Can we discuss the size necessity of fenders?

I've been trying to figure out exactly what size fenders, in terms of length and width, are required in order to be both useful and minimalistic.

So, how far fore and aft of the axle do you need to have a rear fender in order to keep water spray from hitting electronics or the rider. Or same question for the front fender.

Anybody have any knowledge on this? Or opinions? I know there are those that use the stock fenders, cut down the stock fenders, use fiberglass, or make custom fenders that appear to small to be functional, and then there are those that completely delete them. I'm aware that the different types of tire tread will throw water in different ways, but can't find any visuals on where exactly the water fling will come from on both the front and rear tires. A slow motion video of a tire running through water would be tremendous but I can't find one.

My opinion. Any less gets real noticeable very quickly. Any less on the top front fender, you will be blind in the rain. Less on the bottom front and the front of the engine and pipes gets hosed down. You can do less on the top back, but you better like wearing a racing stripe. A license plate can be your friend though. I think it insane to offer less protection for the engine and intake on the back bottom and it is a bitch to clean. You can plan on never riding in less than ideal conditions, but it is like sailing. If you are always going to stay home unless the weather will be perfect, you will never sail.

Makes sense. In your first photo it looks like the front fender ends in the front just slightly past where a vertical line could be drawn from the axle. It makes sense that you would want to have more coverage in the back as the water would mostly leave the tire from the back to 3/4 of the way up maybe? But then, that begs the question of how much coverage you need in the back on the motor side. The reverse of that is the need to keep the back of the motor, especially if you are running open air filters (pods), from getting soaked.

After getting caught in the rain once when I had my front fender off my fighter for paint.....I vowed never to have that experience again.


I don't know about where you are, but over here in Oz the cops will book you without hesitation for having shorter than legal fenders / fender eliminators. Bread and butter revenue over here.

As I was looking into this a bit further I started seeing that there were some states that required fenders. I'm currently in FL and have never seen anything about it being required. I've ridden on wet roads recently on my wifes little CB125 and its currently fenderless in the front, there was a definite vertical spray coming off the tire around 15 mph.