Oil Changes and Engine Types - Bikes and Cars

That would be one reason (engine running hotter sometimes). Another might be the relatively small volume of the oil reservoir on a bike versus a car, leading to a quicker build-up of impurities in the oil.

That might have something to do with it, but also there is less oil in a bike. That should mean that contaminants build up faster as the oil degrades. Synthetics claim longer life before problems, but my bike is too to me nice to risk it .

There might be other factors related to the higher rev limits on sportbikes. I have heard good things on Royal Purple synthetic oil when I was changing oil on the fuel pipeline's mainline pumps. The maintenance technician told us that the engineers changed the frequency of oil changes from 4 months to 6 months. Considering these mainline pumps run for days without stopping I was impressed. Other people I have asked said good things about their vehicle oil line tool

Drew

Hmmm...It seems I type too slow to get there first again! Good answer Tornado!

Thanks! The race is on?!

The oil filter is much smaller too.

Another good reason for frequent oil changes.

My old Mini had a wet clutch too, scared me the first oil change when this big glob of goo came out with the magnetic drain plug.

Drew

My understanding is that since most bikes use the same oil to lube the gear box as well as the engine, the shearing of the oil by the gears reduce it's lubricating properties.

Anyone else heard that one?

Im not sure on my answer, but I asked my mechanic the basicly the same question.

Im a truck driver and asked why I change the oil im my truck every 120tkm and every 15tkm in my car and he said, think about the interval, they are roughly a year time span. I´ve been told not to stock up on too much motor oil because of the shelf life.

Maybe it´s a time thing.

Russ

In addition to the reasons already mentioned--higher operating temperature of air cooled engine, smaller sump, same lubricant used in clutch and transmission resulting in additional contamination--add design features. Motorcycle engines are designed for maximum power output rather than longevity; their internal components are subjected to much higher stresses than most automobile engines. (A Ferrari might be an exception to that statement but Ferraris demand special engine oils.) Motorcycle engines need need higher quality oil and more frequent changes to achieve acceptable engine life. Fortunately the absence of catalytic converters allows the refiner to add more ZDDP and other anti-wear additives to motorcycle engine oil. The same logic applies to engines in high performance boats: they scarifice longevity for high output.