Valve Adjustment Notes
 

Completed my first RX3 valve adjustment. Here are a few observations.

On removing tank: after removing side plastic, and removing rear bolt, lift tank up at rear and pull backwards to release it from the front rubber mount. At this point there are a number of hoses that need to be disconnected if you want to remove tank entirely. For me it was easier to disconnect the two electrical connections, and set the tank down sideways on an old bath towel where the drivers seat goes. (Be careful to completely cover the starter relay and battery terminals: shorting the battery with your fuel tank would probably void CSC's warranty.) I used a second rolled bath towel to help prop the tank up so it was not sitting on the fuel connection, and I also put a strap around the rear of the tank down to the foot peg to ensure it wouldn't topple off. Had to be careful, but this avoided pulling lines off of the tank fittings and disconnecting the fuel injection line.

Taking off the cover and adjusting the intake valves was easy. I set mine at .004 inches. (Edit -- oops, should have been .04 mm to 6mm). But the exhaust valves were a different matter. CSC advises taking the radiators off of their mounts to give you more room for access, but I had difficulty finding a wrench that would fit the upper mount bolts: they are easy to see but the upper radiator hoses make it difficult to put a socket on them, and their position under the frame makes it difficult to get a wrench on them. (Edit: 8mm T handle like Spud suggests or an 8mm 1/4 inch socket on an extension works. ) So I tried leaving the radiators in place, got the cover off the exhaust valves, and squirmed around until I found a position where I could see the valve adjusters and get a hand on them. I eventually got a .006 feeler gauge under both, liked the setting, so I did not have to adjust either exhaust valve. (Again, oops -- should have used a .06 mm gauge!) It's better to unbolt the radiators.

As I prepared to reinstall the tank, I found a curved tab on the inner right frame member just where the fuel line "cannister" (the fuel filter) goes. Looked to me as if the tab was intended to secure a fuel line for a carb version of the RX3: it did not fit around the fuel filter and also would not fit into a slot on the side of the filter. I ended up bending the tab downwards slightly (its light metal and will break off easily), and just ensured that nothing was pinched as I reinstalled the tank. I considered using a zip tie to help secure the fuel line but decided against it.

Not a lot of problems. A couple of places reminded me that the RX3 is not quite up to Japanese fit/finish/assembly standards. Such as the curved tab that does not seem to fit the fuel injection line, and also a couple of cross threaded bolts holding the plastic in place. But its all back together and working well.

After removing the rear bolt from the fuel tank, I pulled the tank back from the rubber mount. Then I placed the tank on top of the rubber mount so I had enough clearance beneath the tank to unhook the two vent hoses, and the two electrical connections for the fuel pump and the fuel gauge. With all other hoses and wires disconnected, I then disconnected the fuel line from the fuel filter. As the fuel started to leak, I flipped the fuel tank upside down, and the leaking stopped. Then I moved the fuel tank away from the bike, and set it to rest in the upside down position. ;)

I used my Tusk Compact T-Handle Wrench Set to remove the radiator bolts. I believe I used the 8mm socket. I am sure one will find it very frustrating, if not impossible, to adjust the exhaust valve lash without getting the radiators out of the way. ;) The T-handle sockets make this job, and many other jobs very easy. :tup: I highly recommend this T-handle wrench set. :)

https://www.rockymountainatvmc.com/p...t-handle%20set

https://www.rockymountainatvmc.com/i..._t_han_wre.jpg

I use these T-handle wrenchs all the time while working on my Honda CRF250X. :tup: I don't know what I would do without these tools. ;)

Good suggestions Spud. I hadn't thought about flipping the tank to keep fuel from running out after disconnecting the fuel line.

Thank you for starting this thread, and sharing your experience. :tup: If everyone shares his tips, we can all learn from each other. :)

This theme is pure mystery, NovaRider said 004 "inch", but i research and coming ansvers is sad 004"milimeter" and 006 "milimeter" ...

Solved methodology : need a victim^^ a zero kilometer rx3 owner, and first job making for help checking the valve values.

Or need zs177mm " services manual " , thanks for topic.

The CSC RX3 Service Manual species the following valve clearances. ;)

Intake valves: 0.04-0.06 mm
Exhaust valves: 0.04-0.06 mm

Thank you:thanks::tup:

My mistake on the valve adjustment clearances. Thanks to Co2 and Spud for catching this!

There was already a discussion of this on the valve clearance sticky.

