Yoshimura Exhaust (From Suzuki's Promo Offer) First Impression

Yoshimura RS-4 Pipe On 2016 RM-Z250 Quick Test

Yoshimura RS-4 Exhaust and Hard Parts
This is the stainless steel and aluminum pipe with the Yoshimura hard parts that are part of a Suzuki promo.Photo by Pete Peterson

Suzuki asked us to meet them at a track so they could give us a Yoshimura RS-4 Stainless Steel/Aluminum exhaust and a handful of Yoshimura hard parts. Of course we said yes, and brought along our bone-stock 2016 RM-Z250 that started the day with 18 hours on the engine. Suzuki wanted us help spread the word about their current offer of the same package free to customers who buy a new RM-Z (RM85 guys get a Pro Circuit exhaust) before the end of March. Somebody then let it slip that the offer likely will extend until the end of April. We thought it would make a fun way to try the first mod many riders do when they get a new bike, ‘throw a pipe on it.’

The Yosh RS-4 Stainless/Aluminum is a two piece system, not a three piece; it scavenges the stock heat shield from the stock pipe, yet does include all the mounting hardware needed (spacers, bolts, and grommets). The fit was spot on and mount-up was a piece of cake. I rode the bike at my vet novice pace, and also had pro rider and DR tester Ricky Yorks ride the stock and ‘piped’ bike back to back at pro speeds. We both had similar impressions, even though Ricky rides in the high rpm and I ride in the low rpm - the Yosh gives the stock power a boots across the board without changing the stock bike’s power personality. That is, you’re still looking at a machine that does its best work in the midrange, but now there’s more boost. Yorks said the pipe didn’t help the bike rev further up on top but appreciated the across-the-board boost of what he estimated at a five to ten percent.

RM-Z250 stock

RM-Z250 stock

Dirt Rider's Long Haul 2016 RM-Z250 gets some Yosh goodiesPhoto by Pete Peterson

This bike is my Long Haul, and what I really want out of the engine is a faster rev rate. This pipe was a power improvement for me, and I agree with Yorks that a five or ten percent boots is a good description of the overall increase at any rpm, but the exhaust didn’t affect the rev rate as much as I’d wanted. It was a tiny step forward and I have some other plans for this bike, my Long Haul, to see if I can get it more in-tune with how I like an engine to run.

Maybe the best thing about the pipe is the sound – the bike gets a barkier and snappier note and never gets too loud. It’s great when a pipe can improve the tone without boosting the volume to bad levels. The bike also fired to life a little more eagerly with the new exhaust.