This is my first ATV and my first real 2 stroke to mess with (I'm not counting weedeaters/blowers, because I usually get ticked off trying to get them right and just get a new one). I never have been crazy about 2 strokes, but the deal on this was too good to pass up, $300. Most of the machine is in great shape - original tires with plenty of tread, - body, seat, and all stickers look great.
But yes, there is a catch.....he locked-up the piston. The guy that had it is completely ignorant in mechanics. He apparently let the oil tank run dry, which is beleived to be the reason for the lock-up. He took it to a shop and after tearing down the head, cylinder,carb, etc. they wanted $1900 to fix it. He didn't want to shell out that kind of money for a fix and just went and bought a new ATV and paid them for the teardown cost and got it out in pieces.
Well now I've got it.
I've rebuilt trucks, smallblocks, and trannys, but this is new to me, so I'm asking for any good advice.
The bottom end rotated real smooth with no slack or slop, so I left it alone. I had the jug bored .020 and put in a .020 over Wiseco piston/ring/pin kit and a wiseco bearing. I had to file the rings slightly to get them to the gap needed (Haynes manual says .009 to .018). I put on a new oil injector line because the other was cut. Last night I assmbled the whole thing and everything went together pretty well. I started it today (40:1 gas + oil injector as the manual says for break in). The exhaust pipe leaks so bad it's tough to completely hear the engine noises.

Now here's the questions:
1) How rough is the engine suppsed to idle, it shakes pretty good.
2) I was told 2 stokes will make more 'knocking type" noises than 4 strokes. Is this true, because it is definetly making some, and if so how much is too much?
3) The tube from the oil pump to the oil injector is clear and I can see the oil in it, is this an indication that the oil injection system is working fine?
4) When taking off from a dead stop, it's pretty sluggish, is this typical?

Sorry this is so long, the rest will be a lot shorter. And yes there will be more questions coming. Thanks to anyone who read all this.

 

I don't know too much in the engine department, but I do know that my xplorer's idle pretty rough. A lot of shaking, a real uneven idle. So I think you're OK there. As for the takeoff, mine arent sluggish, but they aren't really moving that hard, either. They just make a lot of noise and speed up when they feel like it. No spinning tires without a good lean forward or something slippery underfoot. Sorry I can't be of more hope, like I said, I am engine-internals-ly challenged.

 

Thanks though. Any and all info helps.

 

aggiedaddy, the idle on most of the 2 stks is a little rough is it a 250. 300, 350, or 400? the 2s will have more noise than most, sounds kinda like a knock, as far as the oil pump goes, dont forget to richen just slightly for the overbore. and depending on any other mods (pipe, filter,etc) you may have to rejet the carb. as for sluggishness, could just be because fresh motor and not broken in yet.

 

It's a 250. So since I have the .020 over, you say I need to richen it up a little? I'll need to figure that out too. There are no other mods and unless I have to, I probably won't do any anytime soon (no extra $).
I'm not sure how the PVT is supposed to feel. With the way the belt and clutches are set up, I almost think that may be the sluggishness I have. It would seem it might take a bit of RPMs to get it engaged enough. Any thoughts on that?
Also, which way is the fuel switch on reserve/off/on? I have no label to indicate it.

Thanks.

 

The little 250 Xplorer may feel sluggish, especially in HI range. It should have LO and HI. LO should make it feel snappier. As said before two strokes(especially the 250) do make knocking and pinging noise. Did you bleed the injector as described in your manual? Smoke out the tailpipe is a good indication there is some oil being burned.

 

to richen the oil pump there are jam nuts at the end of the cable, the manual will give you all the info the to adjust it. its more involved than the 400 or 350 so since you have manual, won't take up a bunch of space. also, check you belt deflection. this can cause sluggish drive too. what yr and model is it. fishslab replied about the explorer, some fuel shut offs are diff. from yr to yr. one more, does the vibration/ shaking get worse above idle?

 

ooopps!! my bad guess i didn't read title too close lol. duh huh!!
your fuel shut off should be forward on, up off, back reserve.

 

It is a 2000 250 4x4 Xplorer that I got for $300.
It seems that it smoothes out, but it is somewhat hard to tell with the exhuast leaking so loud. The first thing is to seal that up so I can diagnose the other things better.
Ther was a good bit of smoke out of the pipe which has me thinking the oil injector is working. Because I premixed the gas, I figured there would be quite a bit if everything was working. I'm wondering if I should put straight gas in next time and depend on the injector working properly? I'm somewhat apprehensive about that.
Also, this is just an air cooled machine, but when does the fan turn on? I have a feeling the temp switch might be faulty. I jumped the plug and the fan works, but it never turned on while the engine was running.
I've got a bunch of questions, but I'm typing them up as they pop back into my head, so thanks to you guys answering them.

 

Mine fuel shut-off turns up/forward/down. So do you think down would be reserve?