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How bad does the weather have to be before Canadians decide it’s too cold to ride? We check out one of the most extreme rides on the planet, the Numb Bum 24 Hour race.

It’s not unusual here in Oz to get a day that’s too hot for riding, but would you believe it happens in Canada? For the Numb Bum 24 Hour race the temperature can’t be too far above freezing. Charlie Dyer has taken over the running of the Numb Bum so I got the good oil straight from the horse’s mouth.

The Numb Bum 24 Hour is an ice race held on a frozen lake in Canada’s winter when the ice gets to a thickness of half a metre and the race is held no matter the temperature or track condition and temperatures range from +5° to -50°. Our source for this story, Charlie Dyer, tells me he has raced with 100mm of water on the ice at the start because of the plus temperatures and finished at -30°. Charlie is 66 and has started the Numb Bum 17 times. He’s a multiple winner as are his two sons. Last year he raced with one son and two friends and finished in second place over-all in the Pro Open class.

The race originated in Grande Prairie, a town of over 60,000 people in the province of Alberta then the next five races were held in Fairview about 100km further north before returning to Grand Prairie. After a few years without any race it was resurrected 500km to the east in a place called Sandy Beach and held there for 25 years but in 2024 it will be back home in Grand Prairie.

The course changes from year to year but normally it is about 27km long and is a fairly smooth road race style circuit with no jumps or MX type obstacles. The track is 20m wide with straights where riders can get above 150kph and corners where speeds can be as low as 6kph. Racing runs from noon Saturday to noon Sunday and there is no problem finding your way around the 27km track as the snow banks left by the track making snowplough are a metre high or more.

Competitors run a transponder on their bike that tells a computer each time they pass the enclosed trailer housing the lap scorers. There is a computer screen in the trailer window that the riders can check on to see how they are doing, it’s important to keep track as the total distance can exceed 1500km and up to 60 teams can be racing.

The Numb Bum is primarily a team event but there is also an Iron Man Class for those who think racing in sub-zero conditions isn’t tough enough on its own. One year it was an Iron Man competitor who logged the most laps overall, he’d have to be the type of bloke who could chew four inch nails and shit horseshoes.  Other classes are Pro Open, where you can run any bike, the Under 251cc class and the Red Eye Class which is any capacity but only races from noon to 6pm Saturday then starts again from daylight on Sunday until noon. Bikes are fitted with screwed steel tyre studs for traction on the ice and have protective guards around the wheels to shield fallen riders and despite all the adverse conditions there have been very few injuries in the history of the event.

The Numb Bum is a big thing in Canada with Canadian pollies, footballers and hockey players all taking turns at being honorary starter with one year Evel Knievel doing the honours. There is no prize money only bragging rights for competing, finishing or surviving the -50°C conditions at 150kph. The Numb Bum is a stand-alone event and has competitors attend from all around the globe to see if they can finish what has to be the toughest race in the world. There is no cap on the amount of team members, providing you can find them, then convince them it’s a good idea. Many teams have been competing for years, Charlie’s team operates on shifts of about 90 minutes for each rider but you have to wonder how long it takes to thaw out afterwards.

Charlie told me of one year when it was five degrees and raining and he was getting soaked from passing other bikes and his boots were filling with water. He was KTM 530 XCW mounted and it was geared for 170kph and he was looking for another gear at times. He also mentioned a few years ago a Quad class was introduced so you have them out on the track at the same time.

Just to make things really interesting the ploughs go out to maintain the track during the race. That brings us to a rather unique rule, the likes of which we’ll bet you’ve never heard of before. The snow ploughs are tractors and pickup trucks fitted with blades and if you hit one on your bike, then you have to pay for any damage you cause.


It takes a while to build a bike for the Numb Bum, up to two weeks Charlie tells us. He runs tyres built in eastern Canada by a bloke called Karl Daigle and it’s a job that takes days. Once built though the tyres hook up so well with the studs biting into the ice that it’s possible to scrape the footpegs. To last the distance tyre pressures are higher than normal dirt riding at 26psi and heavy duty 4mm tubes are run as well and of course the wheels are carefully balanced.

Charlie rides in a team with three others so suspension has to be set at a happy medium to allow for different weight riders and riding styles. A hand-built chain guide is fitted to the swingarm to keep the chain from snagging on the studs. Gearing is high with Charlie running 13/48 sprockets on his CR500 and is still looking for an extra gear on the straights. In case bike and rider should part company, a tether is used to kill the engine as the rear wheel could cut a rider in half in seconds if the throttle was jammed open.

Due to the huge amount of side torque during the race, brand new wheel bearings are fitted beforehand and the spokes are checked and carefully tensioned. Wheel guards are also fitted front and rear for protection in a crash and tyre covers just to help roll the bike around. The studs are sharp enough to cut your leg just brushing past so the tyre covers are a must in the pits. Charlie’s team usually has three rear and two front wheels with tyres as spares.

Heated grips are a necessity along with Barkbusters and wrap around covers. A larger stator is necessary as the race runs for more hours in dark than daylight. LED lights are a big improvement over what was available in the past as you can never have enough light Charlie says. The cold has never given any problems with fuel and he runs normal anti-freeze and 10/40 engine oil even at -50°C temperatures.

When the build is done and it’s time to practice Charlie tells us he ploughs a practice track near his house which takes about six to eight hours to complete. Imagine if you had to build a new practice track every season. Charlie has been doing exactly that for 25 years.

Come race day everything is transported out to the ice with a heated trailer to keep the bike in, along with a heated 10×20 foot portable garage for any work that the bike may need in pit stops. Then it’s just a matter of racing for 24 hours in below freezing temperatures on ice. What could be simpler?


One year Charlie had prepped a XR600 Honda for his team and a company that makes oil additives sponsored him with a kit to add their product to the bike.  He poured it into the dry sump and took the bike to the race. A TV company was doing a segment called On The Road Again about the Numb Bum and the host was Wayne Ronstad a Canadian musician and TV host who would be riding an XR600 Honda also.

In those days the race was started with the bikes lined up three abreast and Charlie’s mount was in the third row. The team hadn’t run the bike with the oil additive in it at that stage. The temperature was -35°C on the day and Charlie was the starting rider on his team.

He only made it about half way when the rod came out between the bottom of the cylinder and the transmission. He pulled over and looked at the damage and you can imagine the words that came out of his mouth. Wayne Ronstad stopped there as well saying he was freezing to death and that he couldn’t carry on as he was just way too cold. Charlie asked if he would like him to ride his bike back to the pits and he said yes.

The race organizers had a snowmobile with a trailer to pick up dead bikes and he told Ronstad to just wait there and they would come and pick him up. Charlie’s team had a backup bike in their pit so he knew he needed to get there fast. He went sailing into the pits and all his team mates were wondering where the hell he had been. He told them to get the backup bike out but they were wondering what’s wrong with the bike thinking this bike of Wayne’s was theirs.

Charlie was trying to tell them but was in a hurry to get back out on the ice and keep racing. They got the backup bike started and he hustled his bum back out and into the race again doing another 10 laps then came in for fuel and a rider change. The crew was all over him about this other 600 bike and he finally had time to tell them.

He then went down pit row to find Wayne to thank him and he told Charlie a story that was going around the pits. It was about a guy that had broken down and had stolen a bike from another rider when he stopped to help. That’s the story that was being passed around and they both had a good laugh over it.

For the full feature, check out issue #532 of ADB.