Friction mod & racing: anyone NOT had probs?

[GrahamB]

Ok, I've read the "Oil X made my clutch slip, from now on I'm only running dino oil" threads. Well enough of them anyway

. Similarly with the "does oil X have friction modifiers or not" threads.

So let's try something different: has anybody used oil which DOES claim to have friction modifiers, in a wet clutch application subject to high load (ie road racing is my particular interest) and had NO problems?

Background: I'm racing a GSXR600 supersport bike: kit cams, kit ignition, redline now at a genuine 15,500rpm. I've been running M1 motorcycle specific 15w50 (no typo, that's what we get in Australia, MX4T doesn't seem to be available now).
I'd like to try a lower visc. oil but baulk at the price of Motul 300V. So it would be nice to try one of the full synth 5w40 etc car oils: Motul 8100, M1 car oils etc. Yes, there are other options (Silkolene, R4 superbike, Amsoil) but are they necessary?

Please, I'm not interested in "It won't work", I'd like either "we tried & had no probs" or "we put it in a modern, well maintained race bike and had the following issues"

Thanks heaps,
Graham

 

[GrahamB]

Ok, replying to one's own posts is bad form...

Just did a little experiment. My SV650 road bike needed an oil change. It has almost the same rear wheel torque as my GSXR (45ft-lbs) and slightly lower primary gearing (2.088 vs 1.96) so the clutch should be loaded about the same. I drained the old oil (I just bought the bike used, no idea what was in it but it smelt dead dino), replaced the filter and re-filled with Motul 8100 excess 5w40. This has friction modifiers according to Motul.com, has diesel certs but is targeted at "all MB motors".

Then I went out and abused the clutch as much as I could: rolled up to max torque rpm and whacked the throttle wide open on various steep hills. I even tried a hard-ish start in 2nd gear.

Not a slip, not a whimper. Clutch take-up was perfectly smooth. Maybe it takes time for the FM's to bind onto the clutch plates?

 

[penzdude]

graham, while not a racer, i have a good bud who rides a honda sabre cruiser. he always seems to have his,er, somewhat large, wife on the back. has soft bags loaded to the hilt too. he refuses to buy anything but pennzoil 10w40 car oil. i'm not sure about the new formula, but the older one had lots of moly in it. he has a wet clutch, and never ever gets any clutch slippage. he rides hard too. says that the mc specific oils are a scam. dunno. you hear "never had a problem" to "made by clutch slip like crazy". the weird thing is, that some people have clutch slippage issues even while using the mc oil. can't win for losing. it seems like wet clutches have been around alot longer than all these mc specific oils too. i'm sure most racers though, have some sort of support, and probably get the oil for either free or at a reduced rate, so i'm sure the $$$castrol superbike oil and the like are the norm.

[ January 09, 2005, 10:18 AM: Message edited by: penzdude ]

 

[KW]

I had no problems with clutch slip on a Suzuki Bandit drag bike with Mobil 1 5W30/10W30 oils. The stock clutch springs are known to be weak and even a stock motor could push past the clutch with any oil. All the clutch needed was a good set of springs and I was set. The thin M1 made the bike rev faster and I even gained a little on my ET's.

I all comes down to a little trial and error to see what your clutch pack can handle.

 

[Motorbike]

quote:

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Originally posted by GrahamB:


Please, I'm not interested in "It won't work", I'd like either "we tried & had no probs" or "we put it in a modern, well maintained race bike and had the following issues"

---

With some real world experience maybe this will help you to some extent .

Long time bestest friend , riding and racing buddy # 711 picked up a 1992 CBR F2 around 2002 with like , 8k miles on it to replace his old bike , a 1991 model .

At the Kansas track in 03 he was having hard time with one Buell that had some drive on him out of the corners and onto the straight. He switched to Mobil 5w-30 Supersyn to gain some power in 2003 and stuck with it . He races several classes and the bike gets more race miles per season than most in the CMRA because of it . The clutch plates are OEM Honda , I can tell you no more other than the motor is down and apart for re-fresh after all those street miles then two seasons of racing and everything looks good and camshafts will be re-used .

I do think the motor will be using a much better 30wt car/racing oil this coming season .

Oh yeah , the clutch don't slip

 

[satterfi]

Redline 10w40 works fine in GSXR 1K's.