Regular oil changes, necessary or waste of money?

[flymo]

Hi all, this provides a small amount of relief to me to post something on a technical subject on this forum for a change. Its been a sad and eventful few days.

Some may know that I run an SV650 race bike. The miles are low obviously but they are certainly manic. I regularly hear from people who race and some that dont, who are in the habit of changing oil and filters every race meeting or more often than the scheduled typical service intervals for road bikes.

Now, I know that it wont likely do any harm to change oil more often than a schedule requires, but is it really necessary? Oil is expensive and I'm a tight bugger at times.

My race bike does maybe 100/150 miles on a race meet, about 10 times a year. I change my oil at the end of a race season and thats that. The bike is warmed before it works hard and gently cooled between races.
I would be interested in your thoughts.

I change my oil every 2500 miles, or every year regardless of miles done, some years I don't get many miles done due to work and stuff.

[Luckypants]

Well regular changes are certainly necessary, but not sure that more frequent than specified by manufacturer are required. Going a little over the interval is not a problem either if using quality oil.

On my DRZ I change the oil more frequently because the received wisdom is the engine is hard on oil. The VFR is about 500 miles overdue a standard 4K mile change.

So do it regular, but don't be anal about it.

[jambo]

In the last 4,000 miles the kwak has done 2 track day events, now I'm not brilliantly fast, but the load on the engine is still pretty high during those days. I felt no need to change the oil ahead of schedule.

I don't race and I'm not a mechanical engineer, but I'd be surprised if a modern oil deteriorated so fast under high load conditions that a relatively low tuned engine such as a mini-twin spec SV ran into lubrication issues after only a single meet.

While conventional wisdom cites regular changes for race bikes I think one reason stems from people looking in the oil after a meet to see if there were any metal shavings or other signs of up-coming doom (blown engines cost championship points, after all).

Longevity is the likely trade off but in an engine that would likely manage 100,000 miles + on the road, and is currently managing less than 1,500 miles a year I think it'd be unlikely to wear out before you stopped using it anyway.

The way to test your theory of course is to send a sample of the used oil at the end of the season to be analysed by a lab. This isn't horrifically expensive and while it may cost more than a fresh batch of oil, it may help you decide on whether you can happily save 9 oil changes with filters per year.

Jambo

Make sure mines done as soon as i bring it out of winter storage every year(beginning of march,ride through til end october only averaging 4/5k miles a year these days)obviously with a new oil filter as well.

[yorkie_chris]

I think the degradation to your oil will be because of condensate with it being left stood rather than through use.

If it is kept in friendly atmosphere with low humidity I think you would be fine to change it every couple of races. I've kept the SV at full chat for 90 miles at a time and generally ridden it like a tool, change oil every 3500 miles. It's not dead yet after 40+k, and my engine is hotter than minitwin tune allows (got some hot cams in it).

Of course there's probably more gearbox wear particles in there from race use than road, but I don't think sufficient to worry about.

[embee]

I'm inclined to agree with the trend of the above posts. A large part of the reason to change oil is contamination of one sort or another, not usually breakdown of the lubrication properties.

If it does get rather hot (semi-synth engine oil is usually OK for around 120C sump temp, we often durability test car engines at 110C coolant + 130C oil sump) you might want to consider a fully synthetic.

I'd use a reputable branded oil of your choice and change it every few meetings, whatever you feel you can justify. You might well be able to source oil in bulk at a bit of a discount, I get stuff from Opie oils , one of the clubs I'm in is listed in their qualifying orgs and I get the 10% discount, but I usually wait for the special offers like "free postage"or "no VAT" which they do occasionally, and do a bit of a bulk buy. The other place to look at is PR Oils , though I haven't used them personally.

As a general guide, it's better to change oil before laying a bike up for winter rather than after, less risk of acids causing corrosion. I confess I don't always get round to it.

Oil every meeting, filter every two. Yeah oil aint cheap however its cheaper than a new engine.

[glang]

Originally Posted by Sideshow#36

Oil every meeting, filter every two. Yeah oil aint cheap however its cheaper than a new engine.

Wot does it look and smell like when it comes out?

Originally Posted by glang

Wot does it look and smell like when it comes out?

OIL!!! Haha,

After a full meeting the oild is somewhere between the caramelly new color and black used oil... slightly toward the darker side of the scale and smells pretty normal to be honest. Usually get a few tiny shards on the magnetic part of the sump plug but nothing to worry about. As I say, I'd rather change the oil every meeting and filter every 2, than have to shell out for a new engine. (£600ish)

My Oil+Filter bill for a year comes to £150, but that is through sponsorship.