When To Switch to Semi Engine Oil

JoeC

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Bought bike (1150 '02') with 6.5K miles on the clock a year ago and it is now on 16K. I have used mineral oil in it since (2 oil changes so far with mineral oil) but would you advise now going to semi?
Unknown service history prior to me getting it so have been running the engine in since and servicing bike myself.

Also, should you use mineral or semi oil (GL5) in gearbox/final drive? I did a change when I got it and put in semi.

Don't want to drag out the 'oil' debate but a few quick pointers would be great.

Ta
Joe
 
I used semi synthetic for a short while a few years ago.. the engine was noticeably noisier, especially in warmer climates, changed back to my regular Duckhams 20/50, no further problems, can't see the point of semi synth. in a low tech engine such as the 1150 boxer.. mine didn't like it at all.
 
Mineral in the engine for ever.. I dont see the point in messing around. spending more money than necessary for no real gain. tried semi in the past and there was no difference. I spoil the engine by changing the oil anywhere between 3 an 5,000 miles. (and pay £8.50 for a 5L tub) nothing fancy - these understressed tractors don't need it.

GB & FD Halfords Gear oil part synth 75w/90 GL5 £9.99 a litre. I do both at the same time. every 12,000 miles. (or yearly)
 
motobiker said:
GB & FD Halfords Gear oil part synth 75w/90 GL5 £9.99 a litre. I do both at the same time. every 12,000 miles. (or yearly)
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Halfords also sell mineral 80w90 GL5 Gear Oil (labelled as differential oil) - has improved my gear change compared to their 75w90 I used previously.
 
I never noticed that. The crucial thing for me was that it says GL5 and the 'weight' was roughly correct. I'll have a look next time - still got a full bottle of semi waiting to go in at the next fluids change in the next month or so.

I dont seem to have as clunky a change on this bike as I had on the previous one. (a 96)
 
Quote from the 'Engine Oil Bible':
If you do decide to change, only go up the scale. If you've been running around on synthetic, don't change down to a mineral-based oil - your engine might not be able to cope with the degradation in lubrication. Consequently, if you've been using mineral oil, try a semi or a full synthetic oil. By degradation, I'm speaking of the wear tolerances that an engine develops based on the oil that it's using. Thicker mineral oils mean thicker layers of oil coating the moving parts (by microns though). Switching to a thinner synthetic oil can cause piston rings to leak and in some very rare cases, piston slap or crank vibration.
Click to expand...

Degradation in lubrication? What a load of shite. What sort of engineer wrote this rubbish? Crank vibration? What the feck is he talking about?

Engine Oil Bible said:
Using Diesel oil for flushing

A question came up some time ago about using diesel-rated oils to flush out petrol engines. The idea was that because of the higher detergent levels in diesel engine oil, it might be a good cleaner / flusher for a non-diesel engine. Well most of the diesel oil specification oils can be used in old petrol engines for cleaning, but you want to use a low specification oil to ensure that you do not over clean your engine and lose compression for example.
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"....over clean your engine and lose compression..." Are you serious??? How the feck can oil do this?

Utter load of meaningless nonsense.
 
Semi Synthetic Oil in an 1150?

Be like pouring Remy Martin VSOP down a shaking gibbering alchy's throat hoping it'll make him speak more coherently :thumb2
 
....and there's more...
Engine Oil Bible said:
Larger filters on standard cars?

There's a school of thought which says that enlarging the oil filter on your car is A Good Thing. Why is this?
The small oil filters fitted to engines these days run with quite a high back pressure, and the bypass valve trips at about 3500rpm. That means that your oil is not being filtered when the engine is spinning faster than 3500rpm. As the oil filter does its job and starts to clog up, that rpm value can be lower.
If you increase the size of the filter, this will raise the rpm at which the bypass valve will switch. With a bigger filter and lower back pressure, for the same rpm (prior to bypass valve operation) less engine power will be lost in the filter. Bigger filter means better filtering and more power at low to mid revs. Clever eh? But there's some things you need to be aware of if you're going to try this approach, all of which are relevant, and none of which I can confirm or deny
Click to expand...

So - at anything over 3500rpm, your oil is not being filtered. What fekking planet is this bloke on? Utter load of drivel.
 
....and another absolute beauty...
Engine Oil Bible said:
...So I owned a 2001 BMW R1150GS motorbike. I bought it pre-owned from my local dealer who assured me it had been through the workshops as part of the "standard procedure" of them taking a bike in and re-selling it. For 2 years I'd been riding it with horrible engine noise and engine detonation (pre-ignition). Every time I took it back to the dealer, they were adamant there was nothing wrong with the engine, and that "they all do that". Not believing them, I finally found an independent BMW specialist who took the engine apart for me. It turned out the BMW dealership had lied - the bike had never been in their service department. This was evidenced by the fact that the cylinders had sand in them. The dealership had never bothered to check the bike and wouldn't believe my complaints about the noisy engine. The independent mechanic fixed it all up for me - an $1100 repair bill that involved basically stripping down the entire engine, honing the cylinder barrels, putting in new piston rings, cleaning the pistons, barrels, heads, throttle and airbox, flushing and cleaning the whole thing and putting it all back together. The point is that during the two years I'd been riding it with sand in the engine, I'd been religiously topping up the oil and changing the filter. It's a testament to BMW engineering that the engine ran without seizing up, but it's also a testament to paying attention to your oil changes. If I'd let it slide, or not done the filter, that engine would not have been a rebuild - it would have been a far more costly brand new engine.
Click to expand...

"The cylinders had sand in them...." Sand? Are you serious, man? It would disappear within several seconds of the engine running. It would certainly not be evident after thousands of miles. Fukkwit.
 
I started to read it but felt my eyes start to glaze over and the beginnings of a death wish.
 
I guess you guys were not impressed then? :mmmm

Since I do not know better I pretty much take it as read, sorry for the obvious upset/loss of sleep caused.

Chris
 
gbmud said:
I guess you guys were not impressed then? :mmmm

Since I do not know better I pretty much take it as read, sorry for the obvious upset/loss of sleep caused.

Chris
Click to expand...

Don't fret about it chap. A lot of stuff that comes out of america is full of useless nonsense. There was some good info on that page - but also a load of total rubbish. Thats how it is with a lot of stuff from over there.

Calling it a "bible" was spot on though... but I guess it wasn't named such out of irony.. the americans dont understand the concept. bless em.
 
A friend of mine with an 1150 with about 50K on the clock switched from semi to mineral to save a bit of money buying the oil. However, he found that his engine started to burn oil with mineral in it. He switched back to semi and it does not burn oil anymore.
 
Nippy Normans supply Touratech, Wunderlich, Desert Fox and many other makes of accessories.
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