It's amazing what an oil change can do

[Quasievil]

I suspect that the biggest reason is that shops want to offer an oil change for a certain price and from that price they want to make the biggest margin that they can. If they use $70 worth of oil instead of $20 worth of oil then they either make $50 less or they have to charge $50 more - lots of customers would balk at paying $50 more for an oil change. If the competition will do an oil change for your customers at $50 less then you will lose some business, to be competitive and still make good money you need to use cheaper oil - so a bike shop will choose a reasonable oil that they can buy for a good price and use that.

If the cheap oil will work fine in your bike and let you run up 240,000 kms on that engine then who cares if you might be able to run up 320,000 kms (or whatever) on Mobil 1?
- Not the bike shop making plenty of money charging you for oil changes and then selling you a new bike, that's for sure.

Yes that, as part of my comment also, it ties in.

Interestingly I have workshops making more margin dollars on a synthetic offer, if they can be arsed offering it, most cant be.

[Banditbandit]

People actually pay mechanics to drain some oil, change a filter and pour some oil in?

Yeah I do ... I spent the 1970s and into the mid-1980s keeping old British bikes running on a very low budget. I sold my small collection and went new BMW and or Japanese because I wanted to be a rider not a mechanic ...

It's not about technical know-how ... I could do it ... but now I just enjoy riding into the shop and saying "fix it .. I'll pick it up after work ..." And yeah ... I do earn in the top tax bracket so paying for it is not an issue ...

[imdying]

Same here... time is money, and they charge less than I earn, and I don't have to get my hands dirty... win win!

I'd rather spend a few hours tinkering with my projects than doing menial tasks.

[cowboyz]

I don't know what average percentage is left in galleries, the pump, the oil cooler, around the cam area, clung to gears, clung to the internals etc etc, but it's definitely more than 100ml in the average IL4, and yes, all 4 stroke motors have three oil capacities listed in their service manuals, dry, with and without filter.

Here's some pics to help you visualise how long and complicated even a bike engines lubrication system is:







Funky shit

all acedemic really... if you take it to a bike shop do they completely drain the oil or not?

Same here... time is money, and they charge less than I earn, and I don't have to get my hands dirty... win win!

I'd rather spend a few hours tinkering with my projects than doing menial tasks.

hey.. if you wondering where you can store all that spare cash.............. my number is ..........

[imdying]

all acedemic really... if you take it to a bike shop do they completely drain the oil or not?

Agreed, not really that important, it's the way it is. Well, unless you pay them half a weeks work to strip the motor and scrub the galleries

hey.. if you wondering where you can store all that spare cash.............. my number is ..........

I'm not rolling in dough, but I do like to spend my spare time doing interesting things, which changing oil, is not.

[SMOKEU]

Agreed, not really that important, it's the way it is. Well, unless you pay them half a weeks work to strip the motor and scrub the galleries

Then there is every chance they will charge you for stripping the engine apart without even taking a single bolt off apart from the sump plug and filter bolt(s), and you'd never know the difference.

[imdying]

Then there is every chance they will charge you for stripping the engine apart without even taking a single bolt off apart from the sump plug and filter bolt(s), and you'd never know the difference.

Maybe you wouldn't, but I'm a bit sharper

[SMOKEU]

Maybe you wouldn't, but I'm a bit sharper

So you reckon you're the sharpest knife in the drawer?

[onearmedbandit]

Even if he was the dullest knife in the drawer, you'd still be a spoon.

[SMOKEU]

Even if he was the dullest knife in the drawer, you'd still be a spoon.

Thanks for the compliment.

[jonbuoy]

I'd be VERY surprised if a proper (class IV or class V) synthetic oil wasn't the best thing to use in a flat tappet race engine - however the additives would need to be right. My understanding is that the most important element for the flat tappet engines oil is Zinc - not enough and they risk failure. Clearly Mobil 1 Racing 4T is formulated for motorcycle engines, not flat tappet race engines - therefore is not the right product for the job. The same base oil with the right mix of additives would most likely work great in the flat tappet engines, though I don't know if such a product exists.

