Oil Question.....

[Vince Lupo]

I've heard different things from different people, so I thought I'd throw it out there for the members to get their opinions. My '66 Honda CB77 SuperHawk 305 has a centrifugal oil filter, and the owner's manual (circa 1966) recommends using 30w non-detergent oil. Now, oils have certainly advanced over the last 40 years, so does that recommendation still hold? As well, I ride this bike in all kinds of temperatures - from 40 degrees to 90 degrees - so I don't know if that affects my choice of motor oil.

So, my questions are this:

i) Should I stick with 30w non-detergent, per the Honda manual's recommendations?

ii) Should I use a multigrade, like 10w40?

iii) If I should use a detergent oil, should it be a 'low detergent' or a 'high detergent'? Does the detergent affect the operation/effectiveness of the centrifugal oil filter?

iv) Is there such a thing as a non-detergent multigrade motor oil?

v) With this type of oil filter, should the particles be suspended, or should they be allowed to settle on the bottom (assuming that a detergent oil causes the dirt to be suspended, and the non-detergent causes the dirt to settle on the bottom)?

Many thanks!

 

[DrJ]

You're overthinking it. Old Honda motors are not picky about what oil you use. Any modern oil is better than oil available 40 years ago and will provide more than enough protection. The oil I've used with the best results is Motul 5100 10-40 semi-synthetic.

 

[johnson_steve]

Don't use car oil on a bike! you'll mess up your clutch. there are oils made for bikes but they can be expensive. a lot of guy's around her seem to use this stuff shell makes for deisel trucks it's suposed to work good and it's way cheaper. I'm going to put that in next year, but I don't know the exact name. I ran Mobil 1 fully synthetic 10w40 all summer in my cb400 and it worked great. I rode it hard all summer and the oil still looks good, but it cost almost $50 just for the oil.

 

[DrJ]

I feel full synth is overdoing it with old motors and not worth the cost. Motul is motorcycle oil and 5100 is around $30 for a 4 litre jug here in Toronto. Yes many riders swear by Shell Rotella but they also report an unpleasant odour when using it.

 

[Roustabout]

I started using Shell Rotella T with some Lucas engine break-in oil additive to boost the ZDDP. I believe there is a thread on the board somewhere explaining the ZDDP issue with most modern oils.

 

[johnson_steve]

That's the stuff; Strange odours?

 

[Vince Lupo]

You're overthinking it. Old Honda motors are not picky about what oil you use. Any modern oil is better than oil available 40 years ago and will provide more than enough protection. The oil I've used with the best results is Motul 5100 10-40 semi-synthetic.

Thanks for your reply -- as you can see from some of the answers, there are varying opinions.

What about that centrifugal oil filter? If after 1500 miles, let's say, we pull the oil filter and it's clean, should I be concerned? If the oil I'm using isn't allowing the filter to do what it's supposed to do -- that is, assuming that certain oils cause the dirt particles to behave in different ways -- should I be reverting to the oil that it was 'meant' to use (i.e. 30w non-detergent), or should I just get the best oil that's available, regardless of whether it's a multigrade, detergent or whatever?

And my understanding about synthetic was that it could possibly cause clutch slippage? Or am I wrong on that?

 

[Vince Lupo]

Since January last year (2008 ;D) the ZDDP level in all oils has been dropping.
The oils of 30~40 yrs ago had around 1400~1500 PPM ZDDP, which has been lowered to ( if I remember right) 1085 PPM and is going tto get even lower in automotive oils as it messes up catalitic converters
Motorcycle specific oils have levels around 1200 to 1400 PPM but as new bikes are coming onto market with 'cats' its probably going to be lowered
PJ

Sorry, but this is all foreign to me -- any idea what this translates to in terms of my particular question?
??? ??? ??? ??? ???

 

[Vince Lupo]

Well I decided to go to the source: I contacted Castrol and asked the 'experts' what oil I should use. Their answer: 30w non-detergent, and that was based on the age of the engine and the type of oil filtration it had.

So there you go....