What threw me off was my prior experience working on cars and motorcycles. My experience is that .004 inch to .008 inch (often called '4 thou' or '8 thou') is a common range for valve clearances. So when I saw the .04 to .06 range for the RX3, I failed to look closely and just assumed we were talking 4 to 6 'thou', rather than .04 to .06 mm.

Also, when I just did my first adjustment, I found the exhaust valves were both almost exactly .006 inch, so that reinforced my belief that we were in fact dealing with 'thou' rather than mm.

In fact, the sticker on the RX3 indicates the range should be .04 mm to .06 mm. Just like the CSC materials.

.05 mm is roughly equivalent to .002 inch. I have that blade on my feeler gauge, so I plan to redo the valve adjustment and set them at a middle spec of .002 inch. Once I get a wrench to fit the upper radiator bolts, that is.

.002 inch is a tight clearance in my experience, but then this is a small displacement motor with four valves.

I've only ridden a few miles with the looser valve settings, which were close to the original settings anyway, so I can't comment on whether I was hearing more valve "tappy."

Mystery is'not end:hmm: service manual and adviced sad 0.04 milimeter(20/1milimeter?) intake , 0.06 milimeter exhaust
0.02 inch = 0.508 millimeters ? ( i understand this is a half milimeter?? )

My old and new filler gauge ( old start 0.05 and plus all 0.5 milimeter +++, but new start 0.02 and all 0.02++ 0.04+0.06+0.08....)

Values = 0.04 - 0.06 milimeter? i understand 1/20 or 1/18 mikrometer?? or im wrong ?

Again, best methode a new rx3 user helped this theme, and all know this, coorporations always hide this service secrets because need services maintenance payment, but me and other little village peoples non always finding services problem this:shrug:

There is an extra zero in the 'inch' figure. So it's .002 inch equals .051 mm. I think that should resolve the issue.

But thanks again for catching my mistake. I just reset my valves (and I did manage to get the upper radiator bolts out). I set the intakes to .002 inch, but went with a .003 inch gauge for the exhausts. Looser than the Zongshen spec (its closer to .08 mm rather than .06 mm) but close enough I think, especially since the bike only has 500 miles on it.

Maybe it's my imagination but it does seem quieter.

Thanks again for helping me through this. I feel like a noob again.

Needed a new feeler gauge
 

I turned 600 miles today and I'm planning on doing the 1000km service tomorrow.

I read this discussion and decided to verify that my Sear's feeler gauge had .06mm. It did not, so I went to the local Harbor Freight (open till 9pm on Sat.) with the 25% off July 4th coupon and picked a feeler gauge with .04mm &.06mm. I also got a free LCD flashlight.

Again Thank you. Wish me luck tomorrow taking the bike apart to get to the valves...and putting back together.

Good luck, Dave. :)

The first inspection/adjustment requires the most time. After you learn the tricks, the next inspection/adjustment will go much quicker. :tup:

0.04 Milimeter , 0.06 Milimeter values is CONFİRMED.

This my 3rd check valves story, but this time ok.

İmportant Note's : 4t motos 2x time find TDC(top dead center) , never try our hand skill (master skills) , every time moto block on screws remove and see all marks ok for tdc

Moto block down is camshaft/alternator/volant mark.

Moto block top 2 screw window is camsahft chain on marks as "IL" and "RL" marks .
follow and found, later adjusted valve's , other ways = damaged valve's , i experienced that theme :)
Good condition after 300 kilometer riding 0.04 and 0.06 mm sett new valves.



Have nice day's . co2.

The service manual for the RX3's colombian version (AKT TT 250 Adventour, carbureted) states the same: 0,04mm intake, 0,06mm exhaust.

Several service manuals available to us in the United States, including the CSC Service Manual, give the following specifications for valve lash.

Intake valve: 0.04 - 0.06 mm
Exhaust valve: 0.04 - 0.06 mm

I have been using these specifications for over 10,000 miles, and I am sure they are correct. ;)

Poor luck on my first adjustment
 

LOTS of trouble with this procedure today. I couldn't disconnect the electrical connector on the tank and couldn't figure out how to plug all those hose connections. So I left the tank on and got to the valvetrain from the sides. Not enough space for a vertical screwdriver so it was "rotate and pray" until the setting was right. I figure if my .051 mm gauge fits but my .064 mm doesn't, I'm OK. But those are really floppy feeler gauges...trying to slide one in the mostly invisible spot it has to go is, as we used to say in timber country, "like trying to push a logging chain uphill".

