my bikes dying what could be wrong??

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The pic looks like a needle roller gone wanderring.Hot,lean,starving.Lack of oil.To prove a point,no carbon deposits are seen in your pics.Did you run it in right.Could be also a cracked ring through same predicament and harsh use during break in or cold starts
 
this happened to my rm125 wen i first bought it. It was jetted perfectly (so dont listen to just anyone, check the colour of your spark plug). The fool that had the bike before me put it into a shop (suzuki dealership) and had a new piston and ring put in it. (they f*%$%@d up)

Mistake no1 by the mechanic- Used cheap piston and ring
Mistake no.2 by the mechanic- Wen he slid the barrel over the piston, the ring wasent in the clip (rite position) on the piston.

Once the bike got hot the piston started to expand but the ring couldn't, this caused the bike to die (just like u've described). The ring broke in 2 peices and one bit went to the top of the piston and got hammered into the head. Im not saying this is wat happened but its a possibility.

U wont need a new head. But if ur handy with a grinder and sandpaper and a good quality polish you'll get those marks out no worries aswell as gain a bit of horsepower. However, if the ring has done damage to your bore, it will set u back well over 500 bucks. Dont take it to a shop they will rob u. If your barrel needs to be re-sleeved call or email serco, thats who dun mine. Get a CAST IRON sleeve put in it. They'll supply u with a full piston/ring/gasket kit all ready to bolt up.

I knoe its hard, but look on the bright side, while the barrels off u can port and polish ur exauhts ports (it makes a big difference to the top end ;))

Also pull ur reed block out and check it for damage or signs ov wer. (are they standard or aftermarket).
And check ur powervalves. If they are to close to the pistion/ring, they may have hooked up on the ring and ripped it off. (mine had to be grinded)

go back to standard jetting(this will be richer then paris hilton) and work from there, go off your plug colour and feel of the throttle.

Good luck man, hope this all helps and gets u bak riding,
 
thanks mxmad you have just gavin me heaps of info that is gona help when rebuild it,
hardafasta the reason you cant see any carbon deposits is cause i cleaned it a little to take the pic
i will take the bore off now an see what has broken an done the damage now that im thinking about it when i put in the new piston an ring one of the gudgen pins looked a lil out of shape an i put in boyesen power reeds maybe i forgot to tighten or locktite one of the litle screws
well im off to take the bore off an the reed block to see whats gone wrong ill lets ya know whats happened
thanks again all
 
wat sort of Boyesen reeds did u put in?
Wen i bought my Boyesen Pro series reeds they told me that most boyesen reeds make ur bike run richer. sooooo, u may not have to change ur jetting :)
cheers
 
farrk just took the bore an reed block off, the bore is fine an the reed block is fine too the ring is ok some little kinks on it an the gudgen pins are ok so i have No idea what did the damage to the piston an head!!!

BUT... the conrod doent want to go up an down smooth if some think broke down there could it get in the top to do that damage ??
an now how do i check whats going on at the crank shaft ive never pulled apart the bottom end before??????
 
You don't wanna try bottom end if ya have'nt got the tools ....for a start you need a bearing press but it's a pretty big job it'll cost you about $450 to $500 for a bottom end rebuild at the shop.

pull it to the top of the stroke and see if there is any up and down play in it , there will be a little side to side but you wan't f@ck all up an down .
when you say

" BUT... the conrod doent want to go up an down smooth "

could be big end bearing(bottom of conrod) , This is a bearing but I'm not sure if they can make it up top but you've definately had something flying around in there.....I've never had it happen but I've had needles from the small end bearing on the gudgen pin up in there before.

Good luck mate
 
it might be your cdi.. you say it was boggin i had the same problem....check all your wires....just today i came off my bike..tried to kick start it and it wouldnt turn over so i checked my cdi wires and then tried again..perfect. give it a try.
 
too late gav the piston an head got the **** raped out of them i dont know how?? i checked that maybe some thing came loose like reed block screw little end bearing or ring but nope none of that but noticed when i took the piston off that the conrod didnt want to go up and down smooth
i have gotton told that the big end bearing shat itself but even though it has i still dont know how that damage happend to the piston an head

but anyways my list of stuff to pay for is getting bigger by the day
$1000 fine
$1100 fix this problem with my yz an its fork seals
$????? parts to mod my pitty
far out my wallets empty i think ill go in the corner an finnish crying now lol
the things we do for fun!!
 
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