FE570 with a reservoir tank, different rad cap?

keener · Sep 27, 2016

My 570 came with a 1.8 cap. Not sure what the stock should be. It occasionally boils in hot single tracks.

I made a simple reservoir/expantion system. It fills up the expansion tank when hot but never pulls it back in the rads when it cools down.

Question is that should I be using a lower pressure cap like 1.4?

And are all KTM caps the same except the pressure rating? The reason im asking is thay someone posted something about an extra vacuum valve in the centre some cap that allows coolant go back in ,but I can't confirm if my 1.8 cap has that or not. They all look the same!

giovosc · Sep 24, 2017

Have you installed the Fan Kit?

rumpel · Sep 25, 2017

better install 1,8 bar cap

jdubb75 · Sep 25, 2017

keener said:
My 570 came with a 1.8 cap. Not sure what the stock should be. It occasionally boils in hot single tracks.

I made a simple reservoir/expantion system. It fills up the expansion tank when hot but never pulls it back in the rads when it cools down.

Question is that should I be using a lower pressure cap like 1.4?

And are all KTM caps the same except the pressure rating? The reason im asking is thay someone posted something about an extra vacuum valve in the centre some cap that allows coolant go back in ,but I can't confirm if my 1.8 cap has that or not. They all look the same!

From what I understand, the stock cap is not designed to allow coolant back in from an expansion or overflow tank. It's possible to get one that is, but I can't remember where. I actually read something about it not too long ago, but can't find the info. You might try asking on the 70° thread on Advrider. I think someone there might have been talking about it.

I installed a TrailTech digital fan on my 390. It allows you to set the temp when the fan kicks on. I have mine set at 195, but haven't had it on any singletrack since the install. The fan I installed was the FN8 model.

Not sure why it's rotating my pics, but you get the idea.

keener · Sep 26, 2017

Interesting that you responded now because I just started experimenting some more just last week.

I added a proper reservoir tank and tried using a 1.4 bar cap from my KTM 990 that has a expansion tank of course.

I got coolant all over me while riding lol...I think my old 1.4 cap is faulty. I'll try a new one.

Looking at 1.4 and 1.8 caps I don't see any difference. We'll see what happens with a new one.

jdubb75 · Sep 26, 2017

keener said:
Interesting that you responded now because I just started experimenting some more just last week.

I added a proper reservoir tank and tried using a 1.4 bar cap from my KTM 990 that has a expansion tank of course.

I got coolant all over me while riding lol...I think my old 1.4 cap is faulty. I'll try a new one.

Looking at 1.4 and 1.8 caps I don't see any difference. We'll see what happens with a new one.

Oh wow, I just realized this thread is a year old. Well, post up some more test results when you have time.

keener · Sep 28, 2017

jdubb75 said:
Oh wow, I just realized this thread is a year old. Well, post up some more test results when you have time.

I installed a tested 1.4 cap on and result was not so impressive.

I filled up the rad to 10mm over the fins and rode in the city trying to heat up the bike. Cools came out and filled up about half of my expansion tank after 15minutes of riding. BUT it didn't get sucked back in to the rads when bike cooled down.

I'm thinking may be I should fill up the rads to the brim and remove all the air from the system like my 990. And full up the expansion tank to 1/3.

May be, the air gap in the rad is preventing the coolant get sucked back in.

Thoughts?

pjk380 · Sep 28, 2017

Parts fische shows 1.8 bar cap for 70 deg bergs and newer ktms, bergs, huskys, 2 stroke and 4 stroke. My older ktm 380 2 stroke is using the 1.4 bar cap. I've had the RLRproducts.com coolant recovery tank on my 380 for years. It works as advertised. The coolant level is always at the top when I pull off the cap to check the level. Any coolant tank should work the same way.

If you are doing any single track, tight twisty riding you should have a fan installed. I dont have a coolant tank on my FE450 but have a fan kit. The fan has saved my 450 from boiling over plenty of times. For tight twisty riding I definitely recommend you get a fan kit.

keener · Oct 25, 2017

pjk380 said:
Parts fische shows 1.8 bar cap for 70 deg bergs and newer ktms, bergs, huskys, 2 stroke and 4 stroke. My older ktm 380 2 stroke is using the 1.4 bar cap. I've had the RLRproducts.com coolant recovery tank on my 380 for years. It works as advertised. The coolant level is always at the top when I pull off the cap to check the level. Any coolant tank should work the same way.

If you are doing any single track, tight twisty riding you should have a fan installed. I dont have a coolant tank on my FE450 but have a fan kit. The fan has saved my 450 from boiling over plenty of times. For tight twisty riding I definitely recommend you get a fan kit.

I put the 1.8 cap back on and tried again. This time I filled up the rad to the top AND bled the system. I squeezed the pipes, shook the bike and all that jazz to take all the air out.

It worked.

And yes I'm using RLR reservoir.

The trick was removing the air in the system. The 10mm air gap is not neccesaary with a reservoir tank installed.

Search

Search

FE570 with a reservoir tank, different rad cap?

keener

giovosc

rumpel

jdubb75

Attachments

keener

jdubb75

keener

pjk380

keener

Similar threads

Register CTA

Recent Discussions