You do not have to use the clutch if you are a good shifter, but why wouldn't you? Why put any extra strain on your equipment?
The UCE is a good shifting bike. Some things are important
1. chain adjustment - seena lot of complaints that this clears up. It gets forgotten but is very important for the life of the chain, transmission and primary.
2. clutch adjustment - also overlooked
3. technique. This is the one we see the most on bikes that people swear jump in and out of gear, wont shift etc. (This conversation applies to the 5 speeds only)
I don't mean to insult anyone but we have seen this a lot. Generally speaking it is people that come off of sport bike, have new boots or are pretty new riders. Simply put you must shift firmly and fully. when you shift from one gear to the next you have to release the shifter so that it goes back to the neutral position before you put it in the next gear. ( I don't mean put it in neutral but I do mean let the shifter center it self and then shift