Tamiya 801X - TamiyaUSA.com

PERFORMANCE TEST
My first RC was a Tamiya Hornet.
Okay it wasn’t nitro, but it was a buggy.
TAMIYA
THE X FACTOR
801X
GAS
words: James Revilla | photos: Carl Hyndman
W
hen we first got word of Tamiya’s entry into the 1/8-scale field, it was via a
truggy. After seeing the 801XT in person, one of the obvious the first questions
we asked was “so when is the buggy coming out?” I won’t elaborate on
the rest of that then-secret conversation, but the end result is right here:
Tamiya’s new 801X 1/8-scale nitro buggy. With this buggy, Tamiya jumped right into the
game, bringing along some of the unique features found in the truggy variant, and with the
same goal of crossing the line with as many checkered flags as possible.
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AUGUST 2009 | 73
GAS
PART #: 84067
STREET PRICE: $620
Price as tested: $1,785
setup time: 9 hours
experience level: Intermediate to Advanced
TAMIYA
801X
SCALE POWER
TYPE
DRIVE
GAS
GAS
X
1
0
8
A
Y
I
TAM
Thick Towers: The 801X’s front and rear
shock towers are a beefy 5 mm. thick, yet
milled for lightness without sacrificing durability.
Tank It: The fuel tank is a standard
and race-legal 125 cc. size, with a builtin overflow drain and splash guard.
01
Straight Liner: Both
driveshafts run a parallel line
from center diff to the front
and rear bulkheads for more
driveline efficiency.
key feature of the 801X
layout is how the center
driveshafts run parallel to
each other from front to rear. Since
this moves the engine mounting
position more to the side, they
compensated by angling the engine
at 15 degrees to bring the weight
back toward the center of the chassis,
effectively enhancing the chassis
balance and CG (center of gravity).
“When TRF goes racing, you can
expect a top-level machine—and the
801X lives up to that expectation.”
02
THE RINGER
• Inside the
bulkheads fore
and aft you’ll
find sealed, heavy-duty gear
differentials. Both bevel
gear differentials feature
hard-coated ring and pinion
gears. The input ends of the
diff housings are reinforced
with thick metal rings. Both
front and rear assemblies
are interchangeable for less
spare parts requirements.
Tune In Tokyo: Radio box
is semi-sealed with easy-access
hatches. Tamiya gives you the
option of using a standard Rx hump
pack or a flat 5-cell pack positioned
on the chassis next to the servos.
LAYOUT:
Kickup chassis, molded bracing
thickness:
3mm
material:
7075 anodized aluminum
SUSPENSION
TYPE:
4-Wheel Independent
turnbuckles:
Yes, steel
STEERING:
Dual bellcrank, center aluminum link
SWAYBARS (F/R): Yellow / Yellow
SHOCKS
15mm anodized aluminum
bodies:
damping (F/R): #400 / #400
pistons (F/R):
Y1 (6-hole) / Y1 (6-hole)
springs (F/R):
Red / Yellow-black
drive train
type:
4WD center shaft
differential:
3 (sealed bevel gear)
diff fluid (f/c/r): #5000 / #5000 / #5000
axle type:
Universal-type
transmission: Single speed
03
03
CHASSIS
Then again, it wasn’t really that hard to guess.
Read issue 158; I called it the right name.
02
01
GANGSTA LEAN • A
VEHICLE INFO
SIMPLIFIED
• First seen on
Tamiya’s 801XT
Truggy, the
turnbuckle brake system is
one of those “so-easy-that-noone-else-figured-it-out-before”
type things. No more fiddling
with set screws and thumb
wheels; if you want to alter
front to rear brake bias, it
is as easy as adjusting
a turnbuckle.
spur gear
Material:
Hard-coated steel
Clutch type:
3-shoe, aluminum
BEARINGS:
Metal-shielded
gearing
clutchbell/
spur:
14/48
GEAR RATIOS:
PRIMARY:
3.42:1
INTERNAL:
3.7:1
FINAL:
11.34:1
body, tires & wheels
body:
Tamiya 801X
tires (F/R):
Not included
diameter/
width:
N/A
hex size:
17mm
wheels:
Not included
dimensions
Big Damper: Large 15 mm. aluminum
shock bodies dominate all four corners.
Threaded shock bodies allow for quick tuning.
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weight:
7 lbs., 5 oz. (3,316g)
track
width (F/R):
12.08 in. (307mm)
wheelbase:
12.71 in. (323mm)
ride height
1.37 in. (35mm)
AUGUST 2009 | 75
PERFORMANCE TEST
TAMIYA
Testing
I see people driving their real cars and leaning like they had an 801X engine.
Unfortunately for me, it was a nice yet hot day in Southern California at the
time of testing. Revelation Raceway in Montclair, California, is our go-to
spot to test 1/8-scale vehicles, and this was the same place I had previously
tested the 801XT Truggy. Temperatures were in the 80s (although it felt a
lot hotter than that) but the track had a nice technical layout and the 801X
was ready to go.
