Tom's BEAST

lostrack

100 W
Joined
Nov 12, 2011
Messages
224
Location
London, UK
Yo!

First build. Am trying to build something really fun to ride...

After deciding non hub is for me (weight distribution, smaller controller, lower (safer) voltage & I actually like the sound they make) I got in touch with Matt Shumaker and ordered some kit.

Spec:


  • Giant DH Comp with Fox 40s and Hayes 8" strokers and Magura Gustav M rear. 8" travel front and back. New 450lb Spring.
    12S3P Turnigy Lipo (courtesy of Jozztek) @ 50.4V
    Shumaker DaVinci / Astro 3220 motor (courtesy of Matt Shumaker)
    Castle Creations HV160 (rev 2)
    Custom carbon fibre enclosure (courtesy of MOS furniture)
    Hyperion 1420i, 1KW Variable Voltage / Amperage PSU
    Cycle Analyst, Magura throttle, temperature gauges etc.
    Custom built drivetrain using BMX freewheels, Surly tensioners, custom springs, frame mounts...etc.
    Custom designed laser cut chainring with keeper plates (thanks BobC)

Thanks to: Matt Shumaker, Steve Labib, bobC, Matt Idontwanttopedal and EVERYONE who has helped with suggestions and support on this build.

View attachment 11
Naked bike.

The bike today


beastbox.jpg
beast-with-box.jpg
beast-top-view.jpg

My friend building the battery box mould out of mdf veneer offcuts. He actually used walnut veneer...!
bandsaw.jpg
It's so much easier with great kit and a very skilled cabinet maker (http://www.mosfurniture.co.uk

Priorities for this build -
Strong, good looking, tarmac shredding acceleration, great brakes, range of around 15 miles without trying to economise, room to expand. Burnouts a plus!


NEW PICS

IMG_1425.jpg

IMG_1423.jpg

View attachment 6

Video rendering just now...check after the break. THIS IS SO MUCH FUN (when it's working!!)

batts800.jpg

side view800.jpg

business end800.jpg Business End

dash800.jpg 250 amps. This happened when trying NOT to fall off the back (Brakes VS Motor)


There are a few cables/bits of tape still around, but I am so sick of building - I just want to get out and ride now. It's been almost 5 months of evenings and weekends, time for some reward:)

cheers

Tom
 

Attachments

  • beef800.jpg
    beef800.jpg
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*edit* - waiting for parts to arrive...took it for a trail session.

[youtube]lOJP9ITO0mg[/youtube]

Unpowered, this bike just shrugs off everything. Awesome. Can't wait to get it up and running.

This was my first trip back to the trails in about 3 years...nuts how much it has grown.


SNOW VIDEO!!!

[youtube]BbRV_1kf2j0[/youtube]


Basically showing off controllability and acceleration. A few wheelie pops too...
[youtube]g42AJV8_iqc[/youtube]

*edit - new video in HD*

enjoy
 
Beautiful battery box! Do make sure that you have enough room for the necessary wiring.

Where will you be installing the Matt Shumaker/Astro 3220 assembly? Considering that the triangle is already used by the battery box.
 
You're gonna like it...
 
Yes, remember to include space for the wiring its often bulkier than you expect it to be!
 
Hey Tom,

It looks awesome!

I cannoth wait to see it come together. Your box should be to you any day now. Please comtact me with any questions.

I will be in contact with you.

Matt
 
Probably where I would put it, below the down tube. Nice to see another go through the process of making a mold. Add a 1/4 to 1/2 inch on each side for wiring. Do you have access to a vacuum?

Nice choice of components, looking forward to the Nuvinci/astro combo. I will be putting one on a cyclone, but didn't really consider it for trail use. Would be really interested in how this works out for you. 80t seems pretty big, is this for the reduction stage? Trying to picture where you plan to put it?
 
Hi all,

Thanks for the replies. Fabricated an Alu copy of the wood battery box today, will unveil at some point tomorrow. :D

Have deliberately oversized the specs of batteries for expansion and cables...13mm+ hopefully this will be enough!

The motor will mount on the downtube, just have to work out if Matt's clamps will take up too much space on the inside of the frame. May have to use jubilee clips.

The 80 tooth adapter is to get a 10:1 ratio. Some calculations earlier mean the theoretical max speed @ 50.4v will be around 54mph. Call it an optimistic 50 with drivetrain losses and wind resistance...maybe 45.

My carbon fibre accomplice has some cold set epoxy - I will detail the process with lots of photos when it happens. Will involve rounding the edges with a router, and vacuum forming the lot.


Can't wait for the drive to arrive!

