Looking along a long straight road amidst lush green farmland

Home Ren's Biking Blog

As Not Recommended By Honda

Honda recommends their own "Pro Honda HP Coolant" in the owner's manual of my 500. I checked my coolant the and noticed it was on the minimum mark so duly took myself to my Honda dealership to purchase the correct fluid. According to the wisdom of the forum (not always to be trusted) Pro Honda HP Coolant is a type 2 coolant which means it contains no silicates and has OAT, Organic Acid Technology. To backup this information I found this webpage - prohondaoils.com/maintenance/hp-coolant/

The notion behind non silicate based coolants is the silicates can be abrasive. As such the actual coolant can cause wear on seals and the water pump itself. Instead some genius engineering wizards sussed out a bit of acid may slow corrosion down. OAT is most likely sales talk for lemon juice (lemon juice is acidic) squeezed into a mix of distilled water and a glycol of some kind.

Armed with this knowledge from the forums and my internet research imagine my surprise when the Honda dealership parts department plopped a bottle of Castrol coolant on the counter, priced at £5.99.

"Is it type 2?" I asked. 
"I mean is it the silicate free stuff?"
"No that's £9.99." pointing to a bottle of Motul silicate free coolant. Looking back at the Castrol I'm told "We've been using this Castrol stuff for 15 years with no problems."

What!? If Honda recommends using rabbit urine collected on a moonlit night by a hobgoblin I expect my Honda dealership to follow this protocol to the letter. I could *almost* accept they might possibly suggest a non Honda silicate free alternative to owners of motorcycles that are out warranty. They may have been using this other product without issue but then most people do 3,000 miles a year on their bike so it's very unlikely they'll ever have an issue within the warranty period. If you turn up with a leaking motorcycle at 45,000 miles then their advice will be "What do you expect at this milage?"

Luckily I notice a bottle of Pro Honda Coolant on the counter. I note this is NOT Pro Honda HP Coolant, the "HP" is missing. However the bottle does state that it is type 2 and it is Honda's own product. This bottle is the same price as the wrong Castrol. The parts person assures me this too will be fine for my Honda. "I'll have that please."

A 1 litre bottle of honda pro coolantIt's NOT HP but at least it is Type 2 and Honda.

Why should I be bothered? Warranty - that's why. Imagine I'm riding through Germany on my 500 when it springs a leak. Being under warranty I take it a Germanic Honda dealership. They decide the leak is due to using the wrong coolant. They demand payment for the work. Marvellous, thanks local Honda for using/supplying the wrong coolant.

Before I sign off let me make something clear. I fully understand that you and I have used tap water and a little additive for years with no ill effects. I know the world has gone CRAZY when coolant (ie distilled water, cheap glycol and a bit of lemon juice) is more expensive than good quality oil. I am sure the whole thing is an unnecessary rip off. I am sure Honda et al are on a money making scam. My point is I expect my Honda dealership to follow Honda's recommendations to the letter, no matter how ridiculous those recommendations may be.

My manual recommends 10W-30 oil. My 8,000 mile service receipt suggests they used 10W-40. I know this isn't a problem but ARGH!!! If Honda says use extra virgin olive oil made in Northern Italy during the autumnal months and pressed by women over the age of 50 wearing green shawls on a Tuesday evening then I know this is beyond stupid. But I'd still expect my Honda dealership to only use extra virgin olive oil made in Northern Italy during the autumnal months and pressed by women over the age of 50 wearing green shawls on a Tuesday evening.

We'd love to hear of your motorcycling experiences. Have you got an interesting story, a point to make or a road to recommend? Drop Ren a line - ren@bikesandtravels.com

Reader's Comments

Ian Soady said :-
Coolant is weird. Almost all cars made in the last 15 years or so use OAT stuff (usually pink). However, bikes still seem to use the non-OAT "conventional" stuff. I wanted to use OAT in my Super Four as it's what I use in both our cars and would prefer to only have one type. OAT also has a longer installed life (typically 5 years as opposed to 2 for conventional). However, I asked everywhere I could think of and nobody could actually tell me whether it would be OK.

So I went for the conventional stuff as that's what was already in it. There can (allegedly) be a problem if you don't flush VERY thoroughly when changing from one to the other as they can apparently react with one another and form a jelly. But I have no experience of this.

Some internet sources will tell you that OAT was invented by GM or some other US car manufacturer to increase its profits but I have no way of knowing whether (or how) this is true.
16/02/2017 02:06:55 UTC
pocketpete said :-
When I changed my Honda oil due to the lateness of my booked in first service. He have me Castrol (really expensive oil) The running in oil was a dark almost blue colour. The castrol had a distinct red colour to it.

