Confusion on 07 YZ125 rebuilding parts (rings, pistons)

[Stusmoke]

Hey guys as some of you already know I'm rather uneducated in this area and just need a clarification.
I've been told the rule of thumb for the 125s is 1 piston for every 2 rings. That said, if I follow the pattern of buying   http://www.motocrossparts.co.nz/motoxspares.php?category=92&brand=105&page=1&piece=1298   For when I just need to do the rings and   http://www.motocrossparts.co.nz/motoxspares.php?category=92&brand=100&page=1&piece=1054   On the next rebuild when I need to do both the piston and rings Will this work out? These are all the parts that I need for doing the rings then piston and rings and so forth?

Thanks guys and sorry for being a tard xD

[MetalMike1982]

Im sure that would be fine . Unless your an A rider out there to be a star and run quality 2t oil you should get good life out of your topends . A compression tester is an easy way to tell whats going on inside your motor

[Stusmoke]

Yeah I haven't actually purchased the bike yet but my CRF250R crank bearings died, then got dragged up into the cylinder... basically everything that can be damaged in an engine is completely arsed Dx so yeah $3000 to fix that or our dealer give us $500 for the bike as is thats taking off the $280 we already owe him in labor. So I'm planning on taking the $500 and going to look at some 125s xD When I do get the new bike I'll definently be picking up some tools. List of tools I'm gonna need for a rebuild is below:

piston ring tool
Full socket set
Full closed end spanner set
Compression tester
Needle nose pliers
feeler gauge
digital vernier caliper
Loctite
gasket scraper

Again I am sorry for being so retarded Dx

Thanks guys and if im missing anything pelase do say
Thanks again

[eprovenzano]

Keira2142 maintaining a two stoke does not require more than basic tools.

As far as you list goes:
piston ring tool - I use a small screwdriver
Full socket set - a standard set will be fine
Full closed end spanner set - again a standard set will be fine
Compression tester
Needle nose pliers
feeler gauge
digital vernier caliper
Loctite - blue
gasket scraper - I use a paint scraper, or anything I can get my hands on..

One thing I would add, (I need to get one too) is a torque wrench

Keira2142 please remember the only dumb question is the one you don't ask. We've all been in your shoes. We all had to start somewhere...   Please feel free to ask, we are all here to help.  You may get different opinions, (that's what makes this board interesting) but we are to help.

Rebuilding the top end on a 2 stroke is not difficult.  If you take your time, and take pictures as a reference it really is something any garage monkey (like me) can handle...

[Stusmoke]

eprovenzano thanks for great advice! Well actually thank you everyone who posted for the great advice. So a torque wrench aswell.... alright sweet. My main reason for the concern regarding if I do 1 piston for every 2 rings is http://www.motocrossparts.co.nz/motoxspares.php?category=92&brand=105&page=1&piece=1298  is only one ring and the full piston kit  http://www.motocrossparts.co.nz/motoxspares.php?category=92&brand=100&page=1&piece=1054   has many rings to it. I said full sets cos thats what I have... Sorry that was silly of me. Im also just wondering if the 2006 model YZ 125 has much mechanical difference between the 07 125. I would like to get a full repair manual for it just to be on the safe side but I can't find one for the 07. Of course I can find one for the 06 though

But so long as buying http://www.motocrossparts.co.nz/motoxspares.php?category=92&brand=105&page=1&piece=1298 for the first time round and http://www.motocrossparts.co.nz/motoxspares.php?category=92&brand=100&page=1&piece=1054 for the second has EVERYTHING I need Im happy.
Thanks for your help guys

[eprovenzano]

One piece of advice.  I would not order any parts until you are ready to do your 1st top end.  At that point, I'd do both piston, ring(s) and the wrist pin needle bearing.  Pick a brand, OEM, Wiseco, etc., and stick with it.  I don't believe you can use rings from different brands.  Example you cannot use an OEM ring on a Wiseco piston.  After that I'd follow the process you posted.  As for when it time... that is where the compression tester in invaluable.  After you do a complete top end, use the compression tester to set a base line.  From time to time, recheck the compression against the baseline.  When it starts to decline too much, its time to freshen up the top end.

My son used to ride a 99 YZ125.  We purchased it with a fresh top end.  He rode it for 2 years, (trail riding mostly), I sold to  a friend of mine.  He has ridden it for 3 years...  In all that time its still running the piston and rings that was put when I bought it.  I have told my buddy, that I am going to steal the bike and tear it down and force him to redo the top end...  It been due for quite a while but she just keep on running.  These bikes really can take a lot of abuse. With some basic maintenance they just keep running.

[MyckMcClung]

most of those tools, like the ring tool is silly and not needed, I use my finger nails.......

[TMKIWI]

most of those tools, like the ring tool is silly and not needed,

Is there such a thing.

Keira I take it you are NZ, Where abouts ?

[Stusmoke]

Wow you posted that while I was reading xD. Nah I'm in Australia. I don't ride motocross despite how much I would love to I just can't afford it.
I don't have finger nails haha. Okay so don't order the parts until I need them and don't mix and match.. got it! Thanks guys! Also I should note that I'm not a huge perfectionist I don't need my compression to be at it's very top best everytime. I can understand that would be invaluable to racers but not to me so thats where I can save a couple of $.
Thanks again guys anymore advice is welcome!

[dbf498]

One other thing not on the list is a repair manual, i.e. Chilton's or Clymers. These books have all the instructions you'll ever need to not only do a top end rebuild but will also have general maintenance guidelines. It will also give you the torque specs you'll need when you get ready to do the top end. I personally believe this is one of the best "hand tools" you can invest in.

[Stusmoke]

Im also just wondering if the 2006 model YZ 125 has much mechanical difference between the 07 125. I would like to get a full repair manual for it just to be on the safe side but I can't find one for the 07. Of course I can find one for the 06 though

Sorry I didn't really make it clear in my first post. But I am intending on buying a full repair manual for whatever machine I happen to get. Thanks though

[ruskee]

Im pretty sure 06 to like 08 or 09 everything is the same

[Stusmoke]

Righto thanks for that Ruskee. Appreciate it. I figured it would be since no skinny ever put much effort into the screamers after about 2005.

Thanks