No compression!

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rach88

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Argh yes I know your all sick of me and this stupid pit pro. But now I did the oil change and now since then the kick start has no compression. I can hear everything moving. I'm taking a total punt guess and gonna think it needs a new spark plug? lol help! I dont think it could be anything major coz it run fine before the oil change.
 
well new spark plug is a good idea, can't hurt to have a spare.
but more than likely you'll need to set the valve clearance if you have no compression.
If valve clearance doesn't get your compression back up it's time to take off the head and check the head gasket.
all of these are very easy fixes, but get a new spark plug and do the valve clearance, that should fix it. don't just do one or the other do BOTH. then as a last resort check the gasket.

good luck and let us know how you go with it
 
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is this a start in neutral only engine? cant remember what bike you have...sorry
if so it sounds like the clutch cable is adjusted too tight or jammed

theoretically there are only 2 things that it can be in yr situation...

no spark plug or clutch cable to tight(kick in neutral only models)
 
yeah i just adjusted the clutch.. got some more noise out of it... but it still won't start. Still has no compression but.. its so easy to push down i can do it with my hand. its a pit pro 09... no sure of the actual model coz i got it second hand. its 150cc lifan. I'm freaking out at the idea of setting the value clearance! i have totally no idea what im doing! my friend is coming around tomorrow to do something to the spark plug.. hopefully i can convince him to do the rest :D
 
it's easy, only takes 15mins and is really hard to stuff up. here's a bunch of guides all of them are good and each one has good info that the rest don't.

I think this is the best video showing how to do it: YouTube - How to check valve timin on Honda 50 70 cc motors

here's a guide made by one of our members: http://www.miniriders.com.au/motor-tutorials/24965-how-set-valve-clearances-horizontal-engines.html

another good one: QingQi (Qlink) 200GY Illustrated Valve Adjustment - MyChinaMoto

after looking at all those guides you should have a pretty good idea of what you need to do, good luck
 
oh ok, 150 lifan will start in any gear so the clutch cable shouldnt effect it.

i think from memory they have a decomp setup on the cam, it could be that..

put it in gear and push it to see if the compression is there or not..that will rule out problems with the kick starter itself

this problems seems very strange....
 
probably the anti kickback crap holding on. try popping it in gear and rocking it forward... its weird on my 140 where i can kick it five times with nothing then...wham. theres compression...

mainly cus if all youve done is an oil change, it cant be something too hectic...
 
so can the value clearance go outta wack just from changing the oil?
 
so can the value clearance go outta wack just from changing the oil?

no it would be unrelated
probably the anti kickback crap holding on. try popping it in gear and rocking it forward... its weird on my 140 where i can kick it five times with nothing then...wham. theres compression...

mainly cus if all youve done is an oil change, it cant be something too hectic...

I forgot about about that stupid cam, I get the same crap, sometimes can kick 5 times with no compression then next thing you know it's back, bloody useless thing
 
oh ok, 150 lifan will start in any gear so the clutch cable shouldnt effect it.

i think from memory they have a decomp setup on the cam, it could be that..

put it in gear and push it to see if the compression is there or not..that will rule out problems with the kick starter itself

this problems seems very strange....

What do you mean by it will start in any gear?? can i kick start it from any gear?
 
hey guys just an update. Today we changed the spark plug and could roll start the bikes but it was running poorly. We have found the cause of the poor compression.. its like at the front of the motor.. some thing is too tight or loose! I dunno.. but its going in to the shop instead coz i am too freaked out to touch it again coz im over breaking it. Have ended up spending 650 on the bike with rec rego, 20 to tranfser the reg, 6.50 for the spark plug, 22 for new filter, 45 for new front brake assembly, 50 on oil, 20 on brake fuild and now some more coz its still not going... im never trying to fix/make something better AGAIN!! buauhah... but i rode my braaap heaps today and reminded me why i love it so much more then the pit pro!
 
you right something is too tight, it's the valve clearance, you just need to set the valve clearance and it should be all good again.
if you take a pitbike to a shop every time it needs something fixed you'll have spent twice what the bike's worth in no time
 
still dontunderstand why it happened after the oil change...and @ 50 for oil, i hope that was 4ltrs of oil
 
well sometimes these things just happen, the oil change it probably completely un related to the problem

I hope it was 8liters, castrol activ 4t = $35 4liters
where'd you get $20 brake fluid? should be $10 max for some good castrol stuff
 
you right something is too tight, it's the valve clearance, you just need to set the valve clearance and it should be all good again.
if you take a pitbike to a shop every time it needs something fixed you'll have spent twice what the bike's worth in no time

Yeah something like that values and crap buahha! I will just take the bike to the shop this once and get it going. Once it's all running fine I will just try maintain it well and hope I don't run in too much trouble for a while.

My friend has a cheap china bike and it's stuffed so we are gonna learn together all the stuff we need to know on that motor. Hopefully that way in the future i can fix it myself. Someone needs to like have workshops for this stuff... they'd get loaded off it charging people per class.

Going camping in the start of november and it's my boyfriends bike so I just wanting it going well asap because his only ridden once. Plus I wanna know its gonna be going good as we are going camping for a week and don't want it breaking down the first day!
 
if it helps any, when ya take to the shop let us know what they think.. theres alot of shonky shops out there that wouldnt have a clue and will tell you anything...like oh yr engine is fooked, or hmmm too much oil in it or sumthin like that..

but also it would be good to know the story for future reference....
 
Okay I just watched a really good easy to follow video on valve clearances so now I'm not to freaked out about doing that so looking forward to my next day off doing that. Just a quicky, I'm gonna do the clearance as .004 and .006 is that right?

But for now the actual problem I have been told which I can't remember what it is, lies under that plate..
lifan.jpg

I don't know the names for things so figured I'd show u what im trying to say buhaha.
So whatever is under there I need to make tighter to fix the compression.. anyone know what I'm talking about or what's under there? LOL

I'm gonna do this all on tuesday so now I wanna do it myself, so if there is any other simple lookin' stuff I should do I wanna do it! So gimmie a list :D
 

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