When I had my main first service done where they changed the oil filter the oil had a more normal golden colour. I know they simply put bulk oil in but I have just got some more oil off them to do another change at the half way mark to my 8000mile service. This is shell oil and looks reddy brown. Thye are selling it so I presume it complies with the Honda rule book. The shell stuff seems quite thin compared to the castrol. I have about 1 litre left of the castrol.

Is it possible to mix them together? They are all 10w-30

16/02/2017 06:31:26 UTC
Ren - The Ed said :-
Hi Pocketpete. To the very best of my knowledge it is acceptable to mix oils and I have done so in the past without issue. However I'm not an oil expert! I will be interested to hear if it makes any difference to the clutch issues you have.

Just because they're selling it to you as per the point of this missive doesn't necessarily mean it is correct! If you consult your handbook it does state various specifications it must meet. Again my gut tells me you'll be fine but again I'm not the expert.

Ian - the OAT coolant I purchased for my car is pink. I haven't yet opened the Honda stuff but I hear tales of it being both green and blue. Currently the coolant in the 500 is blue. I would hope there would be nice simple colour protocols but of course Honda's thrown these out of the window.

I too have heard that terrible things may happen if you so much as even allow a single drop of the types to mix. Your engine will disintegrate, the water pump will melt, monsters will attack your firstborn and pestilence will befall you. I'm not convinced but then I have no desire to find out the hard way.

Of course it's a moneymakers scam. Eeeee when I wur a lad wur nay problem wiy a bit o water n some blue stuff wot stopped it freezin. An tha never changed eet. Tha just topped it up wunce in a while.
16/02/2017 07:32:04 UTC
Spacepig said :-
I know when the new Liebherr waste grab got commissioned at work one thing they specifically said to me was only use pink coolant never put anything else in it
20/02/2017 08:44:30 UTC
Phil B said :-
Exact same issue today.
Coolant on low mark, phone dealer as will be passing later. "Got any HP coolant in"?
"No, we don't sell it, we use Motul"
01/05/2018 07:32:40 UTC
Ren - The Ed said :-
Cheers Phil. It's a fair old thing to note that Honda dealerships DON'T sell genuine Honda products. Then they have the audacity to suggest that warranties could be voided if third party mechanics do not use genuine Honda products.
02/05/2018 10:36:22 UTC
Borsuk said :-
Seeing this thread reminds me to check the coolant in my Suzuki Alto. Its been serviced twice by a dealer and in between by myself in it's 7 year of life and I have no idea if the coolant has ever been changed or not. I know it has never been topped up as the level had never changed in that time. No idea what type it is either, it is a virulent green but colour means nothing as I have seen pink OAT coolant and pink glycol coolant made by the same manufacturer.
Before I ever heard of OAT coolant the different manufacturers made them any colour they could think off or was the cheapest dye colour that month.

Think I will take a couple of samples from the radiator when I get home next month and mix it with both Glycol and Oat coolants and see what happens.
02/05/2018 11:47:58 UTC
Ren - The Ed said :-
From what I am lead to understand - this is not gospel - it's to do with the aluminium engines and something about the pumps.

Ally engines corrode so there is some sort of anti corrosion additive. This additive turns out can be abrasive and wear out water pumps. So we end up with different coolants for iron and ally engines then different coolant for certain water pumps.

I think somebody somewhere engineered in problems so they could engineer in expensive solutions(sic). I remember when I were a lad we used to put water in. If you were the really careful knowledgeable type you might mix in a bit of cheap anti-freeze too.

Then when the water pump failed you'd replace it.
03/05/2018 03:04:08 UTC
Rod said :-
Thing were much more simple in the good old days. Air cooled engines, or in the case of some thirsty 2 strokes, petrol cooled lol.
03/05/2018 04:06:59 UTC
Ren - The Ed said :-
Yeah Rod, and everything was black and white. Damn those people who invented colour!
03/05/2018 07:58:27 UTC
Ian said :-
I've got exactly the same problem. Bike in warranty and coolant os very low. I went into a Hondal dealer in Sheffield yesterday. He offered me 2 bottle of Silkolene coolant - no Honda coolant in stock. He had no idea which coolant I should use. Similar in Shipley - 1 castrol bottle and 1 Motul. Like ren, I'm bothered about Honda refusing a warranty repair as I haven't used the recommended coolant. Very strange service from Honda dealers
03/02/2019 03:57:00 UTC
Upt'North said :-
Dave Silver will post out the Honda Pro Coolant.
03/02/2019 04:25:55 UTC
Ren - The Ed said :-
Good call on David Silver. I've found this Honda Pro Coolant, it's the same as the one I've used.
04/02/2019 08:52:39 UTC
Ian Soady said :-
Interestingly that doesn't state whether it's OAT or not. However, the link below refers to Honda HP Pro which states that it is. Whether HP is different I have no idea.

