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2002 KX125 Torque Specs?

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I'm doing the top end on my 02 KX125, and need the torque specs for the head and the cylinder nuts. I have read that it's 18ft/lbs for both, and I've read that it's 18 for the head and 25 for the cylinder. Anyone out there able to confirm this either way?

Thanks,

Dan

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Excellent. Thank you Sir. :p I don't think there is anything else torque-sensitive on the rebuild, but if anything comes up I'll ask. I'm comfortable doing things like the radiatior by feel :ride: If you can think of anything I'm missing that would be appreciated as well.

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I know a few people like that :p I'll actually be borrowing the torque wrench from one of them, since he doesn't seem to need it anyway! I have not done enough of these to have it down that well. Or maybe I'm just anal retentive about this stuff. Take your pick.

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This I know, but thanks for the heads up all the same :p

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alomst all kwi 2t's are 18ftlbs on the cylinder and head

125's not 250's. 250's are 25 ft lbs on the cylinder and 18 on the head.

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So I thought of another question. I'm pretty sure that it calls for aluminum safe coolant, I forget the details of the stuff but it's basically made for aluminum motorcycle engines. Mixed 50/50 with water, IIRC. OK, so since I could use verification on that, we'll call it 2 questions.

The real question is what does it call for as far as oil in the crank case? I drained both, coolant I kinda had to, since I was popping the head and I figured it was about time to do the crank case oil anyway. Is it safe to use blinker fluid in the crank case?

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Nowadays, most (if not all) coolants found in automotive stores are safe for aluminum since pretty much every engine has aluminum components today. 50/50 is fine if it is not already diluted.

There are a bazillion different opinions on transmission oil (not crankcase!). The crankcase (crankshaft, piston, connecting rod and bearings) is lubricated by the oil/fuel mixture. The transmission is seperate from the crankcase and houses it's own oil. Check the FAQ Sticky for questions on transmission oil.

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Thanks again. So coolant, basically whatever, double-check aluminum safe and mix 50/50 if not diluted. Transmission oil, read the FAQ and the bazillion other debated on the subject. Ick. I've been down that road, and didn't get much out of it other than a bunch of strongly-worded opinions that I didn't have the knowledge to sort the good from the bad on. That's why I was hoping to hear what the service manual suggested and just go with that. I'll check the FAQ though, I don't know if that was part of my reading last time I got into this. All I really remember getting from last time was a headache and confusion, with a touch of annoyed.

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Thanks. I'm half way through the tranny fluid/ATF/some guy with a 4 stroke chiming in on a 2-stroke thread and I'm already slightly irritated. I guess it comes down to

1) what the manual says (man, that' sa lot of letters and numbers, I'm going to have to bring that post to the parts store with me if I go that route)

2) Type F ATF

3) Blinker Fluid.

I'm kinda partial to blinker fluid.

Also, I actually broke a gear in an old CR125 I had when I was a teenager. I never realized it was due to my choice of transmission lubricant, I always figured it was beating the heck out of the thing with my overly agressive riding habits. Learn something new every day!

As an aside, I have a buddy who runs heavy gear oil in his CR250 & YZ250. Never even heard of anyone but him doing this. Be interesting to see how that works out. Personally, I'm going to stick with one of the 3 options listed above. Probably #3, since I need to change it in my truck anyway. The side marker lens broke when I bounced it off a rock in the woods, clearly a case of being low on blinker fluid.

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stupid question time, if you happen to jump online and have that manual handy. Actually you probably won't need the manual for either of these.

1) Arrow on top of (Wiseco) piston facing front of bike?

2) Does it matter where the gap in the ring is facing at time of reassembly?

Thanks,

Dan

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Arrow to exhaut/front

There are small locating pins in the ring groves on the piston, that's where the gaps go. Be careful not so snag a ring installing the cylinder.

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Wow, that was a quick response! Thanks! Just grabbed the new piston/ring, and there is indeed a pin type deal in the slot that suggests the location of the ring. Awesome. Thanks again!

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Mind digging out that manual again to hook me up with a few more #'s? I'm wondering the OK range for the clutch plates and springs.

Also, if you happen to get to it today, knowing what size sockets I need to grab with the torque wrench to get the head and cylinder to spec would be nice as well. No big deal if not, I can check tonight and grab the wrench tomorrow.

The rebuild went swimmingly, by the way. Until the rebuild yesterday my bike made 0 power anywhere but WOT in powerband, so it spent a whole lot of time there. You've gotta work the clutch to ride a 125 anyway, but this bike was way worse than most. Fresh top end, carb rebuild and some clean powervalves later it actually makes a touch of torque... as much as you can reasonably expect from a 125 anyway. It can be ridden through a flat trail outside powerband now anyway.

I think my biggest problem was the powervalve. There was so much gunk on it that it was literally one piece. Couldn't tell by looking that it was supposed to be 2 moving parts. It was clear it had not moved in a very long time. The valves could not even be pulled apart by hand. 1 Solid clump of junk, to the extent in addition to being bound in position you couldn't even tell if it was rubber, plastic, metal, or what.

I cleaned everything to surgical specs before reassembling anything, so I can say with a fair degree of certainty there are no leaks. First kick, runs great… overall a complete success.

Thanks for the help.

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