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690 SMC valve check/adjust (pics + questions)

138K views 197 replies 55 participants last post by  JunkYardJr 
#1 ·
Since the weather is going to be crappy for at least another week, I figured it was time to do the 600 mile valve check on the 690. I removed the 2 front side fairings, the voltage regulator on the right (for access to the right airbox bolt) and the air box.

To remove the airbox, you need to first remove the lid as well as the 4 screws that hold it in place (2 front, 2 back). You should be able to hold the voltage regulator aside to get to the right front bolt. Next, disconnect the 2 or 3 hoses that are connected to the air and the electronic sensor. Once that is done, just loosen the clamp where the air boot connects to the throttle body. You should be able to work it off pretty easily. Now you have the cylinder head cover expose. There are 2 hoses that connect into a metal dealie on the top, unclamp and remove them. There is also an electrical connector that kind of lays on top of the head cover, it helps to disconnect this. You can remove the spark plug while you are at it. I found the tools that came with the bike the easiest to use to do this. Here's a few pics of the plug. Certainly looks lean to me:




Now simply remove the 4 bolts that hold the head cover on. You might have to wiggle the head cover a bit to get it loose, but it should come off pretty easily.

Now you have the valve drive exposed and it's time to find TDC. To do this, I had the bike on a stand and put it in top gear. Roll the wheel forward until the valves close after the compression stroke. There also appears to be a way to identify TDC by looking at the cam. There is a line engraved on the backside of the cam gear that appears to line up with a bolt at the top of the head right after the valves close on compression stoke. Not only that, but the 2 outside holes on the cam gear line up perfectly with the rocker arm shaft removal holes (as seen in the first pic below. That way, you can remove the rocker arms without removing the cam. Can anyone confirm is if this method of the little mark lining up and the rocker arm shaft removal holes lining up is TDC?

Here are some pics.




Assuming that I am at TDC, I went ahead an measured the clearances. There is a label on the frame that gives the valve clearance specs. Both intake and exhaust appear to use the same specs which are .07mm - .13mm (approx. .003in - .005in). Can someome verify if this is the case?. Here's a pic (had to read it with a small mirror, then use photoshop to "reverse" it for pic):



Anyway, here are my numbers (valve orientation as if sitting on bike):

Exhaust
LFr = .102 (.004) - dead center
RFr = .102 (.004) - dead center

Intake
LRr = .076 (.003) shim= .255 - slightly tight
RRr = .051 (.002) shim= .260 - slightly tighter

So my intakes are on the tight side, time to check the shims. Remove the 2 bolts that hold the rocker arm shaft in place (circled in pic):



Here is a side shot of the intake valves:



Remember how the cam gear holes line up with the rocker arm shaft removal holes? I now took the longer rocker arm shaft bolt and, going through the right hole on the cam, threaded it into the rocker arm shaft a few turns. Next, simply pull out the shaft and you can remove the rocker arm. I removed each shim with a magnet and measured them with a digital caliper and got the numbers I listed above. There were printed numbers on the shims, but all I could read was the first and last numbers: 2 and 5 on the LRr shim, and 2 and 0 on the RRr shim. The digital caliper read 2.54 on the RRr shim and 2.61 on the LRr shim so I came to the conclusion that they are 2.55 and 2.60 shims based on the KTM part numbers.

If my math is correct, I will need the following shims now for my intake valves:

LRr 2.30 shim should make clearance .102 (.004) center
RRr 2.10 shim should make clearance .102 (.004) center

Can someone confirm if this is correct?. If so, I'm going to go ahead and order them from the dealer so I can get back to riding!

I am new to shim type valve adjusts so I just want to make sure that I am doing it right. SO far, it's really not much harder than the screw adjust type, just some more parts involved.

Well, I hope that I have done this right and I hope that these pics and write up might help someone else.
 
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#2 ·
Everything looks right to me.
You dont really need to be at TDC to check the valves. As long as the round part of the cam is against the rocker arm (ie the lobe is NOT on the rocker) you can correctly check the clearance.
You should check with your shop and see if they will just swap shims with you.
 
#3 ·
Thanks Mike. Swapping the shims is actually quite easy, I just need to make sure that I get the right sizes. I'm pretty sure that my math is correct to determine the sizes so I've just got to get them ordered. Might even try to get them from a Harley/Buell *shivers* dealer. :lol:

One weird thing that I did notice, if I roll the TDC mark forward just a little bit more, then I can fit the .102 (.004) feeler in both intake valves, very strange. Now I'm not sure if I should just go with that or the measurement at TDC. Nothing is ever easy... :lol:
 
#5 ·
No, the bike seems to run fine. I thought the same of TDC. I know for sure that i am at it now too as I did the "straw" test. At TDC the straw is as high in the plug hole as it will get, also the holes and mark on the cam gear line up perfectly (as I mentioned in the first post).

Again, out of curiosity, I tried checking the clearances with the cam lobes pointing straight down for the intake and then the exhaust. Now I get even different numbers. Exhausts are .006 and intakes are .004. Now I am REALLY confused.

If I use these measurements, the intakes are fine but now the exhausts are loose. What do I do??!?!?!?
 
