400 SCRAMBLER/SPORT/TB -

Reed Spacer
Kit 400

THIS ITEM IS ON SALE!
$25.00!!

For Polaris 400 only. Increases horsepower and extends reed life. A must for big bores, to correct primary compression.

Race Porting

Designed for the 400 Polaris engine. This porting makes this engine the horsepower champ stock cylinder 400 Polaris ATV's. Tremendous power from a wide, hard hitting power band, and it's still dependable. Produces 73 to 75 horsepower at 7450 RPM with the proper additional parts. 70 plus horsepower in under 2 seconds on a warmed up engine. This baby lights fast!
Requirements: Race modifications

Trail Mod Porting

Designed for the 400 Polaris ATV. The trail mod cylinder porting is worth 8 more peak horsepower. Excellent all around performance.

Requirements:An HPD trail or race pipe, clutch kit and forged piston. 92 Octane fuel. Billet head (BHPG12) with girdle kit are recommended.

PART # TMC
• LIST $300.00

Fill out this form to send with mods

Bore Cylinder

Send us your cylinder, and we will bore, hone and chamfer the ports.

Fill out this form to send with mods

Remove .04" to .08" material
PART # BORE+
• LIST $75.00

Remove up to .04" material
PART # BORE
• LIST $65.00

Big Bore- Remove .1" or more
PART # BOREBB
• LIST $85.00

Trail Head Mod

Head machining designed for the 400 trail porting and 92 octance pump gas. Improved all around power with
trail porting.

PART # TMH
• LIST $70.00

Fill out this form to send with mods

Billet Head, Cover & O-Rings

A must have for the Polaris racers
and performance riders.
Our billet, 2 piece head, is a complete design, and not just a machined copy of the original stocker. It provides concentric water flow, thus preventing hot spots. Sealed to the cylinder with O-rings to create a metal to metal contact, providing even engine temperatures. The improved combustion chamber pocket and squish area, increases horsepower and torque. Additionally, the head allows girdling through the cylinder to the crankcase, providing a much stronger and durable package.
Girdle kit is optional.
Not for use on 416 PowerMAXX.

Trail Mod 400s
Designed for stock, piped or trail mod 400s on 92 octane fuel. Improved torque and horsepower.

Billet Head Girdle Kit

For Polaris 400 cyl. only (not for use on 416 POWER MAXX products).

For Polaris 400 cyl. only (not for use on 416 POWER MAXX products). Send in Cylinder to HPD for modification.

Fill out this form to send with mods

Replacement Chambers for Billet Heads

Often copied but never duplicated.

Flywheel Lightening

Flywheel not included ... send us your flywheel and HPD can dynamically spin balance your flywheel to .5 grams. Prices are for the labor to machine and balance your flywheel to race or trail specs.

400 Trail Lightening
Removes 1 pound and keep the electric start. Responds noticeably faster than stock.

PART # LF
• LIST: $105.00

400 Race Lightening
Removes electric start and lightens flywheel by 2.3 pound. Make engine rev extremely fast.

PART # LFR
• LIST $115.00

Fits all 400s and 250s with HPD Pipe.
Scramblers, Sports, and Trailblazers.

MSA Spark Arrestor Muffler

Weighs only 3 lbs. Muffler body is 3 inches in diameter and 12 inches long. This muffler is forestry approved, repackable, and is 93 DB. Aluminum construction only.

PART # MSA
• LIST $153.00

Fits all 400s and 250s with HPD Pipe.
Scramblers, Sports, and Trailblazers.

MTD Muffler

HPD’s Adjustable Clutch Weight Kits

We have found, what we believe are the best Adjustable Weights available. We are stocking 4 versions of these weight kits. Designed to get the power to the ground. They have a very aggressive curve for a faster up shift, and are adjustable in three areas, Low, Mid and Top End. The Low End is adjustable without removing the weight from the clutch.

60-76 Grams

PART #AWHH 60-76
• LIST $230.00

65-81 Grams

PART #AWHH 65-81
• LIST $230.00

55-71 Grams
PART #AWHH 55-71
• LIST $230.00

Aggressive Clutch Kits

Kit includes: Helix, weights, 2 springs, installation guide, and shims (if needed).
Aggressive clutch kits are faster accelerating, plus more mid range response. Back shift is improved at all speeds. These kits also improve belt life. All have been tested for accuracy on dynoed engines with on board computers. This is the best performing trail set up.

