[ronseal90]

So I purchased a new 790 duke yesterday and drove around 100km with it. I was riding with some Levi jeans on and after about 30 minutes I can feel the heat from the engine getting unbearable, I just thought **** this is hot and can feel my left leg stinging anyway so I got home later to find that my left leg looks like it's been sunburnt and I put some aloe vera on it and in the morning it's gone down a lot the redness but I've got blisters from the burn now.

Now I don't know much about bikes, to be honest, other than they are lots of fun, my previous bike was a 390 and I got bored after a year and wanted something with a bit more power so decided on the 790. On the 390 I could hug the tank with my legs and never experience any sort of burning wearing the same jeans I wore yesterday.

So as to my questions. Is this normal and I just need to buy proper protective trousers to prevent it happening again? Or does my bike have a cooling problem or something? I did have one of the black bits in the bike pop off after a few kilometres from a stop light when I webt off (see pic below as I don't know the correct terminology to explain)

It wasn't like I was hugging the tank or anything and as said it was fine for 30 minutes just after something happened and it was like heat from engine x100. I've ridden it since and the same thing, starts off okay then after 30 minutes it gets really really hot.

after the first ride with jeans on

the following morning

the area where my leg is getting burned, but as said I'm not hugging the tank or anything

the black thing that came off

Thanks in advance for any help or suggestions, I didn't buy it from a dealer so it's not as simple as go back to the dealer and get them to check it and I know nothing about repairing or fixing the issue another way.

 

[J D]

knarly first post, lolZ

Where are you located that it's so dang hot?

The only time I burned my leg was this past April in Florida, riding a friends Harley, with shorts on, (total fool move), and seared my leg against the exhaust pipe..

 

[EvansB2]

Crazy! What temperature was it outside? What was the temperature gauge saying on your dash (how many bars)?

 

[ronseal90]

It was about 28-30 degrees celsius outside, iirc the dash said about 33 degrees , can't remember how many bars the engine was showing heat-wise, I didn't get any sort of temperature too hot warning from the dash though when I was riding which it should have done if the bars were all full or at 8 right?

I just know the bike was sitting with the seller unused for about 10 months, the guy had it ages just sat in a warehouse and is a 2018 model if that helps. Definitely, brand new though could tell from the bad smell of the engine (sign of a new bike) and 0km on the meter and not a mark or scratch on the bike, I did have to put together the electronics in the back seat to get it working as he'd switched it all off so couldn't power it on. I think I did it all right. Unless I missed something.

Here is a pic of inside the back seat

Could it be perhaps the seller did something else and turned off something to do with the cooling system I'm missing? Again apologies if these sound like stupid questions, I just have very, very limited knowledge of the bikes and I live in China with my wife who knows nothing and had to sort out the purchase for me as I speak no Chinese and it's her native tongue and live like 600 miles away from the nearest KTM shop lol so that's why it not so easy for me to go to the shop.

Edit: If you need me to check anything else or show any pictures of specific areas of the bike that could help determine why my leg is going to get burnt every time a do a 30+ minute trip, then let me know I can take some in the morning when better like

 

[EvansB2]

That’s crazy. 33 isn’t that hot.

Have you checked that there is coolant in the reservoir? Perhaps the engine was running hot.

I’m stumped.

 

[Pgm]

Strange one this, I’d think if the engine got so hot you burned your leg you’d have engine damage.
There’s no chance you could have spilled something on your jeans before you set off?

 

[ronseal90]

Really appreciate the fast replies guys

That’s crazy. 33 isn’t that hot.

Have you checked that there is coolant in the reservoir? Perhaps the engine was running hot.

I’m stumped.

Could you explain how I can do that? (sorry I'm a complete noob to bikes) I can try in the morning if I know what I'm looking for as now pitch black no light so doubt it would easy to check right now. So if you wouldn't mind explaining the process that would be great.

Strange one this, I’d think if the engine got so hot you burned your leg you’d have engine damage.
There’s no chance you could have spilled something on your jeans before you set off?

