My class 8 with a 5.13 rear ratio at 6000 rpm figures to about 115 mph.
The real question for those that have gone 100+ in the dirt is how fast does it feel.
I have driven 150 mph at the Fontana speedway and while there is no doubt its fast, Its no where near as fast as 100+ in the dirt.
What do you guys think?
Although it's already been mentioned over on the UP board, 118 mph last Friday sitting shotgun with Kyle Taylor in THE trophy truck in Barstow on some frickin goat trail coming down a ridge over by the college and it felt not just fast but ungodly fast. I've been with Greg down pit row at Barstow at about 65-70, too, but it feels different passengering than it does driving.
My XR 650R will hit 105 on pavement with stock sprockets. I had it near as fast the Sunday after the night race on the lakebed. In a wash or on a trail the bike will go a lot faster than about 70 mph which is as fast as I am willing to take it.
i have had my speedo pinned for a few miles straight on the flat graded road out to superstition. I pinned it in 4th, then shifted to 5th and kept accelerating. This was a few years ago when my motor was really strong, and i had 33's with a 3.73 ratio. i don't how fast it was, but it took my friends on a kx 500, and a xr 600 a couple of minutes to catch up with me. I like to think i've gone over 100mph in my truck off-road.
I have to admit that when Scott and I went 131 in Barstow it was my first time ever riding in the truck so I was freaking out as it was. The sensation of speed wasn't that scary or nerve racking but just out and out amazing. It didn't seem like we were going that fast because the ride was so smooth. I had tunnel vision, sort of. Lots of bushes and trees whizzing by and it was fairly difficult to read the GPS well. I've riden in Big Bird a few other times in San Felipe and at the pre-run for Terrible's Town where we got up to around 90 mph in some rougher sections and that's when the sense of speed really kicked in. The harder we hit, the more I realized just how fast we were going. I guess it's all relative. Meaning, the faster you go on a smoother ride, the less it seems like your actually going that fast. Until a bug hits your visor.
The affect of speed is multiplied on any surface you run on that is non-traditional. Just like water. 100 on the dirt is probably similiar to 160 on pavement. I have hit 100 on the dirt and it seems way faster than doing it on the pavement( i approach 100 on the pavement occasionally and don't even realize how fast I am going). I want the motor out of teh 4 cylinder ranger with the 3.73 rearend that went 130+!!!