RazorBack Pro Skeleton Kit


Available on backorder

SKU: 10002 Category:


It all began when the C4/Rody
I’d been waiting for a half a year arrived…I didn’t have the heart to modify
it into a pullstart.

Out of the desire to not modify a
motor a project truck was born. It was to be a pan chassis, bump start
lightweight racetruck…an Unlimited Monster Truck.

Codename: Rody

First to test gearing
ideas, a truggy was used. This quickly revealed the shortcomings of truggies,
but gave me the information I needed to make early decisions on the

Then came our first
prototype truck. Many of you have seen the pics floating around. This was
another used to test concepts. The first VBS, gearing that no one had seen, but
still using as many off the shelf parts as possible. We tested this truck for a
year fine tuning what we wanted in a Racetruck.

From there, a clean sheet
all new truck was designed. Single axis transmission, center differential, two
speed, F&R brakes with a single backbone running the full length of the truck
for strength. The backbone tying into monoblock differential bulkheads with both
advanced geometry and
incredible strength (and that’s how the VBS made production.)

The deck started life off
as a 5/8" thick 4.5 lb slab of 7075 Aluminum and when we finish is only 200
grams losing more than 90% of it’s original mass. The backbone ties front to
rear VBS with a single spine interlocked into the chassis for the ultimate in
strength and rigidity. We wanted more aggressive suspension geometry as well as
a more raceable suspension so we tweaked the RacerX a little. The RacerX-II
Suspension, Victory Bulkless System, Ø8mm CVDS, and more projects were also born
out of these desires.

The first Prototype
Razorbacks (V3.0) debuted in Connecticut at the Monster Madness race in June of
last year. These were finalized at the track and in fact one was built there. 
These prototypes did superbly in the event. A dozen of these were made and we
enlisted the help of testers all over the United States to help us test these.

After a year of testing
we’d learned all we could from V3.x trucks and it was time to take everything
we’ve learned over the last 3 years of this project and make a production truck.

That brings us to today.

The Generation 4 Razorback
is ready to be made.

What is it?

  • A low center of gravity
    Monster Racetruck
  • Aggressive suspension
  • Single axis, center
    differential, two speed. Unheard of in the RC world.
  • Superior Strength
    and durability
  • Lightweight

which leads us to…

Generation 4 Razorback

  • Chassis & structure:
    • Pan Style, Bumpstart
    • Full Length with
      interlocking backbone
    • 10° front kickup
    • Titanium front skid and
      rear wear plate
    • Carbon Fiber component
    • Molded side skirts, seals
      up to the body
    • Integrated transponder
  • Transmission
    • Single Axis
    • Ø10mm one-way!
    • Center 8 Spyder
      Differential,  Quick change bias tunable with silicone fluids
    • Transmission comes out
      with just 4 screws for spur changes! 30 sec and you’ve got it in your hands.
    • Two Speed. Hardened steel
      spurs, lightweight plastic available too.
    • Wide range of gearing
      options, even able to change the splits on the two-speed
    • Independent front and
      rear brakes, quad carbon fiber brake disks with six calipers
  • Differentials
    • Victory Bulkless
      System – Towered Generation 4.4
    • 8 Spyder 7.5
  • Suspension
    • RacerX Suspension
      (Razorback Version)
    • SuperShocks (4 pack
      with 8 springs)
    • Generation 4 Servo
      Saver (Razorback Version)
    • Hardened Steel M6
  • Driveshafts
    • Ø8mm hardened steel
    • Hardened Steel
      dogbone type center shafts
  • Roomy battery box (K3)
  • The ever popular Ofna
    fuel tank.
  • 4 shoe clutch
  • 8x16x5 Bearings used
    throughout the truck for strength and ease of maintenance
  • Titanium front turnbuckle
  • Strobe limiters

The foundation of the Razorback is single rigid deck.
Starting off life as a 5lb billet of 5/8" thick material, we release the 7 ounce
beast within. The Razorback is one solid piece from nose to tail


Since the VBS was developed
for the Razorback, we of course have that, the trick was uniting the front, rear
and deck into a single unit. The backbone is a single spine interlocking the VBS
and the chassis deck into a single rigid assembly capable of withstanding
tremendous abuse.