400 Sport/Scrambler
(Race)
Designed to be used with race ported motor and ATVRP8 pipe.

PART # CK4RM8
• LIST $190.00

400 Sport/Scrambler
(Trail)
With trail pipe and/or trail porting. Higher engagement than stock.

PART # ATVCK4MA
• LIST $190.00

400 Drag Race Mod
Designed to be used with race ported motor and ATVRP8 pipe.

PART # ATVCK4DR
• LIST $190.00

CLICK HERE FOR CLUTCH SPRINGS

CLICK HERE FOR CLUTCH WEIGHTS

Single Throttle Cable for Polaris -
Metal Throttle
Part # STC

Single Throttle Cable for Polaris -
Plastic Throttle
Part # STCP

Single Throttle Cable
(for metal throttle)
PART # STC
• LIST $35.00

Single Throttle Cable
(for plastic throttle)
PART # STCP
• LIST $35.00

WISECO
Forged Pistons

Due to past experience with broken pistons on modified ATVs, we require WISECO pistons be used on all modified engines, and recommend them for all others. Includes: Piston, rings, pin, and clips.

REQUIRES: Cylinder honing or boring.

These adjustable kits are industry leaders for providing smooth and precise upshift and backshift, which improves your efficiency, performance and durability. Tunable with custom cam angles and springs. Twin roller operating in enclosed helix track.

For Scrambler 400 94-02 EBS and Trail Blazer 400 EBS 2003
MUST STATE MODEL OF MACHINE AND MODIFICATIONS IN "COMMENTS" SECTION OF ORDER FORM.

PART #TAS03X
• LIST 369.00

Secondary Clutch Assembly ONLY

Same secondary clutch as above,
but just a secondary clutch assembly

Team Secondary Clutch Springs

Secondary springs control shift rate.
Fine-tune your secondary clutch with TEAM springs manufactured to the most exacting specifications.
Spring Height at 2.4" - 1.4"

Black/Red
120-185 Wt
PART # 210090
• LIST $24.95

TAS03X Team Secondary Clutch Springs
Chart 1
Load Heights at 2.05" + 1.05"

Secondary springs control shift rate.
Fine-tune your secondary clutch with TEAM springs manufactured to the most exacting specifications.

Bright Green/Purple
105-185 Wt
PART #210314-001
• LIST $24.95

TAS03X Team Secondary Clutch Springs
Chart 2
Load Height at 2.0" - 1.0"


Secondary springs control shift rate.
Fine-tune your secondary clutch with TEAM springs manufactured to the most exacting specifications.

Green / White
105-185 Wt
PART # 210215
• LIST $24.95

Team Helix's

EBS and NON-EBS Helix's

400 Head Gasket

PART # 3084731
• LIST $31.48

Super Duty Clutch Buttons

This kit makes your secondary buttons almost indestructible. Used on our super sport racers for 10 years without breakage.

PART # SSBK
• LIST $65.00

PART # SSB
• LIST $3.00 each

Starter Eliminator Kits

Kits includes: Cover plate, gasket, and 3 nylock nuts.

400 Oil Injection Eliminator
PART # OIEK
• LIST $27.00

Performance
Reed Valves

HPD 400 & 416
V-FORCE Delta II

The dyno proves gains throughout the power band. Improved throttle response and acceleration. These performance reed valves use exclusive custom reed material and stops.

Reed Spacer
Kit 400

THIS ITEM IS ON SALE!
$25.00!!

For Polaris 400 only. Increases horsepower and extends reed life. A must for big bores, to correct primary compression.

Steering Post Bearing

If your steering is loose, this is the product for you. This lower steering post bearing is made of 6061T6 aluminum, has a 660 high impact cast bronze bearing with grease grooves, and is held in place with 1/4 inch allen bolts with nylock nuts. Fits all models with 7/8" steering post.

PART # SPB
• LIST $35.00

Adjustable
Steering Damper

Hydraulic steering damper for Polaris ATV's helps save your arms and thumbs on rough trails or tracks. The damper unit has a 7-position clicker adjustment. Fits all concentric drive models and Sportsman 500s. Available for 7/8" and 1" steering posts.

For 7/8" steering post

Part # ASD
•LIST $139.00

Handle Bar Clamps
FOR STOCK POSTS

Machined from 6061T6 aluminum. 2 piece clamps rigidly mount super cross or super bike bars. HPD logo engraved.

Clutch Pullers

PRIMARY CLUTCH PULLER:
This tool is used to remove the motor clutch from your Polaris ATV.

PART # 20-66
• LIST $35.00

Heavy Duty
Engine Mounts
80 Durometer
For Performance or Race Engines

Heavy Duty mounts should be used on performance machines to keep the engine in correct alignment, making the clutches more efficient and a faster ATV.

Mounts are sold each (not in sets)

NOTE: Mounts are sold each (not in sets). 250s and 400s require 3 mounts. (Not for use on 500s.)

ATVCT

Disc brake on transmission.
Mounts to frame.

Non-Concentric
Chain Tensioner

PART # ATVCT
• LIST $75.00

ATVCTC

Disc brake on rear axle.
Mounts to swingarm.

Concentric
Chain Tensioner

PART # ATVCTC
• LIST $75.00

Add safety to your ATV with a tether switch. anyone racing or riding aggressively should have one. Also a good safety idea for the beginner.

PART # TS
• LIST $30.00

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