Oils for early 70's Hondas?

[edhackett]

Specifically a 1973 CB350F, the neat little four cylinder. I've wanted one of these for oh, about 39 years. These were new when I was 16. I had to settle for a used CL350. I've found a less than 10K miles, all original example, and the purchase process has begun.

The manual calls for 10W-40 at all temperatures and 20W-50 above 59F. I'm also guessing that a 10W-40 with a strong additive pack is the best for this small displacement engine. The logical first choice would be T6. I figure any of the HDEO and MC specific oils, even are far, far better than anything that was available then. This is BITOG after all, so have at it.

In a previous thread hal2626 said: I use Mobil 1 15w50 in my 08 865cc twin... I use this in all my bikes except my CB750K.

OK, what do you use in the 750? I'd be happy to hear from folks with recent experience with early 70's vintage Hondas.

Ed

 

[Chris142]

If the engine in that bike is anything like the ATC's me and my friends had in the late 70's and early 80's any oil will do. Couldn't kill those things!

 

[dwendt44]

Rotella should work fine.

 

[car54]

I had a CB360 a long time ago, used rotellaT 15w-40. It's probably had five owners since me, and probably still runs as good as the day it was new.

 

[grampi]

Originally Posted By: edhackett
Specifically a 1973 CB350F, the neat little four cylinder. I've wanted one of these for oh, about 39 years. These were new when I was 16. I had to settle for a used CL350. I've found a less than 10K miles, all original example, and the purchase process has begun.

The manual calls for 10W-40 at all temperatures and 20W-50 above 59F. I'm also guessing that a 10W-40 with a strong additive pack is the best for this small displacement engine. The logical first choice would be T6. I figure any of the HDEO and MC specific oils, even are far, far better than anything that was available then. This is BITOG after all, so have at it.

In a previous thread hal2626 said: I use Mobil 1 15w50 in my 08 865cc twin... I use this in all my bikes except my CB750K.

OK, what do you use in the 750? I'd be happy to hear from folks with recent experience with early 70's vintage Hondas.

Ed


Those are sweet bikes, and they were a technological marvel when they came out. It's hard to believe Honda only produced that model for 3 years. I wonder how difficult it is to find parts for those now? Congrats on the nice bike and enjoy! I'd like to see pics if you can post some...

 

[Honda_Fan]

Another vote for Rotella. Either T or T6, your choice. I don't think the engine would care either way.

Neat in the CB-350F was the only production 4-cylinder 350. My dad had one when they first came out, Candy Apple Red. And yes, those engines are bulletproof. Ride it and enjoy.

If memory serves, the only trouble people had with those Honda inline 4's were with the Carbs, but you couldn't kill the engines. This was back when Honda over-built everything. Probably one reason so many of the Inline 4's are still on the road (CB-750's in particular).

BTW Ed, my dad's friend had the 2-cyl version of the 350. Around town there was no difference at all. Only out on the highway (or in high gear) did the 4-cyl version really come into play and show superiority over the twin.

 

[Cujet]

I would choose Mobil 1 MX4t, in either 10W-40 or 20W-50 depending on conditions. With Rotella as a second choice. The M1 has a more robust additive package. The diesel oils, while excellent are also trending downward in ZDDP.

 

[Robenstein]

Originally Posted By: Cujet
I would choose Mobil 1 MX4t, in either 10W-40 or 20W-50 depending on conditions. With Rotella as a second choice. The M1 has a more robust additive package. The diesel oils, while excellent are also trending downward in ZDDP.


So are some moto oils. Look at the Kendall Moto oil....very very disappointing in the ZDDP department.

 

[RC46_Rider]

Hi.

I suspect your are worrying about a non-issue. You are correct: modern oils are better than those '70's oils by a significant amount. I will be the odd man out and say I would NOT run a synthetic in that motor. Reason: slight chance of chemical incompatibility with old seals, gaskets, etc. I would stick with a good petro oil. I think you stand the chance of oil leaks with a synthetic as they do penetrate a little better than a petro oil.

If you are going to ride the bike frequently or daily, the smart money would be on a major brand HDEO in 15W-40. If it is infrequently ridden, I would suggest a 10W-40 to give quicker oil flow and lubrication at start up. In a well maintained engine, much of the wear occurs at "dry start up", so an oil that flows fast is better. I am assuming you are not going to race it or flog it hard, so really, any "good" oil will do. You are NOT going to wear it out! Those engines were in a pretty mild state of tune, relatively, again reducing the stress on the oil.

For the Record: I am quite Jealous !! That is a NEAT bike!
Too bad they won't make stuff like that anymore. Based on my
experiences over many years of riding, 350cc is a very good engine size: enough zip that you can ride them on a highway and small enough to be very friendly and frugal. Have fun....

 

[Robenstein]

Delvac or Rotella would work just fine in that old beast. My pops runs rotella in his 69 CB750 with no issues.

 

[Scoot_4_20]

I'd definitely run T, T6, Delvac, Delo, or any 15w40 HDEO, unless you want to pay 2 to 4x more for a boutique oil that's probably no better.

I ran Delvac 15w40 in my Honda 750 Nighthawk, my Honda Elite 80 scooter, and my 'new' 1983 Hondamatic 450, all with excellent results.

Put some Delvac in it and you will be glad you did.

 

[Steve S]

Torco motor oil ???

 

[Robenstein]

Delvac or Rotella are miles better than the old 70's oil. Go with them and have confidence you are protecting that old mill.

 

[ddrumman2004]

I had a CB 350 four back in the day......nice machine...very stable at high speeds as I remember.

I use Shell Rotella in a 1975 CB 500 twin that I own..works for me.

 

[Lost1]

Another vote for HDEO- Rotella, Delo, Delvac, etc.