8k miles between oil changes?

[RVFRick]

My last oil change was 4k miles ago so I figured I was overdue for another. It turns out the 1990 Honda CB-1 service manual recommends oil changes at 8k mile intervals. Does that sound excessive for a high strung 13.5k rpm redline engine with a wet clutch? No trackdays just weekend twisty stuff.

EDIT: Bear in mind the manual was written based upon oils available in 1989. Not sure lube technology has changed in 30 years as significantly as marketeers would have us think but I'm not an expert.

 

[dtrides]

I would change it.
You can send a sample out and have it analyzed and they can tell you exactly what shape it is in .
From my experience the gear shear breaks down even good oil much sooner than 8K.
I typically change oil on my road bikes 3-4 K when using a good full synthetic oil, sooner using standard oil.
DT

 

[RVFRick]

I would change it.
You can send a sample out and have it analyzed and they can tell you exactly what shape it is in .
From my experience the gear shear breaks down even good oil much sooner than 8K.
I typically change oil on my road bikes 3-4 K when using a good full synthetic oil, sooner using standard oil.
DT

Interesting. Google result led me to Blackstone Labs - charges $28 to analyze an oil sample.
What is gear shear?
What method or metric did you use to identify break down? For that matter what's your definition of oil break down?

 

[mototireguy]

Maybe with full synthetic oil can go 8k. Would be interesting to see what used oil analysis says about a sample of full synth oil run out to 8k miles.

And depends on the bike. Some bikes shed more/less wet clutch material, combustion blow-by, other byproduct contaminants into the oil than others.

 

[MapleRoad]

Interesting. Google result led me to Blackstone Labs - charges $28 to analyze an oil sample.
What is gear shear?
What method or metric did you use to identify break down? For that matter what's your definition of oil break down?

Blackstone Labs does an excellent job of analyzing your oil condition. The report is more than just numbers. It is money well spent. If you're looking to verify that the oil is still OK at the end of 8000 miles, it would be of value to get the TBN as well. it's another $10, but will give you the peace of mind that your engine isn't getting ruined by an 8k interval.

 

[Pushrod]

$4.50 for bottled water, $6.50 for a beer at the game, $5.75 for coffee at bux and energy drinks at $3.00 all of which you piss out in less than an hour. . . .letting an oil change go to 8K miles, priceless.

 

[GB500guy]

Rick, for comparison my other 1989 bikes specify a 4K interval (GB500) and 8K interval (NX250 & CB-1). Shorter interval for the air cooled GB I guess. But I always just change them all at ~2K miles, filter every other time. Oil's cheap and easy to change.

-Bill

 

[ScottRNelson]

KTM is recommending 9000 miles between oil changes on my 2018 1090 R.

I'll probably change the oil based on time rather than mileage, since I split riding evenly between my two bikes and don't manage 9000 a year currently.

 

[Gary856]

Ducati manual says 7.5k-mile oil change interval for my '13 Multistrada. With full synthetic and the relaxed way I use the engine I think a 5.5k-mile change interval gives plenty of margin. Waste is waste regardless of cost.

 

[ST Guy]

With quality full synthetic, 8000 is fine. I used to change the oil on my ST about every 10-12,000. After 80,000+ miles, compression is 180ish.

 

[Busy Little Shop]

Your oils wear protection capability is determined by the 90% base oil and its
10% additive package which contains the extreme pressure components... when
the 10% additive package is used up your oils only protection is the 90% base...

Manufactures actually test oils in their engines to determine the longevity of the
additive package... if enough additives exist at 8K the manufactures states that
finding in the manual... if you wish to know for sure what percentile of your oil's
additives exist at 8K then send a sample to Blackstone Labs and pay extra to
know the TBN (Total Base Numbers) numbers...

Total Base Numbers or the percentile of the additive package of oils where 2 is
low and 12 is high and 10 is average...

 

[ST Guy]

Your oils wear protection capability is determined by the 90% base oil and its
10% additive package which contains the extreme pressure components... when
the 10% additive package is used up your oils only protection is the 90% base...

