Car oil into a bike?

[J0Al1]

A friend wants to know . . .

Can you put Car 10W-40 A3/B4 Part Synthetic into a non sports 4 stroke bike?

[Kradmelder]

[J0Al1]

CBF125

Usually takes semi...

[nowhere.elysium]

10w40 semi-synth is fine for a CBF. Make sure that it's not got any friction modifiers in it, though, otherwise you'll get clutch slippage. It'll usually say on the bottle if it does contain friction modifiers (at least, that's my experience).
____________________
'10 SV650SF, '83 GS650GT (it lives!), Questionable DIY dash project, 3D Printer project, Lasercutter project

[weasley]

You can mix mineral, semi- and full-synthetic if you like, it just means you're wasting the performance of the better component of the mix.

A 10W-40 is unlikely to have friction modifiers; they tend to be used in oils aimed at fuel economy.

It'll (probably) be fine.
____________________
Yamaha XJ600 | Yamaha YZF600R Thundercat | KTM 990 SMT | BMW F900XR TE

[Fizzer Thou]

[daemonoid]

Some oil is always better than none. If 10w40 is all you have then go for it. You may notice clutch slip or a bit of overheating but in a pinch (and especially in winter) go for it.
____________________
current: ducati monster 750
past: hyosung gt250r, bajaj pulsar 180, hyosung gt 125 comet
@thomasgarrard | www.straitjkt.com | www.racingseven.com

[MarkJ]

[J0Al1]

I have the oil already, I can easy go get bike oil if this might cause damage .... Its just whether I should be arsed or just use this.

It is Castrol and does not mention friction modifiers.

If the only risk is a vague chance of clutch slip then hey ho.

[Lord Percy]

My oil is a big green container from a Tesco petrol station, it says 10W40 part synthetic and was the cheapest one going. I don't know any more than that, but oil is oil is oil!

[Polarbear]

if you love your bike, pour some 10w40 in it
or have sex on the saddle, it will like you too, lol
____________________
Triumph Trophy Launch Edition

[mentalboy]

Modern oils are great for reducing friction (thus preventing wear). Motorcycles generally nowadays have wet clutches which are lubed by the engine oil.
If you use a cheap engine oil that does not have friction modifiers in it then your clutch will slip, this is why bike oils tend to be pricier. A 10/40 car oil will almost certainly not be suitable for a wet clutch bike.
Just because it says oil on the side of the container it doesn't mean it's good for your engine. Sure it'll run but for how long? If oil is oil then why not use cooking oil or baby oil. Cheap is not always cheerful.
____________________
Make mine a Corona.

[temeluchus]

[flumpy7]

[DrDonnyBrago]

[Kickstart]

Hi

I have used car oil in bikes loads of times, including fully synthetic car oil, without any clutch problems. Only clutch slip was on the bandit when first tuned and that slipped with brand new clutch plates and bike oil in it anyway.

A few car oils can cause issues. Castrol magnatec seems to be one people do have problems with

All the best

Keith
____________________
Traxpics, track day and racing photographs - Bimota Forum - Bike performance / thrust graphs for choosing gearing

[cb1rocket]

I assume the poster has castrol GTX 10w - 30? If so its fine

[stinkwheel]

If it's castrol GTX. Crack on. I put 70k miles on a GPZ500s running it on GTX changed every 3,000 miles.

Still have the engine, the cams are like new. It's had one set of clutch plates.

The clutch did start to slip one time I put GTX magnatech in and stopped slipping after I drained it and replaced it with normal GTX.
____________________
“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[Rogerborg]

[janner_10]

https://i1-groceries.asda.com/g/998/867/5050854998867_21000_IDShot_2.jpeg

£16 for 5L - job done!
____________________
Yamaha FZS600 (Now gone to heaven) > CBR600F4i (SOLD) > '99 YZF-R1

[J0Al1]

Christ, I didn't realise oil was so complicated. . .

It is Castrol Magnetic 10w-40 part synth.

[stinkwheel]

[weasley]

Conventional advice is to avoid Magnatec for bikes, however it isn't a clear cut thing. A CBF125 may not produce enough torque to slip a closed clutch even if the oil isn't a perfect match.

That said, take a look here - it is promotional guff but outlines some of the technical jiggery-pokery.
____________________
Yamaha XJ600 | Yamaha YZF600R Thundercat | KTM 990 SMT | BMW F900XR TE

[J0Al1]

OK, I shall change it for either bike oil or GTX tomz.

If he manages to get the break callipers/handle bars back on in time for riding it tommorow, . . . then he has to run it with whats in it for now.


Yup, thats the bike Roger.


Thanks for all the opinions

[Walloper]