Project LTZ - Turning Suzuki's Z400 into a pro caliber race winning entry
By George Davis

THE PRODUCTS

The Houser a-arms include these chrome-plated covers to keep mud from packing inside the bottom shock bolt hole. This is a prime example of the thoroughness of the Houser Racing design--built by racers for racers.

The transformation began with Houser Racing’s proven long-travel a-arms.  The +3 inch a-arms widen the LTZ out to the 50 inch MX width.  The a-arm design allows for the use of 19 3/8 inch shocks (stockers are around 16 inches) and brings suspension travel up to 11 inches!  The kit features specially designed long-travel ball joints.  The ball joints are sealed with durable rubber covers to keep dirt, sand and water out--increasing ball joint life.  The bottom ball joint even has a grease zerk fitting for easy lubrication.  The Houser a-arms also feature durable needle bearings instead of bushings, as well as grease zerk fittings for ease of maintenance.  The Houser a-arms come complete with chrome-plated tie-rods.  The complete kit sells for $950 with silvervein powdercoated a-arms.  For an extra $75, Houser will chrome-plate the upper a-arms for a trick look.  With the Houser kit you will re-use the stock tie-rod ends and a-arm to frame bolts and nuts.  

Houser also recommended installing one of their steering stems ($210 silvervein powdercoat or $270 chrome-plated).  Houser designed the steering stem to eliminate the dreaded bump-steer that the LTZ suffers from.  The stem is gusseted for strength and features an anti-vibration handlebar mount.  We also installed Houser Racing’s steering stem to frame mounting bracket ($85) and their dogbone-style handlebar steering stem clamp ($85).     

Houser Racing/Custom Axis LTZ long-travel rear suspension kit

Houser Racing recently completed development of a long-travel rear suspension system for the LTZ to compliment its front end package.  At the heart of the Houser kit is a completely re-designed shock linkage arm which allows for nearly 12 inches of suspension travel.  The re-designed linkage requires the use of a shock nearly 2 inches longer than the stocker.  A 1.25 inch longer swingarm stretches the Suzuki out a bit for improved traction and handling.  The swingarm is a round-housing style which eliminates the stock LTZ’s overly complex chain adjustment procedure.  The round housing design is very similar to that found on Honda’s 250R/400EX.  The kit comes complete with a billet aluminum, dual row axle bearing carrier that includes an external grease zerk fitting that allows you to grease the axle bearings without disassembling the entire rear end.  The increased suspension travel requires the airbox to be raised slightly.  Houser Racing supplies a well-crafted bracket which easily accomplishes the task.  The Houser kit is well thought out and very complete.  It includes all the brackets, bolts and such to complete installation. The kit sells for $995 with the swingarm finished in a durable silvervein powdercoat. Houser also makes a very durable rear chain guide ($55) which bolts right on and protects against DNFs due to chain derailment. 

Project LTZ controls-Before and After: Great effort was taken to cleanup the clutter on the handlebars. Special thanks to Mark Baldwin of Baldwin Motorsports for his assistance in sorting out the electrical system to accommodate the simplified starter button and Pro-Design tether kill switch.

Project LTZ underside-Before and After: Notice how the upgrades widened the Z out to MX legal 50" width. The +3 inch Houser Racing long-travel a-arms and Custom Axis shocks greatly improved the handling of our LTZ.

Houser Racing has cured the age old problem of keeping stickers looking new. But they aren't stickers at all! Houser's logo is actually embossed into the powdercoating itself!	Cycra graciously supplied us with their mobile pit stool. It's become the must have tool in the ATV Scene garage. Notice the numerous trays for keeping tools and parts organized and the cushioned seat!	ATV Scene resident mechanic Robin Eickleberry developed this carburetor choke knob which allows you to relocate the handlebar mounted choke to directly on the stock LTZ carb. The handlebar choke is an integral part of the light/on/off/start switch housing. You need to relocate the choke in order to remove the switch housing. Eicklebarry plans to offer this product for sale in the new ATV Scene store soon.

Custom Axis has partnered with Houser Racing to develop quality shocks for the Houser long-travel front and rear suspension packages.  The shocks are purchased directly through Houser Racing.  Over the past decade, Custom Axis has earned the reputation of building high quality, top-performing ATV racing shocks.  The shocks designed for the Houser kits are no exception.  These shocks have  3-4 inches of sag, thus helping to lower the LTZ’s high center of gravity.  The Axis shocks feature remote reservoirs, dual or triple rate springs and are fully compression and rebound adjustable.  The front Axis shocks sell for $1325/pair, while the special long-travel rear shock retails for $925. 

The Houser Racing steering stem and steering stem top clamp bolted on effortlessly. Houser recommended a +1 inch stem which felt very comfortable when combined with the Pro-Taper CR-High handlebars we selected for this project. The stem is available with either standard size handlebar or pro-taper type bar clamps.