Definitely there was nothing spilt on my jeans before the first ride. Plus I took it out the next day (today, after I had the blisters), wrapping a bandage around the blisters to try to protect and could feel the burning again and the engine getting mad hot again after 20-30 minutes just like the first ride so just went back home straight away otherwise god knows how many blisters I would have come back with this time haha.

 

[Pgm]

I’ve ridden mine in jeans and joggers and haven’t experienced what you’ve gone through, hope you find the reason why quickly.

 

[EvansB2]

For how to check your coolant level, download the Owner's Manual:

https://www.ktmshop.se/documents/19_3213925_en_OM.pdf

There's a lot of good information.

My pet theory about your bike is that it has very low coolant and is running extremely hot, but that's just a guess. Are there any motorcycle shops in your area that could check for you?

 

[Chic]

Well, welcome to the forums!

My bike gets pretty hot when I am sitting in traffic.....max it hit was 5 bars though. I can feel the heat coming up from the engine and it gets real hot, though not nearly hot enough to do that! I typically ride in jeans to and from work so I can relate. Just curious, how tall are you? Based on the location of the burns and the blisters (right on the inside of your knee), it seems to me that your knee fits right into that little alcove where you have circled, which is probably real **** hot, especially at temps. Understand you aren't hugging the tank, but even if your knee is pushing into this area, I could see how it could be close to touching the top end.

If you have coolant then you shouldn't be running that hot, and even without coolant, if you are moving, the engine temp should not get that hot.

 

[GLantern]

If it was sitting and all that stuff was disconnected with 0km on the bike it might have never been setup right. Definitely check that coolant level and report back!

 

[Chic]

To answer the question of how to check coolant, in the very front right behind the front wheel is the radiator. As if you are sitting on the bike, the top right corner (behind the right cowl) is the coolant cap. When the bike is COLD, unscrew the cap and see if you see any coolant. If not, there isn't enough in it!

 

[Mullasci]

I was riding with 35C here in Italy recently and I could clearly get the hot air when going slow or stopping, but nothing that would burn me like this: my previous 1994 CBR600F2 was way hotter.

You mentioned you didn't touch the tank, so it looks like you might have some hot vapor coming out.
Could be a defect in the head gasket letting steam out.
If your coolant level is still within limit you can start the bike and leave it running then check if there is any hot leakage.

 

[Chic]

I was riding with 35C here in Italy recently and I could clearly get the hot air when going slow or stopping, but nothing that would burn me like this: my previous 1994 CBR600F2 was way hotter.

You mentioned you didn't touch the tank, so it looks like you might have some hot vapor coming out.
Could be a defect in the head gasket letting steam out.
If your coolant level is still within limit you can start the bike and leave it running then check if there is any hot leakage.

Great point!! That didn't even occur to me! I would imagine though you would hear it and feel performance issues, and if it's big enough, to much blow by that it wouldn't even start.

 

[J D]

Perhaps visually check the level in the compensator tank/overflow tank.

Not always the easiest to see, however, if it’s empty, then I’d check the radiator level.

So, being this was a month ago, how did it work out for ya?

 

[QCS]

I am doing a lot of riding at around 90F-100F ambient, here around Charlotte. Bike gets hot, but not that much. Also, my knees don't even get near the exposed parts of the engine.

 

[colombo]

@ronseal90

Did you figure out the issue?

 

[J D]

haha, sorry, had to..

 

[rft]

I think we are missing a few obvious points here, 1st the black "round thing" is just the frame plug for the top shock mount.
2nd there are 2 obvious things that can cause this problem, the radiator fans or the coolant level, both are easily checked.
If you don't know how to check the fan or coolant take the bike to a dealer, you are running the serious risk of cooking the motor.
As for heat from the motor I think the 790 is one of the coolest bikes I have ever owned and we get some pretty high summer temps in Australia.

 

[JP]

I have had my pants burned twice from the exposed exhaust pipe near the foot peg while standing next to the bike. But I guess you expect that with a "naked" bike. I am looking into finding a shield for that portion of the bike to prevent any burns. The bike does get pretty hot, but never over 5 bars.