Posts
459
Joined
9/23/2014
Location
Katy, TX
US
WileCyot
4/26/2016 6:22pm
4/26/2016 6:22pm
Edited Date/Time
4/28/2016 9:18am
Guys,
Picked up an 03 KX125 to rebuild and I'm not very familiar with these engines. I understand engines in general so I'll be fine with that but the queston I have is in regards to the Athena Cylinder and Head combo.
The bike currently has a damaged Athena Cylinder. I'm looking to send it off and have it replated. Would it be worthwile to have it ported while it's gone or even opened up to a 144? I prefer to leave it stock bore but it's worth having the knowledge.
Also, the piston that came out was an Athena. Looks like the piston melted and the ring snagged a port and drug itself up and down the cylinder. The piston is a flat top and it's my understanding that the OEM is a domed unit. Should I purchase a domed piston or go with a flat top? I'm a wiseco forged nutswinger as I've had great luck with them in my CR500 and an old KX250 I built so I was planning on ordering an 822M05400 which is specific to 2003 but noticed there are 2 other options. 788M05400 which is 03-08, a Racers Choice, ElectraCoated, No Intake Window, & Pinned on Centerline. There is also 755M05400 which is for years 1995-2008. It's a Flat Top Conversion, No Intake Window, and Pinned on Centerline.
What do I do?
Picked up an 03 KX125 to rebuild and I'm not very familiar with these engines. I understand engines in general so I'll be fine with that but the queston I have is in regards to the Athena Cylinder and Head combo.
The bike currently has a damaged Athena Cylinder. I'm looking to send it off and have it replated. Would it be worthwile to have it ported while it's gone or even opened up to a 144? I prefer to leave it stock bore but it's worth having the knowledge.
Also, the piston that came out was an Athena. Looks like the piston melted and the ring snagged a port and drug itself up and down the cylinder. The piston is a flat top and it's my understanding that the OEM is a domed unit. Should I purchase a domed piston or go with a flat top? I'm a wiseco forged nutswinger as I've had great luck with them in my CR500 and an old KX250 I built so I was planning on ordering an 822M05400 which is specific to 2003 but noticed there are 2 other options. 788M05400 which is 03-08, a Racers Choice, ElectraCoated, No Intake Window, & Pinned on Centerline. There is also 755M05400 which is for years 1995-2008. It's a Flat Top Conversion, No Intake Window, and Pinned on Centerline.
What do I do?
If you want to go to 144 then you will need a full porting job with the port heights reset after it is over bored. I can't remember if the Athena's have a 2 piece head or not so modifying the head to accept the 58mm piston may present a problem. My reccolection is that the Athena parts are not interchangeable with OEM.
The Shop
Is the exhaust port that is damaged on the Athena?
http://www.mt-llc.com/serviceInfo.php?id=19
We can also service your Athena cylinder as well:
http://www.mt-llc.com/serviceInfo.php?id=7
- Send me an email at chip@mt-llc.com with the details of which Athena kit you have, which piston you are currently using and I will get you some information. If the Athena piston is no longer available, I am sure we can find a suitable replacement, but we will need some specific measurements.
If there is anything I can do to help, let me know.
Post a reply to: 03 KX125 Rebuild.... Athena Cylinder & Head Questions.....