I really wish manufacturers would give us a technical data sheet or at the least tell us what's in their stuff. Although of course Honda don't actually make it.....

Solkolene used to be really good with providing data but they've now gone down the omerta route.
04/02/2019 10:19:56 UTC
Steve said :-
I used a Rock oil Kool coolant for my Honda when it was 2 years old and out of warranty. It was recommended by wemoto and still is. After the first coolant change i noticed spray around water pump area, i thought it was the hoses and changed them and went on a long tour. result water pump seals slowly failed and i had to limp home and purchase a new water pump.i checked with Rock and they said Kool had silicates!!

After changing the water pump out I filled up with pink stuff from Halfords OAT coolant. No problems in 20k so far
04/02/2019 07:22:42 UTC
Pocketpete said :-
Just topped mine up with pink stuff from halfords quite cheap and oat friendly no silicates so should be just the thing.

Quite a few reports of cb500x water pumps failing I wonder if it's because Honda dealers put the wrong stuff in.
04/02/2019 08:16:26 UTC
Ren - The Ed said :-
There's more to come on this from Pocketpete. I'll get the post up soon Pete... work keeps on getting in the way!
06/02/2019 09:10:57 UTC
Rob Skinn said :-
I had a problem with coolant leaking out of the water pump seals on my Honda NC700. When I drained the cooling system, there was sludgy residue. I’ve only recently figured out that the coolant was to blame. Unfortunately I can’t remember which coolant it was but I suspect it was Castrol motorcycle coolant ‘for any motorcycle’ as that’s ‘good value’ and has a ‘brand name that you can trust’. So it turns out you can use it in any motorcycle so long as it’s not a Honda! Go figure.

My coolant of choice is now Rock Oil coolant. It doesn’t contain silicate or phosphate and is it’s recommended by wemoto.com for my bike... so must be right eh!?
16/05/2020 04:24:50 UTC
Upt'North said :-
Don't think this has previously been posted, if so, shoot me.
You can buy large containers of the Honda Coolant at Honda Car Dealers and it is a lot cheaper than buying it by the litre. Same stuff apparently.
16/05/2020 04:57:23 UTC
Ren - The Ed¹ said :-
I'll look out for that Upt', be sure to find out if it is OAT though... unless the BeaST being of a certain age is allowed to cool itself in - dun dum DAH! - water. Heaven forbid.

I haven't seen the manual for the NC700 but I'd hazard a guess it will recommend OAT which the Rock oil is Rob Skinn.
16/05/2020 07:08:57 UTC
Borsuk said :-
I love how manufacturers seldom give the actual spec of the coolant recommended, just the name of their own brand, not even the type most of the time.
Glad mine are oil / air cooled or straight air cooled.
16/05/2020 11:06:30 UTC
Ren - The Ed¹ said :-
Don't worry Borsuk, we can make oil as complicated as you like too. Not only can we have 10w40 or 5w40 or 5w30 and so on, throw in "S" numbers, "JASO" codes and individual manufacturer's specs (Dexron for Vauxhalls as I recently discovered...).

As for the air cooled aspect, are you using the correct air? Is it genuine Enfield air because you could void your warranty if it's not. Are you using the correct grade of air for your riding style and country? You do realise if you go into the mountains you'll need a heavier grade and for winter use a lighter grade? How often are you changing your air?

I might be joking but at times it doesn't feel like it.
17/05/2020 08:08:44 UTC
Ian Soady said :-
That sludge is probably due to mixing OAT and old-style coolant. Hopefully you gave it a through flush before refilling with your Rock Oil stuff.
17/05/2020 10:12:23 UTC
Upt'North said :-
I think they call it type 2 Ed, don't quote me though. But it is the same thing.
17/05/2020 10:49:17 UTC
Borsuk said :-
Oil codes are easy, all 3 of my bikes, even my cheap Chinese knockoff tell you exactly what grade of oil to use including JASO codes and what not to use; anything with friction reducers, but none of my cars ever tell you what type of antifreeze to use. Just use Suzuki Super Cool or equivalent, then you go into the Suzuki shop and there are 2 types of Super Cool. One is blue the other pink and the stuff in my cars radiator is a virulent green colour which I have only seen before in a velcro type matter attached to my daughters nappies for the first 4 days after she was born.
18/05/2020 10:25:46 UTC
c87reed said :-
What a minefield these coolants are. I got looking as my Honda SH is due a coolant change at 3 years old. My manual (like all newish Hondas, I expect) stipulates the use of the Pro Honda HP Coolant. A google search then brought up this thread. This (below) is what I pulled from one site and gives a flavour of just how many kinds there are - and I don't even think that this list is exhaustive. It's far too easy to get it wrong, especially given that Honda are not giving the full specifications of what is required. I have contacted Honda's technical support just to see what they say.

