Putting in a new top end

ZR2

Member
Joined
Jun 24, 2003
Messages
38
Likes
0
#1
Hi, Please don't laugh at me for not knowing how to do this but how do I put in a new top end and what parts do I need. I have a 2002 Honda CR125 and its probably one of the cleanest bikes out there and gets ridden alot. I clean air filter and change transmission oil every time I ride, oil change regularly. I really don't know much about the technical stuff, just the basics and would really like to know about putting a new top end in on my bike.

If someone could please explain what I ask for when I go to order a new top end, parts, and how to do it. Thank you.
 

Danman

Lifetime Sponsor
Joined
Nov 7, 2000
Messages
2,211
Likes
2
#2
Not much of a 2-stroke guy, but I would not attemp it without a manual. You will more than likely need to order a top end kit. It will have a piston, rings, and wrist pin. I would suggest you go to the liberary check out Eric Gorr's book. I forget the name of it, but it contains lots of the basics your looking for. A manual specific to your model would also contain things your looking for as well as torque specs for all the bolts.
 
Joined
Jul 22, 2002
Messages
853
Likes
0
#3
...and it just so happens I have an extra service manual that needs to find a home Motoman9873@excel.net

you'll need a new wiseco piston(includes ring, c clips, and wrist pin), new oem wrist pin bearing and a new top end gasket set. I always have my cylinder professionally honed...and re-plated every other time.
 

rickyd

Hot Sauce
Joined
Oct 28, 2001
Messages
3,447
Likes
0
#4
I definately reccomend getting a manual.. It will come in handy in the future also..
Rick
 

ZR2

Member
Joined
Jun 24, 2003
Messages
38
Likes
0
#5
Thanks for all the replies. I emailed you about that serivce manual. Thanks.
 
Joined
Jun 3, 2003
Messages
74
Likes
0
#7
I've never done a top-end either, but I've done enough homework to know how to. I've found out it's really pretty easy. No way am I gonna send it to a shop.

Good little link
http://www.dirtbike.com/forums/topic.asp?TOPIC_ID=9949 (for a '03 CR125)
http://www.dirtbike.com/forums/topic.asp?TOPIC_ID=10635 (for a '00 CR125 w/ pictures)