Engine Overhaul

[vicky_boy]

I am planning a complete engine overhaul of my CG125 2010 as i plan to keep it for sometime. Here are the parts which i am going to be replacing. All parts are going to be of genuine atlas Honda

1) Piston
2) Piston Rings
3) Valves (Input + Exhaust)
4) Both valves Stem seals
5) All 4 outer and inner valve springs of both valves
6) Pushrods
7) Cylinder Barrel
8) Cylinder Head gasket
9) Cylinder Base gasket
And any washels or small nut bolts miscellaneous which might need replacement upon opening

Now reason for replacing barrel is that i want size 0 piston installed and the current barrel would need boring and size 50 piston would fit in it.

Any one having experience of engine overhauled or might have some experience regarding this and total expenditure idea. Plz do share.
Also any tips or any part which i am missing plz do let me know.

Note:i have been quoted 8k incl labour is it reasonable

[talhabinomar]

One thing which i came to know after much hassle that go for the bigger size piston rather than the sleeve type thing because for sleeve they will tool your original sleeve and then the sleeve installed doesn't have the material which was installed first, so better to go for a slightly bigger piston.

[vicky_boy]

One thing which i came to know after much hassle that go for the bigger size piston rather than the sleeve type thing because for sleeve they will tool your original sleeve and then the sleeve installed doesn't have the material which was installed first, so better to go for a slightly bigger piston.

I didn't understand you brother...........the mechanic said that if you replace the cylinder size 0 piston would fit

So i thought he meant replacing this barrel altogether. I dont understand how else cylinder would be changed

[vicky_boy]

..........

[abobobilly]

@vicky_boy!

Okay, what you have stated, is not called "Complate" engine Overhaul. Its just Head, Cylinder, Piston and Piston Rings replacement. But yes, you will have to change everything including:
- Piston & Piston Rings
- New Gaskets for everything
- Valves & Valve Seals
- Push Rods
etc

If its the first time your bike is getting opened, then:
- Stock sized piston will work
- No bore will be required (You will have to ask them specifically NOT to bore it, unless absolutely necessary)
- you don't need to change the Cylinder Block, Valve Springs or Rocker etc.

This is coming from my experience while getting Piston Rings change on my CG125. I opted not to change the Piston, thinking its fine and it'll work. Result, it needs work once again because the oil is still leaking in Combustion Compartment.

Also, its not really complete info, but others might also add to it, clarifying it more.

8k is a little high for such a work, but i think this is including the Cylinder Block change, and other petty stuff. I got my work done, somewhere in 5k (If i am not mistaken). Labor was roughtly 700-800 (can't remember exactly). Also, I didn't change the piston so thats another reason why my costs were lower.

There are better (Japanese) parts available so find them first. Otherwise, AHL's genuine wil do.

[vicky_boy]

@vicky_boy!

If its the first time your bike is getting opened, then:
- Stock sized piston will work
- No bore will be required (You will have to ask them specifically NOT to bore it, unless absolutely necessary)

Bro i have consulted 2-3 mechanics and all of them said k ab bore ho ga aur 50 ka piston dalay ga. So that is why i decided to go with cylinder change it's the first time it's getting open and i dont want to take any risks. They might be able to shove the piston by hathori in the current cylinder bore but that would be a huge risk.
Besides the cylinder barrel is only for 1500 and kharadya labour is Rs400 so i guess it's better to spend extra 1k now and get the cylinder changed and avoid any risk altogether.
Also one more thing which i came to know (thanks to manual uploaded by you and r1) that cylinder also contains two cam followers which are engaged by pushrods so when i will change the cylinder they will take them out from old cylinder block and insert them in new block.
(pic attached for reference)

• you don't need to change the Cylinder Block, Valve Springs or Rocker etc.

Both rocker arms and valve springs are a big if depending upon their condition when taken out but they are most probably going to be fine as it's getting opened the first time and done only 35k kms

This is coming from my experience while getting Piston Rings change on my CG125. I opted not to change the Piston, thinking its fine and it'll work. Result, it needs work once again because the oil is still leaking in Combustion Compartment.

Yeah definitely piston is a must and one of the top priorities

8k is a little high for such a work, but i think this is including the Cylinder Block change, and other petty stuff. I got my work done, somewhere in 5k (If i am not mistaken). Labor was roughtly 700-800 (can't remember exactly). Also, I didn't change the piston so thats another reason why my costs were lower.

Yes this includes the new cylinder block, obviously this was an intial estimate as you know final kaam karwatay kami ho jati hai, this was quoted as the max possible

There are better (Japanese) parts available so find them first. Otherwise, AHL's genuine wil do.

Going through your thread i think i will only go for Japanese pushrods if i can locate them in rwp rest all genuine AHL