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Only $10 for all 2026 SX, MX, and SMX series.
I'll be interested to hear your feedback testing this PC pipe back to back with the Bill's pipe.
I've ridden the PC Champ Stamp pipe on my buddy's 2026 YZ250 back to back with my 2019 YZ250 with a Bill's pipe / PC silencer.
The confounding factor on our bikes is the difference in reed valves... He has the Boyesen and I have the VF3 system.
We have both cut the heads down on these bikes, run race fuel and dialed in the jetting.
I felt like my bike with the Bill's pipe starts building more torque earlier in the RPM range.
I think his setup with the PC pulls longer on top.
We haven't switched bikes at a fast / wide-open track yet... (My little track doesn't have space to wring out a 250 two stroke).
The Bill's pipe has been my favorite for a long time on the YZ250, but this new PC pipe is great.
3 motos into my day... The champ pipe has slightly less bottom than the Bill's and a little longer pull on top.
It's a good pipe, but I could go either way between it and the Bills.
From memory, the FMF has a lot more bottom than both and much less top.
The regular PC had zero bottom and a massive top end and I have no desire to ever try that one again. It was just too hard to ride for my feeble skills, but I'm sure it rewards a guy who revs and rings it out everywhere like a 125.
Anyway, the champ pipe will stay on for the time being!
Nice and broken in. Blue and its first dent...🤣
No PC RX350 pipe talk?
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I just switched my pilot to a 48 and my main to a 175 felt like I lost some midrange and top end with the 175. It felt like it started to go flat right before it switched to the main jet and didn’t want to rev out as much as before. What clip position do you have on your jet needle? My bike is stock besides a Pro Circuit silencer non shorty version.
Go with a 40 power jet (one size leaner than stock 50) and move the needle to the 3rd position, which is richer than stock n3ew-2. It takes the flat spot out of the mid range.
You still might prefer the 178 after this change, and it's also depndent on temp/altitude, but give it a shot.
Clip is stock position, I have a full pc motor though so I’m sure that changes things vs a stocker
So 48/3rd/175/40 Power jet? The 40 power jet confuses me being leaner but I guess it’s because the clip position is richer?
Doesn’t look like the PC Champs pipe gives up any bottom compared to the stocker with the PC motor. I’m curious what it would perform like on a stock motor. When I switched to the 48/175 my bike felt like it picked up the front wheel easier and more predictable in 1st and 2nd, but barely wanted to leave the ground in 3rd gear compared to before with the stock 50/178. My only guess is the 178 leaned the midrange out to the point it didn’t have the grunt to pick the front wheel up in 3rd like before. The only reason I swapped to the 48/175 is heard so much about the yz250 coming rich stock. I guess most people tend to run 40:1 instead of 32:1 so they’re on the richer side.
Exactly. It'll balance everything out from bottom to top, or at the very least put you in the ballpark better than the typical jetting approach you see out there.
Getting the needle into the 3rd position is key and really only works well by leaning out the power jet 1 size. If you are riding at a bit of altitude (3-5k) and warm weather, you'd go N3CW-3...1 size leaner but you still keep it in 3rd position. Equates to "half" a clip compared to N3EW-3 iirc.
If the top still feels flat/lean after that, try the 178.
Edit: Also, none of this matters if your float is off... You usually never have to touch it, but double check.
The power jet is blocked by the slide below 1/2 throttle, you can see this if you look into the back of the carburetor where the little brass spray nozzle hangs out into the bore.
The CDI unit closes the power jet solenoid at 8500rpm and above according to the Yamaha book.
When you lean out the power jet from 50 (stock) down to the 40, you reduce fueling from around 1/2 throttle to full throttle up until 8500 engine rpm.
changing from clip position 2 (stock) to clip position 3 gives you back some fuel from just above 1/4 throttle to about 3/4 throttle at all engine rpm.
It's a subtle change that affects some riders, depending on which portion of the throttle range they use in certain RPM window.
That really depends on the rider, track, etc.
Most of us are rarely at full throttle, even when we THINK we are.
A 65 year old buddy of mine says "Did you actually feel the throttle stop and pull the cable tight?" whenever discussing starts...
He's a great starter.
I’m about 200 feet above sea level 70-85 degrees. The 48 pilot wouldn’t be the cause of the front wheel not picking up as easy? So the 3rd clip position will richen 1/4-3/4 and the 40 power jet will lean 1/2-WOT to balance it?
