Upsweeps

With upward momentum: High sweep and upsweep silencers:

They or similarly designed end pieces appear in factory accessory manuals in the 1940s. While the entire exhaust system is often installed "with ground clearance" on scramblers, here it is mainly the end piece that points upwards. At least this way you don't scratch the end piece on the curb when parking backwards. Aesthetic reasons, i.e. style, are another reason to crown the Harley with an upsweep or high sweep muffler.

Does a high sweep muffler affect performance?

According to Chat GPT, the additional rear pipe section of high sweep mufflers can also help to accelerate the gases. However, we consider this effect to be rather theoretical. If at all, this effect takes place in the almost unmeasurable range.