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DvDRip

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ok, you're half right. That's the rocker cover, the rockers push on the valves to open then, if there's no clearance between the rocker and the valve then you lose compression because the valve is being held open all the time. The solution is to set the valve clearance.
You don't have to remove the rocker cover to fix it, that what the valve inspection covers at the top and bottom are for. you should set them at .003 for the inlet valve (the top one) and .004 exhaust (bottom one).. make sure you don't get confused and set them at .03/.04
 

rach88

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sweet, so the valve clearance is all im gonna need to do? going to bunnings tonight to get that measuring tool.. so .003 and .004 so are those tools with the measurments a common thing aye?

I'm excited now because its my bf bike and his moaning and whining that he wants to take it to the shop and now i dont even think im gonna need to! yay. Thanks everyone... but i probabaly shouldn't count my chickens before they hatch so I'll tell ya how it all goes after tuesday!
 

DvDRip

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well if you've been playing with the carby you might need to tune it up after the valves are done. that's easy if it was running good before, just get it idling good using the mixture screw, then get the needle in the slide in the right setting.

yea they're called feeler guages, you can get then at supercheap or bunnings for about $10
 

sean01

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lol, can i jump off topic here for a tick...(no harm intended of course) but why is all this left up to you?
is your boyfriend scared of oil or something lol....maybe you's should be doing it together so you's both know for next time...

if its just not his thing, then thats all cool. i just thought it was a strange....
cheers
 

rach88

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yeah i have been riding for a couple of years and my dad has always raced gokarts so I have always been a real tom boy and wanted to learn about the engines and servicing. My bf is an accountant so his not all that interested. At first he hated when I got a ttr230a for the road and was very relieved when I wanted to start riding pit bikes again. So it's taken a lot of pushing to even get him riding, I was very surprised when he was willing to fork out the cash for it haha! But now he likes it after riding mine... so not gonna push it on him to much. I kinda wear the pants in the relationship I guess hahah
 

headsmess

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lol to ^^^^^^^^^^^^

um, that thar plate encircled in pic is the...um...i suppose rocker cover would be the right term...but nothing under there thast adjustable... try not to remove it, cause those four nuts are the cylinder nuts... very handy for holding the head on :p

what wants pulling off for checking them thar valves is the two lil caps you can see in the pic...one above, one below :)

and, now...im just starting to wonder...possibly just the cursed anti kickback mecahnism causing grief? usually just a lil roll forwards in gear will fix em....pesky damn things that stick on and never really work properly anyways...
 

rach88

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its nothing to do with the anti kickback... i have checked all that and tried putting it in gear and everything. I will just do the valve clearance tomorrow and then let ya know... it runs fine when you push start it. Once it's been push started and warmed up it can be kicked start... i have sorta failed to mention that during the hole thread! whoops.
 

DvDRip

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it's usually harder to start once bike warms up when the valves are out :confused: but bikes are usually easier to start when warm to maybe it cancels out?
either way these engines need the valve clearance set regularly so you need to do it no matter what
 

rach88

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yeah i know. There is still no compression.. its weird how easy it starts once warm. Like get to tdc and just one small push and its a go'er. Hrmm. I will let you know tomorrow how it all goes. I just want to be able to kick start it because I know I sure as hell can't push start it on my own! If i can't fix it with the vavle's tomorrow will it help if i up load a video of what its doing?
 

DvDRip

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yeah i know. There is still no compression.. its weird how easy it starts once warm. Like get to tdc and just one small push and its a go'er. Hrmm. I will let you know tomorrow how it all goes. I just want to be able to kick start it because I know I sure as hell can't push start it on my own! If i can't fix it with the vavle's tomorrow will it help if i up load a video of what its doing?
yep pics and video's say a thousand words
 

sean01

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yep i for one would like to see the vid, because what youv described is it has no or very little compression which would indicate that the valves are held a shtload open...

after you push start it does any compression return to the kick starter?
 

rach88

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no it still has no compression but its possible to kick start it after its warmed up. i only started the bike once or twice before the oil change and it was just a normal hard kick start then. I will get some footage for you tomorrow if no luck. hopefully i dont have too! i really want it to be the valves!! we go camping on the 31st of oct and i want my boy to know how to ride it before we go other wises the hole camping week will suck coz i will always have to stop and wait for him to catch up! grr
 

rach88

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<a href="http://img94.imageshack.us/i/mov00161.mp4/"><img src="http://www.imageshack.us/thumbnail.png"/></a>

The video is pretty dam crap coz i did try tell the person tapping to get on the side of the bike but they were being retarded and then I got angry... so then I just took the anger out on the kick start... hard to hear anything as I did it on a phone.

I dunno whats going on because as you all mentioned it starts in any gear, but when I put it in first and pull in the clutch it still rolls forward when i go to kick start it as you'll see in the video. also when i put it in first and pull the clutch in the bike doesn't roll.

So after all i cracked it.. bf wasn't being helpful so I told him to do it his self. going to a mechanic on friday..
 

sean01

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yeah you can hear it wanting to start, and you can clearly see its down on compression. but from what i could see in the vid i dont think its totally gone...hopefully the rockers are all that needs to be fiddled with.

one question tho.. it may sound noobish...but which bolt under the engine did you drain the oil from.
theres one close to the gear lever and one sort of in the middle....pretty sure one is 14mm and other is 17mm?

just a question cause im wondering if you did the one closest to the gear lever and while it was out someone kicked it a few times there is the odd possibility that the timing chain has jumped a tooth...

but anyways if your over it then i understand if there no reply...
 

rach88

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I'm 99% sure i did the right bolt. The bikes at a mates place, so I cant check right now. We never kicked it while the bolt was out. I have this awesome feeling I'm gonna get ripped off where I take the bike coz they will know I dont have a clue what the prob is. Err.
 

sean01

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yeah i didnt think you would have done what i outlined above...i only asked cause its the only other logical reason well apart from the decomp mech on the camshaft....lets just hope the valves are it....

get a quote and all the details and post here for us to comment on if ya like.
 

DvDRip

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valve clearance, I'd say should cost about $15-$20. considering that's how much they charge for a tire change and it takes longer to change a tire then doing the clearance.
but then they'd probably need to tune the carby to get it running right and that could take as long as they want it to take.
 

rach88

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hrmm im starting to freak out. my friends el cheapo TDR just started to do the same thing, but it doesn't even sound like its trying to start. Took it in to get looked at and they told her something about the kick start being stuffed and its not worth fixing. so her only options were new motor or put on an ele start! I'm worried this is gonna be the same story with mine... but mine sounds like its trying to start... ARGHH freaking out... take it in hopefully monday. tell me what u reckon? I just brought this bike I don't wanna have to buy a new motor!!! Listen to the video and u can hear it turning over.. OMG PLEASE BE THE VALVES lol!!
 

DvDRip

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all pitbikes will start to do this after a while if you don't check the valve clearance regularly enough. if the kickstart on your friends tdr is turning the engine over then that mechanic's full of shit
 

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