Oil Change

[pistonbroke 66]

I'm sure this has been asked a million times before but after investing a whole £8 in a new oil filter whilst wandering round stafford show I wondered what the current preferred option was on oil?

I know it needs to be 10/40 but wondered what people were going for these days. I looked at the silkolene classic range but nothing seems be particularly reccomended.

Any guidance gratefullly recieved.

[hairygit]

Bryan J who has many years working with these old Hondas says Tesco's diesel oil is the correct spec, reasonably priced, and synthetic oils are an expensive waste of money.

Sent from my X6pro using Tapatalk

[Clem2112]

Any 10w/40 mineral oil.
 Euro car parts sell it.

[Integra99]

Interesting post.. so really Tesco 10/40 works well.. on these old bikes.. is it ok for the clutch?

I always use Motul in my race bikes but a cheaper option sounds good on the classics!

[hairygit]

It's fine with the clutch, it's exactly what Honda specified for them A few synthetic oils will make the clutch slip.

[Nurse Julie]

I use Trade semi synthetic 10/40 in my CB400/4. Never had clutch slip but gets changed every 1000 miles.

[Integra99]

Sounds good!

[Moorey]

I was looking for the Tesco oil yesterday and their website says its no longer available. 

[Bryanj]

A lot of firms still do straight mineral, you just need to look at the spec but do look at the diesel variety as the spec on those is what is needed

[Rob62]

https://applications.castrol.com/oilselector/en_gb/c/recommendation?_ga=2.75409493.634891134.1508360684-317217138.1508360684&vehicleType=motorcycles-scooters-mopeds-quads-(atv)&manufacturer=honda&model=cb-(1969-)&modelType=cb-750-four-(1969-1978)

[Integra99]

As I'm being lazy does anyone know the exact spec for oil on the CB400f?

[Dave487]

The little Honda handbook says to use a high detergent oil to meet or exceed the requirements for 'Service SE'. with a viscosity of SAE20 or SAE20W for winter. Or a multigrade SAE 10W-40.
The service SE spec is for petrol engines made before 1979 and has been superceded several time to meet the requirements of modern engines and fuels and is now up to service SN.
This could be quite important now that we are forced to use fuels with 5% or more ethanol.

The link below is quite interesting.
http://www.kewengineering.co.uk/Auto_oils/oil_quality_ratings.htm

[K2-K6]

That's an interesting site Dave487, I haven't seen that one.

Thanks for posting it.

[Rob62]

Talking of ethanol, i presume you guys use premium petrol in your classic 4strokes? I always do in my strokers and intend to with the cb750 once its otr... for a couple of extra quid per tank full it has to be worthwhile?

I avoid supermarket petrol like the plague! Except tesco premium which is quite good i believe 

[Nurse Julie]

I never use premium and only ever use the cheapest supermarket fuel I can find. You will get lots of differing views on that question 
Edit....and before anyone says anything about the state of my pistons......don't!!!!