CLUTCH DUST
Hope this helps . For many years I thought the dust was coming from spring too tight or gap to far . When a customer would come in for us to set the clutch we would set it with the spring not too tight and close gap , figureing when the shoe breaks in he would be at the right gap . Well we had many clutch dusting actually all of them did. My opinion from my trials and error when spring too tight or gap too far you shoe will burn and turn black . A little brown on the yellow shoe ok as long as gap stays the same . The dusting actually comes from not enough spring tension or not enough gap . The clutch shoe dont have enough rpm to lock into the bell and spin the wheels so it then bounces on and off the bell till it grabs causeing dusting . When we made our gap between .7 and .8 we stopped the dusting . Example : real car manual transmission not giving enough rpms while releasing the clutch car will buck . same thing happening with clutch bell .
We struggled with the clutch for years and if you dont pay attention to it often , you will lose the good setting . Some guys were running .4 to .5 gap which i dont advise . i seen a top driver suffer with his clutch at preworlds and i know he runs .4 or .5 gap . Depends on tracks traction but This is what i advise for mugen 3 shoe clutch .
Take inside bearing out of the bottom of the clutch bell so bell will rest on shoe . measure your gap , if new shoe you can set to .7 if used and in good condition .8 . your measureing of this gap is critical for the a good clutch . i advise checking it every run till it stops changeing and broken in . Then put inside bearing back in and put shims which usually equals about 1.3 to 1.5 to bring bell off of shoe . this will stop bell from rubbing shoe when you come off throttle and also roll around corners better with no drag of engine .
Now comes the spring tension . the problem is you never know how much to tighten . You can start at factory settings and tighten down spring till you get desired power from bottom end but if you start losse and keep tightening you can go down till it starts to slip then back it up . if you here slipping on track then you went too far and will burn the shoe .
I can only talk from my expierence and know this to be true . Hope this helps . yes also dusting problems can come from bent pressure plates since they are lightweight aluminum now , if 1 flyweight gets hung up it will bend plate . bad clutch bell will also do this . good luck
Richard Siriano
Team mugen northeast
Team Brooklyn Hobbies
see everyone in florida at the state race in homestead !