They are just big heavy, slow chinese style pit bikes.
K
You must be confused with another bike. Any special will only be as beautiful as the creator sees fit and yes some look better than others. The same can be said of any two standard bike. You get some pretty manky Red (blue yellow black white) Rockets at the same meeting as new ones fresh from their photo shoots. Doesnt mean they are all great or all manky...
Yes they can be slow and heavy, but Chinese style pit bikes, I think not! (if the chinese are making replica HLs let me know, their stuff is getting quite good)
Slow? Obviously a lot comes down to the rider. If you saw 40+ 4 strokes head into the first corner at Farleigh (yes HLs included) the last thing on your mind would how slow they were going!
Rod Spry had a fast chap on one of his JBRs (yes I know it's no a Yamaha HL, but it is a close relative) and people were awestruck (and rightly so) how quick he was on the bike.
Eating establish fast riders for breakfast on the tricked up, blinged out, read valved 490s was common place.
A fast rider on an well sorted bike is a good receipt for success whether the bike is a 2 stroke or a 4 stroke.!