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Pro Circuit High Compression Piston
Pro Circuit High Compression Piston

$279.99 - $379.99

Item #PRC001G

Read More
19 Reviews
4.5 out of 5 stars
5 Star   13 4 Star   4 3 Star   1 2 Star   0 1 Star   1
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All Reviews
Wyoming
Durability 5/5 Ease of Installation 5/5 Performance 5/5 Power 5/5 Style 5/5
Try it!!!!!

I added this piston kit to my CRF450X and it made vast improvements to the torque and handling. I'm an unsponsored XC racer and I'm able to throw the front tire around, run a taller gear and use the extra grunt all the time. I've ran it for one season and had zero problems. I'm adding this to the rest of the garage. Love the product. This bike is a blast to ride. Nice work.

Top 1000 Verified Purchaser
Florida
Durability 5/5 Ease of Installation 5/5 Performance 5/5 Power 5/5 Style 4/5
Great upgrade

Good piston kit. I like the fact that it came with a coated piston pin. I would have given it five star rating except I think it's over priced.

Verified Purchaser
Ease of Installation 5/5 Performance 5/5 Power 5/5 Style 5/5

Improved power delivery though out the whole engine range. Most noticable at mid high range. Great mod product if your looking to keep your bike mildly stock without busting your race budget. No additional engine mods needed to the engine. Im sure after 20 hours I will be rebuilding the head with a new piston because the extra pressure on the valve train will stress the stock valve springs to there max. Get an hour meter with it. Im sure 20 hours is the max if your racing the bike.

Verified Purchaser
Ease of Installation 1/5 Performance 4/5 Power 4/5 Style 3/5
Pro Circuit Piston set.

JD piston, and pin, with OEM Kawasaki rings, packaged as Pro Circuit piston kit! Not what I expected.

I am for UAE
Durability 5/5 Ease of Installation 5/5 Performance 5/5 Power 5/5 Style 5/5

It give the bike high performance and acceleration to the bike

Johnstown, pa
Durability 5/5 Ease of Installation 4/5 Performance 5/5 Power 5/5 Style 5/5
Good equality

It was easy to install and once u run it my 08 rmz250 had a little more power than it did before and it changes te sound of ur bike to while if u ask me my bike sounds alot better now

Hermiston, OR
Durability 4/5 Ease of Installation 5/5 Performance 5/5 Power 5/5 Style 5/5
08 RMZ 450

I installed this kit in my 08 RMZ450 along with new Faction MX intake valves. The bike has more power all through the range, starts easier and I can ride the bike a gear taller in all situations.
Great product that I would highly recommend.

Massillon, OH
Durability 1/5 Ease of Installation 1/5 Performance 1/5 Power 1/5 Style 1/5
DONT BUY

Don't buy this! I bought this for my 2010 yz250f and I got the JE piston and the stock rings for it. The stock rings do not fit this piston. The JE piston is a two ring set up and the stock piston is a 3 ring set up so you cannot use the stock rings for it.

Cairo, NE
Durability 5/5 Ease of Installation 5/5 Performance 5/5 Power 5/5 Style 5/5
GREAT PART

I put this piston in my old crf 450 (05) and noticed a good improvement over the stock piston. a day after i put it in though, i threw a keeper out of my right exhaust valve - my fault the valves were shot.
installed kibblewhite valves and springs. torque was incredible- almost tractor-like. with an exhaust as the only other motor mod, it was good enough to win me a trophy at the sand drags- 5 bike lengths on a cr500. definately worth the money and cheaper than a full exhaust system.

Ease of Installation 5/5 Performance 3/5 Power 3/5 Style 5/5
Simple

After installing this piston and riding one day, I couldnt feel much of a difference. It may be from me rejetting my bike incorrectly at the same time however. piston looks great and easy to install. just make sure you dont drop any piece into the crank case or lose any pieces.

