KDXposed
Can you believe that this man can make any generation KDX go faster than anyone else in the world? Well it's true and has 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 loyalty, commitment, and dedication to transform this undersized trail bike into a competitive off-road race 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, frpoffroad.com is the place to go for all your KDX performance parts, services, and tips.
Frpoffroad.com has lots 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. And if you want your KDX to be the very best, it can be: we offer both engine and suspension shop services.
Long live the KDX!
Accomplishments
- 1970 - Last place in first race at age 12 Hodaka Ace 90 (Trials)
- 1972 Won first trophy at age 14 (Egg Hunt)
- 1974 First enduros as buddy rider behind dad
- 1975 Advance to AMA A rider
- 1977-1978 Penton/KTM Factory Support
- 1977-1997 Overall winner at Illinois Off-Road/Moose Race 7 times
- 1977-1986 AA class rider
- 1977-1986 Overall winner at numerous national enduros
- 1978-First ISDE KTM GS250 gold medal in Sweden
- 1979-1982 Suzuki factory rider
- 1979-ISDE Suzuki PE250 gold medal in Germany
- 1980-ISDE Suzuki PE250 gold medal in France
- 1981-ISDE Suzuki PE250 gold medal in Italy
- 1981 Overall winner at Blackwater 100
- 1983-2009 Kawasaki Factory Support (Hello KDX!)
- 1983 ISDE Kawasaki KDX200 silver medal in Wales
- 1984 ISDE Kawasaki KDX200 gold medal in Holland Top American
- 1985 ISDE Kawasaki KDX200 gold medal in Spain
- 1986 ISDE Kawasaki KDX200 gold medal in Italy
- 1986-2007 Numerous amateur national ice racing championships
- 1987 ISDE Kawasaki KDX200 silver medal in Poland
- 1988 ISDE Kawasaki KDX200 gold medal in France
- 1989 ISDE Kawasaki KDX125 gold medal in Germany
- 1991 ISDE Kawasaki KDX200 silver medal in Czechoslovakia
- 1992 ISDE Kawasaki KDX200 gold medal in Australia
- 1993 ISDE Kawasaki KDX200 bronze medal in Holland
- 1993 AMA Sportsman of the Year
- 1994 ISDE Kawasaki KLX250 silver medal in U.S.A.
- 1995 ISDE Kawasaki KDX200 silver medal in Poland
- 1997 ISDE Kawasaki KDX220 silver medal in Italy
- 1998 ISDE Kawasaki KDX220 silver medal in Australia
- 1998 Grand National Cross Country (GNCC) class winner
- 1998 AMA District 17 AA class winner
- 1998-2004 AMA District 17 enduro director
- 1999 ISDE Kawasaki KDX220 silver medal in Portugal
- 1999 AMA District 17 Hare Scrambles class winner
- 2000 ISDE Kawasaki KDX220 silver medal in Spain
- 2000 On winning team of 24-hour Numb Bumb race in Canada
- 2001 ISDE Kawasaki KDX220 silver medal in France
- 2001 AMA District 17 enduro champion
- 2001 Moose Off-Road series champion
- 2002 ISDE Kawasaki KDX220 silver medal in Czech Republic
- 2003 ISDE Kawasaki KDX220 silver medal in Brazil
- 2003 AMA District 17 enduro champion
- 2004 ISDE Kawasaki KDX220 silver medal in Poland
- 2004 AMA District 17 enduro champion
- 2005 ISDE Kawasaki KDX220 silver medal in Slovakia
- 2005 AMA District 15-17 enduro 2nd O/A
- 2006 ISDE Kawasaki KDX220 silver medal in New Zealand
- 2006 AMA District 15-17 enduro champion
- 2007 ISDE Kawasaki KLX450 silver medal in Chile
- 2007 AMA District 17 enduro champion. District 14: 2nd O/A. District 15: 2nd O/A.
- 2008 ISDE Kawasaki KLX450 silver medal in Greece
- 2008 AMA District 15-17 enduro champion. District 14: 3rd O/A.
- 2008 AMA Grand National Cross Country (GNCC) class winner
- 2008 ISDE Stats: 28 starts and 28 finishes: 10 golds, 17 silvers, and 1 bronze.
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 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.
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 and 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 us 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 to others because of the many variables that exist. Therefore I would ask that you please keep in mind that the following recommendations should be used as a guide line only and that individual rider ability and type of terrain could move you up or down a spring rate if your weight is on the border of any of the specified weight ranges.
Forks
1989-1992 "E" Models: I have found that the stock forks work pretty well for most riders that weigh less than 140 lbs. I recommend replacing the stock springs with a .33 kg spring for riders that weigh between 140-170 lbs, a .35 kg spring for riders weighing between 170-210 lbs, and a .38 kg spring for riders weighing over 210 lbs. For each of these weight categories I recommend setting the clickers between 6-12 clicks out.
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, .40 kg spring for riders that weighing 190-220 lbs, and .42 kg spring 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 us your forks 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 to work for you. I would also recommend that you let us service your shock every 800-1000 mile to prevent premature failure.