JacobSlabach

oh ok. I'm heard of a torque wrench, but never have used one. I guess I've just been lucky enough not to have broken anything off yet lol

5x10 is my guess lol those quads have to be more than 4 foot wide.

oh ok. so it should give compression specs in the service manual? Also have heard talk on 'torquing to spec' I assume you find the spec in the manual as well but how do you measure the torque applied to a bolt?

eh sorry- computer issues up there meant to say yes that looks like the head on my bike so thats literally exactly how i checked timing- t mark on the flywheel and marks on the cam sprocket. I'm thinking the tensioner is shot letting it jump time or the valves are incorrectly adjusted. btw, I was wondering how you find certain info in the service manuals? I find it hard to find the info I'm looking for and get lost lol

So I have rebuilt two top end's now and going through the process of a third. I'm confused about how high the compression should be on these atv engines, and if low compression, what should be replaced or checked and how? And as far as smoking, how to tell what is the issue there as well. The first rebuild i did was on a kawasaki 300 and it turned out ok... I realize that I adjusted the valve clearance on the exhaust stroke rather than the compression stroke which caused a tick. nut the thing that got me was one both rebuilds, the compession reading didnt really change that much. I've heard that engines should have over 100psi compression, yet have never seen 100psi reached on my tester by any engine. this thread is open to any top end questions btw.

I would check compression, oil, spark plug, and connections. when bikes sit, they tend to rust/corrode/dry rot and the electrical connections usually suffer. I had an old bike that didnt have spark and just going through the wiring and putting connection grease on the connection brought back spark.

if you replace the valve seals, I would recommend new valves as well as the old ones sometimes have a hard time re-setting into the head. Also, I have had two bikes with aftermarket carbs and am satisfied with how they perform. I say they are worth a shot at least, but @Frank Angerano and@06kfx440 have much more experience than i do.

yea those little Polaris bikes dont have fuel pumps i dont think.

another thing to remember is if you take a bolt out, especially those long ones that hold the head and cylinder to the crank case, never put the bolt back in if any liquid gets in the hole- let is sit overnight and air dry out. Have a relative that does automotive repair and she has cracked crankcases before because she torqued down a bolt that had water (or some other liquid) under it. That water is very powerful under pressure like that, hence it cracked the case and ruined the engine.

yes thats what my head looks like yes thats what my head looks like

ok. which manual should i get? I'm really not sure about the year or size of this atv

got it back together and started it up and it ticks worse now than it did before, thinking I dont have the timing right

the tires i run on my sportsman are kenda executioner 25in, great tires in/out of mud and dont ride rough on pavement either!

sounds to me like a badly adjusted carb. does it get better or worse as the motor gets warmer?

there were too marks on the sprocket that lined up with the head, no marks on the head. I took the cam sprocket bolts off and got enough slack to adjust the chain and put everything back together, still ticks, but worse now.

the cam was one tooth late of the flywheel.

the chain had good tension on it- not sure how to reset the tensioner on this motor tho- never seen a tensioner like it before. Also there isnt enough slack in the chain to jump it back like usual...how do I get more slack on the chain without taking the whole motor apart? btw someone was using their brain with this little groove in the flywheel bolt plug- I couldnt get the screwdriver to turn it without slipping so I just put in in the groove and gave it a tap with a hammer and boom, the plug turns loose. great trick!

looks like the cam jumped one tooth back. So just take the tensioner out and set it forward?

ok thanks! I'm just confused how to veiw the cam sproket? There is no cam cover and it looks like I'll have to take the head off the access it?

ok. I did not check oil as it looked fresh (clear and not musty smelling like moisture). I will check for oil flow with the q-tip. How can I check the timing and what should the valves be set to?

so how do I get to the cam and all on this unit? I see valve covers but no cam cover. And how do I check for oil flow? first time I've worked extensively on a honda so the engine setup is different and new to me

Stator tested good. Kill switch tested as not working (no reading to ground open or closed) I put clamps on the two bad connections one from the stater and one from the other side of the engine (might be the oil low/hot sensor?). I put the wiring harness back in putting connection grease on every connection as I went. Payed off cause I got spark. I put the plug back in and threw a makeshift gas tank on and up she started with no choke! The choke cable is locked up along with the rear foot and hand brake cables. It started with the kick-start, but it has a pronounced tick (sounds like a valve hitting the piston) so I think its out of time. How should I check the timing on this bike? I didnt see a viewing window for the cam on this motor.? so the next issue I'm tackling now is the tick. I did ride it up and down the drive and it did run strong in all gears and reverse. Btw this bike looks just like a '88 model fourtrax 350 i saw on YT

Polaris and yamaha. I know the scrambler makes a super fast bike but I dont think that will qualify in your type of race. I have heard good things about the yamaha raptor.

haha yea hopefully i can get a sportsman 850 or 1000cc at some point...

haha thing is one of my friends wants to buy it off me as soon as its running....oh well....cash first haha