All Houser powercoated components are clearcoated as well to insure a long-lasting, durable finish.  Houser Racing also offers package discounts when shocks and suspension kits are purchased together as a complete kit.  Savings range from $10 to $75 dollars depending on the particular package.  The Houser and Custom Axis products also feature detailed instruction manuals complete with color pictures and diagrams.  This is a refreshing change from past experiences.  The staff at ATV Scene has been modifying ATVs for racing for the past 15 years, and we’ve seen the majority of products shipped with little, if any, instructions.  There’s nothing more frustrating than spending thousands of dollars on go-fast parts only to spend countless hours scratching your head trying to figure out how to put the products together or how to dial them in.

Want more detailed product information on the Houser Racing/Custom Axis suspension upgrades?  Surf over to houser-racing.com.  The Houser Racing site is newly re-designed and features a plethora of information on the suspension systems.  Houser even has their detailed installation instructions available online. 

Now that we had are suspension upgraded to pro-level race specs, we needed some additional products to round out our chassis performance upgrade.  Team Industries supplied one of their stock to +3 inch width adjustable racing axles ($599).  Readers may not recognize the Team Industries name, but they have been building ATV axles since 1985.  Team is a top OEM axle supplier, manufacturing over 500,000 axles a year.  Team is also a major player in the snowmobile industry.  They recently launched an aftermarket ATV product line, featuring adjustable width axles for all popular sport quads.  The Team axle is manufactured from a special high-strength, heat-treated steel alloy and has a shiny, hard coat finish.  The axle comes complete with black anodized, forged aluminum sprocket and wheel hubs.  The fitment of the Team axle is top-knotch.  We installed it with zero difficulty.

We installed a 7-way adjustable steering stabilizer to help smooth out feedback to the handlebars.   Extended length a-arms and swingarms require longer brake lines, so we upgraded the LTZ with braided steel lines front and rear.

The Powermadd handguards come in a well-packaged kit including all mounting hardware and easy-to-follow, detailed installation instructions.

HiPer Technologies hooked us up with a complete set of their ultra light-weight carbon fiber beadlock wheels.  Wheel weight is known as unsprung weight.  Unsprung weight is the enemy of any suspension system.  Every pound saved translates directly into better suspension performance.  We went with 10x5 fronts (4-1 inset) and 9x9 (centered) rear sizes.  The 10 inch front rims have an outside beadlock and a inner re-inforcing ring that is actually molded into the wheel.  The 9 inch rears have inside and outside beadlocks virtually guarantying that your tire will stay in place.  The Hiper beadlocks sell for $183.75 each for 10 inch fronts and $199.50 each for the 9 inch rears with the dual beadlock.  The Hiper wheels are the lightest beadlock wheel on the market (weighing 5.8 lbs. For a dual beadlock) and have proven just as durable as their aluminum competition.

Project LTZ rear suspension-Before and After: The +1 ¼ inch Houser Racing swingarm with redesigned long-travel linkage, Custom Axis shocks and Team Industries +3 inch axle brought the LTZ up to pro-level race specs in the rear.

The Team Industries extended axle is a well-crafted piece. The package includes the trick, black anodized wheel and sprocket hubs and all the necessary hardware for installation.	The upper heim-style ball joints on the Houser Racing a-arms feature a molded rubber cover to keep out sand, dirt and water.	Hi-Per's carbon fiber wheels are the lightest beadlock racing wheel available. So light in fact that when the UPS delivery man handed us the box, we thought that either just the front or the rear rims must be inside. After tearing it open, we were amazed to find all four wheels inside!

We wrapped the Hiper wheels in a complete set of Kenda Klaw MX tires—20x6x10 fronts and 18x10.5x9 rears. The Kenda Klaw’s are the tire of choice for Team ATV Scene’s Kory Ellis. The "Klaws" perform well for Kory and did the same on our tricked-out Z.

Finally, we installed a set of PowerMadd’s Star series handguards ($34.95) to help protect our precious digits from moto roost.  The molded plastic handguards feature a fully adjustable aluminum mounting system to accommodate a wide variety of handlebar/controls/grip combinations.  