NOW, the bike won't start. It tries, but won't catch and run. So, did I get the valves too tight or too loose? Checked spark plug, etc. I suspect measurement error.

HELP, Magic Forum!

You may not have a valve problem if you truly believe that your adjustment was done correctly. Check your fuel connections as you may not be getting fuel. Inspect the spark plug to see if it's wet and make sure that you're getting a spark.

Thanks for the reply...plug was a little wet (not dripping) and plenty of spark (ouch!). I had so much trouble manipulating feeler gauges that I don't trust my settings. The valves seemed WAY tight when I measured them before the adjustment. The bike ran fine. Did I get them too loose?

I suggest you do the valve adjustment again. Here are a few tips to help you with the fuel tank. ;)

Go to your local auto parts store and get some 1/4" vacuum caps. The following package contains 4, which are red in color. ;)

http://www.oreillyauto.com/site/c/de...1167&ppt=N1171

http://images.oreillyauto.com/parts/.../47397-003.jpg

Work on the right side of the motorcycle.

Place an old blanket behind the fuel tank before you remove the bolt which holds the fuel tank in place.

Remove the bolt, and lift the rear of the fuel tank. Slide the blanket under the rear of the fuel tank.

Pull back on the tank to remove it from the frame. Rest the fuel tank on its left side on top of the blanket.

Disconnect the 2-pin connector which attaches to the fuel gauge.
Using a flat screwdriver, pry open the buckle connector which attaches to the fuel pump.

Remove the two hoses from the fuel tank.

Press the two buttons, and remove the fuel hose on the nipple which is pointing upward. Let the small amount of fuel drain from the loose hose. Place one of the 1/4" vacuum plugs over the nipple to seal the fuel tank.

Turn the fuel tank on its back. Press the two buttons, and remove the fuel hose on the other nipple. Let the small amount of fuel drain from the loose hose. Place one of the 1/4" vacuum plugs over the nipple to seal the fuel tank.

Remove the fuel tank from the motorcycle, and set it aside in an upright position. Now you will have enough room to adjust the intake valves. :)

Set all four valves to 0.08 mm. A little too loose is better than a little too tight. ;)

After the valve adjustment is done, replace the fuel tank by following the steps above in reverse. :)

OK, got it, Spud. I'll post when I get the new valve setting set. Thanks.

You're welcome, and good luck. :)

Spud's instructions are excellent (as usual!)

Just a bit of advice: Once you're done setting the valves, turn the engine over by hand so the valves are actuated. You'll see when you're on the base circle of the cam because neither the exhaust or intake valves are moving. Once you are at that point where both sets of valves are at their highest position (no load on any of the valves), insert your feeler gauge again and ensure you have the correct clearance.

As Spud said, looser is better than tighter, but too loose and you'll get a lot of valve train clatter.

Take your time, and take a break after adjusting the valves. Better to get it right than to do the job again.

ALRIGHTY THEN! Removed the tank and set the valves as per Spud. Learned a trick...take the feeler gauge out of the handle. It moves better that way. Set clearance tight with the .076 mm, and the .064 mm slid right in. Juggled all the hoses back into place and she started right up.

Thanks for all the help. I'll be changing oil and checking the chain tomorrow.

I'm glad you got the bike running again. :tup:

Yes, I always remove the feeler gauges from the holder. It is very important to do so with the smaller gauges, especially when used in cramped quarters. ;)

So when I turn the crank, and align marks in view hole on stater, must i turn clockwise or counter clockwise? One way is easier to turn, but I don't want to mess it up, you know.
Thanks for experienced advise here

Turn the crankshaft counter-clockwise. I always turn the crankshaft toward the front of the motorcycle, in the same direction it turns while the engine is running. ;)

Thanks Spudrider
Its so nice to get the real truth.
Thats the opposite of what the coffee shop guys just told me.
Back out in the garage I go.

GSC - just want to suggest that having the valve covers off and watching the rockers as your rotate the engine counter-clockwise is helpful as well. That way you can tell when both intake and exhaust valves are unloaded by the cam lobes and verify by looking at the timing mark.

That's a good tip. :)

I always remove the valve covers first. ;) After I rotate the crankshaft to TDC, I reach up and wiggle the exhaust tappets to see if I am on the compression stroke. If the tappets are tight, the piston is on the exhaust stroke, so I rotate the crankshaft another 360 degrees. :)

Rotation explanation
 

The reason it turns easier CCW (counter clockwise) is that when turning clockwise you are now engaging the roller clutch for the electric starter and trying to turn it as well.

