2017 Off-Road Factory Race Bikes

What GNCC, National Enduro, and Full Gas Sprint Enduro racers demand of their bikes

This article was originally published in the July 2017 issue of Dirt Rider.

There's always a lot of excitement surrounding the first few off-road rounds of the GNCC, National Enduro, and Full Gas Sprint Enduro series. New teams, rider moves, and new bikes made the 2017 season start a particularly interesting one. We combed the pits at the first two rounds of each series to talk to the mechanics and see what settings and performance traits their riders were looking for while prepping for the new seasons.

Mechanic: Tanner Harding

Kailub Russell’s FMF KTM 250 XC-F

Kailub Russell’s FMF KTM 250 XC-F
Kailub Russell’s FMF KTM 250 XC-FShan Moore

Kailub Russell ran a 250F when he won the National Enduro series in 2015, but he’s been riding a 350 in the GNCC series for the past several years. However, during the off-season, the West Virginia rider decided to switch to a 250 for the GNCC series too. “When we’re testing, all the decisions we make are based on a stopwatch,” Tanner Harding, Kailub’s mechanic, says. “This winter, when we were in Florida testing, Kailub decided he would try a 250 against the 350, and it turned out he was faster on the 250. Yeah, there were spots where the 350 was faster, but overall, he turned faster lap times on the 250.

“When I first started working with Kailub, he didn’t have much knowledge of bike setup or even what the clicks did or felt like on the suspension—he hadn’t spent a lot of time messing with it,” Harding adds. “But over the years, he’s gotten to where now he can come in and tell me if he wants the fork two clicks stiffer or softer, or turn the rebound in one or two clicks.”

Kailub runs 100mm of sag. Compared to other riders who like the bike to be a little more active or softer, Kailub wants stiffer suspension with a bit slower rebound so that he gets sort of a “dead” feel. With this setup, the bike doesn’t do anything unpredictable, and if he hits something hard, the bike doesn’t spring back too fast and knock him off line. “He just wants a good, predictable setup that feels good at high speed and doesn’t wear him out,” Harding explains.

28mm pistons
Kailub Russell runs an older front brake caliper, which has 28mm pistons for greater stopping power.Shan Moore

This year, the KTM off-road team is running Neken triple clamps, similar to the ones used by the motocross team, with a 22mm offset. The clamps are paired with PHDS bar mounts to absorb big hits.

The oversize tank is an IMS. Kailub also runs an IMS overflow system, which mounts in the downtube of the frame and catches any coolant overflow and holds it until the engine cools; then it gets sucked back into the system.

The throttle is from Motion Pro and it has Motions Pro’s Titan throttle tube. Kailub wants very little play in the throttle. He prefers the plastic throttle tube because it will spring back into place after a crash or tip-over, where aluminum can bend or dent and eventually make the throttle begin to drag.

seat hump
Kailub is very picky about his seat hump, since he uses it to push off of and “dig” for traction.Shan Moore

The fork is the 48mm WP Cone Valve spring unit, the same as last year, so they’re coming into the season with plenty of testing under their belts.

The P3 skid plate wraps around the engine cases so that it protects the water pump.

Kailub insists on powerful brakes, front and rear, and Harding makes sure the calipers are bled properly before each race to ensure they’re strong and consistent. In the front, Kailub runs an older KTM brake caliper that has 28mm pistons (the new calipers come with 24mm pistons). Meanwhile, the rotors are Galfer items. Interestingly, Harding says that Kailub is pretty hard on rear brakes at National Enduros, but at GNCCs he’s fairly easy on them.

The exhaust is FMF with a titanium Factory 4.1 silencer. Kailub runs a “drop down” header pipe that is considerably longer than stock for more torque and to get a little more low-end hit.

Kailub runs a Dunlop MX3S tire in the front in all conditions. On the rear he runs a Geomax AT81 at most tracks, but in Florida he ran the 18-inch version of the MX11 for the sand.

