trx42023

I've heard of spark plugs firing outside engine but under compression being bad (or too weak to combust). Would the starting fluid cancel that out though? Being easier to ignite.

I tried starting fluid to no luck, took fuel injection off to spray directly in intake and it will not even sputter despite having spark. Which makes no sense even if its 180 out it should backfire or something. Theres pressure coming out exhaust like it has good compression.

I find it odd it ran good before and ran after rebuild then now suddenly won't do anything. I took it back apart and checked to see of maybe a ring broke or something but everything is fine. With the plug out and spinning engine over it has a strong visible spark. It won't backfire like a typical 180 out or something. It will spin and spin and spin with nothing other than sound of compression out the pipe/suction at intake. Then after 15-20 spins it makes a huge boom out the pipe.

Hey guys I'm stumped and need some help. I have a 2008 420 electric shift that refuses to run. ATV ran fine but had a horrible top end knock. Put a rebuild kit on four wheeler and started it up. Ran quiet as could be but would not idle. Tried starting it again after reinstalling fuel tank and quad would not hit a lick. You can spin it over 10-15 times until it pops through the exhaust like 12 guage shot gun. Will not even sputter on starting fluid despite getting spark at plug.