Triumph vs Honda oil compatibility/differences...

[MGPD03]

So I have a 2014 Triumph Street Triple R, a 2018 Honda CRF250L, and my son's project 1971 Honda CL450K in my garage right now. My question is this:

I use Castrol Power 1 4T 10W40 in my Triumph which has a smidge over 8k miles on her and my lil CRF250L is coming up on her first oil change (600 miles) soon. Honda specs 10W30 for the CRF250L, but would just using the same Castrol 10W40 be THAT far out of spec? It won't break my heart (maybe my wallet) to just pop on down to the Honda dealer and grab some of their GN4 10W30, but if I could just keep one MC oil in the garage it'd be a help. Thoughts?

Also, any recommendations for the son's CL450? I'm relatively sure it'd happily run whatever was in it, but I'm always open to advice.

Thanks in advance!

 

[jeff78]

Originally Posted by MGPD03
I use Castrol Power 1 4T 10W40 in my Triumph which has a smidge over 8k miles on her and my lil CRF250L is coming up on her first oil change (600 miles) soon. Honda specs 10W30 for the CRF250L, but would just using the same Castrol 10W40 be THAT far out of spec? It won't break my heart (maybe my wallet) to just pop on down to the Honda dealer and grab some of their GN4 10W30, but if I could just keep one MC oil in the garage it'd be a help. Thoughts?


The 10W-40 will be a bit thicker at operating temperature (actually, at pretty much any temperature) - on a small displacement single you might actually be able to feel this (maybe a little lazier revving, etc).
I'm inclined to say that since it's a new bike that's under warranty and arguably still breaking in, stick with the recommended viscosity for now, and then experiment with the 10W-40 later if you want.

 

[Bjornviken]

use 10w30 in that bike

 

[skyactiv]

Honda specs a 10W30 in lots of modern bikes, but NOT the energy conserving type meeting the latest API spec meant for cars. It says API SJ on the bottles of the latest Honda GN4.
The reason is Honda did testing and the thinner HTHS 10W30's cause faster wear of the transmission. The Honda 10W30 has an HTHS of 3.5.

 

[Lawn_Care]

If it was air cooled, i'd definitely use the 10w40. But since it's liquid cooled, I can't see a 10w30 being an issue - even in the heat of summer.

 

[Bonz]

I agree, 10w30 is what Honda recommends, however does not mandate or require. A recommendation can not dictate an absolute. 10w40 will be no issue whatsoever, given that it's been proven over and over and over again most wear occurs at cold start up and a 10w-xx has to meet the 10w on the low end no matter what the top end number is. Tolerances in these engines will not cause a self-destruct or compromise long-term viability by running a 10W-40.

As has been said, if you have any doubts wait till the warranty is up, however it is a thin argument at best that Honda would somehow not honor the warranty. NEVER heard or read of that with any motorcycle, car, or SUV, despite it coming up in every thread like this at some point. In fact I haven't heard of an oil related issue/failure with a modern engine, as long as there was oil in it.

As Honda markets a non-energy conserving 10W-30 oil, you will not go to the auto parts shelf and pick up a non-energy conserving 10w30 oil from another manufacturer. Notice how you noted you will have to go to the dealer to find it.

The transmission as you know will work over the oil pretty well and sheer it down, certainly so in a single cylinder 250 where it will spend most of its life running a high rpm where those tranny gears are spinning very fast. 10w-30 will be a 20 wt at some point (sooner rather than later?) in the recommended 8,000 mile (or 1 yr) oil change, especially if you choose the conventional version of Honda GN 10w-30. The few analysis' I have found show it shears fairly quickly.

However if the bike is used leisurely and gets 1000 miles a year, any oil won't suffer terribly.

In any case I would not hesitate to run your Castrol Power 1 4T 10w-40.

 

[kmrcstintn]

any heavy duty/diesel 10w-30 might be a good alternative...buy a gallon you get 2 oil changes & usually less expensive