4-Smokes and Mud

Probably because they were not riding them as if they were doing a 3 hour race

Kinda blows my mind the teams aren’t putting in a waterless coolant like Evans in the bike for the mud races.  The boiling point is like 375 degrees on that stuff 

4 strokes also race in the mud in GNCC. The teams don't switch to two strokes for mud races. 

Wasn't it muddy at the National they had at LL in '20?  And Eli blew his bike up both moto's?

Short answer: Heat

Long answer:  It's interesting that the professional teams don't default to a closer to stock engine and suspension package for mud races.  
When they do tech inspection they don't know exactly the track conditions for the races. 
What all can they change on the engine after tech? 
Is it better to be stuck with something slower but more reliable on a decent track? Or to be crossing fingers hoping the race spec engine finishes a mud race?

When Justin Rodbell was asked about it, he said it was because they were idiots. 

The GNCC crew has proven that a mostly stock engine can do 3hours of mud.  Matthes said GNCC has some open areas which allows the bike to cool, and that is true, but GNCC also will have 10-20 minutes of slower sections before they get the open areas, so the logic doesn't follow.

^Running a more "stock" engine configuration would be the very first thing I would do, but what the hell do I know? 

There is definitely some differences but to have so many barely make it 10 minutes is pretty crazy. Stock engines would have to help I'm sure but I think the biggest issue is these guys are just abusing the clutch making tons of heat. They do pressure wash the radiators out at the pit stops but you still have to make it around a 20-30 minute lap. 

Lots of guys still blow up bikes in GNCC you usually have way more puddles so they are also dealing with sucking water into the engines as a DNF reason along with them overheating.

I thought that too during the broadcast; I wonder if they threw stock - ish motors in to save their expensive mod motors. Maybe the privateer teams do to save money? 

It's the clutches that go usually, on gncc they're not on the gas and clutch like moto guys. Off-road you generally use the throttle more for power modulation because the races are so long. Moto guys will toast a clutch in a single moto.

Stock motor would require less force on the clutch components, right?

Spot on! All the heat comes from the clutch. It especially affects bikes that share engine and transmission oil. 

I just find it odd how opposed these guys are to making big changes for these mud races, in a race like that where its obvious you aren't doing the jumps why are we not running a soft mud setup and a somewhat stock motor and change your riding style so you arent abusing the shit out of the clutch. 

Obviously you've not been to one of those 3 hour races. Those bikes are getting hammered for 3 hours. 

That's what I run. I've gotten the bike so hot with while running Evans that the overflow tube melted shut, and the engine sounded like a diesel at the end, but I finished. Was on the bike almost 4 hours that day

My 350 didnt survive The Wild Boar either running Engine ice and a radiator fan. Blew out the cam tensioner.

Bikes built for different purposes have different specs and applications. You wouldn't expect a dragster to run a nascar race.

In the mud you back off the tune for both the engine and suspension, but you can’t go full soft on the suspension because of all the extra weight.

I do believe 4t’s run hotter in the mud than a 2t, but a 2t will usually fry the clutch quicker because you need it more. Also who remembers the struggle to keep a highly strung 2t together in deep sand? Detonation, steaming radiators and cooked piston’s for days.

Horses for courses, and as usual everything you do is a compromise.

I was watching that race and thought that for extreme mudders like this, why not have a "water trap" that could be implemented as a race day call, it would be sort of a tribute to the early days of SX as well. The new trap would basically be a 4-6 inch deep pool with a grate bottom that is around 20 feet long, track width. This clears some of the slop off the bikes as racers go through, which would help them run cooler and and should makes the bikes and riders easier to follow and score as well. Obviously it would only be used for extreme conditions, but it could make the racing easier to follow and maybe save some DNFs.

Are the mechanics allowed to spray the bikes during the race?   There are portable high pressure water sprayers for not a lot of money.