I remember many moons ago a product for cars called slick 50. basically an additive to coat the inside of your engine with ptfe,so is this a good idea for a bike with dry clutch ? pros / cons ?
I think it would be risky - who knows where some of that PTFE might end up, and whether it could have strange effects in areas with small clearances. I'm confident that modern oil does a very good job of protecting engine components. I've only once had to have an engine re-bored (and I've run several cars over 100K miles) and that was a Yamaha two-stroke; hardly the sort of efficiently lubricated device that a modern 4-stroke engine is. Even the Castrol GTX of yesterday seemed to allow Japanese 4-stroke engines to get up to very high mileages. It's true that it would be a lower risk with a dry clutch, but why bother anyway?
Way back in the early 80's we experimented with Slick 50 in 2 and 4 strokes and used our Hoffman dyno to verify the results. Now we could only measure BHP & Torque not rate of acceleration that can be measured on todays dynos. The upshot was that it did reduce internal friction and delivered more BHP & Torque. We used it in all of our KDX200 and KX250/500 dirt bikes. I used it in my RZ500LC and it was the fastest one I came across. However back then Slick 50 was used by squirting it down the carb on 2 strokes and a different method was used by mixing it with the oil in 4 strokes. We never saw the same increases on 4 strokes as we did on 2 strokes.=
Slick 50/STP does leave a sticky/slippery coating on engine parts but then so does a good oil, like Motul 300v. I don't know whether it's good or not but seeing that oil companies spend millions developing better oils you would think they might have looked at whatever additives are used in friction reducers and add similar if there were any benefits. Maybe there was more place for them back in the old days before oils were as good? That said I used to work for a company that used industrial sewing machines (these machines had oil in the sump - much like an engine), they started using the new high-speed version of said machines that had separate sump with oil pump and were experiencing excessive wear to the internals due to the speeds involved - we started adding Slick 50 and it made a huge improvement to machine wear...
By that rationale the surest way to introduce Slick 50 to a 4 stroke would be to drip it thru the carb/injector port and avoid the oil bath altogether. Clogging oil pathways is no good at all. I remember having to change all of the external grease on my Ducati. Molybdinum Disulphide Grease (Black Grease) was OK in cold areas but the rear suspension linkage is close to the exhaust. The heat caused a reaction between the Sulphur in the Moly and Steel bearing bush. Result? One seized swingarm bush with extensive pitting (Sulphur + Iron + Heat & Pressure = Iron Pyrites). Never used it again - all grease replaced with Lithium Grease, what a fucking job. Better still on the same subject, add Slick 50 to that cabinet along with those other rare comodities: A tube of Elbow Grease Tin of Steam Bottle of Snake Oil Jar of Blue Smoke
I once put xxtralube friction eliminater in my R1. Of course, I needed a new clutch in less than an hour. D'oh :Banghead:
Isn't that Fools Gold, you were turning your swinging arm into gold, that would play merry hell with the unsprung weight I used to work with Gas Turbines and Sulphur in the fuel was tightly controlled. From my limited knowledge/intellect (delete as applicable) Sulphur combined with vapour (from combustion but atmospheric air would probably do the same) and elevated temperatures the Sulphur and water made H2So4, not good combination for any metal. Could be wrong I was once I used to use Slick 50 many years back, but I agree with @Dukedesmo its no longer necessary, in those days after draining the oil I used to then run flushing oil before a fresh charge, both of which would do more harm than good nowadays