Acceleration and Speed • If an
engine felt fast in a truggy, you can bet that it’ll
feel faster in a buggy. Due to the similar layouts
and powerplants, the 801X felt excellent in the
acceleration and speed departments. It took off
from the starting line at a high rate of controlled
yet powerful acceleration. Top speed was ample
for the track layout, and mid-range trigger work
was responsive.
Rating: 9/10
Braking •Running the same gear as the
801XT, the 801X features Tamiya all-star David
Jun’s trick brake linkage setup; if you’re not aware,
the design simplifies the brake linkages. Only
one rod connects the brake servo to the brake
assembly, and brake bias is as easy as turning a
turnbuckle rod. Identical dual drilled disc brakes
and lined brake pads had zero difficulty bringing
the buggy to a stop. I did not encounter any
brake fade throughout my day of testing. The
brakes on the 801 lineup are great, and I won’t
be surprised if other companies in the near future
start copying it.
Rating: 10
Low-Speed Handling • Low-speed
handling was on the spot. The 801X felt equally
nimble left and right, most likely a positive
byproduct of getting as much of the engine’s
weight as close to the center as possible. The rear
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end stayed planted down during low-speed
maneuvering, and the steering ratio felt
just right as I could easily steer the buggy
through tight and shallow corners with
precision. If I gave the buggy too much
initial throttle exiting a turn, the buggy had
a slight push. The suspension setup out of
the box felt a tad soft, so I wasn’t surprised
here, but better to have a slight push than
to have no rear traction at all.
Rating: 9
High-Speed Handling • With the
kit settings, some buggies have a little bit of
push (understeer) at higher speeds. For some,
this is a godsend that ensures the buggy won’t
loop out with too much throttle. Others might
wish for a little more front-end grip. Having a
combination of both is ideal, and the 801X
has it. The rear end kept its traction on
full-throttle, high-speed pulls—and yet during
corner entries I still had ample steering to get
the buggy pointed in the right direction. Even
with the high-output engine, high speed driving
didn’t feel like I was skating on the edge like
some other, less-capable vehicles.
Rating: 9.5
Rough-Track Handling • With the
same basic suspension setup as the 801XT,
I expected the buggy to perform well on the
rougher areas of the track. The large 15mm
shocks absorbed a majority of the punishment
that I gave it, and the kit swaybars
helped keep the chassis level
with the driving surface.
When I finished
building the buggy (but
before test driving it) I
felt that the suspension
seemed slightly soft as
a whole. However,
801X
GAS
GAS
test GEAR
radio:
Airtronics M11 DSS,
751572, $300
receiver:
Airtronics 92724,
included with radio
Steering
servo:
Airtronics 94771, $100
throttle
servo:
Airtronics 94773, $120
engine:
Trinity EB Mods Tuned
Ex-Tech.21, TRI40064, $430
Receiver
pack:
Trinity 1500mAh
hump pack, TRI20507, $24
fuel:
O’Donnell 30% quart,
#ODOP3330, $10
Exhaust
Pipe:
Trinity 2057 Ex-Tech pipe,
TRI40065, $113
Tires (F/R):
Pro-Line Crime Fighter
Premounts, 9014-31, $34/pair
CONTACT
Tamiya america:
www.tamiyausa.com
airtronics:
www.airtronics.net
O’Donnell racing:
(dist. by great planes)
www.odonnellracing.com
Pro-Line racing:
www.prolineracing.com
trinity:
www.teamtrinity.com
the suspension was still responsive on the dirt.
It didn’t give me a vague or slushy feeling on
the track. The 801X stayed flat over the uneven
bumps, and made it easy to plan ahead for
the next corner.
Rating: 9
Jumping • Most 1/8-scale buggies are good
jumpers, especially those targeted for the
competitive crowd. The 801X is no
exception, as Tamiya’s buggy
was great at leaving and
returning to Mother Earth.
After only a couple of test
laps, I felt confident enough
to attack the jumps as if
Worlds was on the line.
Controlling the buggy in
PERFORMANCE TEST
mid-air felt like second nature; it wasn’t slow to
respond to trigger movements, nor was it twitchy
or over-responsive. The 801X was consistent
jump after jump, regardless of jump angle or size.
Rating: 9
Wrenching
I prefer a slight recline myself.
Maintenance • As with a majority of
good race-spec buggies out there, hex hardware
is used throughout the chassis. The hinge pins
use locknuts instead of E-clips, and with the
exception of the engine mount screws, you only
need 2mm and 25mm wrenches to make a
majority of your adjustments. The trick-angled
multi-piece engine mount can be extracted from
the main chassis without disturbing the clutchbell
mesh. In the event that you need to get to the
front and rear differentials, be prepared for some
pit time as the main diff cases are sandwiched
between bulkhead parts, just like on the 801XT.