Yeah ZDP thats missing in some cases, I´m still not prepared to risk it in my CB750, not sure I´d put it in a Harley or Buell for that matter, I think Buell actually recommend a "diesel" grade oil in the manual, I´m not too worried about synthetic/mineral argument, the bike had spent all of its life on mineral oil and there was almost no wear internally. I change it more often than most. Better off using a cheap oil and changing it twice as often than using an expensive oil and not changing it at the recommended intervals.

[MarkH]

Yeah ZDP thats missing in some cases, I´m still not prepared to risk it in my CB750, not sure I´d put it in a Harley or Buell for that matter, I think Buell actually recommend a "diesel" grade oil in the manual, I´m not too worried about synthetic/mineral argument, the bike had spent all of its life on mineral oil and there was almost no wear internally. I change it more often than most. Better off using a cheap oil and changing it twice as often than using an expensive oil and not changing it at the recommended intervals.

Surely the ZDP levels are similarly low in mineral oils just as they are in synthetic oils. The reduction in ZDP was done over a decade ago in almost all oils due to the detrimental effects it has on catalytic converters - a 'green' measure if you will. There is nothing wrong with a "diesel" grade oil - Mobil Delvac is pretty good and is a full synthetic oil.

It may be better to use a cheaper oil and change it often enough than a good oil and not change it often enough, but it is surely better to use a good oil and change it often enough. There are many superior properties of synthetic oils that make them better at protecting any engine - regardless of how often it is changed. There is also a ZDP booster product that can be added to oil with low ZDP levels - for the engines that require it.

[jonbuoy]

Surely the ZDP levels are similarly low in mineral oils just as they are in synthetic oils. The reduction in ZDP was done over a decade ago in almost all oils due to the detrimental effects it has on catalytic converters - a 'green' measure if you will. There is nothing wrong with a "diesel" grade oil - Mobil Delvac is pretty good and is a full synthetic oil.

It may be better to use a cheaper oil and change it often enough than a good oil and not change it often enough, but it is surely better to use a good oil and change it often enough. There are many superior properties of synthetic oils that make them better at protecting any engine - regardless of how often it is changed. There is also a ZDP booster product that can be added to oil with low ZDP levels - for the engines that require it.

Where did I say there was anything wrong with Diesel grade oil? My point was (and partly in cheek at starting another synthetic VS mineral oil flame war which most car and bike forums are full of) Mobil 1 may not be the "best stuff" for your particular engine. As I understand it Diesel rated oils have more anti wear additives (modern ZDDP equivalents) than petrol engine rated oils but probably not a good thing to use if you have a CAT.

Better off looking at the manufactures specs and requirements choose the oil that the engine was designed for.

I´m happy running mineral oil in some of my engines but not others. Even some engine part suppliers specify not to use Synthetics in the break in period, some specify not to use it full stop. There reasoning being that synthetic oils can be too slippery, some friction is needed in older engines with flat tappets to allow the lifters to rotate in situ and some only need the friction to be present for the break in period.

http://cranecams.com/?show=faq&id=1

[pritch]

Even some engine part suppliers specify not to use Synthetics in the break in period,

An impressive list of manufacturers fill the engine with synthetic oil at the factory so it's there from new. Those parts suppliers are perhaps a bit behind the play.

[jonbuoy]

An impressive list of manufacturers fill the engine with synthetic oil at the factory so it's there from new. Those parts suppliers are perhaps a bit behind the play.

New engines different valve trains. Synthetic isn´t a problem in newer engine designs. Its only an issue for older flat tappet engines and only over the last few years as the oil manufacturers have been dropping the levels of ZDDP to a level that no longer protects the flat tappets and followers. Its pretty well known problem for re-builders of classic car engines. Google ZDDP classic cars.

http://www.millersoils.net/1_Millers_r_AUTO_ZDDP.htm