Hi All: I'd like to share my experience in trying to tackle the infamous "elephant trumpet" sound which occurs at take-offs.
If you put up with that awful sound (caused by the clutch's “glazed†shoes slipping while engaging at take offs) well, don’t keep reading.
If, on the other hand, like yours truly, you are totally annoyed by that unbecoming whine, then, you’re on the right topic.
After temporarily addressing the problem a few times by taking the clutch bell apart (for which you need an impact wrench, the nut is 18mm) every 500/600 km or so, to clean it and sand the clutch shoes, I really wanted to solve the matter for good.
I did some extensive online research and considered many options, among which, replacing the stock clutch with aftermarket ones.
I discarded the idea given the cost and after reading that the problem came back notwithstanding the replacing of the part. I finally stumbled upon an Italian forum in which somebody nailed the problem by drilling holes on the clutch bell.
http://lnx.xcitingclub.com/forum/viewtopic.php?f=18&t=5647&p=74367#p74367This mod is a true win-win: it dissipates the heat on the clutch bell and disperses the powder coming from the clutch shoes!
Mind you: this is not a DIY project, at least not completely: you need some shop machinery to achieve the desired result, namely a professional drill bench.
The holes have to be drilled at specific distances to prevent the bell from an unbalanced rotation.
It' a series of two rows of 12 holes each, drilled 30 degrees apart and 15 degrees off one series from the other.
It’s really important the holes be drilled within the operating surface of the clutch shoes (this is easily ascertainable by looking at the inside part of the clutch bell).
I took pics of my clutch bell before and after the “cure†and I’m going to resize and upload them pretty soon.
Cheers!