Oooh, look, another oil thread....

[throttlemeister]

Well, my bike doesn't sit still for 3 months at a time and it doesn't get used to poodle around for short bits in town either.

Synth does not make a bike use more oil. What can happen is that the 15W50 is too thin when cold, causing more use when starting and running untill it is hot. Going back to 20W50 will solve this.

What also can happen with an older bike that has been running dyno oil for years, that synth dissolves the deposits left by the dyno oil. If certain engine parts have worn out, like valve stems, these deposits can keep it from burning oil for a while. The cleaning of the synth will remove the deposits and it will start using oil. Going back to dyno will have no effect at all, as the deposits are already gone and it will keep using oil untill the defective parts have been replaced. Which makes it a bad idea to put synth in an older higher mileage bike that has always been running dyno.

My S uses oil, as does just about every boxer. Experimenting showed the type of oil does not change this. What does change this is for instance heavy engine braking in the mountains. Oil consumption will jump. Leaving the mountains and/or less engine braking will reduce oil consumption to normal levels. This is caused by the huge vacuum created by the cylinders on closed throttle, sucking oil past the piston rings into the cylinder.

But by far, typically the most oil 'use' in a boxer is the blowback into the airbox.

My bikes get fresh oil every 12,000km and not a second sooner. Shit, even my old 1974 CB400F got that treatment, and it had 120,000km on the dial by the time I totalled it.

Of course if you do a lot of short rides and the engine doesn't always get to operating temps, it is wise to change oil more often. If you use your bike normally, it is perfectly ok to change later. If you only do long distances, it is just plain silly to not to. My VFR ran Motul 300V esther based full synth, and it got changed every 16,000km. I sold it with 52,000km on the dial and it never used a drop of oil or did anything other then run perfectly.

Do as you wish and makes you happy but please don't kid yourselves. These modern engines are spec'd to the point of dealing with severe abuse and still survive. If the spec is 8,000 miles, it is not going to fail at 8,100. You are likely to be able to run it for 10k more with the cheapest oil you can get without experiencing any immediate ill effects. There are margins builtin, and those not built on the best oil you can get but rather the most common, cheap oil you can get.

[madman]

I am still using synthetic in both bikes, one with 28K miles and one with 9k miles. They do not use much oil and I check every time we go out. I would guess that I top up about half a sight glass ever 1500 miles.
Both bikes now have 5W50 in them. I would not put 20W50 in them because as an engineer, I could not stand the wear on startup.
In the heat I know that a synthetic is protecting more than a mineral due to the long chain molecules and the fact that a mineral suffers from additive breakdown at excessive temperatures.
Apart from that with synthetic at less than £12 for 5 liters here, it is not worth going back to an old design of oil.

[oyster]

Great thoughts on oil above. I had been changing my Lidl mineral oil every 3000 miles. Currently using some Comma mineral. The detergent issue is one I had not thought about. Perhaps I'll leave the changes to 4000 miles now. If the semi synthetic was cheaper, I would use that, seems to offer the best of both worlds.
I recently changed the gearbox & diff for the Mobil fully synthetic that Joe sorted out. Each one made a noticable ride difference, the gearbox became so slick that I missed fully selecting gears for the first time. Soon got used to it though. All was smoother. I had been running fresh but budget gear oil in both.
As for changing the oil before or after dyno testing, I know my bike got very hot, so had to leave it to cool a couple of times. That dyno had two large air vents blowing '70 MPH' outdoor air onto the motor. My thought would be to change the oil after. Make sure it's up to the level before.

[madman]

If you are thinking that the dyno will let the bike run too hot, then it may cook a mineral oil and start breaking down the additives. In that case you would be better changing the oil, not just the filter, after the run.

[sproggy]

Thanks - changing the oil after the run was what I was tending towards. Good to hear that other people agree!

I can't wait to get my S back on the road - 4 months since I rode it and I'm suffering severe withdrawl symptoms - a Transalp is not a worthy replacement.

[crucial]

Well here's my 2p worth

People worry too much about oil. I change mine every 6k miles (or there abouts). She's had a diet of Mobil 1 (cheap in Costco), Halford's finest own brand and just about everything else at one time or another. Still uses pretty much the same amount at 110k miles as she always has.

How many miles are you expecting your engine to run for?

[Cobbster]

I agree with CRUCIAL, but!!! since changing my oil to 20/50 weight, tick over at start up is a bit laboured thus the bike tends to rattle and squeek from places that it didn't on 10/40. As soon as you pull away and youv'e warmed the oil a bit its back to its old self.

No big worries but doe's anyone have any thoughts on this one?.

Cobbster.

[jltownshend]

http://www.boxertrix.com/phpBB2/viewtop ... 36&start=0


Zzzz....

More important:

If you have semi, does anything much happen if you top up with mineral, or vice versa (or with fully synth, etc).

Could we, indeed should we, mix our own oil and sell it under the Boxertrix label?

[Stevie]

....

Could we, indeed should we, mix our own oil and sell it under the Boxertrix label?

Ha! the problem with that is that you would need as many different variants as there are Trixters!

[madman]

I agree with CRUCIAL, but!!! since changing my oil to 20/50 weight, tick over at start up is a bit laboured thus the bike tends to rattle and squeek from places that it didn't on 10/40. As soon as you pull away and youv'e warmed the oil a bit its back to its old self.

No big worries but doe's anyone have any thoughts on this one?.

Cobbster.

Yes, that is because the 20 bit is very thick compared to a 10 or a 5 and will take much longer to reach the bits furthest away from the oil pump. It will also put more of a strain on that oil pump. Even though it is a lower number than the 50, the oil is very much thicker at a cold 20 than a warm 50..

[SVA]

I accidently ran my R1100S below the MIN mark . I prefilled the engine to just below the MAX indication, with the engine being cold. After a ride, the indicater was just above the MAX indication. Another

But now... after just 30 km and a cold engine the oil is a little above the middle.

I am measuring the oil using the center stand(on approx level ground), and there is 10W40 oil on the bike.

Am I F'cked?

[Cobbster]

Hi SVA,

These bikes hide oil like no other. If you take it on a decent run to get things nice and hot, then check it on level ground it will probably make a return back to the sight glass. My bikes level was just below the max last night, I took it to put petrol in, approx 4 mile run, got back and its half way down. Checked it this morning and its back to the original level. I think its got something to do with the oil cooler holding it in until the engines nice and hot and all solenoids are open allowing a free flow around the system.

Cheers Cobbster.

[SVA]

I actually just returned from driving a 7-8 km drive. I checked before I started the engine, and it was just above half. After the run it was a little above. After moving the bike from side to side, it was up on max again. pheeew. But thanks! This site is really great for me as a total newbie:)

[sproggy]

I think its got something to do with the oil cooler holding it in until the engines nice and hot and all solenoids are open allowing a free flow around the system.

Solenoids? There's an oil thermostat and if it's closed (engine cold or not fully warmed up) it'll restrict oil flow back to the sump when the engine's switched off. But if left overnight in most cases the oil will find its way back gradually.

If you get the bike fully up to temperature on a run and then park it in the garage the oil thermostat will still be open so the oil will drain back pretty quickly.

So the answer is to check the oil after a run that's warmed the bike up fully - not when cold and not when slightly warm after a short run.

[Cobbster]

SOLENOIDS???
Sorry brainstorming moment, thermostats!!

Cheers Cobbster.