COG. It's going to have no suspension, a light steel frame that I build myself, and a 6.5" diameter 50kw induction motor.

I want to see 3-4 second 0-60mph times, and no less than 100mph top speed.

This will be a bicycle, NOT a motorcycle. Pedals, lightweight, bicycle appearance.

 

[GGoodrum]

Does anyone have any experience with these?

-Ryan

Ryan --

Those are the same basic high-end ENO freewheel, that many of us have been using, either as part of the drive, or in the crank, or both. It is just in a more convenient form factor. We've been using the 23T ENO because it has slots, in the same BCD, I think, as the hole pattern for this unit.

I forget now who it is that is selling this item. Can you post a link? I actually need one.

-- Gary

 

[Miles]

http://sickbikeparts.com/catalog/product_info.php?cPath=21&products_id=62

 

[GGoodrum]

Matt --

One thing that might be interesting for those working on single 3210 setups would be if you disconnected one motor, and just ran with the one, to see what kind of performance might be expected. I think it is still likely to go like a bat-out-of-hell, but maybe slightly less wheelie-prone?

 

[recumpence]

With one motor it would be probably about 2/3 as quick, but with a HUGE amount of motor heat and ESC abuse. The ESC will kick out about 130 amps or so. The motor will not put out more than 6kw without serious objection (according to Bob at Astro). But, I have a surplus of power anyway. So, my guess would be it would look nearly as quick on the video, but require alot more throttle by the rider to accellerate hard and that at the expense of some serious abuse of the one ESC and motor being run.

Matt