How Much Does a Big Windshield Slow You Down?

Dear Ralph:
Help settle an argument – how much does the windshield effect top speed of a sled? Thanks!

John D.
Indiana

Actually by quite a bit, many miles per hour in fact. It is all about wind resistance and frontal area being presented to the air and the friction it creates. There is going to be a break point for each sled, as you have to take the rider into account as well. Generally, the lower the windshield the faster the sled will be, and the lower to the ground the sled is the faster it will be as well. Sleds that sit tall have a lot of surface area facing forward, adding the belly pan to the hood and windshield. But, with a super low windshield, the rider is going to catch more air, so how far they can duck or crouch is going to play into it as well. On some sleds, a slightly taller windshield might help as it will catch less air than the rider will behind a super short windshield, but again, the lower the faster. Often you will find old sleds that sit lower to the ground are faster than new ones that sit taller, with similar horsepower. That’s one reason why the old ZR 800s and ZR 900 are so stinking fast, to this day, especially ones with out the Diamond Drive. And that’s why the Mach Z 1000 sat lower to the ground, it was meant to be a speed machine, not a bump sled, but some guys couldn’t figure that one out and wanted a (heavy) 1000 with a bump suspension (silly, huh?)
Another thing to consider is the air being caught under the hood. Forward facing ducts catch a lot of air, and if that air can’t get out the back of the hood or engine compartment, it is acting like a wind sail, or like holding a bucket up in the wind. The air has to move freely through the engine compartment, or it is slowing you down as well.