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saddlehorse

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2009 Apollo Extreme 125.
New piston and rings. Now will not start.
Valve lash set at .003 .
Cam gear facing forward at mark and flywheel with piston
at top if cylinder flush.
Getting gas and spark .

What else could it be??????
 
make sure your cam gear is set exactly on tdc and the marks line up.. make sure there are no cold air leaks also (check manifolds are straight)
 
is the mark on the flywheel at the top ? eg 12 o'clock

also the exhaust clearance may be a little tight too,
they are recommended to be set at .004", but see how it goes when warm ?
 
The cam gear is dead on with the mark at 9oclock.
The case has no mark for the flywheel but flywheel has mark.
So what i done was lign the piston flush with top of cylinder and made a mark myself.
If you dont hold flywheel by hand it will turn back a little letting piston rest maybe 1/2inch in cylinder.

When you kick it over you can hear it loud through carb like a sucking sound that it didnt do before rebuild.
Atleast that i remember.

Thanks
 
so it sounds like it's 180 degrees out then

kick it over gently, till the kicker lever gets hard to push
then check where your marks are.
TDC should be very close.

i reckon there might be a timing mark on the opposite side of the flywheel to where you marked ?
 
yeah, i agree.. with the timing chain off you should be able to move your cam by hand quite a few degrees and not just a little bit (thats 180 out where both of the lobes are toward you)

also the flywheel will be dead up (where the mark is) it will be tdc with the flywheel mark straight up at 0 degrees (making sure the spark is close to the pickup to re-insure that its at the correct position) turn over by hand slowly and if it does one full revolution it should start
 
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The kicker doesnt get any harder it stays same .
Will try moving it 180deg and see what it does
 
on your flywheel, do you have a T and an F stamped into them ?
like what is shown here- how to find TDC


if not,
remove the spark plug, and turn the flywheel around while holding your finger in the spark plug hole to seal it off.
when you feel pressure from the hole, or hear the compression leaking out, then it is coming up to TDC
now put a long thin screwdriver carefully into the spark plug hole, and slide it down into the cylinder, so the end of the screwdriver sits on top of the piston.

now keep turning the flywheel slowly until the screwdriver comes out/up the furthest amount.
this is TDC, if you keep turning the flywheel and the screwdriver starts going back down/in again then you have gone past TDC.
 
The kicker doesnt get any harder it stays the same.
are you doing this with the spark plug fitted back into the head ?


Will try moving it 180deg and see what it does
to do this,
you need to turn the cam so that the mark on the gear lines up with the marking inside the head at 9 0'clock.
now undo the tensioner bolt on the underside of the motor, it will spring out and release the tension on the timing chain.
then remove the camshaft timing gear from the cam
the flywheel can now be turned around 360 degrees, (one full turn)
this is going to change the cam timing 180 degrees.

then refit the cam gear with the markings lined up in their correct positions, refit the tensioner and put the covers back on the head


So should cam lobes be facing back of bike , front of bike or what ?
at TDC, the intake valve will have just closed, and the exhaust valve will be just about to open
the high point on the lobes will be facing towards the engine, (back of bike)
 
does your cam gear have 3 bolts holding it to the camshaft ?

if so, you cant move the cam gear around 180 degrees because it wont line up with the bolt holes in the camshaft
 
Also after movin it 180 i sprayed some ether in the carb and when i kicked it over it sprayed the ether back out the back of the carb
 
i think the timing would be way out now then.
hopefully you haven't bent the valves, with them opening at the wrong time, and coming in contact with the piston


carefully turn the motor over now so that the cam marking lines up with the marking on the head
when you have done this, look at the setting TDC procedure i posted in post #9 above.
follow that and you shouldn't have a problem
 
Yes 3 bolts. I took cam gear off and turned cam 180 and put back together.
Will try your posting after i get back , heading to barn to work out the horses.
Thanks
 
save yourself the time.. take the top plate off the head (4 bolts) and have a look no lobes should be facing you and they should be facing the bottom of the head (therefor at there tdc) and then put the cam gear on with the notches lining up then take the spark plug out and with a screwdriver (not sharp) put it down the bore and the piston should stop you right up the top
 
Having no problem finding tdc . Have tried about every position possible on timing with no luck.
Fixin to call it lose and be done . I have pulled it aprt so many times to adjust timing with no luck i can do it in my sleep.
I have set cam with lobes towards rear , bottom , up and front and nithing seems to change.

Wandering if a valve isnt closing all the way or something and allowing it to do this.
 
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there isn't any point trying it all different ways.
there is only 1 correct position.

can you hear the compression coming out the spark plug hole when turning the motor over ?
 
Yes you can hear it from there. Can feel it from there and feel suction on the carb.
Took head off after work and cleaned valves. One wasnt closing completely.
Will try again tomorrow since i am workin horses again tonight.
 
if the valve isnt closing completely then you will need to adjust the clearances at the rocker arms.
set the inlet valve to .003" or .08mm clearance, and the exhaust valve to .004" or .1mm clearance.

hopefully the one thats not closing, hasn't been bent from being kicked over with the cam timing being out !
did you notice a shiny dent in the top of the piston when you had the head off ?
 
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