Rating: 8
Wear and Tear • I’m not exactly sure why
manufacturers make pointless front “bumpers”
on cars where the front wheels stick out farther
than the nose, but I do understand rubber shock
shaft boots and rear splash shields. The 801X
has them, and they help keep wear and tear to
a minimum. The diff cases are sealed, as is the
radio box. Molded side guards keep crap from
reaching the center diff and driveshafts. During
testing I didn’t notice any premature wear on
any of the components. The beefy front and
rear hubs/hub carriers took a lot of punishment
thanks to my often-sideways jump landings and
my tendency to grab too much throttle, but that’s
a personal problem that the 801X handled like a
$1,000-an-hour doctor would.
Rating: 9
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TAMIYA
Tuning • You can’t refer to a buggy as
“competition level” unless it has the standard
complement of adjustments found in its
contemporaries. The 801X has the usuals
(camber, caster, toe) and it also includes
extra tuning blocks, hinge pin inserts, and
shock pistons in the box. Multiple shock
mounting holes and threaded shock bodies
allow for fine-tuning. The same goes for
the front and rear hub carriers, which also
have multiple mounting points. Large
hex turnbuckles make camber and toe
adjustments easy. Finally, as mentioned
before, brake adjustment is a singleoperation job. If it weren’t for the diffs
not being as easy to access compared to
some of its peers, I would have given
the 801X a 10 in this category.
Rating: 9
Conclusion
It was a little weird that Tamiya went
opposite the norm by going with a truggy
first, followed by a buggy, but in this case
the buggy builds on the company’s quest to
become a player in the 1/8-scale world. The
801X shares many high marks with its larger
brother, including the amount of excellent
design features and suspension refinement.
When TRF goes racing, you can expect a
top-level machine—and the 801X lives up
to that expectation. On-track performance
is excellent, and without a doubt the 801X
can easily compete with the elite in the
very-saturated and very competitive
1/8-scale buggy class.
801X
GAS
SCORECARD
SCALE RATING: 1=POOR 10=EXCELLENT
9
10
9
9
9.5
8
INSTRUCTIONS
parts quality/fit
durability
tunability
overall performance
value
hits
• Excellent handling at all speeds
• Predictable in the air
• Brake linkage is trick design
misses
• Diff access takes some work
• Questionable (but hopeful) survival in a saturated class
main competition
Associated RC8, Losi 8IGHT 2.0, Mugen Seiki MBX6,
Hot Bodies D8, XRAY XB808
who it’s for
Competitive 1/8-scale buggy drivers looking to rock some TRF
GAS
TAMIYA
SCALE POWER
801X
TYPE
DRIVE
GAS
GAS
POWERPLANT INFO
T
he Trinity Ex-Tech .21 engine is one of our more reliable in-house mills, and since I used
it in Tamiya’s 801XT Truggy, I decided to run the same powerplant in the 801X buggy. In a
lighter chassis, the Ex-Tech stretched its legs and gave me almost instantaneous power. It was
a little hot out during testing but the Ex-Tech measured in at a steady 215 degrees, with a nice
clean idle and a broad powerband, unmatched only by its willingness to give me more go
then I actually needed (I turned my throttle high-point down to 80 percent since I had so much
power on tap!) This just states the differences that a true tuned engine can bring to the track.
engine data
x-dyno
data
POWER PLANT DYNO PERFORMANCE
Trinity Ex-Tech EB Mods .21 Race
Prepped
BORE AND STROKE:
0.643 in. x 0.656 in.
(16.22mm x 16.8mm)
Displacement:
0.21 in.3 (3.49cc)
FUEL:
30%, 12% oil
Pipe:
Ex-Tech 2057
plug:
TRI40110
peak x-dyno hp*:
1.38 @ 24,750 rpm
peak x-dyno TQ*:
56.99 oz.-in. @ 23,750 rpm
peak x-dyno rpm:
40,500
average HP:
0.93
average TQ:
37.86 oz.-in.
POWER FACTOR
LOW END (TQ/HP):
0.77 / 41.85
TOP END (TQ/HP):
1.08 / 34.12
correction factor:
1.078
*All numbers are SAE corrected
Needle settings
Power Factor: Our new rating is an average HP/TQ reading for two selected rpm ranges. Low-end power factor will be the
average values from 10,000-25,000, and the top end power factor will be from 25,000 to 40,000 rpm.
High:
Flush
LOW:
½-turn in from flush
mid:
NA
operating temp:
190-230° F
performance INFO
acceleration
curve
0-60 ft: 1.57 sec. @ 38.2 mph
Top Speed: 46.27 mph @ 163 ft.
Average Run Time: 8 minutes
test conditions
weather:
Hot, sunny
Temp/humidity:
84° F/50%
Barometric
pressure:
29.98 in.
altitude:
652 ft.
track type:
Hard, semi-packed dirt
handling
TURNING RADIUS:
4 ft., 2.1 in.
On power:
Slight understeer
off power:
Neutral
braking
Control:
Poor Satisfactory Good Excellent
Fade:
Poor Slight None
Overall:
Poor Satisfactory Good Excellent
AUGUST 2009 | 83
All of Tamiya’s high-end vehicles come with blue nuts.
ENGINE: