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[jotjotde]

I have the R&G radiator guard installed for some time now and I would like to share my experience.

https://www.rg-racing.com/browsebike/ENERGICA/EVA_RIBELLE/2021/RAD0282/#

The quality is surely good, the guard is fixed well and there is no danger of losing it.

The only problem appears if you are riding the bike energetically 
More detailed: Riding in SPORT mode and doing several high power accelerations above 160 km/h, the battery temperature symbol will turn from green to red and the bike will go in limp mode.
That can happen even at moderate temperatures (16 degC).
After going in limp mode for one or two minutes, the temperature is back to yellow or even green. Then the limp mode is automatically deactivated again.
Happened to me on the racetrack (not so nice) and on the highway while overtaking (nearly soiled my pants).

In my opinion this is caused by the restricted cooling due to the radiatior guard.
It appears to me that the battery temperature indication is not really coming from the battery. I suspect it is more the coolant fluid coming from motor and inverter.
Probably the high ampere riding heats up the coolant and the heat sink is not sufficient.

[Demoni]

This is incorrect the battery temp icon indicates your battery temp. Refer to your owners manual for specific temps for each color but it will show red above 55*C. At that point the bike will restrict power to prevent the battery from overheating.
With that being said the bike also has sensors to monitor the inverter and motor temps (not shows on the dash). If the temps of those devices are too high it will also restrict power to prevent over temperature situations.

So it is possible the guard is restricting air flow enough to cause the bike to hit limp mode but now for the reason you indicated. Remove it and see if the issue goes away?

[jotjotde]

Thanks Demoni for the quick reply!

OK, I was wrong then - just tried to find an explanantion for what I experienced.

No, I have not tried the bike without the guard yet. I just wanted to share this experience early for other users so they get a heads-up that something like this can happen e.g. while overtaking.

[Pard]

Radiator guards don't block that much airflow.

I get the yellow battery temp warning when pushing the bike as well, never triggered a limp mode from it though.

Can you keep the engineering screen open while you ride to see what temps you are running? 

If it is hard to see while riding, you can film it.

Once again, so great to have @Demoni active in the forums!  No better resource for accurate information on the planet when it comes to these bikes.  Thanks for taking the time to chime in!

[DerKrawallkeks]

jotjotde, the radiator does not cool the battery but only the inverter (maybe the motor in some models). If you read again what Demoni wrote, that will make more sense now for you.

I am confident that the metal guard can not cause any significant impact on the battery temp.

Thanks to Demoni for being active here!:) very valuable

[Fred]

No, I have not tried the bike without the guard yet.

If you've not tried the bike without the guard, then it's a bit of a jump to conclude that the guard is the cause of the problem.

[jotjotde]

The guard can indeed slow down the airflow through the heat exchanger.
If the air velocity is reduced, the convective heat transfer is also reduced, roughly by the square root of air velocity. That means at half velocity, convective heat transfer is reduced by about 35 %.

[DerKrawallkeks]

Your battery is not liquid cooled.

[Pard]

The guard can indeed slow down the airflow through the heat exchanger.
If the air velocity is reduced, the convective heat transfer is also reduced, roughly by the square root of air velocity. That means at half velocity, convective heat transfer is reduced by about 35 %.

Good reference data.  That is significant.  Curious to see what happens when you remove the guard.

[DerKrawallkeks]

This is not reference data? He's just quoting the theoretical formula for heat transfer.

[Pard]

This is not reference data? He's just quoting the theoretical formula for heat transfer.

Well, useful info in any case. 

[Specter]

Ive only had my temp indicator go yellow a few times on my Ribelle and that is when I was absurdly stupid, as in WOT for a dozen miles or so on a nice sunday morning on an empty interstate.

The race bike I may tap it once the months start getting hotter but i never seen any issues with approaching orange or red.  I think the worse I heated my motor / inverter up was like 160 degrees and that was  on a 90 degree day pushing hard on the back side of Jennings for many laps.

With the radiator guard.  Why do you need it?  Yes in theory to protect the radiator but so far, I have not seen anything being brought up in there to cause an issue.  Even on the race track, even riding off line and harking up a bunch of boogers, I don't see much crap getting stuck in the radiator area.

Id take that guard off then see how it behaves, I bet the problem goes away.  That radiator, isn't very big, not that it HAS to be but, given all, it don't take much inteference with airflow to really put a damner on it's efficiency

Aaron

[Demoni]

With the radiator guard.  Why do you need it?  Yes in theory to protect the radiator but so far, I have not seen anything being brought up in there to cause an issue.

Since the radiator is mounted so high up on Energica bikes the danger of a rock being kicked up by the front wheel and causing damage is very low. Using a guard just provides a extra layer of protection.
Some race series require a guard be installed as a blanket safety item. Likely because other bikes with rads more in the danger zone have been damaged in the past.
When we raced the EVA in CRA (California Roadrace Association) we needed a guard to pass tech. I fabbed one out of some wire mesh we picked up from a hardware store.

[DerKrawallkeks]

Just some random "reference data"
I had my Eva overheat at 20°C recently while going about 5-10 km/h up a mountain during a bicycle race.
I did not expect that and almost couldn't believe it. It's a 170 HP bike that overheated at 1 kW:D
But it makes sense considering it was pushing significant phase current regardless of the speed (all that with no airflow).

Don't take your energica to uphill bicycle races unless you added a fan for the inverter radiator.

[Sklith]

I've done a lot of hard riding and DCFC sessions in the Georgia summer (90F-95F) and the battery indicator never gets worse than yellow. My bike has the smaller battery so maybe it rejects heat better than the 21.5kWh ones.