[jkill351]

i have an 05 crf50f with a +2 sdg swingarm and matching forks. ive installed a fmf powercore4 and a bbr revbox. i want to replace the motor with a new one and ive picked the 125cc gpx/pitsterpro with oil cooler. does anyone have any experience with this motor? i also noticed that the 140cc gpx is the same price. will it produce a lot more power or will it be an overkill on the 50? also does anyone know the power output in comparison to a yzf125 or a crf150f6? im familiar with these motors. my kids are between 50-100lbs which would you recomend for this size rider? they are very experienced and are excited about getting more power and of course they want the 140. any and all suggestions are apreciated thank you

 

[taz69]

Go with the 140.. I run a 184cc (punched out 160) In my CRF50 and love it.. the 140 should make around 12 to 13hp with a 26 or 28mm carb on it and make a good bit of torque.. A CRF150F makes 12HP on a good day.. Not sure about a YZF125????

 

[zwieblekopf]

If they are good riders they should have no problem with the 140, my brother runs a gpx125 bored out to a 146. It's a good amount of power, but not anything that an experienced rider can't handle

 

[sr20hardbody]

i'd go with a 140 they have the big valve head and firepower354 can bore the cylinder for a high compression 57mm piston when the times right.



why the gpx though? why not go for the reliable piranha yx140

 

[zwieblekopf]

why the gpx though? why not go for the reliable piranha yx140

same motor, different badges

 

[jkill351]

that sort of feed back is exactly what i was looking for. why the pirhana? i thought when i was looking at the pirhana that it was made by gpx or pitsterpro. but thats what im asking is what would you buy for your kids?

 

[doopsx3]

.......what would you buy for your kids?



bored and stroked HONDA

 

[taz69]

IM not sure what the difference is in a GPX140 or a Piranaha 140.. I think there the same engine sold under two different names???

 

[jkill351]

so i bought the pp 125 from pitsterpro. when i asked the salesman what the biggest diffrence between the 125 and the 140 is the 125 has a shorter gear ratio. supposidly the power output between the two is very close with the biggest diff being gears. im not all about my kids going super fast but being able to scream around corners and getting that front wheel off the ground. we mostly trail ride so the need for long gears is nonexistant.

as far as the honda motor is concerned im going to put it im my daughters quad. it came with a 110 but its junk. ive had to change all sorts of stuff on it. but this way when she gets bigger i will be able to put the honda motor back in the honda for her when its time. in oregon kids have to be at least 8 to ride a dirtbike and shes only 6. i thought about boring and stroking the 50 but getting the 125 is the cheapest and easiest solution, especially sence i have plans for the 50 down the road.

thank you for all the responces. i really do apreciate the help. and to the guy from t-bolt. im sorry i needed the oil cooler and it came with it from pp, however i am going to purchase the rest of what i need from you guys. i strongly feel the need to spread my money around between diffrent online companys with the majority going to my local shops.



a dollar spent outside of your local community may never come back. so when a person sends all of thier money abroad how can they realistically expect to ever make more when they just enrich other locals (i dont care weather its china, japan, germany, england, or even canada)

 

[minimotos95]

yzf125

with what color powerband?





PP is always a good choice unless you are a die hard honduh lover