FE/FC FE 350 Mods

Let me preface this by saying that I don’t profess to be any kind of an expert on this subject matter nor do I share what I’ve done to my bike as an example of what others should do to their bikes. That is a personal preference and up to each individual and their riding needs. However, as I searched for modification information for the new FE350 (both on line and at the dealers) I found very little information because they are so new. Given that, I thought I’d take the time to share my experience with this bike that perhaps others may find some part of this helpful.

I Bought the bike new about 3 months ago.

Motor: Stock power was strong in the upper RMP range. Found the power too weak for my preference in the low to mid RMP range. Added a full FMF exhaust system; had bestdualsports do their “magic mod” to my ECU and installed their “Grunt.” These mods did make the bike stronger across the RPM range, but they only made a “small” improvement in the bottom and mid RPM range. It wasn’t nearly what I was hoping for. I installed the 390 big bore kit from Thumper Racing along with the KTM 350SXF water pump impeller kit for added cooling. The 390 kit provided that extra boost in the low and mid RPM range that I was looking for without sacrificing any of the power in the upper RMP range. Thumper racing provided a new map for the 390 kit that worked great. However, you cannot install it on top of the stock map. The European map must be installed first and then the Thumper Racing map can be installed. The stock map is locked and does not allow adding the Thumper Racing map. I also had to undo the “magic mod” after installing the Thumper Racing map so it didn’t run too rich. With the 390 kit installed I was able to go to a 14 tooth front sprocket which provided a gearing ratio that works better from my riding area (Utah with single track, but also open desert as well). It still has sufficient power in the low to mid RPM range in all gears. It now has a top speed of 90 MPH, pulls long steep hills strongly in 2nd gear, and handles tight, slow technical sections in 1st easily.

Suspension: After breaking in the suspension I found the forks to be too soft particularly in the mid stroke. When driven hard and committing weight to the front wheel the forks would tuck and dive dramatically. Not a good feeling. I had PG Suspension redo my suspension. They replaced the stock .42 fork springs with .455 springs and re-valved both the forks and the shock. We kept the stock shock spring (5.6). I weigh 175 lbs. This made a huge difference. In hindsight this is the first mod I would do to the bike if I was doing it over again.

Lighting: The stock headlight is extremely poor. It will get you back home in the dark, but you cannot ride at speed with it. I added the Baja Designs Squadron light and it works great. The stock electrical system handles the Squadron just fine. However, Baja Designs does not yet make a mounting plate that allows the Squadron to mount inside the stock Husky faceplate. I bought the mounting plate they sell for the 350 KTM model and then modified it to fit. It took some drilling and cutting and filing on the KTM mounting plate to make it work, but it turned out nice. I also installed a dimmer switch from Baja Designs for the Squadron. The Squadron is so bright there is no way to ride on the street at night without dimming it. I also installed the “Just Barely” street legal lighting kit from Ryco Motorsports Inc. It was “plug and play” and is a nice product.

I’ve installed other mods that most are familiar with. Cycra hand guards. Scotts Damper (sub mount). Low rise Evo bars (to help offset the sub mount). Tubliss system in front and rear tires. TMD skid plate (which fit great and also worked with the oversized water pump impeller kit). BRP vibration reduction bar mounts. Rekluse 3.0 core EXP auto-clutch and Pro Moto rear disk guard.


At this point I couldn’t be happier with this bike. I hope this was helpful.

Why didn't you just buy a 450? would have been a crapload cheaper
looks nice though

Good info. I was not happy with the stock gearing on mine however I went the other way and went up one on the rear. 1st is completely useless in stock form so figured I'd rather feel like I'm in the right gear from 2nd on up than have 1st and feel a gear to high everywhere else.

I totally agree on the stock gearing. Good idea to go up on the rear sprocket and use 2nd. I would not have been able to go taller on gearing without the added power from the 390 kit. Here in the West we have a lot of wide open area where it is easy to reach top speed on the bike for sustained periods of time. The taller gearing helps in these areas.

Great report and some very useful info there.
By the way your bush weapon looks a cracker.

Thank you for the effort and sharing.

Hey I just bought the 14 350 as well and have the same complaint about lack of grunt, and I just came off a 450 xcw. How do you like the thumper 390 kit and are you using the fmf pipe with it. Let me know i would like something a little closer to a 450 but just not a 450...