Dialing in your shocks OK, you've installed your new shocks, but your work isn't done. Today's shocks are adjustable so you can dial them in to perfectly suit your riding style and terrain. So load up your newly suspended ATV and head out to your favorite track or riding area for a couple of hours of testing and adjusting. Take your time and be sure to only change one setting at a time. Preload Preload is how stiff the spring is on the shock. At the top of the shock there are two nuts. The one at the bottom is the adjustment nut, while the one at the top is the jam-nut; it locks the adjustment nut in place. Tightening the adjustment nut will increase the preload, allowing for a stiffer ride. To provide a softer ride, back-off the adjustment nut up on the shock, thereby decreasing preload. Compression Damping Compression damping is the amount of force the shock will absorb. A harder compression setting should be used to soak up landings from massive jumps, while softer compression should be used while riding over less aggressive terrain. The compression adjustment is on the gas remote reservoirs just turn the knob to the softer or harder position. Most shocks today have an 8-position adjustment knob. Position 1 is the softest, while position 8 is the hardest. In the event there is no indicator, unscrewing the dial will allow a softer compression, while screwing the dial in will make for a harder compression setting. Rebound Rebound is how fast the shock returns to its original position after being compressed. For a riding area with lots of jumps or whoops in a row, a faster rebound should be used. A smooth riding area such as a TT track will allow the opposite. To adjust the rebound, look for an adjuster near the bottom of the shock. To adjust for a faster rebound simply unscrew the adjuster, to allow for a slower rebound, screw it in. Tender Spring Crossover The "tender spring" is the smaller, upper spring found on today's dual-rate shocks. The tender spring crossover height is the most significant handling change you can make using the shock's external adjustments. Increasing the tender spring crossover height makes the suspension stiffer. While decreasing it makes the suspension softer. The crossover height determines when the stiffer main spring takes over in the suspension range of motion. Remember, your suspension should bottom out at least once somehwere on the track to ensure that you are using all of the shock's available travel.

RIDE IMPRESSION

The comparison between the stock LTZ and our project quad can be summed up in three words: Night and Day!  Our project LTZ’s handling is 1000% improved over stock.  With it’s limited suspension travel, the stock LTZ easily bottoms out even on smaller jumps.  Plus the stock rear linkage “packs up” in the whoops.  The Houser/Axis suspension kits dramatically improve the quantity and quality of suspension travel.  This setup can handle any track obstacle.  No more teeth-clenched bottoming or packing up in the whoops.  Plus, the Houser/Axis setup lowers the Suzuki’s center of gravity, eliminating the “tipsiness” of the stocker.  Project LTZ handles and turns on par with the $30,000 custom quads of the top professional racers.

John Houser of Houser Racing is a licensed mechanical engineer and it shows in the professionalism of their products.  It’s difficult to appreciate how complex the engineering of a suspension system is.  However, realize this---Mr. Houser succeeded in building a better rear linkage suspension system than an entire team of Suzuki engineers was able to do.   Combine Houser’s expertise with top shock building mind of Mike Hallock at Custom Axis and you have a combination that is tough to beat.

The comparison between the stock LTZ and our project quad can be summed up in three words: Night and Day!

The Team axle has stood up to much abuse without bending or breaking.  It’s definitely durable.  Hiper’s carbon fiber wheels have also proven bullet-proof.  And unlike aluminum wheels which lose their new, polished look almost immediately, the Hiper wheels still look like new after many motos and washings.  The Kenda Klaw rear MX tires lived up to their reputation and performed great.

Baldwin Motorsports assisted us in fabricating this trick Tim Farr replica aluminum screen to replace the hole in the front fenders after the headlight is removed.	The Houser Racing swingarm is a round-housing type, which eliminates the poorly designed stock Suzuki chain adjustment procedure. Also, notices the billet aluminum brake caliper mounting bracket which is included in the Houser kit.	For this stage of Project LTZ, we kept engine mods at the bolt-on level. Baldwin Motorsports provided a complete stainless-steel exhaust system and ProDesign Pro-Flow air filter/intake to breathe life into the engine. Look for an evaluation of the Baldwin Motorsports' Tim Farr replica 450 engine kit soon.
The Houser Racing bearing carrier that is supplied with the long-travel rear end kit features a zerk grease fitting that can be reached without removing the carrier from the swingarm. Now you have no excuse not to keep the axle bearing greased!	Here's a good look at the Houser Racing rear shock linkage. It is totally redesigned from stock-allowing for 12 inches of suspension travel. It's important to note that the Houser linkage DOES NOT hang down any lower than the stock Suzuki linkage, thus not decreasing critical ground clearance.	The fit and finish of the Houser Racing swingarm is top-knotch. The stock Suzuki front chain guide bolted on the the swingarm perfectly. The Houser Racing rear chain guide is built to stand up to abuse.

Are we impressed? Definitely.  So impressed in fact that we no longer pass by the LTZ to ride the new YFZ.  We have transformed the LTZ’s suspension into that of a top pro-level racer.  Now we need to breathe some much needed life into the engine.  With the installation of a 450 big-bore kit and FCR carburetor, we predict that our LTZ should be ready to challenge even the most highly modified YFZ or TRX!  Stay tuned to see if this is the case.       

Contacts
1-877-6-GOFAST houser-racing.com	877-GO-HIPER hiper-technology.com
209-368-5046 customaxisshocks.com	218-847-9582 team-ind.com
powermadd.com	kendausa.com