Oil question

[Dougie]

Okay I've probably asked this before,but as I is getting on a bit I'll have forgotten.....
The GS is near 30 years old with mebbe 110000 to 115000 miles on the clock.For years I've been using 10w40 (or 15w40),not bike specific,with no problems like clutch slip as that's what it sez on the filler cap.The Haynes book of lies sez to use 20w50.
So,what's best for a bike of that age and mileage?Something like Duckhams?I know to avoid fully synth like the plague cos it'll leak like a bastard (apart from the cost :rolleyes: ).

[dracken1]

duckams will be ideal for a bike of that age. might be worth avoiding 20/50 as the extra viscosity when cold could cause it to flow to slow through the oil ways when it gets cold up north :)

[Dougie]

Cheeky bugger,it's warmer here than you think!
Seriously tho',ta Dracken. :D

[John Hopkins]

Now I have always used 20w50 mineral oil on bikes with a large bore, 250cc per pot or more and 10w40 mineral oil on bikes under 200cc per bore, as the additive in synth and semi synth contains teflon and silicon I figured it could contribute to clutch slippage, thats why I choose ordinary mineral oil..I usually stick to the same brand between £7 and £8 per gallon...I keep my bikes in a garage and give them a few minutes at tickover, until the choke goes in, before riding off, and I justify the 20w50 because on an older bike it pads the engine when hot and is really quite thin when cold, also It is the engine temp, not the wind temp that the oil sees...But Dracken1 is a professional and I am not...My bikes are 16 and 18 years old..John

[dracken1]

you don't know how warm i can think!

at present i'm thinking warmer than we ever get it it this bloody country :D

[trikerdrew]

but then again I'm a mucky sod :D

drew

ps

10/40 or 20/50 depends what the best deal is.Changed every 3 thou.

[Creature]

i always use castrol gtx magantec for older engines

[johnr]

ive always used the old duckhams green slime20/50 or castrol gtx, but not the magnatec, i was told that it wasnt reccomended for wet clutches.

[gothtec]

This is an issue that I've been having as well, but on my 3 year old dragstar.

Could I use Adsa cheap as chips motor oil instead of the overpriced specaily formulated motorcycle oil?

If so what issues will the engine have (and an already slipping since new clutch system)?

[Dougie]

Most supermarket oils are made by Esso,so as long as it's got a good rating (SH and above) you should be okay.DO NOT use anything marked "Energy Saving" as that WILL make yer clutch slip.
I've been using supermarket oils for years,100000 odd miles and one rebore.As long as you change it and the filter regularly you should have no probs.
I just wanted to know if 20w50 would be more suitable for my old beast in its advanced years......

[pyro]

Older bikes will quite happily run on 20/50, just let it warm up for at least 2 minutes before riding, this gives it time to flow into all the oilways.

It is a good idea to let any bike warm up before riding anyway.