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Hot Rod Mods - Pro Armor/Sparks Racing Honda 500R


Making a TRX450 into a better all-around trail & dune quad

2010.honda_.trx450r.front-left.black_.riding.on-sand.jpgHow good is the stock Honda TRX450R? Good enough to be a perrenial top choice for off-road racers and trail riders all across the country. But even good machine can always be made better, right?  As Bill Murray in Stripes would say, "That's a fact, Jack. " 

So, to prove this theory right, we took a 2007 model 450R, which we had access to, and set about transforming it from a 'standard' looking and 'standard' running TRX450 into a veritable roost-rocket, fully blinged out 500R dunster!

Transformers Begin!

To start off this transformation, we consulted with noted ATV racing engine expert, Curtis Sparks. Curtis has been in the business of making ATV motors excel, ever since his days as a Honda Factory backed three wheeled ATV racer. This way way back in the early eighties. After his Honda tenure, Curtis opened a shop in his hometown of Bakersfield, California, and from then to now has made a living by making all manner of four and two stroke engines out perform his competitors.2010.honda_.trx450r.front_.black_.riding.on-sand.large.jpg

Back then, all Curtis wanted was more horsepower and torque to get ahead of his fellow teammates. Today, he enjoys a reputation for building some of the best, most reliable engine kits in the business. No small feat, for sure.  

More than a few top factory racers have sought out Curtis's help in making their "factory" mounts even faster. All without sacrificing reliability. To tell the truth, that's exactly the combination we were looking for as well. 

How it all works

For starters, we opted to install one of Sparks Racings Big Block 101mm piston and cylinder kits on our TRX450R. These kits do not require any machining of the lower cases to accommodate a larger bore piston, and are the simplest, most reliable way to extract more power out of your Honda 450R. 

Cost-wise, you are looking at right over $1000 for the complete kit ($1099.95). You get everything you need to transform your Honda into a full 500cc machine. Curtis does recommend that you run only Racing fuel in your engine to get the maximum amount of power with these kits (more on this later). But having to shell out a few bucks more per gallon to get the full benefits of all this work seems to be a small sacrifice to pay for the return on your investment.

We did not stop there however. We also wanted Curtis's expertise on how to extract every last ounce of power and torque out of this larger displacement motor.  A Sparks Racing port job, ($550) took care of this for us, and Curtis's many years of grinding out extra power has proven the worth of these  extra porting tricks he is the master of.

We ran a standard Honda crank, with one of Sparks racing camshafts (torque grind-$234.95) to up the motor a notch higher in the horsepower/torque curve . A Sparks Racing Exhaust system, including header pipe ($499) was also added, as well as  a DynaTech Ignition with a custom ignition curve ($349).

Finally, to complete our motor modification, we had Sparks Racing redo our stock Honda carb  and had it bored from 40mm to 42mm ($325).  Now to handle the increased horsepower and torque the engine had, we installed a beefier clutch using one of  Hinson Racings clutch baskets,  and new clutch plates,  and springs ($375).2010.honda_.trx450r.front-right.black_.parked.on-sand.jpg

Turning and Burning

All that power, with no adjustment to the machines handling and suspension, wouldn't amount to much if you didn't also modify the stock suspension  and chassis on the Honda TRX.   

We put a set of Janssen Outlaw II A-arms up front, with  a 3/4" longer Janssen rear swingarm on the back. To further increase the machines stability, we  added a RRM +2 inch longer rear axle on the back.  This got our chassis tracking straighter in the rough, so it was now up to the increased speeds our 500R was capable of.  

Another plus with the Janssen A-arms, is that they have adjustments for caster and camber, and come with upper Heim joints. These units  sell for $999 and  come with a lifetime warranty against breakage. Our Janssen three quarter inch longer rear swingarm sells for $740 ( $899 with a new bearing carrier).

By installing a set of Elka Elite shocks on the front and back ends, we were able to maximize our wider Janssen A-arms and longer swingarm to full advantage.  While Elka shocks are not cheap (they sell for $1395 a set of fronts, and $1095 for the rear) we felt they gave our machine a much smoother, more controlled, ride than our standard fully beaten stock shocks could offer. Elka also offers a new rear linkage kit for the Honda TRX which sells for another $395.2010.honda_.trx450r.front_.black_.riding-wheelie.on-sand.jpg

Bling it to me!

