Alright, so check it, I finally got around to messing with the top speed on my Honda CRF250R. Been meaning to do this for ages, just never had the time, ya know?
First things first, I needed a decent spot. Couldn’t just rip it on some random trail. Found this long, straight, abandoned stretch of road out past the county line. Perfect, nobody around to bother, and plenty of room to open her up.
Safety check, always gotta do that. Tire pressure good, chain lubed, all the fluids topped off. Didn’t want anything going wrong when I was pushing it to the limit.
Now, my CRF250R is mostly stock. I’ve only messed with the gearing a little bit before this. I wanted a baseline, so I did a few runs in stock form. Just hammered it down the road, GPS strapped to the bars to get an accurate reading.
- Run 1: 72 mph
- Run 2: 73 mph
- Run 3: 71 mph
Okay, pretty consistent. Not bad for a little 250 dirt bike, but I knew there was more in it.
The first thing I did was change the rear sprocket. I dropped a tooth, went from a 51 tooth to a 50 tooth. This would give me a taller overall gear ratio, theoretically increasing top speed. Popped the old one off, wrestled the new one on – that always takes a bit of effort, doesn’t it?
Went back out to my “test track.”
- Run 1: 74 mph
- Run 2: 75 mph
- Run 3: 74 mph
Okay, a little better, but not a huge difference. A couple of mph, tops. I was hoping for more.
Next up, I messed with the gearing even more. I went from a 50 tooth to a 49. This was getting pretty tall, and I was worried about losing too much acceleration.
- Run 1: 76 mph
- Run 2: 77 mph
- Run 3: 75 mph
Alright, Now we’re talking. I got a top speed of 77 mph on the third run! You definitely notice the difference in acceleration though.
