After some play riding in Glamis and testing in the Arizona desert, the Moose thumb throttle is working well and is fairly easy to push.  The longer lever takes some getting used to since it places the idle position a lot further back.

The thumb lever was binding against the brake lever dust boot on the 400.  It needs to be a little further out on the handle bars so they don’t touch.  I had to trim the gripto get the thumb throttle body where it needed to be.

The throttle stop screw on the side of the thumb throttle walked in on both units and made it impossible to give the bike any gas.  Loctite fixed that.

I also had to go back to oem style throttle cables.  The ones that come with the Motion Pro twist kit are too long.

Details can be found at arizonaoffroadpromotions.com  The schedule is also on our race schedule page.

This series is a mix of motocross, desert and pavement with short laps on a time limit.

The guys at Racers Edge will be installing a new counter shaft and shift rod in the case along with a new crank, rod, piston and valves.

I’ll be heading down to their shop next week to put the bike back together so they can tune it.  In the meantime, I have to install a new rear sprocket (It was about to go too) and I’m going to swap the Motion Pro Twist Throttle for a Moose Thumb Throttle.  I just don’t have enough control with the twist throttle.

There should be plenty of time to get it all back together before the Thunder Rock Ranch race on May 12.  If not, the trx400ex is ready to go too.

This time I will be not be removing the handle bars or plastics.  I am also installing a Pro Armor kill switch at the same time.  Both projects require the fuel tank to be removed.  I will document the kill switch details in another post.

1 Remove the old grips

Whoever installed the grips on these bars used just a touch of glue, so they were easy to remove and very easy to clean up.  I used a pair of wire cutters to clip the ends of the grips open, then tore them back like a candy wrapper.
The Pro Taper handle bars have a diamond pattern cut in the ends to hold the grips better, so they don’t need as much glue.

2 Remove the fuel tank

There are 2 bolts and 2 straps that hold on the fuel tank.  There are also 2 bolts holding the front plastic to the fuel tank.

• Remove the seat
• Reach over the air filter, towards the carburetor and release the straps from the frame.

• Remove the 2 bolts on each side holding the plastic to the tank.
• Pull the plastic away from the tank far enough to fit a wrench in between and remove the bolts that hold the gas tank to the frame.
• Turn the fuel valve to the Off position.
• Remove the fuel line from the carburetor.
• Lift the gas tank up off the bike.

3 Remove the thumb throttle

• Remove the 2 screws from the bottom of the thumb throttle assembly on the handle bars.  Let the cable and assembly hang over the hood.
• Remove the plastic cover from the side of the carb.  There is one Phillips screw near the top of the cover, then lift and pull it out.
• Detach the end of the cable from the lever.  You can pull down on the cable to create slack, then slide the ball out of the lever.
• Loosen the lock nut at the top of the carb where it threads in and unscrew the cable end from the carburetor.
• Guide the throttle cable out through the front of the quad.

4 Install the Motion Pro Twist Throttle Kit

• Guide the throttle cable back through the quad, reversing the way the original one came out.
• Thread the cable in to the top of the carb and attach the end to the throttle lever.
• Back the threads out until there are a couple rows showing inside the carburetor and tighten the lock nut.
• Assemble the twist grip and the cable half of the twist throttle and slide them on to the handle bar.
• Insert the cable in to the housing and attach it to the twist grip. then screw the two halves of the housing together to tighten it to the bars.
• Twist the throttle all the way open and make sure it returns to closed without any binding.

There is a specific order that you have to follow to do it right,

1. Caster 6 degrees (make sure the frame is level or it won’t come out right)
2. Camber 1-1.5 degrees
3. Toe in 1/8″
4. Ride height will vary depending on your tires, but you want the front to be 1/4″-1/2″ higher than the back with the rider in full gear sitting neutral on the quad.

This setup will work good on any TRX450 w/arms

One more note:  The tie rod end mounts over the top of the steering stem and the bottom of the spindle.

