The good oil

[kerryg]

I see that the subject of oil has come up before, as you'd expect, but I have a question that doesn't seem to have been covered in earlier threads.

I have a friend with a GSXR1100J Suzuki with a big bore kit, cams etc etc putting out (estimated) around 130~140 rwhp. These are of course oil and air cooled, not water cooled. It's running good quality motorbike specific 10/40 mineral oil now. Given that it's putting out extra HP (and so generating extra heat) and that the oil is also performing a cooling function I wonder whether it would be better to run a semi-synthetic or fully synthetic instead of straight mineral, and would welcome advice from any members with knowledge to share. Recommendations of oil viscosities, brands etc would be great. The engine has 70000kms on it but had all the engine work done about 5000kms ago so. It's a bike for weekend rides and the odd commute and he has no plans to race it so far.

[pete376403]

Oooh, an OIL thread. Could be passionate. Dino versus synthetic, motorcycle versus car, sewing machine oil versus gun oil. (did someone mention guns?)

BTW the oil has ALWAYS been providing a cooling function. Drummed into my head during the apprenticeship - the five functions of oil - cleans, cools, seals, prevents corrosion and lubricates.

[Blakamin]

Oooh, an OIL thread. Could be passionate. Dino versus synthetic, motorcycle versus car, sewing machine oil versus gun oil. (did someone mention guns?)

BTW the oil has ALWAYS been providing a cooling function. Drummed into my head during the apprenticeship - the five functions of oil - cleans, cools, seals, prevents corrosion and lubricates.

Cant wait to hear more... coming up to an oil change meself



mmm
need to know more about the Elbonian Zorch....

[Cajun]

I would stick to mineral or semi, if is running mineral you go to fully synth, it be to thin for it. If he hasn't had any problems with mineral and happy with it stick with it.

And for oil brands i think its really down to personal prefence, for the wifes vtr1000f i put castrol, they sponser honda race bikes, so i put in it nice and simple, in my gsxr600 local suzuki dealer uses shell and also nz suzki team sponsered and use shell so that will do me. Its just something so i always know what brand is gonna go in the bike, always be same brand and same type of oil

[vifferman]

Dunno that you'll get a definitive answer on this. FWIW, this thread got thrashed and rehashed on the US VFR list multitudinous times. There was a guy on there (monicker of "Oil Guy") who used to work for an oil company for a bazillion years, and his advice was that you couldn't beat Mobil Delvac (diesel fleet oil) or Shell Rotella (dunno what it's marketed as here).
Testing I've read indicates that the synthetic and semi-synth degrades a bit less than some mineral oils, but I think the consensus was that mineral oil changed frequently was better value and performance for your buck than more expensive synthetics.
Only thing to stay clear of for your bike is some of the later car oils with 'friction modifiers' (molybdenum compounds etc.) that cause clutch slippage. Mind you on some bikes, the synthetics can do that too. Also on older bikes, the synths can be too skinny and cause leaks or oil burning.
I stick to Motul 5100 15W-50 semi synth, because I like the smell....

[kerryg]

Oooh, an OIL thread. Could be passionate. Dino versus synthetic, motorcycle versus car, sewing machine oil versus gun oil. (did someone mention guns?)

BTW the oil has ALWAYS been providing a cooling function. Drummed into my head during the apprenticeship - the five functions of oil - cleans, cools, seals, prevents corrosion and lubricates.

Hey Pete, fair enough about the cooling function of oil but I guess my point is these SACS engines rely on the oil to cool the engine in a way, and to an extent, that neither the purely air-cooled nor the water-cooled engines did at the time. It might be a complete red herring when it comes to oil selection, but as this bike is generating extra power (and so extra heat) I thought it might be worth throwing into the pot....

[Blakamin]

Dunno that you'll get a definitive answer on this. FWIW, this thread got thrashed and rehashed on the US VFR list multitudinous times. There was a guy on there (monicker of "Oil Guy") who used to work for an oil company for a bazillion years, and his advice was that you couldn't beat Mobil Delvac (diesel fleet oil) or Shell Rotella (dunno what it's marketed as here).

Only thing to stay clear of for your bike is some of the later car oils with 'friction modifiers' (molybdenum compounds etc.) that cause clutch slippage. Mind you on some bikes, the synthetics can do that too. Also on older bikes, the synths can be too skinny and cause leaks or oil burning.
I stick to Motul 5100 15W-50 semi synth, because I like the smell....

that shell stuff is a tractor oil, i think!

I read that theres no diff between later cars oils and bike oils with a wet clutch, it was a myth??????

buggered if i know....just wanna keep my bike happy (cheaply)

[Motu]

eeehh,by gum,an oil thread - better than steering geometry or religion any day.

Yep,oil for heat transfer,it's always doing it,no matter how the motor is cooled,and thinner is better for heat transfer,gets the oil moving around,shifting heat outta one thing and into another.I'm a fan of Silkolene full synthetics,the best you can get I reckon - but in reality any crap will do,just change it as often as possible.

[Lou Girardin]

I've used a few sythetics over the years, in cars and bikes. I think the Mobil Racing 4T offers the best value for money, passes various tests with flying colours and has always felt good in engine/gearbox units, whereas gear shifting deteriorates rapidly with some other brands. Use 10/40 for newer engines or 15/50 if it's got a few miles up.

[geoffm]

THe GSXRs are pretty hard on oil, sqirting it throughjets and stuff, so you want a good oil. Main thing is to change it regularly.
Mobil 1 is recommended for RG500s to do wonders for their crap dragging clutches. Spendy though - you can buy 2x as much mineral oil for the same $$, which would probably give you the same result.
Geoff

[speedpro]

I originally used Castrol R or RS but then went to Mobil 1. The only time I used anything else was "running-in" the turbo and when I pulled it down to check stuff I found the gudgeon pins had a bit of galling. Went back to Mobil 1 and been fine ever since. This in a big old clunky Kawasaki Z1 engine. Mobil 1 was actually reccommended to me by an engineer from another oil company when I was enquiring about what to use in an engine that gets VERY very hot.

[カワサキキド]

firestormer, Give me convenience or give me death or Fresh fruit for rotten vegetables?

[pete376403]

Slick 50!!! Motor-Up!!! (just stirring, now)

Can't beat the smell of Castrol R40 - mmmm, bean oil. It's bloody good lubricant, but forms sticky gummy residue if left for any time. Best for race engines that are pulled apart after each meeting. F*cking expensive, too.

[Motu]

Silkolene,and others I presume,it's just I was on the Silkolene site the other day - do a castor/synthetic mix that solves the gumming issue with castor oil,all the advantages plus the smell! If I had a dedicated race bike I be tempted to use it.

[kerryg]

OK...well now I'm just confused.....................

Here's what I get from the various postings: use any old oil but change it often, mineral or semi-synthetic, use synthetic, use Mobil 1, use Silkolene......geez, I don't know!!! I am thinking in the middle: semi-synthetic, say 15-50 (since older bike with higher kms), reputable dedicated motorcycle oil, changing frequently. That should cover all the bases. What do ya reckon?