FE/FC Looking for some FE501 Feedback

Spent some time recently installing a 4.1 gl Acerbis tank on my FE501. The tank drops on without issue and has no interference issues at all. The only issue is that the Husqvarna seat pan must be trimmed approximately 1" from the front end to fit the contour of the Acerbis tank (which is manfufactured for the 2014 KTM 500/350) Will be swapping out some plastic as it arrives and also with an all black Seat Concepts saddle.

Here is the tank test fitted




With the stock seat pan and cover.. a bit too long




With the seat cover removed and the seat pan trimmed back to fit the contour. The front of the seat will still be held by the front guide.



Although the seat pan has been shorted slightly it will still work fine on the stock tank.

Considering my 501 continues to melt my right side radiator shroud and I would like extended fuel range, this fuel tank may be a good option to kill 2 birds with one stone. A buddy of mine just put a black tank on his 350 and swapped fenders to black as well. I looks pretty good and beats the pumpkin look. I may go translucent on mine though. Not sure. have you kept track of your fuel mileage yet? I leave for the ADV rally Friday morning for 8 days of fast open trails and typical days of 150 miles. I'm hoping for 40-45ish like my 310 regularly got.

Ya apparently 10k doesn't buy much these days...

I think because the hot air from the fan exists where it does on the shroud, it melts the adheisive on the decal and it starts peeling. I removed the shroud and lined it with heat reflective matting but it didn't help. The actual plastic is showing signs of melting as well and I have a very form fitting shroud now... I don't have this issue if I'm just cruising around dual sporting but once I hit the tight woods the heat is on, BIG TIME. The reflash did nothing to resolve the issue either. That was a waste of $ but what's done is done. I do have a fancy 3 position trail tech switch on my bars now.

I did some poking around on the berg forum and found a few threads addressing this exact issue and sadly in the end they all ended up selling the bikes and going to another brand. I hope a Beta isn't in my future because this freakin bike was costly... I leave for the ADV rally tomorrow night for 9 days of heavy off road riding(and some drinking too, hehe) so I don't anticipate overheating issues due to the open type trails. Realistically I'll be putting on 30 hours next week. Plan to change the oil halfway through the week to be safe.
On a lighter note, my local dealer, whom I purchased this bike from, came through in a pinch with a replacement front fender brace nut today. They yanked one from a FE250 on the floor and I just payed for a replacement. Problem solved.

Yes. I did order a radiator hose($10)for a KTM 450SX that replaces/bypasses the radiator and plan to install that when I get it. I will need a plug/cap to cover the small outlet on the right side radiator though. I see they sell the plugs at Samco but hope to be able to source one locally from an auto parts store. Doing this may help increase coolant flow. The threads I read all said they tried eliminating the thermostat too and it didn't fix the issue. I don't give up easy though.

Have you removed the side tank plastic to check for any issues with the fan alignment or obstructions in air flow?

What map was on your ECU before Halls flashed it?

How did you break the motor in during the first hour?

How many hours are on your bike?

Did it run hot before you pulled the valve cover and (did you adjust the valve lash)?

Have you tried 10w-60 full synthetic to rule out the oil?

Are you using non-ethanol fuel? 91 octane?


just try to help....

For what its worth.. my two friends with KTM 500 excs seem to have their fan running more often then my FE501.

Also there does appear to be more of a gap between the inside of the Acerbis tank and the radiators. Certainly enough to run a pair of radiator guards.

It has ran hot from day one. Halls flashed it last week with 6.5 hours on the bike. I have no idea what map comes from the factory. I was told it comes with a 500 XCw map but I can't know for sure. I just readjusted the valves to the proper clearances last Thursday and only rode the bike for 30 minutes since. It does seem better since the valves were checked and set properly. I was running 100 octane VP ethanol free fuel. I also tried 93 pump gas with ethanol and it didn't change the heat issue. yes I've had the tank, radiators and shrouds off, everything is normal there. I'm running Evans waterless coolant which is second to none. Stock louvers on the rads. If I don't ride single track the bike runs cool, it just doesn't like the woods I guess. No I haven't tried running 60 weight oil, I ran 10-50 Motorex synthetic until now.

Have you tried removing the right side tank cover and doing a short woods ride (I assume you mean single track?) to determine if that improves air flow and solves the problem?

IMO I think you are wasting your money on the 100 octane stuff...The compression on the engine doesn't warrant it.

What gear set is on your bike and when riding single track are you staying in first gear?

Did you break the engine in doing single track?

Just seems odd since mine doesn't melt the plastic or tank decal and I've been doing some single track stuff but I am moving in second most the time.. might be easier single track than what you are riding. I noticed that the Acerbis tank has two open vents for expelling air while the stock tank plastic only has one. In addition the KTM 500 tank panels seem to offer improved air flow behind the radiator.

Stock 13/50 gearing. I'm carrying 2nd gear most of the time. Lots of rooted out hill climbs and logs When in the open I hit 3rd for a short burst but then back in the trees I go. My plastic really isn't completely melting, more the decal on the black part however upon removal of the side shroud I did notice some signs of the plastic getting discolored. I'll snap some pictures after my trip and hopefully I'll have a better idea of how it performs on more open riding.
FYI, I broke the bike in just riding around near my house in some open fields and pavement. I heat cycled it and worked through the gears like they recommend for the first 2 hours which was spread over a couple of days. I runs really strong now but the excess heat really caught me by surprise. I think it has to do with the way the fan blows the heat out the opening in the shroud which is directly on my right knee. I ride up on the tank and have long legs so I'm in the direct line of fire. Don't get me wrong this bike is still amazing but I hope this heat thing gets progressively better with more hours on the bike.

I am running 10w-60 in her at the moment and as reveille has said when on the open trails barely any heat and the fan normally doesn't even come on. As soon as you get into the tricky stuff fan is on and she is getting really hot! Can't say it is unrideable though or my shrouds are melting, but I came off a ktm 350 with no fan and it got no where near as hot. I live in a tiny little town in the middle of OZ where it can be 40'C for weeks lucky it isn't summer yet!

My FE501 evolution continues

Fitted my Seat Concepts all black saddle with carbon sides and non slip seat surface.
Added some larger (primarily wider) billet foot pegs that offer improved stick over the stockers.
Replaced the factory yellow fork guards with black Acerbis copies.

I have a full black Acerbis plastic kit but I'm not so sure I like the shiny black look after trying the right rear side panel over the exhaust. Almost wish I could find a flat black plastic kit. Haven't decided if I want to black it out or do a mix and match.. white/black combo.

The Acerbis tank does offer multiple cooling ports behind the radiator and also offers more clearance on the sides between the radiator and tank which should improve air flow in slow moving situations.

Cockpit view














with black side panel installed



The pegs

I would do the Kardashian treatment to it and go completely black.

For those thinking about going to a Acerbis tank I've taken a few more photos showing what the slightly trimmed seat pan and Seat Concepts saddle look like with the stock tank. IMO the bike looks much better with the black fork guards and all black seat when fitted with the stock tank.








Why is it that new bikes get preferential treatment in the garage??

I read somewhere guys with Berg where running a different fan switch. It turned on a lot cooler than stock, like 170-180.

Yep. Napa p/n 143 5033.
Turns the fan on at 203f vs. 212f

We finally tore our FE501 down for a rebuild at 59 hours of Ty Davis on it. Tossed a micrometer on the rod journal and for the first time ever, no wear. 12 KTM's rebuilt last week, all requiring new journals and rods, ours, not even a blemish. Our new 501 racing engine is almost complete and ready for V2R. Can't wait to play on the dyno, definitely the most powerful Husky we have built to date.