A very slippery subject - Which oil..???

[manyrevs]

The model of bike is probably not that important (it's a VTR1000 anyway) but I am not that impressed with the Motul 5100 which is currently in it. As soon I put this oil in I immediately noticed an average of about 3 degrees jump in temperature at normal highway speeds and as soon as I slow down in traffic, like on that friggin motorway at 5:30pm (crawling speed) the temperature seems to go up a lot faster than it used to and you can also notice a few rattles and noises from within the engine. I have noticed this with Motul oil in previous bikes but I couldn't see any better oil to get while I was at the shop, so Motul it was. I have also heard comments from others about this oil. I have done a few thousand K's on it now and am about to go to something else - But What..??? Preferably 20 - 50 weight..!!!

Any preferences... Any opinions...???

[FilthyLuka]

why 20-50? its a bit chunky for a new bike init?
i know my brothers runnin castrol gtx 15-40 in his 92 fireblade. no complaints. the bike shifts fine and doesnt get hot as fast as you say yours does

denden

[MSTRS:Me]

I use Shell Advance SX4 semi-synthetic (15-50) in all our bikes. Seems to be fine in all situations.

[TLDV8]

I am running Motul at the moment and have noticed the temp thing also (83/84C) The problem with TL's is if the temp goes to 80C it switchs to the cold start map and runs rich.
The worst oil i have used Plutoline (instant notchy gearshift)...The best but i couldn't find any was Maxima in the gold container 15/40 ?( quiet engine,smooth gearshift)

Nothing like straight 50 weight (GP50) in old Ducati's.

[manyrevs]

why 20-50? its a bit chunky for a new bike init?
i know my brothers runnin castrol gtx 15-40 in his 92 fireblade.
********************************

I always use 20-50 as the safety margin in oils. Antyhing oustide these limits is not really necessary as New Zealand doesn't have teperature extremes enough to justify using them. 20-50 any day over 10-40 for me.

Forgive me for saying this but Castrol GTX is an oil primarily made for the average car engine and would not come under anywhere near the same torture as in a high revving bike engine. For average use, it may not suffer at all but under high speed/revs, I doubt if it would be the best choice. Having said that, oils have come a long way and you may find that GTX is suitable for some bikes... I will go for an oil specifically designed for bike engines...

[Motu]

Thinner oils transfer heat faster,they also make more HP on the dyno.What is getting hotter - the coolant or the oil? Is there an oilcooler? Maybe the oil is actualy better at transfering heat and putting it into a different place....which you see as an increase in temp....it may not be a bad thing.

[Blackbird]

Have had Motul 5100 in the Blackbird for around 4 years and that's a hot-running bike in traffic. I switched from Mobil 1 4T as Honda actually recommend semi-synthetic over a full synthetic

I agree with Motu and recommend that you stick with Motul.

Geoff

[manyrevs]

Thinner oils transfer heat faster,they also make more HP on the dyno.What is getting hotter - the coolant or the oil? Is there an oilcooler? Maybe the oil is actualy better at transfering heat and putting it into a different place....which you see as an increase in temp....it may not be a bad thing.

While I can semi agree with you about the thinner oil, you have to remember that the less drag an oil has, the less heat will be created by rubbing parts and the more efficiently moving parts can transfer their stored energy onto the final destination - pistons/conrods/crank to gearbox etc... A blanket statement like "thinner oils transfer heat and produce more HP etc" is far from the truth in ALL cases... The ultimate oil would be one that has literally no drag at all and has the ability to stay where it belongs, no matter how thick/thin it is, but no such oil exists... The only reason it may appear to give more HP on a dyno would be that there is less of the "thin oil" between mating surfaces, temporarily creating less drag but as the engine spins faster, it would create heat as the less oil between surfaces also gives less resistance to grinding, causing more heat, causing more grinding and so on, eventually spiralling out of control...

Nowadays, the additives in oil are better at friction control/slip and heat transfer than the oil itself. The oil more or less serves only as a body to hold them in and to get them into all those little out of the way places... Oil also carries away all the burnt crap which sneaks past the rings and any other bits that slowly grind away...

It's be so long sonce I bought any oil for a bike that I have forgotten what is around, so I am asking you guys for advice...

[Flyingpony]

I'm running Castrol R4 Superbike fully-synthetic SAE 5W-40 oil (link). The bike runs much nicer on this stuff than it did on Shell Advance semi-synthetic SAE 15w-50 oil.

Improvements noticed are:

• Quieter operating noise
• Lighter gear shifts
• Virtually eliminated gear shift grinding
• Very noticeable improvement in fuel economy

[bane]

i put Castrol GPS in all my bikes - 10W-40 semi synthetic.

seems to be a good compromise.

[DEATH_INC.]

I'm using Castrol gps at the moment, though only because of my budget (I can get it through work) it seems to be ok.
I prefer Rock Oil, or Silkolene semi synth.
I flat refuse to use Motul, I'd rather use water.

[manyrevs]

I wound up getting Motul 5100 "again"...
Why..???

Bacause no matter where I went to get either Castrol or Mobil motorcycle oils, I got...
1. No we don't stock those oils...
2. Ahhh.. What sort of oil was that again..???
3. Looks like we just ran out of that...
4. Ahhh.. What sort of oil was that again..???
5. We only have oils for cars...
6. Ahhh.. What sort of oil was that again..???

I spent up to 3 days phoning all around the local district (Sth Auck) only to be confronted by younger guys who thought they knew everything about engine oils but didn't know why you can't go using any old oil in a bike engine...
1. Whatdya mean a wet clutch...
2. Fully synthetic what..???

These were guys who worked in shops like Supercheap Auto and Repco etc because they stock the particular brands I was after, but I simply gave up in the end and went back to the Motul brand. Who cares about a few noises, as long as it's doing its job... I found out that Cycletreads have one of the oils I wanted to try but I couldn't get over there in the Pre-Xmas mayhem so I went to the local bike shop and threw them a few bucks...

Maybe next time...