Synthetic Oils

[BladeBoy]

Do synthetic oils cause clutch slip on older bikes?
What are the do's and don'ts of carb balancing?
Cheers.

[photomike666]

Most bikes have a wet clutch and fully synthetic oil will make it slip to some extent - if you're having troubles try semi-synthetic

As for carn balancing, either use a special gauge or have a work shop do it - don't try and guess.

[mrmina]

Mike's right

[Smitty]

Do synthetic oils cause clutch slip on older bikes?
What are the do's and don'ts of carb balancing?
Cheers.

yes ..generally, not helped as the plates have wear
and the synthetic stuff is too slippery
and carbys?
do buy the right vac guages
do know what you are doing
don't play with the carbs if you don't what you are doing
do take it to a workshop

hth

cheers

[NovaCoder]

I had a thought the other day (it happens sometimes), why don't bikes have a sealed clutch oil reservoir? That way you use super-slippery oil for the gearbox (friction modifiers and all) and some nasty old mineral oil for your clutch.

This approach would also add the benefit of keeping your gearbox oil nice and clean without bits of the clutch plate contaminating it.

[Rusty]

I run a fully synthetic oil in my '84 VF500F with absolutely no dramas whatever. And it hasn't had an easy life.

Some (or most) synthetics formulated for car engines have friction modifiers, which is where you MAY come to grief. If it's a concern, find one without the friction modifiers or use bike oil.

Synthetics formulated for bikes won't make the clutch slip unless it's in bad shape anyway (in which case it'd probably slip with mineral, too), but they cost.

There's no guarantee that the friction modified oil will/will not make your clutch slip, either.

Of course, there's no obligation to use synthetics.

[Tack]

I had a thought the other day (it happens sometimes), why don't bikes have a sealed clutch oil reservoir? That way you use super-slippery oil for the gearbox (friction modifiers and all) and some nasty old mineral oil for your clutch.

This approach would also add the benefit of keeping your gearbox oil nice and clean without bits of the clutch plate contaminating it.

My guess would be that it would get too hot at times and possibly need a seperate oil pump and cooler and/or maybe a reservoir to compensate. Just a guess though.

[Steve_TLS]

There are bikes out there with dry clutches. You hear them rattle on Ducati's. Some BMW's, Moto Guzzi's etc with north south running cranks often use dry clutches too.

I use a full synthetic oil. I've had clutch drama's but don't blame the oil, I tried a dino oil and it still played up. I use synthetic because it helps me to sleep better. I abuse my engine and hope the better shear strength of the synthetic and better resistance to breaking down due to heat, shearing of VI's etc will protect the engine that bit better.

If synthetic really is that much more slippery than dino oil and can cause the clutch to slip, imagine how much better it is for the engine / gearbox, less friction, less heat, more power. You'd be mad not to run syntehtic and just fit some heavy duty clutch springs (But I don't buy the more slippery tales).