Happy Christmas all

T
 
StudEbiker said:
80T 130BCD (and many others) can be found here: http://www.ihpva.org/Projects/Sprocket/sp60_80.jpg

Cheers Stud! I forwarded this jpg to a CNC tech a few days ago and he said he needed a DXF :cry:. I wonder if there are any conversion programs?
 
Got one of these for Christmas...expect some HD video soon!

GoPro-Hero-HD.jpg


best

Tom
 
Today:

Drive has arrived!

What an absolute stunner. I will get the SLR out tomorrow and take some gorgeous pictures. Matt's work is of such a high standard, I am stoked.

The Astro motors are much smaller than I had expected too. Nuts they can put out so much power.

Big shopping day -

  • ENO 16T
    attachment.php

    52T Chainring (temporary)
    Full Face Lid
    Urge%20Down%20O%20Matic%20Veggie.jpg

    2x HEAVY non mtb chains,
    2x SURLY chain tensioners
    media.nl

    castle link adapter
    100A shunt

Big to-do list. Grinding down disc brake adapter, work out the optimum drivetrain chain line (not easy on this bike). Pics soon.

Tomorrow: Down at the workshop with mr Jozztek tomorrow to plug it all in..!

T
 
awesome.
Looking forward to the vids and completed bike.

D
 
Latest machining tasks -
IMG_0528.jpg

IMG_0524.jpg
On the way now to get some disc spacers and chainring spacers.

IMG_0526.jpg
Bike

IMG_0527.jpg
Closeup of Matt's work.
IMG_0528.jpg

A major note also - spent almost the whole day with Steve aka JOZZTEKhttp://www.jozztek.com/shop/ yesterday who went way beyond the call of duty to help me set up the electronics. Got the motor turning!

He sells Turnigy packs in the UK at a good rate, and tests each cell for 2 months (!) before they are sold, so it's much better to buy from here rather than HK imports. Plus, he's a top bloke.

Went for a spin in the 300KW Mazda sports EV ... still grinning! Next build...car?
 
I like your video hitting the jumps. I am trying to get my skills up to jump some gaps on a dirt jumping bicycle.
It takes a pair when you are old like me.

Anyways, I don't understand what you are doing with Matts' setup. How is the freewheel sprocket going to drive
the bike?
 
motomoto said:
Anyways, I don't understand what you are doing with Matts' setup. How is the freewheel sprocket going to drive
the bike?
A second sprocket behind the disc on the left side of the wheel. It is a single ratio setup. With a 3220, this thing should rip!

Matt
 
Hi,
motomoto said:
How is the freewheel sprocket going to drive the bike?
recumpence said:
A second sprocket behind the disc on the left side of the wheel. It is a single ratio setup. With a 3220, this thing should rip!
That FW location, about 4"-6" above the pivot point, will exacerbate the chain length issues.
 
Yes, the drivetrain is the next challenge here.
Currently we are looking to run the chain straight (without lateral flex), and fold it over the swing arm (vertical flex). Unfortunately, the swing arm prohibits a straight line run - I will show a picture later.

The pulling side of the chain will have to have a slight bend in it. I will make a dual tunnelled nylon guide, based on the idlers in mx bikes. Secondly, a dynamic chain tensioner will take up the slack.

I'm interested to see if pulling all this power through it will cause the suspension to compress under acceleration?

Have taken some pics - will post later

This has been great fun so far and everyone is really interested in making creative contributions - exactly what I'd hoped for:)

Happy New Year!
 
motomoto said:
I like your video hitting the jumps. I am trying to get my skills up to jump some gaps on a dirt jumping bicycle.
It takes a pair when you are old like me.

Anyways, I don't understand what you are doing with Matts' setup. How is the freewheel sprocket going to drive
the bike?

Hehe, I do feel confident on these jumps - spent many years of my youth with my friends, a shovel and sunny weekends building them. It's much easier once it's your dirt!
Could have done with more speed on the last set, went for it and cased the front hard. I flipped, the bike just shrugged it off! Have since invested in a full facer.

Loved your build by the way. What's the latest?
 
Testing the electronics - [youtube]R8zx7VEC1Vc[/youtube]

Next - build drivetrain chainguide. I have a number of pics for this - it's not going to be easy...

It's going to be based on nylon non-rolling systems like motorbikes. Any suggestions?

Yes I know it will cause a little bit of drag. There is no way to get the chain line straight - and bending the chain up/down is much better than around objects.

photo.JPG
photo2.JPG


Thoughts?
 
I would use a roller there, a fixed style like on a dirtbike will shred in minutes of use, trust me I tried it. You have to remember on a dirtbike, the suspension is compressed most of the time and there is little chain actually dragging on those under load. In your case the harder you pull the chain the harder it drags on that slider. An idler is a much better plan but make ut strong ir it will bend or break!
 
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