Jeff Fredette can make any generation KDX go faster than anyone else in the world. Don't believe us? Well, it's been proven every year since the first KDX 200 was introduced in 1983. From the time he threw his leg over his first KDX, Jeff has produced a list of off-road racing accomplishments that is without compare.

Becoming the world's most recognized and accomplished KDXpert was no simple task. It meant the loyalty, commitment, and dedication to transform this undersized trail bike into a competitive off-road racing machine. Because of this ongoing love affair, Jeff has decided that he should share his knowledge and experience with all his fellow KDX riders. So whether you're competing with Jeff at the races or simply against your buddies on the local trails, Fredette Racing Products is the place to go for all your KDX performance parts, services, and tips.

Fredette Racing Products has a lot to offer each and every KDX rider. Our catalogs are full of products that have helped keep Jeff and his many customers at the front of the pack. We also keep a large selection of OEM and used parts for your KDX. Simply tell us what it is you need, and we'll reply within 24 hours with the price and availability. If you want your KDX to be the very best, it can be. We offer both engine and suspension shop services. These can be viewed on the engine tips page.

Long live the KDX!

Engine Tips

There are a number of engine performance products and services available for all KDX models which I have tried and would recommend. Because everyone operates on a different performance need and budget, I have decided to list my recommendations in the most logical and economical sequence.

1989-1994 "E" Models: The first modification I would recommend is to replace the stock exhaust pipe and silencer with an FMF pipe and a Powercore 2 or TurbineCore 2 silencer. While both silencers will perform comparably, the Powercore 2 model is designed for closed courses and the TurbineCore 2 "spark arrestor" model is required at all government regulated riding areas. At the same time I would recommend replacing the stock jetting with a 45-48 pilot jet, a 152-158 main jet, and a 1173 needle set in the middle position with the air screw adjusted out .5-1 turns. These simple and fairly inexpensive modifications will noticeably improve the performance of your KDX throughout the power band.

If you still want more power from your KDX, I would recommend that you send us your cylinder so we can work our magic on its ports. This modification will provide even greater performance throughout the power band with more revs on top. After making this modification, I would recommend replacing the stock jetting with a 45-48 pilot jet, a 152-158 main jet, and a 1173 needle set in the middle position with the air screw adjusted out 5-1 turns.

Still want more low-end throttle response and performance through the power band? Then I recommend replacing the stock reed valve with a Boyesen RAD Valve. If it's more bottom end performance you want I would recommend installing an FRP torque ring. This small device will boost bottom end performance at the expense of only a couple hundred RPMs from the top. No additional jetting changes are required with either of these modifications.

1995-2006 "H" Models: The first modification I would recommend is to replace the stock exhaust pipe and silencer with an FMF pipe and silencer. There are two pipes available. I recommend the Gnarly Rev pipe for the more experienced rider and all other riders riding in fast terrain with good traction. This pipe will improve performance throughout the power band with the most noticeable hit in the mid-range and up.

I recommend the Gnarly Torque pipe for the less experienced rider or riders on more technical terrain, because it also improves performance throughout the power band, but with a more manageable power delivery. The torque pipe is not recommended for the 220s. There are also two silencers available. While both silencers will perform comparably, the Powercore 2 model is designed for closed courses while the TurbineCore 2 spark arrestor model is required at all government regulated riding areas. No jetting changes are required with this modification. These simple and fairly inexpensive modifications will noticeably improve the performance of your KDX throughout the power band.

If you still want more power from your KDX, I would recommend that you send us your cylinder so we can work our magic on its ports. This modification will provide even greater performance throughout the power band with more revs at the top. After making this modification you may need to replace the stock jetting with a 45-48 pilot jet and a 155-160 main jet. For 220 models only: you can improve low end throttle response and add even more top end performance to this model by letting us work a little extra magic on your cylinder head and carburetor. Just send these components with your cylinder and we will turn your 220 into a machine that even your 250 buddies will admire!

Still want more low-end throttle response and performance throughout the power band? Then I recommend replacing the stock reed valve with a Boyesen RAD Valve. If it's more bottom end performance you want, I would recommend installing an FRP torque ring. This small device will boost bottom end performance at the expense of only a couple hundred RPMs from the top. No additional jetting changes are required with either of these modifications.

