horrible ticking, need info!! PLEASE!!

[cbrdart_rr]

so we were out tearin up some ice yesterday, got a few good hrs of riding in, came back n loaded up to go get some food and more gas for the afternoon ride. got back to the river, unloaded and ripped down the channel, after i turned around to take off again, there was suddenly this horrible ticking sound, i shut it down and got pulled back to the truck. i tore into it last nite to see how bad it was. pulled valve cover n checked timing, good. as i turned the motor over by hand, it made a growling sound. i got out the stethoscope and listened and it was definitely not coming from the lower end. i removed the cover over the torque limiter and removed the torque limiter itself. i then turned over the motor again and there was no noise at all, smooth as can be. i turned on the key and hit the start button and the starter sounded fine as well. i looked the torque limiter over, but i dont know what its actually supposed to do, i realize that its a reducer from the starter to the flywheel, but is it actually supposed to turn or slide or anything? i see that there are clutches on the inside as well, so i imagine that when the starter is engaged, the clutches are engaged and in turn, turn the motor over, but then does the torque limiter just freewheel when its not engaged? is it possible that there some moisture got in there and caused the clutches to lock up or something??

any help or insight would be greatly appreciated!!

'04 yfz, stock internals
it was 5° yesterday, running fresh 0W-40 amsoil

[tsargent4]

damn why you running that expensive as amsoil...and ZERO WEIGHT at that? why not just use Valvoline ATV 10-40 oil?

[cbrdart_rr]

well if ya got it, spend it right!!? haha jk, i've always run amsoil in my 4wheelers and race bikes, i've seen too many motors that have had much worse wear while running other oils. i run the 0 weight when it gets down below 0, we had temps reaching almost -20 last week, its just a little thinner and doesnt break down once the motor warms up.

[tsargent4]

so whens the best time to run different weights of oil as far as temperature goes and keeping the motor properly lubed and not burning up the oil... zero weight, 10w40, and 20w50???

[cbrdart_rr]

i run formula 4stroke 10w-40 in the quad during spring, through summer and into the fall, when temps get down to 30ish, and the trails open or theres enough ice to ride the lakes and rivers, i usually switch to 0w-40 and i run that until spring, keep in mind that we ride even when the temps drop well below 0. i dont get much of a chance to ride during the sloppy months which is usually when the temps change drastically so this works for me. i run 10w-40 in the sportbike as well, in spring and fall, but usually during july and august when its hot and we're racing, i'll use 20w-50, but i dont find that i need that heavy of an oil in the quad. hope that helps a little, this is just what i go by.

[tsargent4]

well i have a 2005 yfz450 w/ a 06 motor and carb...with 10w40 in it right now and i can't get the ***** to start FOR NOTHING and its anywhere from 14-35 degrees out.

[cbrdart_rr]

do you change your jetting at all for winter? your oil shouldn't impact whether or not your quad starts either. try a few of the simple/obvious things, make sure your gas is on, and the choke is all the way out too, i have a buddy that has over looked that stuff more than once! what are your needle and jet settings?

[tsargent4]

i always start it with full choke and gas on...i have a full BUB Moto C-4 header and pipe and UNI air filter...I have 170 main, 42 (stock) pilot, needle is on 3rd from top (stock), and my air/fuel screw is 2 1/4-2 1/2 turns out I believe. My jetting is still off, I just don't know where to start because of the full exhaust. My air box lid has to be off as well.

[cbrdart_rr]

sounds to me like your pilot is too small, try a 45 or even a 48, a 170 sounds about right but you may need a 172 if its still too lean. your fuel screw shouldn't be out more than 2 full turns if you're running right

[tsargent4]

i have a 45 pilot i could use...the a/f screw is hard to get to w/ big hands even w/ a moose racing one...my battery was dead from the coldness outside...i charged it for 2 seconds and it fired up and is running great...but after it is warmed up and ready to go in idle position, and i blip the throttle it shoots a 3-4 inch flame and kinda pops a little...and when i kill it you can hear the quad shutdown and the exhaust kinda has a popping suction sounds..i do know the exhaust needs repacked FOR SURE...there's nothing left of the packing...any ideas what causes the flame or the popping and suction sounds?