Originally Posted By: j454
Thanks for the feedback. I guess I've since learned that the Mobil 1 TDT oil has little to no friction modifiers in it as well the motorcycle oils don't. With these types of oil not having friction modifiers and they are higher quality oils, why is it a good thing to have friction modifiers in oil in the first place? Or what am I giving up when not using an oil with friction modifiers? Thanks
Try this link:
http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=729029#Post729029
You can do a search of PCMO for Friction Modifiers. There is a lot of good information there. The search function is not great, but, enter Friction Modifiers, in subject, newer than 1 year, older than 6 months, then older than 8 months, then older than 10 months.
Friction modifiers are a low friction, easy shear, first line of defense. Many FM are organic and some older design diesel engines do not like them.
I talked to a Mobil 1 rep and he said M1 5W-40 TDT had a low lever of mild FM.
Quote:
Friction modifiers are a sacrificial, first line of defense, anti wear. Lets take an oil with ZDDP and a good dose of friction modifiers. The phosphorus will attach to the journal and bearing. If the oil film is breached for whatever reason, then phosphorus rubs against phosphorus to protect the bearings and journal. However, phosphorus against phosphorus is a high friction surface. It generates heat and consumes energy/power.
Now the friction modifiers will attach to the phosphorus on the journal and the bearing. I have heard FM describes like fine hair/whiskers. If the film is beginning to breach, you will have FM against FM. They are sacrificial and shear away with very little friction, thus the name friction modifiers. If the breach is severe, then back to phosphorus against phosphorus.
Again, FM are a first line defense, very low friction, generates little heat, consumes little energy/power. Think of them as a near miss protection. I like all the FM I can get in a PCMO.
Obviously, FM would not be good in a motorcycle that also uses the engine oil for the transmission and wet clutch. In my gasoline tractors and small air cooled engines, I use motorcycle oils that have low/no FM. These oils have a very high HTHS, high ZDDP, and these engines run a more or less constant/low RPM. Since I am not even remotely concerned about fuel mileage in these engines, because of the high HTHS, high ZDDP, constant RPM, FM is not a real concern.