i just adjusted the valves on my '02 250ES recon. intake was a little tight, exh was fine. whoever said this was easy...... it takes a long time to strip all that plastic to get to the point of being able to do the adjustment. I was wondering, on my flywheel, there were 2 lines marked fairly close together but neither had a "T" by them. then a little further on the flywheel (and it was really hard to get the flywheel to stop here), there was an "F", with a mark. I pulled the spark plug out and put a long screwdriver in the hole. it seemed the piston went a smidge higher to the "F" mark. just after the "F", the flywheel seemed pretty marked up, kinda scratched looking. Funny thing was, the valve gap didn't seem to change at either the "F" mark, or at the 2 lines on the flywheel. So which one is my TDC mark for valve adjustment??

also, the compression stroke is when you can wiggle the rockers a wee bit, correct? on the other stroke, they're stiff. it's hard, cuz i think i kept pulling the flywheel too much, so i was coming back to the same stroke (i.e. = 2 revolutions).

the spark plug i put in is a DR8EA. Honda recommends a DR8EA-9. What's the "-9" all about? I can't seem to find anything that specifies
"-9". Is the one i put in good enough?

While i got all this front plastic and gas tank off, is there any other maintenance i should be doing??Do i have to get headlight from Honda, they seemed to be made by someone else?

The diff fluid seemed awfully milky looking. is it possible to get mud/water in there? Is 80-90 gear oil okay? (Honda says 80W, but i don't think i've seen straight 80). Is it possible to heat this fluid up a little before changing it (like riding around in 1st gear), or does it always stay pretty cool and thick?

LAST Q!! The carb spec is 2 turns out for the pilot screw, set the idle to 1450, adjust pilot either way till RPM drops 50 or 100RPM, then turn it back out 1/2 turn from there. Right now i just got it out 2- 1/2 turns. Problem is, to do these fine adjustments, i always burn my hands in those tight quarters. so what do you guys have your pilot screw set at?

oh yeah, on the throttle body needle, mine is set in the middle of 3 positions. where should it be, or what difference will it make if i go up or down from the middle?

okay, that's a lotta Qs. thanks for any/all feedback. On our first ride recently, this thing was horrble for stalling. I think plug gap was too tight, and pilot screw was in too much. I ended up choking it lots to run. it was a slow, technical ride, so lots of stalling and very frustrating. when i pulled plug, it was quite sooty (coulda been from all the choking i was doing to compensate for lean mixture), and top of piston inside spark plug hole looks pretty carbed up.

 

bump.

 

More than you ever wanted to know about spark plugs:<a href="http://www.ngksparkplugs.com/techinfo/spark_plugs/techtips.asp?nav=31000&country">

http://www.ngksparkplugs.com/techinfo/spark_plugs/techtips.asp?nav=31000&country</A>=

In the FAQ section, there is a table of what all those spark plug numbers mean. The last number is the gap. I guess if there isn't a last number, the plug is ungapped at the factory???

As far as the rear "diff" (it really isn't a differential as the thing has a solid axle), the owners manual calls for 80W, yet all Honda sells is 80W-90. That is what I use. Ride the bike a while to warm the oil up and make it thinner, before draining. If you have any suspision that it might be contaminated, change it now!

 

great, THANKS. The gap...duh!! that makes it easy. i agree on the diff (axle), it barely holds anything, so cheap to change.

any thoughts on TDC mark, or carb settings?

 

Everyones mixture screw is gonna be a bit different, the weather, humidity, and altitude effect where the optimum point is. Here in MN, it varys almost 1/2 turn between the summer setting and the winter setting. 2 to 2 1/2 turns out, is a good place to start from. I use a #4 flat driver bit, and my fingers to adjust them. They make special, right angle screw drivers, especially for adjusting mixture screws, because some of the big 4 cylinder 4 stroke road bikes are a real pain to get at, but they are expensive. If its because your hand is big, you could coach one of your kids on how to do this. I have small hands, and sometimes i dont have much room.
The third slot on the needle is the factory setting, and as long as you dont have drivability problems in the mid throttle settings, it should be good.
You got the right idea...if you can wiggle the rockers at tdc and the mark lines up, its the compression stroke. You can also just watch the valve stems, and when the rocker is slack, then you can adjust it,... the mark doesnt have to line up. heres an article on generic valve adjustments, on motorcycles, which is very similar to quads.
valve adjust
I would think , that one mark is for the valve timing and one mark is for the ignition timing.
If the rear diff fluid looked milky, then Id think there was some moisture in it. Check the vent line on the top of the diff..for leaks or being hooked up.

 

thanks for the info. the valve link is good, cuz they tell ya being out by 1/1000 prolly isn't gonna be the end of the world. and as you get to TDC, there is a bigger range than you realize where you can adjust the lash.

my Honda manual shows 5 spaces on the throttle needle, but there are only 3 on mine. it was set in the middle so i left it there. also, manual says middle spot.

I'll play with the pilot screw, maybe I'll put on those mechanix gloves to minimize the burns from the head.

I think maybe all my problems were from a combo of wrong plug gap, too lean mix, and tight valve. even when i floored it wide open before, it sounded like it was lacking top end. now it seems to scream more.

last thing= rear end fluid. do you guys use 80-90 Sythentic, or just regular 80-90 gear oil? prices at walmart are pretty darn good, so i could use either.

 

Its your choice, if you want syn or not. Its just a ring and pinion gear back there, as long as it meets the specs, hypoid gear oil. I use the synthetic, just because I ride them, from 10 F on up, and at 10 F the grease is pretty stiff. The synthetic flows better at cold temps.