Replacing Piston and Rings

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brettLo

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Aug 6, 2008
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Location
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Hey,

I think im due to replace my rings in my 140. However, i was gonna take it to a local shop to have it done, but i figured i might have a crack at it myself. As ive never done this before i was wondering if anyone has a guide or some advice on doing so ?

Thanks in advance
 
np anything you are unsure of ask away, rebuilding a top end is pretty easy, and with a bit of guidance anyone can do it :D
 
np anything you are unsure of ask away, rebuilding a top end is pretty easy, and with a bit of guidance anyone can do it :D

Hey,

thanks mate, yea ive never done it before. A local fella wanted $250 to replace them for me, and i thought it couldn't be that hard with all the support here on the forums etc. was just looking on DHZ and the rings and piston delivered is only 50 bucks, so it could be a great saving if i just have a dig at it myself i reckon!

I might order it from DHZ on payday!
 
Ordered the parts today from DHZ should get em in time to get it fixed by the weekend hopefully!
 
^^^ awesome man! have you got the right tools too? spanners, torque wrench, feeler gauges? oh and its probs worth changing the oil while your at it mate
 
^^^ awesome man! have you got the right tools too? spanners, torque wrench, feeler gauges? oh and its probs worth changing the oil while your at it mate

Hey man,

I dont have a torque wrench as such, mainly just the basics such as alan keys, spanners and sockets.. my feeler gauges are missing and i just changed the oil on the weekend LOL :bigcry:

Will i need to completely drop the fresh oil when i do this ??..im guessing i wont have to ?

U think ill get buy with those tools ? will i need feeler gauges to do the piston and rings ??.. or do i need to reset the valve clearances when i re-assemble ?
 
^^^ Drain the oil man and then just put it back in after if its still good! um its always good practice to do the valves after a rebuild, see if you can borrow some and a torque wrench from someone at the coast man, youll only need for like an hour or two
 
^^^ Drain the oil man and then just put it back in after if its still good! um its always good practice to do the valves after a rebuild, see if you can borrow some and a torque wrench from someone at the coast man, youll only need for like an hour or two

Hey,

Ok cool as, thanks man one of the neighbours will have a torque wrench im guessing. I should probably buy some feeler gauges anyway so I can replace the ones that went missing, atleast that way I can keep an eye on my valves a little more often too.

What kind would you recommend, the flat style feeler gauges or the offset type ?
 
So i just took my bike for a burn up and down my street for the first time since doing an oil change on the weekend, and it seems to be blowing nowhere near as much smoke as it was!

So now im wondering if i DO need to do my rings etc.

The motul oil i was using was is here and i replaced this with one from DHZ on my recent order which is this torco oil.

Oh well, i guess ill just have to try go for a ride on the weekend to see how it goes, but since riding it this arvo up and down my street its blowing no where near as much smoke as far as i can tell! and in the worse case scenario ill just keep the parts i ordered incase i do go for a ride and something happens. lol
 
It shouldn't blow ANY smoke at all so id still be getting your hands dirty and replacing em to prevent further damage ...
 
Ok, so im almost half way there! lol

Im up to taking off my cam sprocket, but have had to stop because i dont have a 9mm socket or ratchet to suit and cant crack the cam sprocket bolts!:angry-smiley-013:

I'll try get my hands on one tomorrow, and post back with a heads up when i can :)
 
Right so the old piston is off/out and the new one I have seems to be the 55mm piston which I'm guessing is 5mm larger then the stock one in my Lifan 140.

Also the rings on the new lot seem slightly different and I'm a little confused.

Firstly, on the OLD piston and rings there seems to be a metal grate like ring on the very bottom, followed by one steel ring, then the top one (near the head of the piston) is thicker.

However, to be brief, the NEW piston and rings have two of each! Except for the "metal grate type" so I have that one in place on the bottom section, but coz there is double the amount of rings I'm slightly confused what goes where, and if there is a certain way each one goes ??

If pics are required let me know I'm replying here on my phone at the moment so my apologies.

Thanks in advance!
 
Ok so i noticed on the old piston and rings, that there is 3 rings, on the bottom - a metal grated type, in the centre a solid steel ring and same goes for on the top!

So my question is my new piston and rings come with a total of 5 rings, do i ignore the two in the kit that have the black on both sides ? and just set up the new piston and rings the same way as the old one is laid out ?? any help is highly appreciated thanks.
 
Ok so I have the new rings on the new piston, I have my bore atthe shop getting honed. But now the new Gudgeon pin that come with the new piston won't fit through the hole in the control arm thingy. Any ideas at all ? The old Gudgeon pin is to thin as it slips straight past the circlips *bangs head*
 

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