Kailub is one of a handful of riders who doesn’t like running full-protection hand guards in the National Enduro series, and he carries that over to GNCC, opting to run an Acerbis Uniko “flag-type” guard instead.

Harding takes a large bar pad and fashions a very pronounced seat bump 30 centimeters from the back of the seat. “Russell Bobbitt uses a seat bump as sort of a guide to let him know he’s far enough forward on the seat, but Kailub uses his for traction and to help keep him from sliding off the back of the bike on the hills.”

Kailub likes to rev the 250. When he was riding the 350, Harding says Kailub tended to shift early in the rev range, but on the 250 he lets it wind out a little more. According to Harding, the new 250 has more than enough power and he really doesn’t have to do a whole lot to the engine to make Kailub happy.

KTM is running Hinson clutches in 2017, and Harding says Kailub is relatively easy on clutches even now that he’s riding a 250.

The gearing is 14/51 with Renthal sprockets. The pegs are IMS Core units, and Kailub runs the sharp version for races and the standard version for practice, to keep wear and tear on his boots to a minimum. The brake tip is made by Enduro Engineering, the levers are from ARC, and the fan kit is from Trail Tech through the KTM Power Parts catalog.

Mechanic: Eric Siraton

Trevor Bollinger’s JCR Honda CRF450RX

Trevor Bollinger’s JCR Honda CRF450RX
Trevor Bollinger’s JCR Honda CRF450RXShan Moore

A lot of the items that come stock on the all-new 2017 CRF450RX are a direct result of testing and development from Johnny Campbell's race team. According to Eric Siraton, JCR's race setup from 2016 was the foundation for the new RX.

“A lot of the parts we modified for our racebikes are actually on his bike, like the 22mm offset and the switch back to spring forks,” Siraton says. “There’s also a motor mount bolt that we would shave down to let the front end stay more planted in turns, and that comes stock on the RX now.”

Siraton drills holes in critical engine mounts to allow the chassis more flex. “We’re looking for comfort for the rider,” Siraton says. “Taking away some of the impact from bumps and hard hits.”

motor mounts
Eric Siraton drills holes in some of the motor mounts to allow the frame to flex more.Shan Moore

Siraton also plays with torque specs for engine mount bolts to find just the right feel that Trevor is looking for. “On an aluminum chassis, the torque specs on engine mount bolts, swingarm, and linkage bolts is very critical to the compliancy of the bike… It can make a big difference in how the bike feels and handles.”

Siraton says the Xtrig triple clamps are a little more compliant than the stock units.

Trevor likes the bike to stay planted when he hits big bumps or goes through rough sections. Trevor runs the stock 49mm Showa fork, revalved by Pro Circuit and serviced by Motovation.

JCR runs Pro Circuit exhausts, and they're still in the process of testing. "The first set of pipes we got from Pro Circuit, the power delivery was a bit interesting, so it was just a matter of matching the mapping to the pipes," Siraton says. "The bike is so new that it's an ongoing process with the aftermarket companies as far as developing products."

Pro Circuit supplies the exhaust system
Pro Circuit supplies the exhaust system for Trevor Bollinger’s Honda.Shan Moore

Trevor likes a progressive feel to his brakes, especially the front brake. He wants them powerful but not so sensitive that the front wheel tucks when he touches the front brake. “It’s a fine line between the brake fluid we use and proper bleeding,” Siraton says.

Trevor is a “smasher,” according to Siraton, and sometimes he just hammers through lines, so Siraton has to keep an eye on his brake discs and make sure they’re straight after each ride.

Siraton adjusts Trevor’s power delivery through mapping and programs the engine to match the Pro Circuit pipes with the end goal of a smooth, progressive delivery. Trevor is coming off a 250 and he likes to rev the bike, so Siraton adjusts the power to accommodate that.

Bar position is one item that Trevor is picky about, and he likes his 999 Renthal bar laid back in his lap a bit, which helps with cornering.