When it comes to making a sandaholic comfortable, a certain amount of Bling is always necessary. Depending on your sandoholic temperment, the amount of Bling is usually proportional to the size of your pocketbook. In this case, our resident food critic, ethics enforcer, and all about dunatic, Chef Wally came to the rescue. 

Chef Wally, (as he's  happens to be known) was responsible for all the Bling and Zing on this particular machine. Chef's has a purists heart and touch, especially when it comes to customizing a four wheeler. His attention to detail on this machine, was typical for him.

In true Chef fashion, he removed almost every nut, bolt, washer, and anything he could pry off thequad and had it sanded, chromed, and powercoatedm and polished again. 

The final product, is an exquisite machine that stands as a testament to Blingology. It looks simply MARVELOUS.  Chef's buddy in Las Vegas, who specialize in helping him with his Bling Dings, is Ram Proline (702) 396 4500 who does all his powder coating.  Complements to the Chef, and don't spit in our food anymore, okay? 

Wheelmen & Tiresters

Since this machine would be seeing ,much sand duty, a set of OMF reinforced beadlock wheels, with scalloped, red anodized rings, were added to the mix. We picked these wheels because we know they can stand up to the mega air leaps, off bottomless dunes, this quad would surely be doing.

Again, these wheels are not on the cheap side, and will set you back around  $280 per wheel. The OMF rims were mounted to 21x7-10 GBC unidirectional Shark Fin front sand tires. These units carve a tight line in the sand, and help immensely with the machines steering in the dunes.   

On the back end, a set of 20x11-9 AMS Side Winders were mounted. These awesome sand tires fully complemented the increased traction and more precise steering of our sandsational Honda 500R. 2010.honda_.trx450r.close-up.handlebar-brakes.jpg

Odds and Ends

Fullbore Innovations is a Portland, Oregon based company that makes replacement plastic bodywork for ATVers and UTVers. They make some of the best looking, and longest lasting plastic out there. Therefore, we installed a set of their black pear-colored Honda TRX replacement plastic on our 500R. This gave our machine a hot, sexy new look, that jived with all the Bling Factorness our bud, Chef Wally, had invested in this mount.

Pro Armor has always had a reputation for building sano, well thought out products, including some of the best bumpers, grab bars and nerfs in the industry. We bolted on a set of their newest footpeg/heelguard/nerfs. These units are the trickest of the trick, and feature a huge, serrated footrest that insures your boots will always have traction, regardless of what terrain you happen to be driving through. The cost of the Pro Armor Powergrip pegs is $149.95, with the Sport nerfs selling for $197.95, and the Powergrip heelguards going for $169.95.  .  

We also put one of their Ram horn bumpers on the front, ($139.95) and one of their rear grab bars, as well as a full chassis skid plate.  All these products fit, finish and alignment were first rate. 

A set of red billet ASV F3 levers were mounted to the clutch and brake sides of the handlebars. These levers are crash proof, and feature a special pivot design that allows the lever to fold out of harms way in a crash.  They also feature adjustable reach perches that can be dialed in for small, medium or large hands, a  handy feature.2010.honda_.trx450r.rear-right.black_.riding-wheelie.on-sand.jpg

In the handlebar department, we put on a set of Fasst Flex handlebars, mounted to an  IMS/Roll steering stem. This combination helps to make for easier steering action, more leverage, and an extra bit of suspension, through the handlebars.

Chain Gang

One area you don't want to skimp on, especially when you have added power, is on the drivetrain.  To ensure we did not have any "power-to-the-ground" problems,  we put one of Sidewinder'Sprockets Lifetime Guarantee Ti chains and sprocket kits on our machine. These are among the best out there, for their increased durability, and their ability to handle major power increases. 

Other Cool Stuff

CV4 makes a host of multicolored hoses that you can mix and match with your ATVs overall color scheme.  They are also well made and designed to meet the grueling needs of professional NASCAR race crews, so you know these things will last. They also make an excellent heat shield duct tape that helps to dissipate heat from vital engine areas, such as the fuel tank, air-box, and exposed exhaust areas.

Another extremely sano product we installed on our Honda 500R was one of H.E.P.'s (815-842-2002) exhaust heat shields to our Sparks Racing pipe. It sells for $42.99.  It is an excellent way to keep heat build up from melting your boots or riding gear. They come in various color combo's, including red anodized, which is what we chose to mount to our machine. H.E.P. also makes a replacement rear fender mount that is sturdier than the stock Honda unit and helps keep the plastic attached to the rear of the machine. It sells for $59.95. 