Manufactures actually test oils in their engines to determine the longevity of the
additive package... if enough additives exist at 8K the manufactures states that
finding in the manual... if you wish to know for sure what percentile of your oil's
additives exist at 8K then send a sample to Blackstone Labs and pay extra to
know the TBN (Total Base Numbers) numbers...

Total Base Numbers or the percentile of the additive package of oils where 2 is
low and 12 is high and 10 is average...

Any idea where Redline fits in there?

 

[dtrides]

Interesting. Google result led me to Blackstone Labs - charges $28 to analyze an oil sample.
What is gear shear?
What method or metric did you use to identify break down? For that matter what's your definition of oil break down?

Gear shear occurs in motorcycles where the engine and transmission share the same oil. In addition to the shear forces the transmission gears exercise upon the oil, wet clutches deposit clutch friction material into the lubricant, also contributing to contamination/brake down of your oil.
Typically I notice a loss of lubricity before before the recommended change interval.
Next time you change your oil, place a drop of your old oil on your finger and rub with your thumb. Then place a drop of your new oil on your finger and do the same.
I bet that new oil feels more slippery than your old oil .

Have you ever changed your oil and felt your bike shifts better?
That is because the new oil still has all its wear additives and friction modifiers intact and doesn't have any deposits from combustion and clutch wear in it yet.

So, you can send your oil in at various intervals to determine at what point your oil is no longer giving the protection needed, follow the manufactures recommended type /interval for oil changes or use my back woods method of '"does it still feel slippery?'":toothless
DT

 

[ctwo]

I think my Honda 1100 Shadow specified 8k oil change interval. I think it would have been fine for that bike.

 

[RickM]

I believe my KTM calls for 8k mile oil change. I was planning to go 5k like I did on my vfr. But just past 4k shifting is gotten notchy. So setting at 4k oil changes on that

 

[Busy Little Shop]

What is gear shear?

Not just gears... Shear Stability is a measure of the amount of viscosity an oil
may lose during operation. Oil experiences very high stresses in certain areas
of the engine such as in the oil pump, cam shaft area , piston rings, and gears
or any other areas where two mating surface areas squeeze the oil film out
momentarily... but technically speaking as our oil shears down we don't see
elevated wear rates because oil analysis shows as viscosity shears down the
flow goes up and the concept of lubrication states the greater the flow the
greater the parts separation...

Understanding in the correct term of increase gravity flow we understand why
Honda's engineers can safely recommend 8,000 between oil changes...

How a oil's viscosity is graded 30 or 40 or 50...
1) oil goes into the hopper...
2)heat is applied...
3)the gravity flow is measured by a stop watch...

That's it... viscosity is a measurement of flow not size or weight...

 

[Busy Little Shop]

Typically I notice a loss of lubricity before before the recommended change interval.
Next time you change your oil, place a drop of your old oil on your finger and rub with your thumb. Then place a drop of your new oil on your finger and do the same.
I bet that new oil feels more slippery than your old oil .

Do we need to calibrate our fingers???

 

[ctwo]

Next time you change your oil, place a drop of your old oil on your finger and rub with your thumb. Then place a drop of your new oil on your finger and do the same.
I bet that new oil feels more slippery than your old oil .

Gnaw man, that's because you have two drops on yer thumb :thumbup

 

[Busy Little Shop]

Any idea where Redline fits in there?

Sorry... I don't have any Redline info... google search for "virgin oil sample"...

 

[Butch]

An old racer dude told me...”oil is like religion, they are all different, yet...”

I’ll stop there.
Lotsa good stuff here.
Oil analysts is the best way to figure out what is going, and is a fantastic predictive tool. It is not cost effective for a motorcycle, or even a car with substantial oil capacity.

Changing the oil frequently is the best advice.

In my opinion, and with the mileage we put on bikes, and all the other factors... I think... it really doesn’t matter.

I do think changing your oil unnecessarily frequently is environmentally irresponsible.

Just my opinion. Like religion.