[PietiePoo]

Hey everyone. Hope you're having a wonderful day.

I own a Honda CB125R 2018 (125cc, single cylinder, 4-stroke) and am approaching two years of riding. That means it's about time to change the coolant. Even if it isn't, I still need to drain it, for reasons I'll come back to in a minute. However, it seems my bike has no coolant drain. Please refer to the image provided.

Encircled is what I believe is access to the coolant pump. However, as far as my knowledge goes, this is usually where a coolant drain sits. Which as you can see, on this bike, it doesn't.

Some of you might say it's too early/not necessary yet to change the coolant on this small bike, but even if you're right, I still need to decouple the encircled part because I require access to the right side of the engine block.

Here's my question: is this the way to drain the coolant on this bike? It does seem to be the lowest point in the loop, and I cannot find a drain anywhere else on the bike. I found no guidance in the owner's manual either. I think it's strange Honda provided no (apparent) way to leak the coolant, but given the fact this bike doesn't even have an oil filter, it wouldn't surprise me.

Many thanks in advance! 😄

 

[Trials]

See that rubber hose with the screw clamp on it, if you pull that off you will have anti-freeze everywhere except in the rad. Try not to spill too much or get it on you, I hear it's slightly toxic.

Owner manual is useless, you need to procure a Service Manual for that bike. Ideally one from Honda.

... and at this point you should worry about changing your fork oil and brake fluid more then your rad coolant.

 

[PietiePoo]

See that rubber hose with the screw clamp on it, if you pull that off you will have anti-freeze everywhere except in the rad. Try not to spill too much or get it on you, I hear it's slightly toxic.

Owner manual is useless, you need to procure a Service Manual for that bike. Ideally one from Honda.

... and at this point you should worry about changing your fork oil and brake fluid more then your rad coolant.

Changing fork oil seems a bit early. I have only 6,500km on this bike and I exclusively ride streets. It's safe to say my forks don't face that much abuse; with my current riding behavior I'm planning on replacing fork oil at 20,000km. I don't know about braking fluid though. What's your brake fluid regime?

 

[Trials]

Fork oil has no filtration system, if there is water from condensation or direct intervention past the seals plus dirt and metal particulate from the wear inside your forks, all that stays inside the forks and becomes grinding compound. Changing out your fork oil annually would not be over-kill.

Regular old brake fluid is hygroscopic, it absorbs water right out of the atmosphere. Even a small amount of water in your brake fluid can lower the boiling point of your brake fluid. That is what destroys brake fluid, water. Change it when you notice a change in the fluid colour or any time you suspect water is in the system.
(Do your brakes need bleeding occasionally? When water boils it makes steam. Brakes can get hot enough to boil water.)

 

[Trials]

BTW: Always drain your fork oil into a clear glass container, so you can hold it up to sunlight and see how much debris and metal particles are in it.

 

[SemiFast]

I cannot find a drain anywhere else on the bike

I can't find a parts diagram for your bike so I can not see a parts breakdown but...
The coolant drain is probably incorporated in / with the bottom water pump housing screw. If it is there you should be able to see a brass washer under the screw. You'll have to clean the screw very well and look very closely to see the washer.
Remove the radiator cap, loosen the screw a little and the coolant drains.

S F

 

[WintrSol]

Go to page 167 of this document: Honda CBR125R Owner's Manual (Page 167 of 430) | ManualsLib

 

[Trials]

Invest in a quarter inch drive torque wrench now and it will last the rest of your life if you take care of it. ... and maybe a half inch drive one too for the bigger bolts on your next bike.

one season old fork oil

 

[PietiePoo]

Go to page 167 of this document: Honda CBR125R Owner's Manual (Page 167 of 430) | ManualsLib

Thank you SO much for showing me this website! I consider my issue solved. Have a great day everyone.

 

[WintrSol]

Found it with DuckDuckGo; my friends come to me for searches, as I can find things they can't. It's amazing what can be found with the proper search terms.

 

[hogcowboy]

Found it with DuckDuckGo; my friends come to me for searches, as I can find things they can't. It's amazing what can be found with the proper search terms.

Certain search tools(google being one) will only show you certain things based on your search history though. So sometimes it's the persons fault for not finding things although some don't even try.

 

[SemiFast]

Remove the radiator cap, loosen the screw a little and the coolant drains.

If you also remove some of the lower hose clamps and disconnect the hose/s you can get a little more of the coolant to drain.

S F

 

[WintrSol]

Certain search tools(google being one) will only show you certain things based on your search history though. So sometimes it's the persons fault for not finding things although some don't even try.

The fact they retain a search history is why I no longer use google. DDG is a lot more privacy oriented, and usually provides great results, not colored by past interests.