The calipers, rotors, and pads are all OEM; Trevor can go three races before he needs to replace brake pads. Trevor normally uses the Maxxis SI tires front and rear, but for the Florida sand he ran the Maxxis IT. Trevor runs a Hinson clutch basket, which is a seven-plate system. The chain block is from BRP, the seat foam is stock, but the cover is from Throttle Jockey, which gives better grip.

National Enduro
Mechanic: Tanner Tremaine

Thad DuVall’s Rockstar Energy Husqvarna Factory Racing FX 350

Husqvarna Factory Racing FX 350
Husqvarna Factory Racing FX 350Shan Moore

Thad DuVall is hard on rear brakes, especially in National Enduro competition. Because of Thad’s “love” for the rear brakes, Tanner Tremaine is either bleeding the rear brakes or replacing the pads in between each test.

The rear brake caliper is a factory Brembo unit with 26mm pistons, which is available from Husqvarna. Thad also runs a solid rear rotor to help dissipate the heat. The rear brake pedal is adjusted a little lower than normal so Thad doesn’t accidentally drag it.

The bar is a ProTaper Fusion. Thad is the only rider on the team running a crossbar. Tremaine says Thad likes the visual of running a crossbar.

The one thing Thad is pickiest about is his hard guard placement, and he runs them relatively low. He runs full wraparound hand guards for National Enduro and flags for GNCC.

Thad DuVall
Thad DuVall runs a solid rear disc.Shan Moore

Thad did extensive testing with FMF exhaust systems. In the end, he went with the straight “shorter” header pipe because he rides higher in the rpm range and it suited his riding style.

The clutch is a Rekluse Torque Drive. Tremaine tells us Thad was hard on clutches at the start of the season, but through testing he figured out they were running too small of a rear sprocket; after gearing the bike down a bit Thad’s not nearly as hard on clutch plates. The gearing now for Enduro is 14/51. For GNCC racing he runs a 14/50 combination.

The footpegs are IMS off-road pegs, with the “duller” spikes. Thad tested the regular and the sharp pegs and felt he couldn’t get his boot off the peg as well with the sharper versions.

Thad likes the Dunlop MX3S and runs it on the front at every round. For the rear, he prefers the MX3S but will sometimes switch to the AT81 for certain conditions.

Neken triple clamps
Thad runs Neken triple clamps with stock 22mm offset.Shan Moore

For National Enduro, Tremaine uses an auxiliary cooling fan on the radiator, which runs off of a heat sensor placed in one of the coolant lines.

Thad is very specific when it comes to his seat hump, telling us he likes it 16 inches from the back of the rear of the seat to the front of the hump. He also has it covered with a pleated seat cover.

Thad’s radiators are stock, though he has a 2.0 bar cap due to the extreme heat of stop-and-go racing in the National Enduro series.

Tremaine says that for some reason Thad kicks his right leg around a lot more than he does his left leg when he’s racing, and so he is extremely hard on his right-side number plate. Tremaine also says Thad bangs up exhaust systems on a regular basis. Tremaine carries a spare engine on the team rig, but he concedes Thad will go half the season before his engine is due to be swapped out. Team Husqvarna runs a datalogging device that records engine temperatures, and if an engine stays over a certain temperature for a specific length of time, it will automatically be replaced.

Mechanic: Zack Huberty

Jordan Ashburn’s Beta USA 430 RR

Jordan Ashburn’s Beta USA 430 RR
Jordan Ashburn’s Beta USA 430 RRShan Moore

Jordan Ashburn is running the GNCC series plus the Full Gas Sprint Enduro series in 2017. Jordan has a very smooth riding style, and, quite noticeably, he likes to lug the engine in a taller gear (usually third in the Enduro tests).

“The 390 was a great bike and it had a lot of good bottom-end, but it didn’t seem to rev as far on top as what Jordan was used to,” Jordan’s mechanic Zack Huberty says. “He tried the 430 at the dealer meeting this year but was afraid it would be too much power, but overall the 430 has a smooth delivery of power and it revs further, so it ended up being what Jordan was looking for.”

