Finally, a linkage.. PSTO 125

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Also, further Supporting my diagnosis.. There is no smoke or much pressure coming from the crank case breather, Or the valve cap breather..
the only pressure there is the norm vacuum and i can assume under piston volume differences
 
If you have re used the rings before it is likely they didn't bed in, china motors hate old rings being put back in. Are you running a TB piston?
 
Phil67 said:
If you have re used the rings before it is likely they didn't bed in, china motors hate old rings being put back in. Are you running a TB piston?
Click to expand...
Yes Running my original piston from when i got the kit originally (prolly less than 5 hrs) or equal to...
Original rings are gone when the engine cooked the 1st time..
Replaced them with some new ones along with the valves and valve stem seals Just before going out for the ride yesterday..

If it was rings then the crank case breather would be smoking like hell yeah?

It could just be the oil rings but i dont want to take the bore off to inspect them, i will probably take the head off, and then rotate the engine after cleaning the bore and see if that lines the bore with oil.

I really think its just the seals.. i should be able to see when there off because the spring went black on the last ones that got heated..
 
****ing cam chain was loose.
Not very happy..
Pulled the head off.. valves look fine.. Will check if there bent at all.
No noticeable leaks with wd 40 + putting pressure on there on the intake side.
Exhaust leaks slightly i think and that is where it looks like the oil has been coming from.

Not happy. the chain still had life in it and was tight when i installed it. Guess i got lucky really.
Did notice a rattle, didnt think much of it as i thought it was just clearances.
Will take pics when its all apart... again. This time i will re-assemble with a brand new camchain. (adjuster was all the way out).
 
How the hell did it come loose? It must have stretched to buggery when you bent the valve last time?
 
Phil67 said:
How the hell did it come loose? It must have stretched to buggery when you bent the valve last time?
Click to expand...
Not sure, i know she wasnt in the best of nik before.. Maybe had 20% life in it really..
But really didnt expect it to become this loose.. it still had 3 or for clicks on the adjuster.. that should be no issue for a days running.

Must have deteriorated quickly..

Any way i have dodged a bullet however it occurred.. Will pull the valves out now and have a look see
 
DSCF2177.JPG
I found the bore to be in not so good condition, there were only a couple scratches before but not this many.. (all are barley feelable)

I found the top ring to be warn (not sharp) but the bottom ring was?

Not sure if it was the valve stem seals now.. but i may aswell replace them now i have it all apart.

before i pulled the bore off i cleaned the bore, held the cam chain and rotated the engine.. Every single time the bore came back with a coating of oil after rotating it and cleaning it a couple of times.

DSCF2170.JPG Thank god for that lol.. i would have been peaking if the head was damaged..

Now im at a loss.. the bore is pretty much unusable..
$$ tight at the moment but i may just wait a little while. Then get a 67mm? The crank feels tight enough (with the tiniest bit of movement) I dont want to split the cases.. was thinking maybe i can bore them out with alot of time and a dremel (using the new bore as a guide)

But then i would have to buy a new carby.. and clutch springs to keep up with it all...
At a loss with this thing at the moment. Cant even get jets for this carby..
 
boring out your cases wont be too hard.
remember WILL S here that did his CT110 cases, when he was doing a big bore set up for it?
he mentioned using a hole saw then flapper wheel
http://www.miniriders.com/jap-builds/40070-more-powah-postie-stage-1-a.html?highlight=crf150+piston



an AC-DC convertor is a rectifier, you need a regulator for it

didn't you have a photobucket acc?
when i click on your attatchments, they come up 5 times bigger than my screen(21" monitor) and are waaay out of focus
 
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my67xr said:
boring out your cases wont be too hard.
remember WILL S here that did his CT110 cases, when he was doing a big bore set up for it?
he mentioned using a hole saw then flapper wheel
http://www.miniriders.com/jap-builds/40070-more-powah-postie-stage-1-a.html?highlight=crf150+piston



an AC-DC convertor is a rectifier, you need a regulator for it

didn't you have a photobucket acc?
when i click on your attachments, they come up 5 times bigger than my screen(21" monitor) and are waaay out of focus
Click to expand...
Lol the camera had a hard time with this photo surprisingly this was the best result, Regulator thats the one i was thinking of.. (still need to find one)
also have one of them ready to go almost, now im going to wait for my wallet to supply me with some engine parts as so i can turn the crank easily :p

I think slow and steady will win the race with the dremel, some metal carbide bits.. to begin with and then smoothing to the end with the sand paper, will probably remove the engine studs too make this easier on my hands.. And will block the bottom of the case up with a rag or something to seal it off to stop swarf getting in there.

