Specialized Rockhopper Pro Cyclone Build

Fredorbea

100 mW
Joined
Jul 30, 2014
Messages
41
Location
Melbourne, Australia
This has been a long time in the making and is well under way now so i thought it was about time i shared something.
This is my first E bike build and i certainly bit off plenty.
I needed a bike capable of climbing steep hills for fairly long stints for my commute, so i settled on a Mid drive. I was keen on a
Lightning Rods kit but at that stage last year the waiting list was enormous and there was quite a few teething problems. Then
there was the AFT which is made locally for me but i am in manufacturing and had issues with how this kit was constructed for
the asking dollars. I liked the Kranked ego kits and this is probably where i drew most of my inspiration from.

So i ended up designing a kit based on a cyclone 48V motor and gearbox, then incorporated a standard flanged freewheel at the
motor output. Then i used the Kart chain reduction idea as the secondary reduction to solve the problem of the other cyclone based
kits, crazy cadence. This is what i came up with (go easy its my first one). :D

So the specs are:

Specialized 2011 Rockhopper Pro

ISIS Cranks

48v Cyclone motor and Gearbox

Lyen 12 FET 3077 controller

12s3p 15ah Lipo

Freddie designed and manufactured kit!

Cheers Fred
 

Attachments

  • Kit.jpg
    Kit.jpg
    36.6 KB · Views: 5,496
  • Kit 2.jpg
    Kit 2.jpg
    41.5 KB · Views: 5,495
  • Bike.jpg
    Bike.jpg
    48.7 KB · Views: 5,495
  • Kit installed.jpg
    Kit installed.jpg
    28.3 KB · Views: 5,495
  • 20150415_183350 upload.jpg
    20150415_183350 upload.jpg
    41.4 KB · Views: 5,496
  • 20150508_200005 upload.jpg
    20150508_200005 upload.jpg
    36.1 KB · Views: 5,496
Unfortunately i can't get access to the machines at work on the weekend as its closed :( otherwise it would have been finished
ages a go. I have done at least half of the gearbox housing, crank set mount, drive cover and drive shaft. The only part i haven't
started is my crazy heat sink, i have left it till last as i think it will be the most challenging to machine.
 
Damnit, lol
Aesthetically, it's a beautiful design!
If I had a critique, it's that it looks so strong that it looks heavy...at that thickness, you could probably lose quite a bit of material out of the centers of each face of that downtube bracket for weight savings...if it even matters to you.
Is your downtube squared?
Freewheeling cranks?
 
Yes free wheeling cranks and an extra bearing as part of the crank to offer some support for the free wheel.
The down tube is a strange shape of sort of rounded square so i left some clearance for hard rubber packing.
The side plates weigh bugger all as they are milled away on the inside(see pic), i did this to keep a clean look and
hopefully actually keep it clean! It was a delema at the time as they look pretty cool all milled away with the ribs.
 

Attachments

  • 20150323_205336 upload.jpg
    20150323_205336 upload.jpg
    29.2 KB · Views: 5,473
  • 20150313_185722 upload.jpg
    20150313_185722 upload.jpg
    25.3 KB · Views: 5,473
file.php


Really excellent work here. I designed something similar for myself last year but it never got off the CAD page. That sprocket must have been very difficult to manufacture. I designed my part to work with replaceable sprockets like the one in the picture. A plus is being able to change gearing ratios by changing the drive sprocket. Maybe something to think on. Good job!

H330140.jpg
 
Its my job to program and machine little parts like these so i have access to some unbelievable machines. It would have
been nice to have an easy ratio change like that, I was really cramped for space to fit motor, gearbox, bearing, free wheel
sprocket and another bearing in between the cranks. Thats a nice little sprocket though i will keep it in mind. cheers
 
Another part off the machine after work, not too many more to go. Its really starting to take shape now, very exciting :D
 

Attachments

  • 20150518_190836 upload.jpg
    20150518_190836 upload.jpg
    22.4 KB · Views: 5,348
Hi mate, awesome plans for the cyclone.
When you sort the cadence it will take your top speed down considerably, it would be a good mod for trials riding and steep climbing.
Darren
 
Super beefy! I dig it.

Fredorbea said:
The down tube is a strange shape of sort of rounded square so i left some clearance for hard rubber packing.

Yeah the (hydroformed?) shape is really weird to get right in CAD and the first thing I thought of when I started reading through the thread. I ended up using photometry with a known sized object and it still took a lot of 3d printed test parts to get right for a battery enclosure on my Specialized.
 
I put a photo of the frame into SW then scaled it using the known dimensions of
the axle centers. I didn't know how well this would work so I left some clearance
around the frame and it has pretty much exactly what I drew when I had made the parts.
This method seems to be actually very accurate if scaled well.
 
Ok big week this week with lots of parts being finished and even some onto the bike. I am still waiting to
get some time on the Macturn multitask machine to finish my elaborate gearbox, i sure know how to make things
hard. i can finish it in one operation on the Mac or i have to do it on the mill and it will take 5 separate operations :(

Here are some pics of the bits i finished this week, the crankset seems to work really well. I have put the derailleurs back on and
the shifters and a chain. It shifts through the 2 gears on the front as I rode up and down the street really well. Very happy.
Thanks to Boostjuice for the ideas on the crankset and for the tip of a Kevlar kart sprocket, which i think I'll paint.