Suspension Tips

Suspension is one of the more difficult components to recommend, because so many variables exist. Which is why I ask that you please keep in mind that the following recommendations should be used as a guideline only. Individual rider ability and the type of terrain could move you up or down a spring rate if your weight is on the border of any of these specified weight ranges.

Forks

1989-1992 "E" Models: I have found that the stock forks work pretty well for most riders less than 140 lbs. For riders that weigh between 140-170 lbs, I recommend replacing the stock springs with a .33 kg spring. For riders weighting between 170-210 lbs, a .35 kg spring works well, and a .38 kg spring works for riders weighing over 210 lbs. I recommend setting the clickers between 6-12 clicks out for each of these weight categories.

1993-1994 "E" Models: I recommend replacing the stock springs with a .38 kg spring for all riders weighing 150-200 lbs, and .40 kg spring for all riders weighing 200 lbs and up. Clickers for all weights should be set between 6-10 clicks out.

1995-2006 "H" Models: I have found that the stock forks work fairly well for most riders that weigh less than 140 lbs. I recommend replacing the stock springs with a .38 kg spring for riders that weigh between 140-190 lbs. For riders weighting between 190-220 lbs a .40 kg spring works well, and .42 kg springs work for riders weighing 200-250 lbs. For riders over 250 lbs, or if you are not sure of the spring that is right for you, please contact us. For each of these weight categories I recommend setting the clickers between 8-14 clicks out.

By following these recommendations I am confident that you will notice significantly improved performance from your forks. For 1993-2002 models only: You can improve the performance of your forks even more by sending them to us, so we can replace the stock valves with Race Tech Gold valves.

Shocks

1989-1994 "E" Models: The stock spring seems to work well for riders between 150-200 lbs. For riders weighing over 200 lbs, I would recommend replacing the stock spring with a 4.8 kg spring and set the sag at 3.75-4".

The type of terrain you are riding will determine the correct compression and rebound settings. I recommend setting the compression adjuster (located at the top of shock) at about 6 clicks out for faster terrain and 12 clicks out for the slower, more technical terrain. The rebound adjuster (located at the bottom of the shock) should be set from 8 clicks out for faster terrain up to 14 clicks for the more technical stuff.

1995-2006 "H" Models: The stock spring seems to work well for riders that weigh between 180-210 lbs. I recommend replacing the stock spring with a 4.6 kg spring for riders weighing less than 150 lbs, a 4.8 kg spring for riders weighing between 150-180 lbs, a 5.2 kg spring for riders weighing 210-240 lbs, and a 5.4 kg spring for rider more than 240 lbs.

The type of terrain you are riding will determine the correct compression and rebound settings. I recommend setting both the compression adjuster (located at the top of the shock) and the rebound adjuster (located at the bottom of the shock) at about 8 clicks out for faster terrain. For slower, more technical terrain I recommend setting both the compression and rebound settings at about 12 clicks out.

By following these recommendations, I am confident that you will notice significantly improved performance from your shock. If you're looking for maximum shock performance, however, I would strongly recommend that you send us your shock so we can re-valve it. I would also recommend that you let us service your shock every 800-1000 miles, to prevent premature failure.

Fredette Racing Products

Labor Rates:

Suspension:

Forks

  • $60.00 - Clean and inspect conventional forks
  • $75.00 - Clean and inspect upside down forks
  • $30.00 - Install Race Tech gold valves, cost of gold valves is an additional $169.95
  • $15.00-30.00 - Hone out dents in lower fork tube on conventional forks

All other parts or service work extra call for a quote.

Shock

  • $60.00 - Clean and inspect shock

Items below require above service:

  • $50.00 - Re-valve shock
  • $52.95 - Most seal and bushing heads
  • $125.00 - Re-plate shock shaft
  • $12.00 - Shock bladder

All other parts or service work extra call for a quote.

Engine

  • $165.00 - Porting
  • $65.00 - Mill head
  • $83.00 - Carburetor boring with jets
  • $195.00 - Split KDX engine, all parts are extra

All other parts or service work extra call for a quote.

Call if you have any questions regarding our services.