The transmission is a
unique single axis center differential with a two speed. A wide range of
spurs & pinions are available, as well as changeable splits (difference between
1st gear’s ratio & 2nd’s.)

There power module is made
up of the carbon fiber component tray, the component mounts and the
receiver/battery box. It is
easily removable making cleaning & service a snap. No wires need be
disconnected, you don’t have to get into the receiver, just a few screws and the
whole assembly comes right out.

Though if you wish to just
remove the transmission, a mere 4 screws and it pops right out for quick spur
changes. Notice how well the sideshields cover vulnerable components. They also
do a terrific job of keeping the dirt out.

Though if you wish to just
remove the transmission, a mere 4 screws and it pops right out for quick spur
changes. Notice how well the sideshields cover vulnerable components. They also
do a terrific job of keeping the dirt out.


There is more detail, unfortunately MS orifice corrupted the file and this is
as far as I got on reconstruction.

More soon…..



Q: How much does it

A: V3 Razorbacks weighed
in between 9 and 9.5 lbs ready to start. I hesitate to quote V4 until we make
them since so much has been changed. I think it will be lighter.

Q: What else do I

A: The truck is very
complete, in addition to the Razorback Pro kit, you will need

  • Electronics: Servos,
    receivers, batteries, transmitter.

  • Power: Motor, pipe,

  • Body, Tires, Wheels.

Q: I have a hybrid
Maxx now and would like to make it a Razorback, is this possible?

A: The answer to this is
No, and Yes. No, that’s not the first kit out the door. Yes, we will produce
such a kit in the future.

Q: What will be
included in the kits?

A: subtract above list
from a truck

Q: When will they be
available and how much will they cost?

A: TBA/See answer below.

Q: What’s different
about these ‘Razorback Version’ kits of current production items?

A: Kits that have been
optimized in some way to work better with the Razorback.

Q: Will other
configurations & versions of the Razorback be available?

Of course be
several versions of the Razorback. This is the first of them and what will be
considered the elite of the kits – The Pro Model.  A complete truck.

On the horizon are kits:

  • Sportsman version: It
    will use towerless VBS, WideTrac suspension, perhaps a single speed,
    non-center differential, all for less money.
  • LiteRace model, Lots
    of Titanium & other lightened parts for the guys who run small blocks
  • Chassis & Transmission
    only kit. This for those of you who already have the bulk of these parts.
  • Conversion kit: A
    design exists for a chassis kit which will accept non-VBS bulkheads (stock
    maxx compatible type)

on delivery and prices

So the big question I’m sure you
are asking is: ‘how much and when?’

That is the question of the hour
isn’t it?

I’ve finished the design.

We’ve taken a guess at how long
it’ll take to make and how much it’ll cost.

But these are guesses at best.

There’s too many new parts here to
get really accurate answers.


Detailing out the known parts in
the kit and guessing at the Razorback structure and transmission I arrive at a
guesstimated list price of ~$2250 for a complete Razorback Pro Truck. Not as
good as I hoped, not as bad as some feared.


We believe that we could produce
50 of these kits for sale in 60 days, but we won’t do much else.


In order to do this we would have
to pre-sell them, that or take longer to produce them. If we do this as a full
truck, I think that with the 2/3s that’s known cost we will break even on this
run. This does not include past R&D, just cost to setup and make this run.

Some of you are sitting there
doing the math, and you’ve come up with a pretty big number on the gross sale

I agree, and if we accept the fact
that the there’s likely to be zero profit on this run that’s why we need to do
this as pre-payment, my pockets just aren’t deep enough to do this all at once.


Here’s my proposal, if we pre-sell
the bulk of this first run (say 90%), we will do our very best to make them in
60 days…at the pre-paid price of $1800 per truck.


What’s the difference between
‘pre-order’ and ‘pre-paid’? In a pre-order, you say you want it, but don’t pay
for it until it ships. With pre-paid, you pay for it now.


This will be a Limited Edition run
of 50 trucks. Each one serialized and signed. #s 14-64 are up for grabs.
Sequence in the order payment arrives.