See 9 More Reviews
13 Questions
Answered:   13
Not Yet:   0
kyle
Q: Does this package come with the coated wrist pin?
Over 3 years ago
MotoSportExpert
Top 1 Contributor
Over 3 years ago
A: No. Just a standard wrist pin.
shaneo173
Q: How much low to mid hp would u gain in conjuction to a single side fmf factory 4.1 w/ mega bomb and stage 2 camshaft from hot cams? straight 93
Over 3 years ago
2014 crf250r torque and peak horsepower would be nice to
MotoSportExpert
Top 1 Contributor
Over 3 years ago
A: The internal combustion engine is very simply put a basic air pump. The more air/fuel you and intake and exhaust from the motor, the more power you will make. HP gains are very subjective to gauge on any one or combination of performance parts. Things like the age of the motor, the tune of the air fuel ratio, the altitude, etc will all have an effect on PEAK HP numbers. Many performance products will not increase your PEAK HP, but rather move the HP to a different RPM range than the stock motor.
Enduro8expert
Q: What is the compression ratio on crf150r?
Over 3 years ago
I have had this piston for a while and it is amazing but I have always wondered what the compression ratio is.
MotoSportExpert
Top 1 Contributor
Over 3 years ago
A: Pro Circuit list the compression as +1 point and still able to use premium pump gas. They do NOT release the exact compression ratio on their pistons.
JD22
Q: Can i use this product?
Over 4 years ago
can i use this high compression piston along with both my intake and exhaust hot cams? and will i still notice a difference in power an performance? i have a 2006 yz250f
MotoSportExpert
Top 1 Contributor
Over 4 years ago
A: A Pro Circuit High compression piston will give you more bottom end power. It will work with other modifications such as the Hot cams, porting and exhaust. You will have to rejet the 2006 Yamaha YZ250F bike for the modifcations and we have products to help you with that.
mxrider65
Q: What compression ratio does it bring a 2002 honda crf450r?
Over 4 years ago
I have a 2002 Honda crf450r and right now I have a 13:1 high comp piston in it and I was wondering what the compression ratio was on this piston.
MotoSportRyanT
Expert MotoSport Staff
Over 4 years ago
A: This Pro Circuit Piston would be the same 13:1 compression ratio as the high compression piston you are running now.
aichokeu
Q: If I am Installing a high comp piston for the first time, do I need the gaskets too?
Over 5 years ago
Also, can you run lower octane gas with this piston?
MotosportStaff
MotoSport Staff
Over 5 years ago
A: Yes, you will definitely need a new gasket kit if installing this piston. Also, depending on how many hours are on the engine it would be a good idea to replace the bottom end at the same time. The higher compression piston is harder on the crankshaft than the stock OEM setup. You will want to run higher octane fuel than required for the stock compression for the bike to run properly without damage. Mixing premium pump gas 50/50 with race fuel is a safe medium.
JohnnyD
Top 1000
Q: Your specs on this product specifically call-out pump gas not race gas. What is the correct answer?
Over 8 years ago
91 octane is the highest available pump gas in SoCal
Drewski
MotoSport Staff
Over 8 years ago
A: The description is saying that you can use either premium pump fuel or race fuel. Obviously you will get more of a boost out of race fuel, but
premium pump gas (91-93 octane) will be fine
rider313
Over 8 years ago
A: this piston is designed to run off 91 octane gas. so you will be fine.
moto75
Top 50 Contributor
Over 8 years ago
A: the lowest i run is 93 in the summer and 103 in the winter, itll bog without that set up. you can always use 91 with octane boost
amr126
Q: Is this simply a JE piston?
Over 8 years ago
To what I understand JE pistons makes the pistons for pro circuit. They offer 12.8:1 and 13.5:1 compression for the YZ 450F, so which one is it? (don't say 13:1)
keify
Over 8 years ago
A: we use the 13:5 cr on our yz 450s more bottem bark and no loss of upper end. most 250fs come stock now with high\er c.r. most 450s do also
keepitpinned529
Q: What is the compression ratio on these pistons?
Over 8 years ago
WnyRacing
Top 1000 Contributor
Over 8 years ago
A: 13:1 is the compression ratio.
laptop
Q: Are the gaskets included or just the piston kit
Over 9 years ago
moto75
Top 50 Contributor
Over 9 years ago
A: just piston kit
JesseC
MotoSport Staff
Over 9 years ago
A: we do sell a combo with the gaskets but this exact one is just the piston kit.
1 - 10 of 13
Fitment
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See Fitments
# Part Numbers
Product Variant Manufacturer Part #
Pro Circuit High Compression Piston RPH14250F1
Pro Circuit High Compression Piston RPH16250F-1
Pro Circuit High Compression Piston RPK16250F
Pro Circuit High Compression Piston RPK17250F-1
Pro Circuit High Compression Piston RPK18450F
Pro Circuit High Compression Piston RPS14250F
Pro Circuit High Compression Piston RPS18450F
Pro Circuit High Compression Piston RPH08150R
Pro Circuit High Compression Piston RPH08250F
Pro Circuit High Compression Piston RPH09250F
Pro Circuit High Compression Piston RPH04250F
Pro Circuit High Compression Piston RPH08450F
Pro Circuit High Compression Piston RPH09450F
Pro Circuit High Compression Piston N/A
Pro Circuit High Compression Piston RPK09250F
Pro Circuit High Compression Piston RPK10250F
Pro Circuit High Compression Piston RPK09450F
Pro Circuit High Compression Piston RPK10450F
Pro Circuit High Compression Piston N/A
Pro Circuit High Compression Piston RPS08250
Pro Circuit High Compression Piston RPS05450
Pro Circuit High Compression Piston RPS08450
Pro Circuit High Compression Piston RPY08250F
Pro Circuit High Compression Piston RPY10250F
Pro Circuit High Compression Piston RPY08450F
Pro Circuit High Compression Piston RPKTM14450
Pro Circuit High Compression Piston RPY14250F
Pro Circuit High Compression Piston RPY10450F
Pro Circuit High Compression Piston RPY16450F
Pro Circuit High Compression Piston RPK16250F-1
Pro Circuit High Compression Piston RPS14450F