Jordan doesn’t like a loud pipe; he wants it to be fairly quiet. So FMF built him a longer silencer, though Huberty removes the insert to let the bike breathe.

Beta USA
Jordan Ashburn doesn’t run a kickstarter, so the team uses an aluminum plug made in-house by Beta USA in the side case.Shan Moore

Jordan uses a floating front rotor, which he says gives him a bit more stopping power. Jordan relies more on the front brake than he does the rear.

The kickstarter is removed on Jordan’s bike, along with the gears that work with the kickstarter. This is a weight-saving modification. Beta USA makes a plug to fill the hole in the case where the kickstarter would go.

Unlike teammate Drew Higgins, who runs a Washougal tire at just about every race, Jordan likes to try different tires for different courses. At the Georgia Full Gas Sprint Enduro, Jordan swapped wheels for every test so he could run a sand tire in the Cross test and a Washougal in the Enduro test.

The suspension is relatively stiff. Since Jordan stands more than a lot of riders, he’s able to absorb a lot of the small stuff with his legs.

The Beta team makes a lot of its own “aftermarket” items in-house, like this sharkfin.Shan Moore

The pegs are IMS Core models, and they’re super sharp. Jordan doesn’t like his boots to slip off at all, and, according to Huberty, he’s pickiest about the brake side.

For gearing Jordan runs a 13-tooth in the front and a 50 in the rear. He started the year with a 13/49 combination but felt he got better traction with the 13/50 setup.

Jordan runs ODI half-waffle grips. According to Huberty, he’s very picky about grips. “He doesn’t like grips that are really soft. He doesn’t want them to mush and roll over; he likes them fairly firm.”

Since Jordan likes to lug the bike, he also uses the clutch a lot, so Huberty changes plates for every race just to be safe.

The front brake lever is moved in on the bar a little to give Jordan a little more leverage for the pull. The clutch lever remains in a more “standard” position.

For the Florida GNCC, Jordan ran a 19-inch rear wheel so he could ride an aggressive, one-off Kenda sand tire that only comes in 19-inch.

National Enduro
Mechanic: Chad Froman

Jake Froman’s Ol’ Red Racing GasGas EC 300

Jake Froman’s Ol’ Red Racing GasGas EC 300
Jake Froman’s Ol’ Red Racing GasGas EC 300Shan Moore

According to Chad Froman, father and mechanic for Jake Froman, turning is the secret to success in the National Enduro series, and Chad experiments a lot with fork oil viscosity and oil level to get the desired handling feel with the 48mm Marzocchi fork that comes stock on the 2017 GasGas. “We go with 300cc of fork oil and 105mm on the sag, and that seems to be the magic numbers for Jake,” Chad says.

Jake prefers his suspension to be on the stiff side. “We try to keep it plush for the roots and rocks, but we want it to ride up in the stroke so we run the suspension on the stiff side,” Chad says. In addition to playing with oil height, Chad runs stiffer springs, going from 4.2 N/mm to 4.6 in the fork.

As far as power delivery, Jake likes a hard hit on the bottom so Chad gets the GasGas to bark in the low end by adjusting the power valve. He also runs a high-compression head, which is made by S3.

adjustable compression
Jake Froman runs an S3 head with adjustable compression.Shan Moore

One of the biggest modifications is a Lectron Power Jet carburetor, which Chad says simplifies the pre-race routine because there is no need for jetting.

There are a lot of Enduro Engineering pieces on Jake’s bike to protect vulnerable areas, including radiator guards, skid plate, and disc guards.

Jake is super picky about his front brake and likes it to be super sensitive and powerful. “You just have to touch the front brake lever and it’s on,” Chad explains.

Jake is hard on rear brakes but not excessively so. Chad bleeds them after every test at certain events. The rotors are stock with EBC brake pads.