IAT (Inorganic Additive Technology) – Silicates – Green

OAT (Organic Acid Technology) – Organic Acids – Orange

HOAT (Hybrid OAT, Phosphate-free) – NAP-free – Turquoise

HOAT (Hybrid OAT) – Silicates and organic acids – Yellow

Si-OAT (Silicated HOAT) – Silicates and organic acids – Purple

P-HOAT (Phosphated HOAT) – Phosphates and organic acids – Blue or pink

I found some that appeared suitable being Ethylene Glycol OAT with no Silicates. but then I'd seen that some others contained NAP (Nitrates, Amines, Phosphates), I didn't know if these were okay or not. I was also conscious that some coolants may contain things that they don't necessarily should about on the bottle. In the end, feeling rather defeated that I couldn't unpick the puzzle, I bought 5L of the Honda stuff for £21.60 delivered from:


It might have been a bad idea for me to buy 5L of the stuff in case I don't use it up quickly enough, but I need 1.3 litres and there isn't much of a saving to buy 2x1L. I already have about 5 other bottles of various coolant types for cars/bikes; the biggest thing I hate is the waste! Waste of hazardous substances, I will add. I think the most important step is the thorough flushing of the engine before putting the new stuff in.

Ren, I've had the same oil change scenario on a Vespa GTS300. Took it to a Vespa dealer, it was meant to have 5w-40 but they opted to fill with 10w-40 instead. From others I have spoken to it seems pretty common unfortunately. It would be interesting if the engine imploded and Honda wanted to take a closer look, only to find that the wrong oil had been used.


28/05/2020 01:47:09 UTC
Upt'North said :-
Chris, I share your frustration, sort of.
It would be really easy to be able to walk into Bloggs Auto Parts and pick up a bottle of brake fluid, engine oil, coolant etc and know it'll work. But as we both know you can't.
But of course you can and many do, but do they get away with it? Maybe, maybe not. Why does our Ed get 80,000 miles out of his tiddler and others will implode well before half that, sorry for mentioning your tiddler Ed.
Oil is discussed to the enth degree, heated arguments take place, people are insulted because they dare to buy motorcycle oil, but then of course there are many threads on early engine, gearbox and clutch failures. Is there a link you think?
You pays ya money and takes ya chance.
Good luck getting rid of old coolant, I took mine to the local tip and was told they don't treat it separately, "just chuck it in the general waste". I pointed out it wasn't probably a good idea but shrugged shoulders meant that's where it ended up.
FWIW I use Honda Coolant too for the same reasons as you and a dedicated motorcycle oil of the correct viscosity suitable for wet clutches. Works for me.
But to each their own.
Thanks for posting.
28/05/2020 08:11:19 UTC
Ren - The Ed¹ said :-
Holy cow Batman! It's like a veritable rainbow of coolants but I'd like to point out that not everyone follows the colour codings, not even close. I have "conspiracy theory" friends who drive me mad then I see things like this and I can't help but think "yes, they are out to get me".

I suppose the truth us 5w40 in the vespa and green coolant not blue (after a good flush) won't kill the bike, ahem, immediately. It'll boil down to longevity, longevity way after the warranty has expired. That water pump that might have lasted 80,000 miles is starting to weep after 55,000 miles. Those valve guides that might have lasted 100,000 miles only made it to 75,000 miles.
28/05/2020 08:18:50 UTC
Ian Soady said :-
As Ren says the colour doesn't actually tell you anything and the manufacturers are very coy about actually putting the real type on the packaging. You need the product data sheet and even those are getting hard to find. Silkolene used to be quite good but I see from their website that even they have stopped supplying the information.
28/05/2020 09:43:34 UTC

Post Your Comment Posts/Links Rules



Add a RELEVANT link (not required)

Upload an image (not required)

No uploaded image
Real Person Number
Please enter the above number below

Home Ren's Biking Blog

Admin -- -- Service Records