It should not harm anything turning clockwise small amounts, but one should not do it a lot.

Congrats on your first valve adjustment!

Indeed, good for you. :) The first time takes the longest. The next time you will be done much more quickly. :tup:

I agree wholeheartedly with Spud, worked on a friends over the weekend and the 2nd check took less than half the time once I figured out how to hold the radiators (bungees) and send my arm between the front forks.

This bike keeps impressing me. Zongshen makes great bikes!

Thanks Jay and All,
Turning crank counter clockwise was the trick. My first time ever and with ya'lls help a total success. The 2nd time in this wknd I only pulled left radiator out of the way with a bungee.
1st time I must have had it on the exhaust stroke. Big difference huh?

Last week I installed heated grips @ BikeMaster and Enduro Engineering CSC's grip guards. Ready for winter riding now!
Thanks to you for being there for this rank novice.
Even Gerry at CSC wrote me back. And on a Sunday morning?

Yes, that definitely makes a difference. ;)

Ugh. I have the valve covers off and 3 valves seem too tight but I can't seem to budge the valve lock nuts. Using an 8mm combo wrench. Just what direction should I be turning looking down from the top?

The tappets have a conventional thread. Looking from the top, turn counter-clockwise (left) to loosen the lock nuts.

Good luck with your valve adjustment. :) Be patient, and take your time. The job will certainly go much faster the next time you do it. I'll be checking in periodically to see if you have more questions. ;)

Woodland sprite... I'm sure you've got it covered, but wanted to just say it (just in case) that all load be off the valve before you try to loosen the locking nut. (i.e. you should be able to wiggle the valve tappet slightly.)

Spud is correct... "lefty loosey, righty tight." It may be a bit tough to loosen, but if having difficulty, using another wrench (or hammer) on the wrench to tap lightly will help to loosen. Just don't round-off the nut!

Good luck!

Sprite, it you're using a combo wrench then you're not able to generate enough torque to overcome the production tightening. You should be able to get a socket on the nut, then use a breaker bar to loosen. Do not use a breaker bar to tighten, use a torque wrench if possible or get a feel for the torque on another nut then use your socket set to replicate. Good luck.

TDC indication.
 

I'd gotten tired of looking in to the hole in the alternator cover for the mark and remembered that the cam timing marks are easily viewed through the screw plugs in the head. :doh:

By watching for the "L" mark in the rear (intake) hole, you know you are just about to see the "R" mark in about 90 degrees crank rotation.

http://www.chinariders.net/showpost....16&postcount=5

Third picture down. Note,,,,,,, they're not really yellow.

Thanks everyone
I thought for a while I was going to have to come in here and post a plea to try to bribe AZRider into giving me a hand :P

Managed to get my hands a little dirty today without breaking a nail ;)

https://farm6.staticflickr.com/5636/...f4c86271f1.jpg

Got the bike apart, managed to dribble gasoline all over various things while the tank was upside down (didn't manage to siphon it completely dry) - luckily I remembered to buy vacuum caps so I could flip it back over after plugging the gas lines outputs.

I did manage to break the retaining tab on the bigger electrical connector - could not get it to release, then when I tried to "encourage" it by prying it up a little, it snapped. The connector seems to fit fairly snugly, so I didn't do anything to try to secure it better (I suppose I could have deployed some self fusing tape).

I wound up taking the feelergages out of the housing because they were a right pain in the you know what trying to get to the valves at the front of the bike. Speaking of which, those were THE WORST to try to get to what with the radiators constantly getting in the way.

I did not reseat the valve cover bolts with a torque wrench, but I did try to tighten them relatively snugly...the rear ones went on easily with a T handled wrench, the front ones...I managed to finally get a socket on them. As for the valve lock nuts, I was never able to get a socket on the front ones - the rear ones were reachable with the t-handled wrench if I remember right - I was seriously worried I was going to round them off the way it was going!

If anything, my valves might be a hair loose now, but I *think* 3 of them were on the tight side - either that or I was having issues with the feeler gauges catching on something. buttoned the bike back up and made sure it started ;) didn't get a chance to take it out for a ride - husband noted there was a lot of traffic (and likely distracted drivers) out this afternoon, so I didn't go for a test drive after I put everything back together.

Here's the proof that I finally got inside the bike ;)
https://farm6.staticflickr.com/5757/...9ab20766dd.jpg

Thanks again for being so helpful and supportive - it was an interesting day getting intimate with my zong ;) :hehe: