Raptor 125 engine mods

[fast shee]

So I am in the process of getting a raptor 125. I have been looking around for some engine mods to do on it but coming up short aside from exhaust. I am debating on building a raptor 125 for xc or buying a raptor 250 roller and stuffing a Honda crf150r mill in it. Any of you racing these and have any go fast info I can use for my decision. My sons class will allow up to 150cc. Thanks

[T@AFP]

We have been involved with GNCC racing on our 125. The motor is less to be desired. Even with several motor mods, it's still a turd....
One of our friends put the BBR 150 kit on his. It seemed to be a little better. But, then you have the over heating problem. Which is already a concern with the 125.
My opinion is to continue withe the 125 and do some mods. I would suggest when purchasing hi compression piston. Make sure you get the ones that use the stock Yamaha rings.

Tom

[fast shee]

That's what I was thinking. I might just find a roller and put the 150r engine in it and be done with it. A friend of mine has a raptor 125 with the 150 kit and its not very impressive. Wasn't sure it was something he was missing or just improper setup.

[ccdhowell]

Look up jwiedner on the board and send him a PM. He did my engine just over a year ago and it's still running pretty strong. He has 12:1 pistons and a special cam grind that web cams does for him. I didn't want and all out build, but he can get over 20 horses on a 150 build and it will be reliable. He's swamped right now, but is a great guy and I'm sure he would talk to you. PM if you want his phone number.

Chris

[jweidner]

Hi Fast Shee,

In my opinion, if your class will allow you to run a crf150r in a Raptor chassis, that is what I would do.

As far as the Raptor 125, these quads run very well for only being out a couple of years. If your class will allow you to go to 150CC, the 150 big bore kit would not be my first choice. The piston is very heavy and you will run into high cylinder temp, not to mention the rotating assembly has not been balanced for that weight piston. You do have other options though!!

When increasing CC's all other engine components must be well thought out. Engine combination is the key to HP. If one thing gets missed your combination will not run well nor will it be efficient!

Give me a call if you would like to discuss options,
Thank you,
Precision MotorWorx
Jason Weidner, 484-369-1608

[exhausted]

What options are there when staying under 125cc? will a piston, cam and carb wake it up much? we just have an fmf slip on right now, and it's pretty slow.

[exhausted]

Jason, I called and left a message last week and haven't heard back from you. Any info on how much a carb and intake help with a full exhaust?

[jweidner]

Hello,

Sorry if I have missed your call, parst 2 months have been very busy. please give me a call.

Thanks,
Jason 484-369-1608

[exhausted]

Originally posted by jweidner
Hello,

Sorry if I have missed your call, parst 2 months have been very busy. please give me a call.

Thanks,
Jason 484-369-1608 you called me back after I called a second time, but I still haven't recieved the email you said you were gonna send of some options and prices.
my email is slctk@verizon.net

[jlhughes750]

our 125 raptor holeshoted cobras and trx 125 kits at the last local it runs very well and is still 125.
the right combo of parts hit great #'s on the dyno. RAGE in texas built ours. I will not brag about dyno #'s...I dont wanna start that battle. But, there are a few little secrets to putting out good power, not to mention these are great starter quads for racing the bigger bikes. good luck.

[exhausted]

That would be awesome. I'd like some insight into your mods as I'm having a hard time getting anyone to help me.

[billyr85]

Hi there, we are down in Australia and just had our daughters 125 done up with some work. They are a painful engine to get right. We bought the stage 3 kit from HMF which was, piston,cam,keihin PE28 carb and full exhaust and free flow air filter.

The shop put on the bits on it and ported head to suit and dyno'd it with the pe28 carb and they said was a 2 stroke carb so ended up putting the stock mikuni back on.

end results was 10.6hp with lid off and 10.0hp with lid on and smaller main. but the A/F ratio is all over the shop, not running lean which good but rich in spots.

Has anyone else had trouble getting the PE28 carb to work on the bike

[jweidner]

Hi Billyr85,

What needle are u using, main jet and pilot jet. New or old style PE 28MM carb.. PWK 28mm are 2 stroke. PE is 4 stroke. Both carbs are not built the same due to fuel pulse through the venture.