Article by Michael Lindsay // Photos by GuyB

The KTM 350 SX-F has always been an interesting bike to me. If you're not worried about racing against a batch of torque-monster 450s, it can be one of the most fun bikes on the market to ride. But if you’re racing against 450s, you may be swayed away from the 350. Joe Schutz, owner of Quick Wrench (and previous wrench for Nico Izzi from 2001-2006) also enjoys the KTM 350, but wanted to address a few things to make it into what he considers the best vet bike. Thus, the Quick Wrench 350 was born.


Quick Wrench KTM 350 SX-F Features:

  • GET GP1 EVO ECU and the addition of a second fuel injector in the airbox with custom PR2 mapping.
  • PR2 suspension re-valve, with PR2 oil lockers and linkage.
  • Ride Engineering triple clamps with rubber bar mounts, and CRF axle adjuster kit.
  • Complete Hinson clutch and cover.
  • Custom black FMF 4.1 RCT carbon/titanium exhaust.
  • Raptor titanium footpegs, protected by Peg Armors.
  • Dubya wheelset, built with Dirt Star rims, Talon hubs and Galfer rotors, mounted up with Dunlop MX52s.
  • Fastline Graphics with MotoSeat seat cover.

First Impressions:

A quick walk around the bike revealed Joe's longstanding relationship with PR2, as both the suspension and performance mods involved their assistance. On the performance side, the biggest upgrade was GET's GP1 EVO ECU and second fuel injector. The ECU allows for a wide range of control, including the ability to control the second injector and adjust the mapping from your phone via Wi-Fi. The only other engine-related mods were kept to a FMF 4.1 RCT and a full Hinson clutch.


With the bike mapped to VP's MR Pro6 fuel, it produces around three more horsepower at 5,000 RPM and finishes out with six more horsepower with rev limiter raised 200 RPM. That's a pretty good chunk of power, considering that nothing internal was changed other than the clutch. The second injector that’s placed in the airbox allows for a much higher rate of fuel, and combined with the right mapping, can equal some big power gains. By doing this, Joe has been able to keep the bike extremely reliable and eliminate changing out parts that would be compromised by more compression or other internal changes.


Suspension tuning duties were handled by PR2 Suspension's Chris Durham, who is Darryn Durham's father. Outside of a re-spring and re-valve service, PR2 also installed their oil locks, spring perches, and complete linkage. All of these items are built in-house and tested by PR2 themselves, allowing them to make as many changes as they like until the product meets their needs.


On the Track:

Once the bike is out and rolling, it feels a bit like the standard 350. Stock, the low-end power is a snappy, but easy to ride. This builds progressively through from the mid into top-end, which is rewarding. But to keep it in that top range, you tend to over-rev the bike a bit and shift often. However, the first time I rolled out of a corner and pointed the Quick Wrench 350 up one of the massive hills at Glen Helen, the gains became instantly obvious. With the changes, the bike retained its easy to ride low-end, but builds power much more rapidly through the range. This increased mid-range made it much easier to leave the bike a gear higher, creating an easier to ride but even faster bike that required much less shifting. Even better, the massive top end gains were amazing when screaming the bike up the long uphill pulls.


A very interesting feature was the ability to change the mapping through a phone via Wi-Fi. After my first outing on the bike, I found that the bike had a small hiccup when you'd roll back on the power after a pull up one of Glen Helen's many hills. Joe and I agreed to lean it out just a tad bit as there was too much fuel left after I backed out of the throttle. Joe whipped out his phone, and about two minutes later I was back out on the track with the bike running perfectly. With the right knowledge, this system can be quite amazing due to the ease and reduced time required to make small changes from track-to-track.


The suspension was sprung for Joe at around 190 lbs. This had me worried, considering I weigh around 155 lbs with rocks in my pockets. Was the suspension stiff? Yes a bit, but this was to be expected considering our weight difference. Surprisingly, the bike was still fairly comfortable to ride around Glen Helen's National track. How's that you may ask? The bike was very well balanced; the settings, linkage, and Ride Eng. clamps all complimented each other very well and left a predictable ride. Front and rear were actually very plush initially, but then the weight difference became apparent as it got deeper in the stroke. Thanks to the consistency front and rear though, I never found myself thinking that one end was overriding the other.


Final Thoughts:

This KTM 350SX-F has got to be one of the best thought out bikes I've ridden in quite a while. It keeps the pure fun of riding the 350, while getting the extra boost of power needed to take the fight to a field of 450s. All this is accomplished while still keeping the engine nearly stock and extremely reliable. The power gains were instantly noticeable in mid-to-higher RPMs, but still left the bike very rideable. Beyond that, the mods were kept limited to parts needed for an excellent ride and durability reasons, such as the Hinson clutch and Dubya wheels. If you're looking to add some serious power without opening up the engine, consider giving Quick Wrench a call.


Quick Wrench offers a variety or services; from engine and suspension rebuilds, to race bike prep and custom bike builds. You can check them out on Facebook or call them at (608) 807-6795.

What Does it Cost?

  • GET GP1 EVO ECU: $999.99
  • PR2 Second Injector kit: $799.99
  • PR2 Suspension: Re-valve forks $194.95 and shock $189.95, Fork springs $109.95 and shock spring 114.95, Oil locks $49.95, Spring perches $119.95, Complete linkage $399.95
  • Dubya: Wheelset/with sprocket and brake disc bolts: $1290.00
  • Ride Engineering: Triple clamps $529.90, Bar mounts $99.95, Axle blocks $54.95, CRF axle $44.95
  • Galfer: Front brake rotor $165.00, Rear rotor $81.95
  • FMF: 4.1 RCT exhaust/ with carbon cap $499.99

About the Test Rider:

Michael Lindsay - is a born-and-raised moto freak and gearhead from the heart of motocross in Southern California. First swinging a leg over a bike at the age of five, he immediately caught the racing bug, spending nearly every weekend behind a gate… and a lot of time on the couch while injured. While swinging back and forth between moto and the off-road scene, giving him a wide range of experience on the bike. Of course, all of this led to one thing: Lindsay loves working on his bikes almost as much as he loves talking about them. When he’s not in the Vital MX forum or writing his latest product review, you can find him out at the track taking dirt naps, snapping some pictures, or drooling over the latest parts for his bike. With an outspoken personality, gearhead background, and as Vital MX’s guru for product, Michael is here to share his unbiased opinion.

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