MO Tested: Bridgestone Battlecross X40 Review
The last dirtbike tire you'll ever need
Okay, maybe it’s not the last dirtbike tire you’ll ever need, but they last a heck of a long time and perform great as they wear. The Bridgestone Battlecross X40 caps off the hard end of the Battlecross lineup and is meant for drier rocky terrain like we see in much of the western United States.
The X40 looks aggressive. The tread design, tie bars, and “anti-degradation fins” all add up to a pretty tough looking tire, but there is some method to the madness as well. Bridgestone’s Castle Block lug design, which has a slightly higher block in the middle of each knob, is used throughout the X40 rear tire. What this does is give the rider a little bit extra biting edge while also allowing for more flex, which, in turn, equals more traction. Tie bars and small fins can be found throughout the riding surface of the tire as well. The tie bars work to better hold the carcass together while the small fins aid with clean-out should the riding get sloppy.
The fins on the sidewall of the tire are meant to act in the same way the fins on your old thumper did back in the day – that is, to dissipate heat. Obviously, the cooler the tire, the less degradation from heat you’ll have. While I can’t say unequivocally that these fins do their job, the tires do last a long time, and even if they don’t, at least they look cool?
The front tire uses similar technology in its asymmetrical design, though Bridgestone didn’t make us aware of any hip marketing terms to use like Castle Block. The front X40 tire uses a different technique, with the outermost knobs featuring a shallow dimple to aid with flexion. Only the knobs closest to the center are solid. The front also uses a considerable amount of tie bars to reinforce the tire.
That all sounds good in theory, right? But what about the real world testing?
Tested to Death
For those who have ridden off-road in the western US, you may be aware of the harsh scenarios tires are put through. Jagged, sharp and/or sandpaper-like rock is the norm here in California where trails are linked together by long dusty fire roads making high-speed blasts through the desert a regular occurrence on a day’s ride. To say the environment is unforgiving for a dirt tire would be an understatement. Think of it more as a torturous environment, where tires end up chunked, peeled, or generally shred to death.
Chatting with a friend who got his first set of X40s just before I mounted up my own, we talked about general tire life on a 500 EXC or similar dirtbike. For the type of riding we typically do, 1,200 miles would be on the low end for a tire that didn’t last too long, and 1,800 would be on the high end. For both of our sets, we amassed more than 2,200 miles on the rear tires before they were nearly slicks in the middle. My friend changed his front tire, “mostly out of guilt” after 2,500 miles. What was more impressive than simply lasting that long were the wear characteristics along the way. There was no chunking of the rubber, no knobs peeling back to expose the tire’s inner carcass, and overall ,no significant wear of any one kind. Between the two of us, those tires took us all across California and into Nevada on week-long trips at times. My friend’s set started their life with a 1,000-mile ride in Baja. The X40 wears incredibly well and the performance delivered along the way doesn’t suffer in the least.
The X40s hook up incredibly well, better than the X30s according to the aforementioned friend. And we’re talking straight-line acceleration as well as out of turns. The sidewall compliance is fantastic in hard terrain and never resulted in a pinch flat even when run at slightly lower pressures during recreational technical riding.
The flexible sidewalls also resulted in making it easier to spoon on a new set which for me, is massive. Changing tires is one of my least favorite parts of riding dirtbikes.
After getting through Baja with my friend’s tires looking as good as they did, I immediately ordered up a stockpile of my own. Bridgestone has had a nice rebate program the last couple of years where you can buy up to a certain number of tires and get cashback on each set. I maxed out the rebate between X40s and X30s. Knowing what I know now, I would have probably just stuck with the X40s.
Speaking of that stock of tires in the garage, I need to go spoon a new set on the 500 so I’m ready for the next dual-sport ride. If you’re in the market for a hard terrain tire and you’re looking for serious performance and serious longevity, I’ve yet to use a tire that’s done better than the Bridgestone Battlecross X40.
Bridgestone Battlecross X40 Tire Sizes
|Front||80/100-21 51M W|
90/100-21 57M W
|Rear||110/100-18 64M W|
100/90-19 57M W
110/90-19 62M W
120/80-19 63M W
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More by Ryan Adams