I've never used any in my GS. Wondering what effect it might have on the clutch.

Recommendations on good ones?

I've used STP's stuff in cars. Seemed to help.

What problem are you trying to solve with oil additives?  Is there some symptom?

Not really. Just asking about oil additives in general.

I understand some manufactures don't recommend them because they can gunk up your engine.

Some people swear by them.

Quote from: Suzuk-E on August 29, 2007, 10:02:32 AM
Some people swear by them.

I swear at some people.

I would never put junk in my oil.  Ever.  Can't think of one good reason.

Just use good oil and you won't have to worry about additives 

Uhm...okay. So Oil Additives are bad for your engine/clutch? There are no positive results from their use?

Motorcycles use multi grade oil which serves the engine and the clutch ,on autos the clutch is separated from the engine and uses special oil for it .

So if you add some auto additive to motorcycle oil ,which is supposed to reduce friction (a good thing on itws own), you inadvertently hurt the clutch

operation . It could work on Harleys though,they have theirs separated

Most oil additives are snake oil.  There are no positive results from their use.  I find the claims of the "friction reducing" additives really sketchy.  My brother uses that crap in all of his cars.  His cars last half as long as my cars, and they're almost always belching blue smoke at the end of their life.  (My cars usually die because the gas tank has fallen out of the frame due to rust.)

They cost you money.  They likely have plenty of unknown results, in addition to their claimed results, which I don't believe in.

I simply don't see why anyone would do it.

Many people claim improvements from such things.  Look at all the crap on the internet about adding acetone to your gasoline.  It's dumb, but plenty of people actually believe it improved their gas mileage.  It's mostly because when someone wastes money on something or becomes attached to some crackpot idea, they don't want to admit they were wrong.

Most likely an oil additive will improve performance by lightening your wallet.  Many of them will not do anything bad to your engine, so if you want to use them, fine.  If you try something and it makes your clutch crappy, then you just have to change your oil early.  So go ahead and try it if you want.  I just don't like the idea of giving those people money.

I've seen that some people on here have added Seafoam to their oil before doing a change.  I wonder if it will damage the clutch discs at all?

John

So how did STP help in your car??? and what are you expecting it to do in your bike???.
We are getting back to the synth`oil and the magnets-on-the-fule line issue. Its the placebo-effect. You convince yourself that it will do some good and therefore you convince yourself that it is doing some good. The GS engine is 30+yrs old, air-cooled, OHV, with titanic clearances, regular oil and filter changes with good quality oil are all that is needed to keep it sweet. The additives over here like Slick-50 for example contain PTFE and that is something I wouldnt let anywhere near a wet-clutch.
Save the money and put it towards something benificial like new brake pads or  tyres.

Seemed to just run smoother...at least immediately after I added it. lol

Why is there no mention of specific "motorcycle oil" in the manual. just says use "SAE 10w/40". 

Look at a 'new' car. Does the manufacturer recommend using blah oil additive to prolong engine life ?

If they do, run, don't walk from the dealer. They're shafting you (already knew that) and they're getting a kickback from whoever supplies the oil additive.

No, oil additives aren't needed. Car makers don't put it in, because it would be an uneeded expense. The wife's Honda owners manual even states very plainly:

"The use of oil or gasoline additives are an unnecessary expense and only increase the operating cost of running your vehicle." <--- that's as direct a quote as I can recall.

IIRC my toyota's manual says the same thing.

Suzuki-E?
Car engines are not the same as bike engines. Cars dont have, the Oil shared between engine and transmission, wet clutches and Sprag type starter clutches. Motorcycle specific oils are designed to cope with these differences and any additives containing friction reducing materials like PTFE and Moly-bendium will in time have an adverse effect on the clutch and the starter-sprag which depend on a degree of friction to operate correctly.

My manual states 10w/40 API SE or SF, the SE/SF means its make-up is suitable for use in motocycles with wet clutches. SE was current when the GS was launched but is now obselete. Instead you will see API SF/SG/SH any of which is suitable.

Thanks for the info all.

Quote from: sledge on August 29, 2007, 04:40:09 PM
regular oil and filter changes with good quality oil are all that is needed to keep it sweet.

Haha, I don't even use quality oil.  I use buck-a-quart walmart crap, and it's great.  I have two bikes, two kids, and a six month riding season, which means I can BARELY get 2000 miles on each bike before their annual oil change.

I do put Sea Foam gas/oil additive into the fuel and my oil. Mostly to remove possible water condensation and promote deposits cleaning. Sea Foam is one of the additives many on this board like a lot (from experience).

I did read a lot before starting using it. Does it really work? I dunno' frankly. Google it and you'll see some positive reviews (like http://www.webbikeworld.com/sea-foam/)

It's about $7 at AutoZone/Pep Boys/etc.

Seafoam..... Berryman's.........basically the same.  No benefit from introducing it to your oil.......in fact I'd suspect it could cause damage to the clutch.   A little in the gas tank with a carb'd gravity fed system from a metal tank will help to clear out any  MINOR deposits of rust and silt............not a substitute for properly cleaning and sealing your tank and cleaning your carbs.   I wouldn't use it after kreeming or POR-15 ing a tank though,  not sure what it would do......

Is there any documentation from the manufacturer that says to use "motorcycle oil" rather than regular car oil?

My GSXR600K7 manual says specifically not to use oil that is branded energy conserving.  Basically car oil.

Quote from: NWDave on September 01, 2007, 11:43:09 PM
My GSXR600K7 manual says specifically not to use oil that is branded energy conserving.  Basically car oil.

car oil != energy conserving.. it will specifically say energy conserving..