We cannot do this on credit cards.
They will not allow us to charge that long before we ship. It’s checks or money
orders only (wire ok too.)



Q: What about International?

A: If you will pay all shipping
costs (regardless of reason), yes, you can buy them.


Q: Any guarantee they will be done
in 60 days?

A: None, though you can bet we’ll
do our very best.


Q: Can I use my credit card in the
UE store?

A: No, merchant account terms
won’t allow it. TOS at the CC co will not allow a charge that far in front of
the ship date.

Q: If I decide to get on-board
with this how will I pay for it?

A: Money Orders, Wire transfer and
I’ll make an exception and take Checks for this as well.


Q: When will you make the
commitment to allocate resources and set the 60 day goal?

A: If I get the impression that
enough of you are on-board with this plan I’ll do so right away.

Q: What if you get the impression
that everyone is on-board, but in reality not many take the plunge.

A: That certainly is a problem. In
such a case I may have to push the schedule out.  What I think I’ll do is set a
date of 2 weeks from when we say go on this. I will hold all payments until then
(not cash them.) At that time, we’ll tally up the sold kits, if it’s enough
we’ll continue to dedicate all our resources to the 60 day goal. If it’s not,
we’ll have to have a discussion on the topic, return, wait, etc.


Q: What if I pay and later change
my mind and want my money back?

A: That’s a tough one, obvious
reason I’m doing this is because I’m going to need to spend the money you pay to
produce the truck.

15% cancellation fee OK? and I
have two weeks to return the rest?


Q: Can I buy just the razorback
portion for my existing truck?

A: Not under this proposed plan. I
am taking a wild guess at what we can produce these parts for in production.
First run always goes over budget by 200-400%. That means I need the margins in
the other 2/3s of the truck to absorb the losses on the new 1/3rd. If we sell
50x of the whole truck, 2/3s of which have known costs, I think we will break
even on this first production run. Chances are that if I price & sell the
chassis & transmission for what I think we can do in production it will probably
cost me twice as much to make as you paid for it. And that just doesn’t work,
our pockets aren’t that deep. I believe that these first 50 need to go as
complete Razorback Pros or we have to await such a time that we have more
accurate numbers (after a production run) and can afford to bankroll such a


Q: Do the UE Trade-up and
Competitive Upgrade programs apply?

A: If you want to trade your
complete SM for a Razor w/ $1350 OR your complete ‘other’ truck for a Razor with
$1575…yes, I’ll accept that.

You may remove motor, electronics,
body and tires. It should arrive clean – no pigs.


Q: $1800 is more than I have right
now, but probably could have in 2 months, is there anyway I can get in on this

A: For those of you who find this
a tough nut to swallow all at one time, we’ll also do a 50% deposit on a $2000
price per truck.


Q: Doesn’t seem quite fair that
those who get in early in the 60 days pay the same as those who get in at the
last minute.

A: OK…

–In July, price for full
pre-payment is $1800 and $2000 for those who opt for the 50% deposit.

–In August, price for full
pre-payment is $2000 and $2100 for those who opt for the 50% deposit.

Is that fair?


I value your input on this and
hope you understand why we need to structure it this way.

This actually isn’t all that
foreign to us, we used to do this all the time with

but it’s not allowed with a normal merchant account
Now the question is do you have the faith….?


Here’s a
link to
the Limited Edition Pre-Purchase PDF form that you need to fill out and send in
with your order.

Edition Razorback Pro Pre-Purchase Pricing

1. 100%
in July $1800
2. 100% in August $2000
3. 50% in July $1000+ $1000 on delivery = $2000
4. 50% in August $1050+$1050 on delivery = $2100



1. Place
an order on the site. This Sales Order will get your name and contact info into
the database. I’ll actually ship from here.
2. Print the Pre-Purchase form and fill it out.
3. Include payment for the amount on the Sales Order.
4. Mail it.
5. Stay tuned to the forums for the latest information.


If you have more
questions (and no doubt you will) there are several good threads going on in the
forums on this topic right now. Of course there is always
e-mail as well.


Additional information

Weight 1 oz
Dimensions 1 × 1 × 1 in

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