MXA TEAM TESTED: DR.D YAMAHA YZ250F EXHAUST

WHAT IS IT? The MXA test crew liked the improvements that the Yamaha engineers made to the 2019-2020 YZ250F engine. It got a new straighter exhaust port, higher lift cams, higher compression ratio, 44mm Mikuni throttle body, larger clutch plates, reconfigured engine angle, repositioned radiators and the electric-starter motor was moved rearward. The end result of the 2019 engine mods was more power from 10,700 rpm through the top end. The previous 2018 engine was strong on the bottom and in the middle, but was relatively flat from 10,000 rpm to 12,800 rpm. The 2019 engine is a top-end powerplant that plays in KTM’s high-rpm bailiwick, but gives up bottom and mid from off-idle all the way to 10,000 rpm to the 2018 YZ250F. The DR.D 2019-2020 YZ250F pipe does not focus on where the YZ250F is strong; it tries to fix where it is weak. Plus, it does it for lower cost than the competition. Good plan.

WHAT’S IT COST? $659.95 (stainless/aluminum canister/magnesium end cap), $912.95 (stainless steel/carbon canister/magnesium end cap).

CONTACT? www.dubachracing.com or (951) 808-1114 or (877) 382-2241.

WHAT STANDS OUT? Here’s a list of things that stand out with the 2019-2020 Yamaha YZ250F DR.D Racing exhaust.

(1) DR.D NS-4 pipe. The YZ250F pipe is the best-selling exhaust in the DR.D lineup. It is lighter than the stock exhaust and comes with durable 304 stainless steel tubing. With its welded construction (no springs), lightweight magnesium end cap, removable bolts (not rivets) at the outlet cap and a stepped perforated core for increased durability, the DR.D 2019-2020 Yamaha YZ250F exhaust system is set apart from the exhaust-pipe crowd by its simplicity and low cost.  

(2) DR.D power. Since Doug Dubach was the Yamaha test rider assigned to babysit the Yamaha YZ250F from prototype to production bike, he has more laps on the YZ250F than anyone on the planet. Doug is unique in that he doesn’t build a pipe with the idea of just chasing peak power and calling it a day. He prefers to spend time in the saddle and put the power where it does the most good. Because Doug took the time to ride and race the 2019-2020 Yamaha YZ250F, he knows exactly what the bike needs from an exhaust pipe. The DR.D Racing exhaust system did not change the high-rpm YZ250F into a midrange monster. Instead, it pumped up the existing YZ250F powerband from low to mid without changing the top-end hook. The added power from the DR.D exhaust helps get the bike out of the corners quicker, through the gears smoother and makes the transitional power more usable. 

(3) Track testing. On the track, test riders reported that with the DR.D racing pipe, they could accelerate out of corners quicker. Best of all, it produced a better powerband because it kept what the YZ250F had but filled in what it didn’t have.

WHAT’S THE SQUAWK? Be sure to coat the slip-fit at the mid-pipe with anti-slip compound to help it come apart after the first use. 

MXA RATING: This isn’t a dyno-queen exhaust system. This is a pipe for the working man built by the man responsible for the YZ250F in the first place. It delivers power where it can be used but without altering the character of the stock powerband.