I have a bit of an issue with the shifters hitting on the twist throttle, is there a common solution for this?
 

Attachments

  • 20150521_200054 upload.jpg
    20150521_200054 upload.jpg
    33 KB · Views: 5,085
  • 20150521_204355upload.jpg
    20150521_204355upload.jpg
    27.2 KB · Views: 5,085
  • 20150523_170935upload.jpg
    20150523_170935upload.jpg
    30.1 KB · Views: 5,085
  • 20150523_173459upload.jpg
    20150523_173459upload.jpg
    41.2 KB · Views: 5,085
  • 20150521_200159upload.jpg
    20150521_200159upload.jpg
    24.6 KB · Views: 5,085
Not much to report sorry. I have been on holidays and house renovations are keeping me from doing much. Boring! !
I will hopefully do some more this week.

Cheers
 
+1 = me too!

with the shifters hitting the throttle, some have had success changing to Microshift shifters as the levers are a bit smaller, or you could change the throttle from 1/2 twist to thumb style.
 
Things are finally seeing some progress! The new mount/gearbox has been finished (see pics) so i am free to assemble the rest of the drive. :D
Super excited to finally get the gearbox complete so it can turn a wheel. I will hopefully get the unit assmbled this weekend and will post some more info
then.
 

Attachments

  • 20150710_164733upload.jpg
    20150710_164733upload.jpg
    49.7 KB · Views: 4,311
  • 20150710_164750upload.jpg
    20150710_164750upload.jpg
    49.4 KB · Views: 4,311
  • 20150710_164802upload.jpg
    20150710_164802upload.jpg
    52.6 KB · Views: 4,311
I have had some test rides and was happy with how everything performed. As was my feeling I had the gearing a little
low so top speed was 45kph. Then i realised that i had an 11 tooth sprocket on the rear and it wasn't loving the speed runs
up and down the street as much as i was! :D I will change some of the gears around and maybe try making a 15 tooth sprocket
on the Kart reduction.
I then had to quickly strip it all down and clean everything because work had a big batch of stuff going to the anodizers. I was
able to slip my stuff in with them.
I got some white vinyl and cut my own stickers to bling everything up. I also did my Lyen controller while i was at it.
Just waiting on some new gear cables and brake rotors, then i will finish the wiring.
 

Attachments

  • 20150808_164950.jpg
    20150808_164950.jpg
    69.2 KB · Views: 4,286
I found this thread from researching the ego kit. Wish I had your machine skillz. I worked at a machine shop with million dollar machines probable like the ones you program and machine with. I'm not a machinest though. Great job your doing and looking forward to a video of you riding.
 
I found this thread from researching the ego kit

This is a nice custom build if you can do all the machining ?? , but If you want an off the shelf kit the EGO kit is an expensive piece of junk compared to the AFT 1680w EMAX, there was some people discussing the differences here:

https://endless-sphere.com/forums/viewtopic.php?f=28&t=59063
 
I have been testing the bike on and off over the last month and i have now fitted a throttle tamer to try and offer some more
ride ability. Thanks to Toby82 for selling me one he had, as they are now out of stock at Greyborg USA.
It was set at 40 amps at 48v and popped wheelies pretty much at will, cadence is nice at about 80 rpm and you can really help out if you feel inclined. :lol:

I have knee problems at the moment which is stopping me from riding much, but it looks as if i will need the electric assistance if i am going to ride much in the future. :cry:

I still haven't managed to make the heat sink but i haven't seen any hotter than 33 deg Celsius anyway. I think that's due to the motor happily in its comfort
zone due to the 80 rpm cadence.
Here is some photos of the pretty much finished bike and a pic of the dash i made which shows voltage and temp of the motor windings.
 

Attachments

  • 20150829_115903.jpg
    20150829_115903.jpg
    49 KB · Views: 3,914
  • 20150829_120036.jpg
    20150829_120036.jpg
    47.4 KB · Views: 3,914
Nice machining, i would imagine it would cost a bomb to get someones to machine that :p

How did you get such high reduction to the crank ? is that a cart sprocket and what reduction ratio did you use ? I have seen something similar boost juice used the dual freewheeling cranks and you have done something similar ?


cadence is nice at about 80 rpm and you can really help out if you feel inclined. :lol:

I can't see what the fascination with 80 crank RPM is, some normal peddle bike people prefer 100RPM long term, because if you limit to that max crank RPM with bike gear ratios to the back it means you severely limit the top speed as their is only such a small gear you can put at the back that won't wear too fast. Also on a high power motor that is 2-3000w even if you do add peddle power at full speed it will make little to no % difference to your speed with or without. If it was a low power 2-500w yes you will notice the difference... but 250w continuous human power vs 2000w peak motor power at top speed will make little or no difference to your speed if you peddle or not.. From a stop is when peddling makes the most difference and when its needed the most. And u can assist in both 80 or 130 crank rpm top speed regardless of the max crank RPM from the get go, But with the higher top crank RPM option you wont limit your top speed but also be able to add from the stop power and can put a larger gear on the back that doesn't wear out as quick.
 
Back
Top