doing head, 54mm zongshen

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looks like it has been burning oil for a while or running very rich. strange it still has hone marks in the bore with that much soot in there.
where those clean spots there when you pulled it off?

what are you plans with the engine from here?
 
yer runs rich in top end, carby got a rly shit tune on it atm, will tune after tho,

plans clean the head up so remove the soot, port head and manafold, new valves, g2 cam, hd cam springs, tune carby right then,

emailed akunar before and got a answer back within 2 hours pretty much and said that they have got new valve springs in, that are "stiffer bigger lift versions"
that just mean can run a higher lift cam?
 
yeah bigger springs bigger cam.

are you doin rings while you got it open?

and you might wana consider changing carbs all together.. go an oko
 
ok thanks im onlying going to be geting the g2 and thats 6.2mm lift im pretty sure, know wat stock it??
and nar not piston atm, will clean the sool off it with the wire wheel tho, or should i jst dont worry about it?? with porting if i jst give it a lil sand with 1000 grit and then 1500 and then 2000, that should work well?? not after some full big port job, jst a lil to remove the bumps and drill marks,

should i get the head, steam bathed?? my bro said he take and get it done at his work, should do that after removing valves and port??

would love to get a oko but dont got the cash and cant find a 24mm one
 
i probly wouldnt bother with the soot on the piston. but the head yeah get it steam bathed.

as for the ports 1000 grit isnt going to do anything..
you need to use a die grinder and some stones or proper carbide bits.
the main area to work on is opening the exhaust port to the inside diameter of the exhaust gasket ring and same with the inlet port, match it to the gasket and also match the manifold to the gasket.
you could give the inlet port a once over but you dont need to get carried away. and stay away from the valve seats. you dont want to destroy them..
when ya get ya valves out put another pic up showing the area behind the valve..sometimes they have a bit there that could come out..

also check in the opening in the exhaust, sometimes there left with crazy amounts of weld in there.

as for the standard cam, i think 6mm is standard. dont quote me tho
 
oh and be sure to measure the length of your cam, im pretty sure theres 2 lengths kickin around
 
ok so what ur pretty much saying is to sand the bit of the opening ?? and not so much around the rest but give it a once over?? and port to match the gasket, <-- gasket being the intake carby one?

and yer ill take pic when i get out, need to make this clamp thing tommorm for that tho,

already checked that exhuast weld and couldnt feel any big welds sticking out, will re check tho
 
ok sweet, well i dont got a die grinder so ill jst get to wet and dry i guess,, will start with like 500 grit now
 
you may have to borrow one because your gona be there forever doing it by hand.
give it a go youll see what i mean

and as for the timing, just set it up standard..and work from there
 
yer ill try that if not then ill get one,

ill do a test to c if the valves hit the piston b4 i try and kick it to start, but if i spin fly wheel by hand and doesnt hit then should be fine to kick it??
 
as long as the piston is at top and cam mark is at 3 o'clock you should be right.
and remember this is the same setting for setting the valve clearance..

if there isnt a mark on the magneto for top dead center then now is the time to mark it. or at least check the marks as i have come across 1 engine that the marks were like 90 degree's out on the crank..
 
ok got the valves out, by making the clamp,

is the normal for vavles too be diff length??? ones 65 and others 66,,,

how do you removed the valve stems??? need to know quciky as its going for a stem bath tommorm

will post pics of valves and that soon
 
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valve steam seals,,

also got this as a reply and dont get it,,

You know it is possible to use std valves if you need to. The 6.7mm lift is basically right on the limit of the std allowance. Usually by taking out the spacers under the springs will allow it to get this much lift or a little digging will be needed. We will be selling the tols to do this shortly on an all new website but unless your a mechanic $250 for the kit is a little much to dig a mm. Have to be careful not to go to far or the valves will bounce obviously which is the other issue.

is he saying to run that cam and springs, ill have to remove spacer or shave the head?
 
valve stems seals just pop off with a screw driver...do it gently.

i wouldnt trust the standard springs with that cam, it would valve bounce before you got on the limiter..
also the springs would kill the head over time because the whole valve train actually rotates as it is running.

under the springs there are little shims(he calls them spacers) remove those before you send it off for cleaning or else you will loose them.(these shims are the ones he's referring to)

i think the tool he is referring to is to cut the spring seat(to fit long stronger springs in)..totally not needed in yours or anyones situation...just remember that akunar doesnt have much to do with china engines but he knows a bit about them because there honda copies..
 
ok so ill go remove the seal soon, ill do it softly,,
so pretty much hes saying to run the bigger cam and springs ill need to remove the shims/ spacers??
is this right or have i missed the hole thing?
 
no he is saying... if you choose to run the standard springs with that cam then remove those shims.(not advised) or the springs will bottom out(coil bind).

i wouldnt even think about doing something like that.

just buy the springs to go with cam...there is no room for error when mucking around with cams and springs...you can actually snap a valve in half is the springs are bottoming out.
 
ha ok sweet,, i was gonna get the springs any ways, ill email him back soon and the pics are almost done uploading
 

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