Got some work lined up in the coming weeks... So cant see this project waiting too long.. LOL i forgot i posted in the postie power thread i wonder how it went.. i will ask
i do have a photobucket account but uploading to here is same same..
 
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Its just a hole afterall, doesnt have to be pretty.

I have a 60mm barrel you can have that may be in better nick. TB piston included and new base and head gaskets. Want it? You just need new rings.
 
Phil67 said:
Its just a hole afterall, doesnt have to be pretty.

I have a 60mm barrel you can have that may be in better nick. TB piston included and new base and head gaskets. Want it? You just need new rings.
Click to expand...
Hellas yeah :) Thanks phill
Its either that or over a month of waiting or 150 for a stock bore here that just doesn't make sense when i can get a bigger one for 110 + a carby for another 60-70 plus postage..
Let me give ya $50 for the bore and piston.. Or atleast a 6pack of crownies or whatever you drink :p
 
It's YX style barrel, so the bash plate may need a spacer, you'll work it out.
 
xLOCOx said:
Gotta love engine probs hey? NOT! Did you reseat the new valves?
Click to expand...
I surprisingly didn't have to, The valves were spot on really :)
I actually dont mind engine problems too much, always something to learn a measure next time really :p
Certainly going to buy a new chain.. thats for sure
 
Okay, took the valves out today and picked up the other bore Thanks phill :)
The valves are fine and straight and zero leaks..
Partslist required for the build..
Some circlips (if i can get some from local shop if not re-use)
New rings
New valve stem seals
Dont forget the cause of all this. the camchain.

Hopefully getting them soonish but were not going to the farm this weekend so im less fussed
should probably be spending that time working on my car anyways
 
Got some shopping in today..
DSCF2192.JPG
ended up being a extra $20 for a new piston from a local store..
DSCF2190.JPG
A oko 26mm. i sold on the 26mm as because its a balance between too big for my stock bore (28) and too small for my to be 67mm bore (only slightly) And i would prefer to have a slightly under carbed bike i can pin from idle rather than something that hesitates from idle and needs to be nursed..

This leaves me with valve stem seals and a camchain to get but because of the impulse carby purchase i pre much have no funds atleast till next week :p
and yeah the carby came with the adaptor and the piston came with pin etc..

Dont know of a local shop that will sell me a camchain for my 155z and valve stem seals i guess i will give atomik a call and see..

Also need some jets for the oko.. its genuine so far as i can tell i will measure the slide to ensure.. Done 30mm, castings look okay thats verified to me :p

Should lend me some inprovement over the tiny scrappy moklt.. And now i can buy jets for it for when i do have finds for the 67mm kit
 
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the valve stems seals and cam chain are the same as what are used in a YX160 if that helps.
go for Viton stem seals if you can find them.
 
my67xr said:
the valve stems seals and cam chain are the same as what are used in a YX160 if that helps.
go for Viton stem seals if you can find them.
Click to expand...
Hey craig do you know what throttle cable i should be using?
the end of mine is a tiny little end that worked in the moklt but this oko looks like it needs a clutch looking cable end..
Its sitting in there quite alright now just wondering
 
yeah, personally i think they should have the clutch cable style end on them, but then it wouldn't fit down through the tube on the carby top.
the standard throttle cable end fits and works fine.

if you are using the molkt cable then it may need to be lengthened a little.
i had to cut my old mikuni throttle cables' outer back a bit so the cable would allow the slide to fully close
 
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