2010.honda_.trx450r.close-up.left_.engine.jpg 2010.honda_.trx450r.close-up.rear_.jpg
2010.honda_.trx450r.close-up.right_.engine.jpg 2010.honda_.trx450r.close-up.left-a-arm.jpg

Final Solution?

When it came right down to it, we knew we had a winner on our hands, both for reliable performance, and outright good looks.  We spent several grueling weeks out testing it at one of our favorite dune ride areas. This was to confirm or deny our first impressions of the machines torquier, harder hitting nature, and to judge its overall reliability. We also wanted to get other riders opinions on the machines overall look and feel.

Everyone who rode it or saw it, came away impressed with the performance and Bling appeal of our total package, sandsational sport duner. The longer, wider chassis components, and Elka suspension certainly contributed to the overall good feel and fit of our newly modified Honda 500R. It was easy to ride, with a broad, distinctive, but effortless powerband. It ran like a bat out of Hades on the low-end, and hooked into a hard hitting mid-range, and easy shifting top end powerpull. 

There was no hint of a herky-jerky powerspread with this machine, only a throaty, responsive, torquey engine that was all about smoothness and hookup.2010.honda_.trx450r.close-up.muffler.jpg

After all of Curtis Sparks and Chef Wally's hard work, their never ending attention to detail, and  much blood, sweat, and the occasional tears, we now owned a rip-roaring, torque monster Honda 500R.  Nuff said.

Time it took to complete this project:

More months than you can imagine.

Costs associated with it:

Occasionally, approaching astronomical.




CURTIS SPARKS RACING: (661) 872-4343.

PRO ARMOR: (888) 312-7667


ELKA SUSPENSION: (450) 655-4855

FULLBORE PLASTICS: (503) 261-1418


OMF: (951) 354 8272

TM DESIGNWORKS: (541) 535-1612

CV4: (336) 472-2242


TRAIL TECH: (360) 687-4530

IMS/ROLL: (760) 731-5920

RAM PROLINE: (702) 396 4500


500cc Sparks Racing Big Block Kit-Includes 101 mm piston, rings, pin, cylinder, head and base gaskets, uses stock crank    $1,099.95
Sparks Racing torque porting    $550.00
Sparks Racing Exhaust system, including header pipe    $499.00
Camshaft-Sparks Racing torque    $234.95
Stock Honda carb bored from 40 mm to 42 mm    $325.00
DynaTech Ignition w/custom ignition curve    $349.00
Clutch-Hinson Racing basket, plates, springs    $375.00

Janssen Outlaw 2 long travel +3 A-arms w/Janssen custom ball joints, tie rods included     $995.00
Ram Proline Powdercoated candy trans red (top arms), rainbow trout pearl (bottom arms)    $350.00
Elka Elite series triple rate long travel front shocks,    $1395 per pair
Streamline Steel braided brake lines +3" with polished brake line holders (2 per side)    $88.95 (lines) $59.95 (polished clamps)
Trail Tech bullet headlights, 35 watt one spot one flood    $150.00
IMS/ROLL anti-vibe steering stem +3"    $ ?
Pro Armor MX Bullhorn front bumper    $89.95
Janssen Outlaw  three quarter inch longer swingarm    $740.00
Elka Elite rear shock    $1095 w/Elka linkage $395

Fasst Flex Handlebars    $299.95
ASV F3 lever set (holiday pack, red)    $179.95
Pro Armor Billet brake lever    $179.95
Pro Armor billet shift lever    $89.95
Pro Armor 3 piece nerf/heel/peg combo    $299.00
Powdercoated candy trans red paint for nerfs    $275.00

OMF 3 piece beadlocks red/black    $259.95 ea.
GBC Sand Shark front tires (21x7-10)    $ ?
AMS Side Winder rear V-shaped paddles (20x11-9)    $ ?

Sidewinder Ti-series chain & sprockets    $175.00
TM Designworks rear chain roller    $49.95

Fullbore Innovations Honda 450R full fender plastics  in black    $575.00
Fullbore custom nose piece black,    $125.00
Pro Armor rear grab bar    $119.95
Powdercoated candy trans red for grab bar    $85.00