Jake uses a lot of clutch at the tight National Enduro rounds, and since Rekluse doesn’t make a Torque Drive model for GasGas, Jake runs the stock clutch plates with a Rekluse basket.

two-piece rear fender
Froman seals the two-piece rear fender with silicone to keep it from filling with water.Shan Moore

For gearing at Enduros, Chad goes from the stock 48-tooth rear sprocket to a 50-tooth sprocket.

Chad removes the cooling fan thermostat because he feels it restricts the flow of coolant. Ol’ Red coolant, which is a title sponsor for the team, is used in the radiator.

Jake usually runs a Kenda Washougal rear tire; including in the sand at the Alligator National Enduro.

The rear brake master cylinder banjo bolts have a built-in switch for a rear brake light and Chad replaces these with standard Nissin banjo bolts.

The rear fenders on the GasGas are two-piece. Chad packs the void in the center of the two pieces with silicone so the fender doesn’t fill with water and funnel it to the air filter.

The exhaust is an FMF Gnarly with a Q Series silencer, the seat cover is an HBD Gripper model, and the bar is the Renthal 999 bend.

Sprint Enduro
Mechanic: Ryan Belue Crew Chief: Corey MacDonald

Josh Toth’s AmPro Yamaha YZ250FX

Josh Toth’s AmPro Yamaha YZ250FX
Josh Toth’s AmPro Yamaha YZ250FXShan Moore

One cool modification that Crew Chief Corey MacDonald came up with two years ago is to trim 8mm off the radiator mounts on each side to make the Yamaha 16mm narrower. It doesn’t look like that much difference, but when you sit on the bike you immediately see (and feel) it.

Mechanic Ryan Belue installed Ride Engineering 23.5mm-offset triple clamps on Josh’s bike (25mm is stock). The team does away with the rubber mounts and builds their own cones so the Precision Flex Mounts bolt solidly to the clamps, eliminating any chance the bar will shift if the rider should tag a tree.

The AmPro team runs an IMS YZ tank for GNCC, which increases the fuel capacity over the stock FX unit, but for the National Enduro series Josh had on the stock tank.

Factory Connection
Josh Toth runs a Factory Connection link that is 1mm longer, so the bike squats a little more.Shan Moore

Josh uses a G2 throttle system with a slightly faster throttle cam for the sand races. Josh and teammate Ricky Russell both run bar ends to protect the grips.

MacDonald adds a couple of welds on the swingarm to strengthen the chain guard mounts, and he told us the new Bullet Proof chain guard mounts are a lot stronger this year. The chain guide and sharkfin are TM Designworks.

Factory Connection does the suspension and tested with the team the week before the Florida round. Since Josh is a shorter rider, he runs a Factory Connection linkage that is 1mm longer, so the bike squats a little more.

The hubs are by Dubya, which use larger bearings than stock, and MacDonald says they last a lot longer. The front and rear hubs use the same diameter bearings, which is nice for carrying spares.

Josh is extra picky about his front tire selection, and after a lot of testing, he went with a Kenda Washougal up front for the sand, but he likes the Kenda Triple for harder surfaces. He was running a Southwick in the rear in Florida for the sand. For intermediate terrain he prefers a Washougal II.

AnkleSavers footpegs
The AnkleSavers footpegs look like something out of a sci-fi movie but are made to save your ankles on big hits.Shan Moore

Inside the tires is a new mousse made by Nitro. Josh likes to break in his mousses in his practice bike before he runs them in his racebike.

Belue does away with the oil overflow tube that runs from the valve cover into the airbox. Instead, he blocks off the airbox hole and uses an oil line from an older YZ model and vents it out behind the skid plate. Otherwise oil could go through the airbox and into the throttle body, which can cause loss of power; this eliminates that possibility.

The exhaust is an FMF Megabomb with a full titanium Factory 4.1 silencer. The clutch is a Rekluse Torque Drive unit, which Josh likes to abuse. The levers are GYTR “break-away” items under Cycra hand guards; Josh is picky about lever placement but runs them in a relatively neutral position. Works Connection provides the radiator braces. Josh runs the lower Renthal 999-bend handlebar and 13/50 Renthal sprockets.