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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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#92 ·
Just thought I'd post my valve check info.

2008 KTM 690 SMC with 9,306 miles.

Checked valves and all were within spec. Here is the breakdown:

Left Intake had a shim size of 10x2.65mm with a clearance of tight 0.102mm.
Right Intake had a shim size of 10x2.65mm with a clearance of a tight 0.102mm.
Left Exhaust had a shim size of 10x2.60mm with a clearance of a loose 0.102mm.
Right Exhaust had a shim size of 10x2.65mm with a clearance of a tight 0.102mm.

The Rocker Arm bearings seemed to have some wear on them, but nothing bad. They were smooth to the touch and rotated without any issues.

 
#93 ·
Everything I've read about the intake rocker bearing is that it may feel smooth when rolled while the rocker is installed but once taken off and some force put on it, it may bind up a bit.
 
#94 ·
Just did my check at 18,300 miles, and all valves were ~0.1 mm gap at TDC. :bannana:

I noticed scoring on both rollers. I thought I had a new intake rocker on the shelf, but I was wrong. Since I haven't heard any unusual top end noise like I was hearing previously before swapping out the intake rocker at 12K miles, I left both rockers in there with plans to replace both next valve check at 22-24K miles.

I put in a new spark plug, and I have a feeling that my hard start problems were because of a worn spark plug. Worn how? The tip was nearly gone! It had a little point, and the gap was huge. I'll post photos in a little while. Color and carbon coat looked normal so I'm not concerned about damagingly lean combustion. Spark cone was a golden brown color. :thumbup:
 
#97 ·
Yep, just put in a new spark plug. Bike runs great so far. Though, once it had a difficult time starting, and the FI light came on for a second as it was starting. Didn't flash, and went right off though.
 
#103 ·
When I first got my bike my head was loose, the dealer went in and tightened all the cylinder bolts. When putting the valve cover, he unknowingly knocked the decompression assembly. I took it home and it was really hard to start, i thought I was going to burn up the starter trying to start it. Took it back and if I remember right there is a spring or something that catches the lever as the cam spins that was disconnected. I have had no problems since then. You guy might have knocked the same thing loose?
 
#107 ·
Thanks for this tip. I definitely bumped that teeny wire spring off it's seat. Amazing that it's strong enough to actuate the decompression system, but it works like a charm now. Maybe there should be a sticky about this little gotcha.
 
#109 · (Edited)
I ruined my battery since I drain it flat 2 weeks ago (I forgot to turn off key for hour or 2 after I spent 30 min or more reading original maps). It will work but it will never have cranking power it use to have.

This does not matter, what matters is that my temp sensor is busted or at least it seams so. I measured resistance at round 30°C and it read out 1.2K ohm while at 10°C it shows 4.6K ohm and at 0-3°C (I put it in ice) it was showing 4.8k Ohm. Now I left it in fridge to cool it at -4°C and will report back on that. I also run bike without thermal sensor and it was staling. Then I put 3.6K ohm and it was still staling, with 15k ohm was running solid at 1750 rpm, with 10k ohm and its running like it should 1650 rpm no stalling.

I will have new sensor tomorrow so I can measure its resistance and compare/leave for future reference since I cant find any info in service or owners manual.

After I get this sensor fixed I need to test my custom Arkrap-EVO1 combination map...
 
#113 ·
Great thread, here is my contribution.

My bike has 7200miles on the odometer. 2008 KTM 690 SMC.

Checked it all out today, 0.004in fit fine on the valves at the front of the engine (front of bike) the rear valves needed 0.003in. I took off the tight side of the rocker, and put it back together. Put the bike in high gear on a rear stand and rocked the engine using the chain drive so that the cams would apply pressure to both sets of valves, then back to TDC. This confirmed that I am within spec, but getting tight.

The euro equivalent measurements are:
0.004in = 0.102mm
0.003in = 0.077mm

Knowing it is safer to err on the looser side (wear tightens these up), I will likely tear into it again before the next valve check interval.

I snapped this photo of my rocker arms also:





Clicking on the photos will take you to Flickr, I uploaded full quality so you can see it all in brutal detail. I checked the rocker arms for play and scoring. Mine we very healthy.
 
#114 ·
Auto decompression

ok is the auto decompression shaft suppose to be loose. I opened my head up a little to check yesterday and the shaft would slide freely and seemed very easy to dislodge again. Did want to fully strip if this is the case. but i am having a problem starting. i have to hook a jump pack to the battery everytime and its due the the compression. Any suggesstions
 
#118 ·
ok is the auto decompression shaft suppose to be loose. I opened my head up a little to check yesterday and the shaft would slide freely and seemed very easy to dislodge again. Did want to fully strip if this is the case. but i am having a problem starting. i have to hook a jump pack to the battery everytime and its due the the compression. Any suggesstions
It is common that you might unhook the decompressor spring by accident, The large hook with the holes on it should close by the force of the spring. (if you open it, it should return slowly)
 
#116 ·
What do you guys think? Replace the exhaust rocker?


Here is a video of the play in the bearing.... I said intake rocker in the vid but meant exhaust.


Not to shabby for a cell phone pic and video :rock:
 
#119 ·
Did my valve clearance check few days ago (engine @ 21 000km). Valves are in spec range and rocker bearings have same play as they did at 13 000km when i first check them and markings on them are even more polished so now they dont look bad as they did first time i seen them :). I will not change them yet...
 
#120 ·
tinkling from top end

Hi, can anyone help, my 2012 690 smcr makes a tinkling noise from the top end when it warms up, no noises from cold start. After my 600 mile service the mechanic said that this was normal, i'm new to these engines, having had 609's, 625's and 660's in the past and these were easy to quieten, is this normal. Also had open airbox lid, Akro end can and map mods fitted at this service.
 
#121 ·
my 2012 690 smcr makes a tinkling noise from the top end when it warms up,
Tinkling? :lol: Like peeing? J/K :D

Yes I believe this is normal. Mine and others do the same thing. There seems to a developing theory that the cam chain tensioners on these bikes suck. They are a hydraulic/spring ratchet hybrid. Some people have switched to a manual tensioner and report there bike is now sounds like a sewing machine while idling. Search on "manual cam chain tensioner" here and you'll find it. I'm actually thinking of trying one.

Good luck!
 
#122 ·
yeah - I'd be looking at the cam chain tensioner. I just replaced mine yesterday evening, so I can't report on anything long term. But my 690 E would sound fine at first start and then develop a pronounced metallic clatter/tinkle once it got hot.

It's been discussed in depth, bit basically there's a mechanism in the tensioner that is supposed to hold the tension setting when the oil pressure is reduced - like when you've a hot bike at idle. But this bit seem to be wanting and allows the cam chain to become slack.
 
#124 · (Edited)
Today i inspected the head because of autodeco being very loud

I found that the camshaft got 0,5-1 mm play (bike view - left-right).
Is this normal?

Edit:
Actually, everything in the head got play.
Camshaft, rocker arms, deco pin and deco weight.

I suppose that deco weight and pin shouldn't have play, while camshaft and rockers are normal

Is this right?
 
#125 ·
Just checked my valves today, all within spec at 15,215 miles (08). First service was done at a KTM dealer by previous owner, I don't know what the measurements were then. Easy job thanks to this thread, I would encourage everyone to do it themselves. It will be super easy the next time. my roller bearings looked ok also. I haven't been riding this bike very hard, maybe the guys that have been pushing the bike harder/doing track days are having more issues with the rollers?
 
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