Mud Prep With Pro Circuit

Be Ready For Rain

From the July 2016 issue of Dirt Rider Magazine

When it looked possible that Anaheim 1 earlier this year (2016) was going to be a mud race, Joey Savatgy’s mechanic Justin Shantie prepared a “mud bike” for Joey. The skies held, so this bike stayed parked, but we got Justin to walk us around the bike to show us how it differs from Joey’s “dry bike.” Then we got team owner Mitch Payton and Suspension Technician Jim “Bones” Bacon to tell us what goes into the internals of the engine and suspension if the race is going to be a mudder.

Mud Prep with Pro Circuit
Pro Circuit Mechanic Justin ShantiePhoto by Pete Peterson
Mud Prep with Pro Circuit
1. “In the airbox we put carbon on both sides. The one side, we always run for sound. I do it on the other side just for the water splashing. I don’t know if it takes away from the power or not, but you just want to be able to keep water out of the filter ’cause a runnin’ bike is good enough for the mud. “The airbox is all closed off in there except for the bottom. We’ve got what we call a shower cap from Twin Air. It’s a screen over the air filter. It gets air through it fine, but it repels the water.Photo by Pete Peterson
Mud Prep with Pro Circuit
2. “I add a boot to the bottom [of the airbox], so when you’re splashing through the water the water can come out, but it’s harder to go in. It’s a front inner tube bolted on the mud flap. It can compress with the swingarm and the water can run out of there. I try not to put any foam in the bottom of the airbox so the water can get out. “If it was really watery or raining I’d probably put a V-channel in here [on top of the rear fender, under the seat] to keep the water from running [into the airbox].”Photo by Pete Peterson
Mud Prep with Pro Circuit
3. “I put standard mud foam everywhere. You don’t want mud to pack in under the engine and get the engine hot. I put it on the brake pedal. You don’t want it to pack inside there and keep the brakes down. If the conditions turned really bad, I’d add foam around the shifter.” Bones says that if it’s still raining, the mud is less likely to stick to the bike so they often won’t compensate for the added mud weight. But if the ground is wet and the skies are dry, Bones recommends sliding the forks down in the triple clamps to raise the front end. In sticky-mud riding, Bones also suggests stiffening up the fork and also increasing shock spring preload to start the race with a little less sag, so once the mud sticks the heavier bike will ride at approximately your normal sag setting. He watches bikes coming off the track to approximate how much weight the bike and rider are likely to gain once hitting the sticky stuff. If your bike has an air fork with an adjustable balance chamber, Bones says consider lowering that balance chamber pressure to raise the front end’s ride height. If your coil spring fork has an external preload adjuster, dial in a little more preload. As for clickers, Bones says if the mud is sticking, one or two clicks stiffer on fork and shock compression might help, and if you add a lot of spring preload (or lower the balance chamber pressure in an air fork), a click or two slower on rebound might help the bike react more normally. Of the suspension settings, the fork height in the triple clamps and the preload changes are the first and most significant steps. For the average guy, chasing clicker settings around the conditions might be overkill.Photo by Pete Peterson
Mud Prep with Pro Circuit
“We run bigger radiators and screens on the louvers for mud. You want airflow. We use a special plastic screen zip-tied on there. The radiators are a lot bigger. They’re actually outdoor radiators; it’s an SR Kawasaki part.”Photo by Pete Peterson
Mud Prep with Pro Circuit
4. “We add an oil cooler. We don’t usually run it in supercross unless a guy’s really hard on the clutch. It’s more of an outdoor thing. “I put a skinned header on it in case the rocks get really bad.”Photo by Pete Peterson
Mud Prep with Pro Circuit
5. “We have two different types of calipers. The caliper on the dry bike is a lighter, smaller version; everything is about weight for that bike. This one on the mud bike is an outdoor caliper. It’s a little bit wider, and it’ll take more of a brake pad, so a little more material. The mud going through it will chew it down, but you can’t run the dry bike once in the mud because there’s only about a third of the pad there. “If it was raining, I’d go to Dunlop and get the MX11, the mud tire, put on. I’d use the same front tire [as normal] because right now he already runs a front tire that doesn’t pack with mud. “The full pleated seat is actually a mud seat, but the guys started running it. It’s on both bikes ’cause of the grip.”Photo by Pete Peterson
Mud Prep with Pro Circuit
6. “We use a higher-pressure radiator cap. You want to keep all the coolant in the bike. Keep the water out and keep the coolant in.” Mitch Payton adds that running a brand-new cap will ensure you don’t lose pressure. “I use the same coolant. I just make sure it’s brand new out of the bottle when I build a mud bike or outdoor bike or anything that’s going to just try to pump up the temperatures right away. The mud gets on and they get super hot.” Mitch doesn’t recommend much in the way of FI tuning for mud but says they might go 1 percent or 2 percent richer for mud, which is a very small increase.Photo by Pete Peterson
Mud Prep with Pro Circuit
7. Justin might also add hand guards, and for the average racer a fresh clutch pack is a smart precaution before hitting the slop.Photo by Pete Peterson
Mud Prep with Pro Circuit
8. “I do try to sharpen the kickstarter to a point, so if it’s really muddy, maybe it’ll grab a little bit extra. I didn’t personally do it. I took it over to our porting guy, and he put a nice edge on here so Joey’s boot wouldn’t slip off. “I’d do some SC1 or some Pam, like for baking pans, under the fenders just to get it to not stick.” [Be sure not to let it drip onto the brake.] “For Joey I’d probably have a towel in his waistband because he wears wrist braces, so it’s really hard for him to change gloves. I give him a towel to get the mud off his hands if he falls.”Photo by Pete Peterson
Mud Prep with Pro Circuit
“We have a hard brake pad, so you don’t run out of brakes, and we’ve matched that with a solid disc rotor. The mud on a standard rotor. If it’s a really sticky mud, it’ll get in between the rotor’s holes and it’ll just burn the brakes up.” Mitch Payton adds that they rarely change the bike’s gearing, but if the conditions are extremely deep and loamy they might put on a rear sprocket with one more tooth than they normally run so the bike can pull through the deep mud easier without lugging down.Photo by Pete Peterson