The pilot doesn't matter past 1/8 throttle iirc. cwtoyota probably remembers more about it than I do. My jetting has been dialed in so long that the details have somewhat gotten fuzzy to me.
At seal level to 4k I'd leave the pilot at a 48 though and adjust air screw accordingly.
My air screw is currently one turn out. So without having the clip on the 3rd position to richen the needle jet would that lead me to feeling like the 175 was too lean, and not being able to feel the real improvements going from the 178 to 175?
In my opinion, 175 is too lean on pump fuel... At least here on the west coast at sea level.
I haven't run pump fuel in a lot of years, but I'd venture the guess that @SoCalMX70 is right about running the 48.
I run 45 pilot / 175 main on a 50/50 fuel mix using Trick 110 leaded and 92 ethanol free pump.
You really have to do the testing to know for sure... Have a clean air filter when you test.
Work your way up through the circuits and stay within the throttle range where they operate when you test.
Start with the pilot, then do the needle, then the main jet.
Power jet changes require you to re-test your needle, then main jet.
It's a lot of parts swapping, but once it's dialed, it's a great thing.
lol all the hate of EFI two strokes make me laugh when reading all this. My 2025 tc 300 ran so crisp all the time. This yz def barks but I’m $1k into this motor just to feel as good as a stock ktm 300 efi bike.
Do you run 32:1 or 40:1 seems like most people that like the 45/3rd/175/40 seem to be running 40:1. I’m running 32:1 because I like to rev the piss out of my two strokes as I feel a two stroke should be ridden. I’m thinking 48/3rd/178/40 might be my best bet with 93 pump gas 32:1 if this 48/2nd/178/50 and if all else fails then back to the stock jetting it is 😂
My bike ran good with stock jetting at 32:1 honestly just tinkering to see if I can get any improvements from jetting alone.
Pit Row
All my bikes share the same mix at 32:1 with Yamalube 2R and 50/50 110L/pump.
I did not say I was running the #40 power jet. I explained what it does.
I am running a different needle (2002 part) and the 45/175.
I also have a VF-3 reed system and I re-cut the head to my own spec.
I meant to touch a bit more on the 40PJ last night. I think it works well for me because I almost never twist the throttle all the way to the stop. Really, just on starts. The 40PJ/needle in 3rd position is just so dialed for the way I ride.
My setup at GH with the Champ pipe was epic, honestly.
Edit: other mods...
VHM head with "MX" dome
VF3 Reeds
I am a lower part throttle guy fairly often, even at mid/high RPM.
I think my part throttle time is often around 1/4 to 1/2 throttle and when I need more I twist it straight to the stop.
Guys who use 1/2 to 3/4 throttle a lot of the time in mid RPM are using that power jet quite a bit. It sounds like you might be in that range.
I want to give this a try. Looked on Amazon. Would you mind sharing the link to the wipes you purchased?
why arent there more exhaust stages like with exhaust manifolds on cars. a pipe tuned for a relatively stock bike shouldn't work on a radical engine package and vice versa. it's not necessarily the pipes fault if you dont like the pipe
im actually sort of surprised that PC only offers one pipe off the shelf with no recommendations for best supporting mods. anybody know what the gains are for a RV-style engine package with a matched pipe vs ots?
Don’t give them ideas. You’ll have them pricing two stroke pipes like they have the four stroke pipes lol.
Switched back to the 178 still have the 48 in, and the bike feels a lot better. I’m debating on trying the 48/3rd/175 or 178/40 setup or just leaving it alone.
https://www.youtube.com/live/ZTIU3Lij7TM?t=7593&si=xOiS604iG8wRERfx
Here is Mitch talking about this pipe. My man is the biggest two stroke legend ever.
Doing a little bit of math, we have the maximum torque of the champ stamp at 31.7 ft-lb. It appears to match the 7750 rpm range right (it says 7700 on the chart)? Applying the formula of POWER (HP) = TORQUE ( FT-LB )*RPM/5252 it is around 46.8 HP, which makes sense if they were dynoing a stock YZ 250 (you can see the stock bike around 44 HP max, which is what they usually dyno). So that means the champ pipe peaks at around a whooping 49 HP, close to that 7 HP RV was talking about (a lot of things might come into play). If this was indeed a stock YZ 250 in the 3 dyno runs, then this pipe might be the best bang for your buck ever.
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