I read about swapping 450R shocks on a 400EX in several articles on the Internet.  They all said you have to grind the shocks, but none really described how to do it.  After holding the shocks in place, I could see that it would be much better to grind a little off the upper shock mount than the actual shock body itself.

After grinding the mount, the top of the shock body still hit where the nut is welded in for the body mount. (Inside the shock  mount tab)  If you really don’t want to grind on your shocks, you could cut off the bolt and tack weld the body mount right to the top of the shock tab, but I chose to grind the shock.  It was just a tiny shave off the surface to make it fit.  If you put the top of the shock in the mounting tab and wiggle it around, trying to line up the bolt hole, you will scratch the surface of the shock enough to figure out where to grind.

With the stock front compression settings at he first notch, the front of the frame measured 12 1/2 inches from the ground.  After swapping in the 450R shocks, the same spot measures 13 inches.  The a-arms are at the bottom of their travel with no rider.  the compression on the 450R schocks is all the way at the top (no extra compression)

Here is a picture of the stock 400EX front shocks before the work.  The frame height here is 12 1/2 inches

Here’s a shot of the 400ex stock front shock on the right side.

The 400ex shock is at the top of this picture.  You can see the 450r shock is a little bit longer.  When you take off the stock shocks, the a-arms drop a little.  When you put the 450r’s in, they use up all the space.

This is the upper shock mount before any grinding.  The shock hits the rear part of the mount at the lower curve.

Here is the upper mount after grinding away enough material so the shock fit without hitting the inner part.  The bolt hole still wouldn’t line up.  The top of the shock needs to be ground just a tiny bit.

In this picture you can see the small spot that needed to be ground off.  You could also try grinding the nut inside of the shock mount, but since it was such a small amount, I chose to do it this way.

You can see the 450R shock mounted in the 400x tabs in this picture.

This is the final product.  With the 450R  shocks mounted, the front end sits half an inch higher than stock.  The suspension feels much firmer on compression and the rebound is smooth.  Gone is the bounce of the stock 400 shocks.  After riding around the yard, the front end feels way more stable, and it doesn’t lean as much turning.  The real test will be in the sandy whoops at the river bed later this week.

It will be interesting to see how the 450R handles, I still haven’t had time to take it out.

The only thing I plan on doing before the next race (besides general maintenance) is converting the thumb throttle to a twist and adding a kill switch.

The 450R had these parts when I bought it:

• Lonestar DC4 +2.5, +1 A-arms
• Lonestar Swing Arm, +1.5
• Axcaliber Axle
• Lonestar Anti Fade Lock Nut
• Lonestar Billet Rear Caliper Mount Kit
• Lonestar E-Brake Block Off Plate
• Elke Stage 4 Front Shocks
• AC Pro Nerf Bars
• PRM Bumpers
• Anti Vibration Steering Stem
• Pro Taper Handle Bars
• ESR Intake
• DASA Racing Full Exhaust
• 2002 CRF 450 Cam
• Stainless Braided Brake Lines
• K&N Cone Filter
• Aftermarket Hood

Some of the changes I plan on making in the future:

• Pro Armor Full Chassis Armor
• Pro Armor Swing Arm Guard
• Motion Pro Twist Throttle Kit
• Pro Armor Tether Kill Switch
• Fasst Flexx Handlebars
• ITP or Maxxis Wheels/Tires
• Clarke 3.9 Gallon Fuel Tank
• CV4 Hose Kit
• LED Lights
• Dynatek FS Programmable Ignition

This is going to be the new race bike.

Depending on the condition they are in, I’ll either try them out for one race or rebuild them right away.

Our old centrifugal juicer just wasn’t cutting it anymore.  We juice 2 meals a day and the entry level units aren’t made to handle that much use for very long.

When the Omega arrives we are going to do a side by side comparison to see how much more juice the 8006 produces, and the difference in pulp.