... He supposedly wore down the engine guards to about half their diameter. ...
Just so you know, if you wear the engine guards in half (you can't reduce the diameter of hollow tubes) the bike would go to the ground hard.
He did scrape some metal off the guards.
Overall diameter? Help me!
Diameter is the measurement of a circular item from side to side. If the item is hollow and you remove a portion of one side it is no longer circular. to reduce a diameter the item would need to be solid and worn evenly all the way around.
It was probably more precise than we needed to be. In reading the link it was clear that the author indicated he had worn in spots some of the metal of the engine guards. The engine guards are not flexible. If a rider wore more than just scraping lightly the engine guard the front wheel would be unloaded. When the front wheel is unloaded in a lean the bike will go down.
Willow, sometimes technical precision can be sacrificed in the name of succinctness, especially when everyone reading knows what the writer is talking about. E.g., everyone know that when someone refers to the Valkyrie's differential, they are talking about the gearbox at the rear wheel, even though a differential is actually a device used to accommodate the difference between the two wheels on one powered axle as the vehicle goes around a corner. In the case of RDKILL's description of the worn engine guard, however, technical precision was not sacrificed. Using the word diameter to describe one measurement of a three dimensional object often indicates the overall cross-sectional measurement where the cross section is circular. When someone says half the
diameter is worn down, we know they are not talking about half of the
length of the object being worn. In this case the diameter was 1-1/8". Wearing something down to half of its original diameter doesn't mean that the dimension continues to represent a diameter, but that the new cross-sectional dimension is now half of the dimension that was the diameter, in this case becoming 9/16".