this is an issue that simply refuses to die,so i thought i would address it.
"moly" is not just moly,there are different types.
it is both true and false that moly can cause your clutch to slip.the word moly has caused such an issue,that some OEM brand oils actually offer two of the same oils,one with moly,the other without.honda comes to mind,so they can sell their oil.
MoS2 is basically an "old-school" type moly that is of a larger particle size and tends to be a greyish powder in look.it is also the one that can build up on your clutch and cause slippage.
MoTDC is different.this is the one commonly found in most modern oils,PCMO or otherwise.it is clear and soluble(it disolves in oil)and does not settle out like MoS2. with this one,you should be good-to-go as far as your clutch not slipping.
now,as far as your clutch not slipping,this is determined by the friction index your oil of choice has,not the amount of moly.there are several factors in how an oil is formulated that determine it's friction index.there are also some OEM clutch assembly designs,particularly on some brands of bikes,that began life on border-line effectiveness to begin with,that has also caused problems and increased the blame on moly.
it would surprise some to know that moly has been in their oil of choice right from the beginning without any clutch slippage.for example,some people that have opted to use mobil 1 15w-50(a typically recommended PCMO for bikes)in lieu of a MC specific oil,might be surprised to learn it actually has moly.if i remember correctly,about 90 ppm. it might also interest people to know that many MC specific oils actually have very high levels of moly.my own favorite MC oil,maxima ultra,has about 380 ppm(no problems with my clutch). at least some of the torco MC oils,have about 580 ppm(although it's additive package is still not as stout as maximas' overall,not even close,lol) which is much higher than most oils out there for any/most applications.some MC specific oils have a little moly,alot or none at all.the same thing goes for PCMO.
if you want to be sure your clutch doesn't slip,stay away from JASO MB rated oils.this oil is better for those bikes that have a separate engine oil sump.
some people have had their clutch slip simply from doing an oil change,even with an oil that should work just fine.some have fixed this problem by simply sanding or roughing the steel clutches.friction clutches can also glaze and/or get burnt.in this case,most of the time,you need to replace them.if your clutch is slipping,fix the problem or they will fry eventually.sometimes the springs also wear out.i have heard of people putting chims underneath the springs to increase pressure,but imo,this is only a temporary fix.there are also high performance clutch packs out there for some bikes.imo,as far as getting no slippage from these high performance parts,the springs can play a more important role but the better clutches also play their part.
if you happen to have a bike that is problematic with clutch slippage(not what you think you know,but a confirmed design weakness)it may be best to stick to those oils that have the actual JASO approvals and not just "meets" or "exceeds",some of these are really great oils.unfortunately,some oils that don't have the actual approvals and are MC specific,are truely awesome oils that have exceptional qualities with formulators that know what they're doing.
having written this,i'm sure the whole "moly is causing my clutch to slip" will never die.
"moly" is not just moly,there are different types.
it is both true and false that moly can cause your clutch to slip.the word moly has caused such an issue,that some OEM brand oils actually offer two of the same oils,one with moly,the other without.honda comes to mind,so they can sell their oil.
MoS2 is basically an "old-school" type moly that is of a larger particle size and tends to be a greyish powder in look.it is also the one that can build up on your clutch and cause slippage.
MoTDC is different.this is the one commonly found in most modern oils,PCMO or otherwise.it is clear and soluble(it disolves in oil)and does not settle out like MoS2. with this one,you should be good-to-go as far as your clutch not slipping.
now,as far as your clutch not slipping,this is determined by the friction index your oil of choice has,not the amount of moly.there are several factors in how an oil is formulated that determine it's friction index.there are also some OEM clutch assembly designs,particularly on some brands of bikes,that began life on border-line effectiveness to begin with,that has also caused problems and increased the blame on moly.
it would surprise some to know that moly has been in their oil of choice right from the beginning without any clutch slippage.for example,some people that have opted to use mobil 1 15w-50(a typically recommended PCMO for bikes)in lieu of a MC specific oil,might be surprised to learn it actually has moly.if i remember correctly,about 90 ppm. it might also interest people to know that many MC specific oils actually have very high levels of moly.my own favorite MC oil,maxima ultra,has about 380 ppm(no problems with my clutch). at least some of the torco MC oils,have about 580 ppm(although it's additive package is still not as stout as maximas' overall,not even close,lol) which is much higher than most oils out there for any/most applications.some MC specific oils have a little moly,alot or none at all.the same thing goes for PCMO.
if you want to be sure your clutch doesn't slip,stay away from JASO MB rated oils.this oil is better for those bikes that have a separate engine oil sump.
some people have had their clutch slip simply from doing an oil change,even with an oil that should work just fine.some have fixed this problem by simply sanding or roughing the steel clutches.friction clutches can also glaze and/or get burnt.in this case,most of the time,you need to replace them.if your clutch is slipping,fix the problem or they will fry eventually.sometimes the springs also wear out.i have heard of people putting chims underneath the springs to increase pressure,but imo,this is only a temporary fix.there are also high performance clutch packs out there for some bikes.imo,as far as getting no slippage from these high performance parts,the springs can play a more important role but the better clutches also play their part.
if you happen to have a bike that is problematic with clutch slippage(not what you think you know,but a confirmed design weakness)it may be best to stick to those oils that have the actual JASO approvals and not just "meets" or "exceeds",some of these are really great oils.unfortunately,some oils that don't have the actual approvals and are MC specific,are truely awesome oils that have exceptional qualities with formulators that know what they're doing.
having written this,i'm sure the whole "moly is causing my clutch to slip" will never die.