I understand what you are saying. I too was riding a 450. I like the 390 kit. It is still no 450, but then again it is not intended to be. However, with these mods the power is much improved. In stock form the bike felt close to a 450 in the upper RPMs, and more like a 250 in the low to mid RPMs. I was riding a Yamaha WR 450 before this bike, and I also have a WR 250 that my son rides. So that's what I'm making my comparison to. With these mods it now feels like I expected a 350 to feel. Low to mid RPM range is noticeably stronger than the 250, and the upper RPM range is very close to the 450. It's a really fun and easy bike to ride. I find I'm faster on this bike than I was on my 450. It handles much better and it now has sufficient, progressive power across the entire RPM range. Hope that helps.

I wonder if the same power improvement could have been achieved by cams and porting ?

Makes me like my 2 Stroke even more.....

You want wild? Two Honda CR500's mated together....
Apologies for the hijack!

How many KM/miles are you guys getting out of a tank on the 350's?
mate done 55km yesterday with a full tank and the fuel light came on

Now that's a 2 stroke. Awesome, who's the nut building that?

Probably some guy interested in hill climbs or road racing.

I think that equates to 88.5 miles ? That is really good. I am getting close to 30 mpg riding aggressive single track mountain trails

Hey cbs and HC experts, I'm new to the Cafe & to Husky's. I sold my 2012 WR450 and picked up a new FE350 for only one reason...moving that beast (the WR) through the tight woods single tracks and rocky hill climbs that we ride a majority of the time in the 100 + degree Fahrenheit temps here in N. Texas was a killer & I'm in shape...48yrs old, 6ft tall, 195lbs & work out 5 days a week. I was really reluctant to let go of that 450 bottom end power and the WR never gave me a single problem, but understood the benefits of my sacrifice (agility, more fun to ride in my geo, etc.), as the WR left my driveway on the buyer's pick up truck I couldn't help but be super anxious about my decision. Now I've only had the Husky for a few weeks, took it out twice, the first time was to break it in and get that first oil change out of the way, the second was a little bit more like my typical riding, but tried to keep the throttle at 75% or less. I installed a FMF Megabomb & 4.1 slip and EXP Core prior to taking the bike out the first time and as I suspected it was running too lean for the exhaust (hot and hard to start cold). My dealer insisted that it wouldn't be an issue even though my experience doing the same on the WR told me it would be. After reading through this & other forums I deduced that the answer was in getting a re-flash of my ECU with the EU Map...simple & cheap enough, except after a bunch of back & forth with my dealer they absolutely would not re-flash the ECU, did some more research on the Cafe, got a few names of places that would do it if I shipped it out and chose a very reputable one (a non KTM/Husky specific shop). When they received the ECU they called to inform me that they could not unlock it because it was the ECU that is used in the KTM EXC model, the owner said when I got it back if I looked at it I would see the sticker that says EXC (he was correct). The owner of the place was cool enough to offer me an adjustable ECU with 10 maps custom programmed for my bike and the ability to trim the fuel at Lo Mid & Hi RPM ranges for each map with a click of a rheostat at a couple of hundred dollars off and free shipping back with my OEM ECU since he committed to being able to do it when we spoke. Bike runs great with the new ECU, easy start, not as hot, no popping on deceleration and that was on the "Enduro" map which was much more snappy than stock on the bottom end (still no 450, but it's not a 450), I will try the "Aggressive Power" map next weekend if the wife lets me go play which the shop says will make a big difference even over the Enduro map.

I guess my questions are;

Has anyone else experienced their FE350 having a EXC ECU in it from the factory?
cbs, now that you have been off of the WR for a while, what do you find to be the advantages & how long did it take you to get used to all of the advantages of moving from the 450 to the 350? I'm trying to figure out what I have to look forward to.

Once I get the suspension broken in, I realize that I have to get it set up for my weight & riding...I know the rear spring is to light for sure, just looking for suggestions on what shops are reputable here in the states even better if in the DFW area.

Thanks for your time and looking forward to the responses. I have thick skin, so I'm ready for the lashings a new guy gets

Why didn't you spend $300 more and get a 450? I wish I did. I bought the FE-350 thinking it had "450 rivaling power", according to the Husky web site. Absolute nonsense! The FE-350 does not have the low end grunt of a 450. Not even close! Nevertheless, I'm happy with it as I've learnt to keep the revs high, but I do miss the low end grunt of a 450.
I won't spend thousands of dollars to get the FE-350 there though! It would be cheaper to sell it and buy a 450.
The FE-450 only weighs 2 lbs more than the 350, so weight is negligible.

Forget the ECU reflash, end caps, pipes etc. Save lots of money and just cut off the spark arrestor and the FE-350 comes to life.
I complained earlier about the lack of low end power on this bike compared to a 450, but no more!
Make sure you're allowed to ride without a spark arrestor in your area.
The bike has great low end torque now and wheelies in 3rd gear with clutching it up!
The difference in power without the spark arrestor is truly amazing.
It is a bit louder, but not too bad.