#6 ·
690 Valve note:

The KTM maintenance manual confirms the markings that you are using for the TDC but you may want to fabricate a pointed bolt tool out of a m8 x 125 thread bolt to hold the motor at TDC. KTM sells the "special tool" but it is easily made and will prevent the motor from moving during the valve adjustment. Just find TDC as you have done and after removing the plug/bolt on the left side of the motor, feel the detent through the bolt hole or confirm it with a light and insert the hold-down bolt. DO NOT use this bolt as a hold-down to remove nuts such as the drive sprocket or clutch nut.
Also, I believe the shim size should be determined at TDC only and not at a variable off-lobe location.
Hope you're stuffing rags into all of the openings to avoid the "shim" in the crankcase scenario!
BTW, great photos and thanks for sharing. wayne
 
#7 ·
I do remember reading that some people used the pointed bolts to hold some KTM motors at TDC, but I don't know that it is necessary on the 690. Once the motor is set at TDC, it won't move unless you move the rear wheel. Also, where exactly does the bolt go?
 
#9 ·
Ok, I went ahead and ground down a bolt and threaded it in to hold the motor from turning. I didn't even have to move the rear wheel to get the bolt in the detent. Once in, I confirmed that the wheel would not move and rechecked clearances. Still came up with .102 for the exhausts and .076 and .051 for the left and right intakes, respectively. Going to go ahead and order the necessary shims. Thanks!

DRxDR, any comments on the fact that there are no washers on my rocker arm shaft bolts? The engine diagrams show that there should be some there, but I'll be damned if I can find any.
 
#11 ·
Thanks! I have searched high and low for pictorials for the 690 valve check/adjust and came up with nothing so I figured "what the hell...". I mean, it couldn't be THAT much different than other KTMs or other bikes for that matter. I'll try and snap a few more pics of the shim change once I get the new shims.
 
#12 ·
IIRC, The washers that you are referring to are for shimming purposes and if the tolerances are OK, then they are not required.
BTW, my valve clearance's were all at .004 except the right exhaust which had opened to only .0045 but are probably in need of another inspection. That first measurement was at about 2500 miles and I'm currently at 6500 miles. Definitely time for another look.
Also: You may consider removing the SAS system, since, as you may have noticed is a pain in the arse to disconnect each time. A simple resistor placed within the harness also allows removal of the air-valve, similar to the procedure used to eliminate the canister air-valve. If your catalytic exhaust has been replaced then the SAS is useless anyway but many owners prefer to not mess with the factory systems.
wayne
 
#13 ·
It seems a lot of the 690s have needed no adjustments on either the 600 mile check or at even 3000 miles. I'm kind of surprised the mine does. Oh well, no big deal to change out the shims. As for the washers, why would the rocker arm shaft bolts need to be shimmed? Just curious.

I had thought about removing the SAS system, but decided against it until KTM sorts the FI issues. I don't want anything to invalidate the warranty until the bike is running the way it should.
 
#15 ·
Ended up having to order the shims from the KTM dealer as the HD dealer didn't actually have them. Oh well. Anyway got them today and found that my math was WAY off. Turns out I just need 2 2.50 shims and that will take care of it. Thanks to the dealer for letting me borrow a few 9.48's to measure with. <- No, I didn't try to start the bike or anything with these ones. Got to order a few more now.
 
#16 ·
The valves are usually set tight on a brand new motor assuming they will wear in a little and loosen up. Tight is better than loose otherwise the valve might start hitting the piston. Yours probably just didn't wear that much. I bet that if you rode it that way until the next service it would probably fall into spec., 600 miles is not a lot of break in time.
The locking bolt is usually only necessary if your removing the cam from the timing chain. That way the bottom end does not move without the valve train. I just had to replace the cam on my 625:rant: When at TDC the valves should be at their loosest, anything looser should not be possible(on a single). I have a 4 year old, I always take the bike out of gear after I find TDC. Using the plug is a good double check and I suppose putting the locking bolt in couldn't hurt, unless you forget to take it out, however once you get comfy with the straw or your visual ref. on the cam it's probably just extra time.
The shims in various thicknesses are for lateral play, something you can only find in a service manual or when you get it figured out and update everyone with this great post. I checked mine when I replaced the cam and intake roller then shimmed as necessary to put it back in spec. That definitely quieted things down up there. If you look at it like, if you could move this rocker over here or there you can see that the rockers will start hitting things that they are not supposed to. The more lateral play the more quickly things will start to wear.

Anyway just my 2c.

:clap:You have done a fantastic job on photos and documentation.:clap: Once you answer all of your questions and refine the process you should be able to get it stickied. Something that is definitely needed for the 690's. If you haven't already check out "Creepers" guide to adjusting the lc4 valves. His instructions are posted over on KTMtalk and ADVrider. Maybe even here?
 
#18 ·
The valves are usually set tight on a brand new motor assuming they will wear in a little and loosen up. Tight is better than loose otherwise the valve might start hitting the piston. Yours probably just didn't wear that much.
Valves tighten up as they wear in not loosen up, so the factory sets them loose, and you are more likely to hit a piston with a tight valve than a loose one. They tighten up as they wear because either the valve starts to streach or the valve set wears a little causeing the valve to move up towards the cam which in return tightens the valve.
 
#22 ·
I could have sworn my manual said the first valve check was at 6200 miles.

Is that not correct?
 
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