Two-stroke piston change

[noobi]

ok,
well i bought a 2007 gasgas ec125
and the guy i bought it off imported it from south africa when they moved over here, and it was used by his son in cc and enduros
and i think this guy was really good, cuz he got suzuki sponsorship and thats why he was selling it, so its probaly been run hard
trademe havent kept the ad but it said that it had oil changes like every four hours and it was regularly stripped to frame and rebuilt, linkages regreased and what not alot more often that i thought was necessary maybe 20 hours or so??
but the guy was unclear about when it was last rebuilt or had the oil changed
so done the oil, but when would a suitable rebuild time be, doesnt have an hour meter, are there signs that it would need rebuilding so i can look out for them
it starts almost first time every time:2thumbsup

[xwhatsit]

Just throwing ideas around here, I know SFA about 2Ts, but can you whip the head off and check piston wear according to service limits?

[mattwood]

Just throwing ideas around here, I know SFA about 2Ts, but can you whip the head off and check piston wear according to service limits?

should be able to, its heaps easier than it sounds to!

[cheese]

mate for the $300 is will cost you, just change it and have some peace of mind.

[noobi]

should be able to, its heaps easier than it sounds to!

dont you just remove spark plug, undo bolts and have a looksi??


mate for the $300 is will cost you, just change it and have some peace of mind.


but its dad that needs convincing

so probably need symptoms that a rebuild is looming, can i do it myself or do i have to take it to the professionals?

[Reckless]

The guy was unclear....Means he hasn't done it for a while or it needs doing now.. usually?

Take a look at it soon I would say, just for the peace of mind! I have done only rings quite a few times but if your keeping it and its been raced do the lot. A lot of people would say for the cost of a 2smoker pistion always do the lot! Not sure about your ktm but a piston kit plus top pin and bearing should only cost $150-200. If you just measure the piston etc you still won't know how long the top bearing has been in and they can cause as much damage when they fail.
Then you know what its like for the next time and maybe then you might decide based on the type of riding you have been doing to only replace the ring at $30 odd bucks for a freshen up if the piston measures correctly and in the correct spot on it!
Unless your a top racer and don't thrash the heck out of it you can usually at least double the time the factory says pistons need changing in a 125. Secondly don't remove the head save yourself the gaskets etc remove it from the base of the barrell which will give you access to eveything you need. Make sure you strip and clean the power valve Assy and install it correctly when you put the barrell back on. A sticky power valve from 2stroke oil residue makes a 125 go like crap!
Only what I would do????? your choice.....

[Reckless]

but its dad that needs convincing
so probably need symptoms that a rebuild is looming, can i do it myself or do i have to take it to the professionals?


2 strokes often don't have symptoms, they go or they stop!! You can't tell if a 2stroke is Starting to blow smoke because of piston wear like a car engine because they always blow smoke! Tell dad they are about preventative maintenance. Small cost now saves big cost later!! Tell dad to do it all this time then your Dad is dealing with what you know, not guessing about what has or hasn't been done in the past???

[B0000M]

mate for the $300 is will cost you, just change it and have some peace of mind.


probably less. 125 parts tend to be heaps cheaper than 250 ones from my experience

[Rupe]

For the ec125 i'm pretty sure you will have to use a wiseco piston, and it might even be the same as a yz125, but I'd ask on thumper talk about that one.

Or call 03 3890080 and speak to Linton as he has a huge wealth of knowledge on gassers and is cheap for parts.

In my experience with gssers if you think you local dealer is charging to much, he prob is. You should be able to get parts at the same price as jap bikes if you shop around.

[scott411]

gas gas do run weiseco piston's but they are not always available though the weiseco distrubutors,

should be easy to find tho,

should be well under $300 for parts tho,

[cheese]

I just said $300 cause gas gas parts are fucking expendy normally

[barty5]

shouldnt be to bad but in saying that Rupecopp was quoted $400 for a genuine piston kit for his gas gas 200 from memory (and yes they run wiseco) i got it through sports pro for $149 just took a while although the dealer didnt have it either

[scott411]

sweet thats good, when we were gas gas dealers they could not source us pistons, good to see things have changed as the genuine ones were pretty expensive,

[Rupe]

shouldnt be to bad but in saying that Rupecopp was quoted $400 for a genuine piston kit for his gas gas 200 from memory (and yes they run wiseco) i got it through sports pro for $149 just took a while although the dealer didnt have it either


Yeah it did take a while, but I think the ec125 has the same piston as a yz125 which would give him a few more options. But check the yz125 thing via thumper talk or the gasgas forum (can't think of name).

And like I said if you shop around I haven't found any of my parts more expensive than jap stuff, some even cheaper. And a lot of parts cross over with jap stuff, one strange one was my rear sproket was for a dr250

[scott411]

year that sprocket fits husq's as well, most of the gas gas consumables are avaiable aftermarket and cross reference with Jap parts which is a good thing,

[theblacksmith]

shouldnt be to bad but in saying that Rupecopp was quoted $400 for a genuine piston kit for his gas gas 200 from memory (and yes they run wiseco) i got it through sports pro for $149 just took a while although the dealer didnt have it either

Hi mate - you got a link/contact details for sports pro?
Im after a piston kit for an old(87) kx125.
Cheers.

[barty5]

Hi mate - you got a link/contact details for sports pro?
Im after a piston kit for an old(87) kx125.
Cheers.

yeh i buy direct from them they dont deal with joe blog public i run it all through my workshop. Give us all the details oversize etc etc ill see what i can come up with.

[noobi]

i found the ad
http://www.trademe.co.nz/Trade-Me-Motors/Motorbikes/Motorbikes/Dirt-bikes/auction-153560342.htm

[noobi]

which piston would be best
http://www.wiseco.com/Catalogs/Powersports/EuropeanCycleATV.pdf

[Rupe]

which piston would be best
http://www.wiseco.com/Catalogs/Powersports/EuropeanCycleATV.pdf

the one that fits your bike, ring Linton if you are unsure of anything. He has tried most pistons in most gassers and knows what works best.

[krad_nz]

www.sportspro.co.nz (http://www.sportspro.co.nz)

Might have something on there...

[barty5]

www.sportspro.co.nz (http://www.sportspro.co.nz)

Might have something on there...

problem is you need to be in the trade to buy from them.
but their prices are good as with time to get most parts whih is why i shop there.

[Armitage Shanks]

Can't believe the 125's only go for that long, not being smart . I've been racing and riding YZ490,WR500 and KX500's for the last 10 years until recently and the big girls have lasted me over 80 hrs before a piston change and they never ( ever ) wear out, good luck mate. Less compression and a lower piston speed is probably why the dinasoars last so long.