still not running right

[Jabes]

so i finally got around to putting new rings on, got it honed out and everything and after it warms up it won't kick over if i turn it off but once its cold it starts 1st kick most of the time , im getting spark and everything and my compression is 110psi wen its wamed up... any idea wat could be wrong?

 

[Jabes]

bumpity bump bumpppppppp

 

[blasterman312]

that compression is low, you sure you have the right piston size for the bore after it was honed?

 

[blasternoob]

I had the same problem; "Went riding today and I have a problem" was my post. I never got an answer so I started thinking it was in the timing or the fire. I was going to pull my flywheel and check my woodruff key and stator. I ended up having to almost destroy my flywheel to get it off. In the process, I damaged my stator as well. To make a long story short, I bought a nice used flywheel and stator, put everything back together and it has been running perfect ever since. REMEMBER TO USE ANTI-SEIZE on your crank b/f putting your flywheel back on. I didnt use any on mine the first time and my flywheel felt like I had mig welded it on. (I also installed new full exhaust in the process. Not sure if this had anything to do with my cranking problem but I thought I would mention it.)


110 is not too low. i have exactly 110 compression and mine runs and cranks great! My brother's Blasty has only 80 lbs of compression and his cranks and runs fine as well.

 

[Jabes]

that compression is low, you sure you have the right piston size for the bore after it was honed?

yup we measured the gap after the hone and it was right

 

[Jabes]

anybody else?

 

[Kennedy_Power]

The compression is a little low; the engine is not broken in; the rings have not seated properly yet. You said you checked the piston to cylinder wall clearance; I am assuming you checked the clearance with a feeler gauge at the bottom of the piston skirt; and NOT at the top of the piston?
How was the cylinder honed? Was it honed with a ridged hone or a de-glazing hone that you could buy at the local automotive store? I am wondering if there is a tight spot in the cylinder. The tight spot could be from the cylinder being tapered or out of round. If you take apart the engine; you might see where the piston is scuffing the bore…
Good luck

 

[Jabes]

i measured the ring gap not the piston gap and we used a ridged hone i think...

could it be the TORS?

 

[ron89]

i measured the ring gap not the piston gap

i dont think u need to messure the piston gap just the ring gap ..

 

[Kennedy_Power]

Measure piston gap, I think your bore is tapered or out-of-round
Remove the cylinder and piston and do the checks to make sure thnigs are up to spec.
When you say we, how is we? If your dad is the we, he spent $800-1000 for the correct hone?

 

[Jabes]

we is me and my friend its his dads hone and its one of the ones that you put on the end of a drill that you get from the auto store for like 25 bux or so... wat should the piston gap be?

 

[Kennedy_Power]

Your bore for sure is the problem now.... Did you replace the piston or just hone and reinstall the old one? If you replaced the piston; was it the same size?

 

[ron89]

Your bore for sure is the problem now.... Did you replace the piston or just hone and reinstall the old one? If you replaced the piston; was it the same size?

nah he bought new rings for the piston cause the piston was still good ... why would that hone screw any thign up i did my yz250 jug with 1 and there was no probs..

 

[Kennedy_Power]

The hone is not going to mess anything up, because it’s not going to do anything, but de-glaze the cylinder wall. A flex hone; like you have; will just follow the bore to whatever it’s at. If it’s out-of-round; then it’s going to remain out of round. I would have the bore measured with a bore gauge; not sure what that is. Then check it out at sunnen.com
They are VERY expensive, like $1800
Maybe someone local has one.
Good luck, if you need any help feel free to PM me

 

[Jabes]

ill see if the place that did my bore last time can check it
thanks for the help

 

[quam]

be careful w/ those deglazing hones....i tried to do mine for the first time and i think i took too much off. which led to the piston having too much clearance (my dumb ass didn't check before reassembly) and flapping around in the cylinder. when i pulled it off it looked like this.

i had to crack the case and clean all the bits of metal out of it. which is good because i noticed a hole in the bottom of the ig side half.....waiting on my new case half for reassembly now.

 

[kylepotatoes]

i measured the ring gap not the piston gap and we used a ridged hone i think...

could it be the TORS?

It could be, try unhooking it.