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Discussion Starter #1
I'm coming up on 18k miles on my '04 ST4S, and have a couple questions about the valve check.

A little history: I purchased the bike with just under 12k miles, and immediately prior to selling the bike, the previous owner had the 12k service performed at a dealer. Fortunately, I have the paperwork, which indicates the valves were adjusted, rocker arms checked, it got new belts and spark plugs. It doesn't look like any rockers were replaced, and there are no specifics regarding the valve adjustment.

Anyway, on to the questions:

First, I'm planning on doing the work myself, and I have LT's book, and have read much on the forums regarding the process. What I haven't been able to find is if it's possible to check the clearances without removing the belts? I would like to avoid unnecessary effort if the valves are in spec, so is it possible to check clearances without removing the belts? Also, what is the likelihood of the valves being in spec?

Second, are there any special tools that are absolutely necessary? Time and funds are a little limited as I have a trip coming up, so I'm trying to be frugal with both.

Thanks!
 

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You can definitely check the clearances with the belts on. If you need to change shims, much easier with the belts off and you can check the rockers for flaking.

The clearances could be ok but depends on what was done last time and how the bike was ridden. Normally the dealer doesnt change out shims until the clearances go out of the acceptable range. It the clearances were just within the range, then a some miles may put the clearances over the limit. I always set them to nominal as called out in LT's manual. If they are out by one shim size, then I change the shim. Keeps the clearances well within spec.

Concerning tools. You will have to depress the closing rocker to get your loaded, unloaded measurements to calculate your closing clearance. I dont recommend a screw driver as you can damage the valve seal below the rocker. How do I know this! I have rocker depressor tool or a nut driver of the correct size can work in a pinch. To change shims you will need to move the opening rocker over and to do this you need a rocker spindle puller or you can make one with 5 mm threaded rod stock. I have this tool also. To turn the engine over I simply put the bike on the center stand which lifts the rear wheel, put the bike in 6th gear and rotate the back wheel to rotate the engine over to get to top dead center to measure you clearances with the spark plugs out of course. If you have to change shims you will need a closer shim measuring tool as you cant accurately measure the closer shim without it.

See www.emsduc.com for more info and pics of the tools.

Mike
 

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Mr Leakered
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+1

For a first timer going at it alone, as I did last fall, you should leave about 20hrs available if you have to start swapping out shims. This would include time to sort out the valve measurments (BTW, keep everything in metric units), pulling the radiator and swapping coolant, changing out the fuel filter, and balancing the throttle bodies.

I'm due for the 30k service (similar to the 18k) in a couple weeks. I'm hoping to cut that estimate in half for this second go.

I also purchased a full set of Mike's shims from LT. The reason being, even if you measured correctly, the shim stack may give you a different final clearance than anticipated. Nailing LT's recommendations really improves engine operation.

It is a large initial investment, but the follow-on work down the road is a mere fraction then. Just think of the ROI as way better than the stock market. ;)

Good luck.
 

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Only special tools I use are the rocker depressor tool and rocker spindle puller as mentioned above. 6th gear and centre stand for engine turning.
The other tool that hasn't been mentioned is the pair of forceps required to prevent the valve from dropping when changing shims. So that makes three.

You already have the 4th special tool...LT's book.
 

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Having a tool to hold the valve so it wont drop down is helpful. If the piston is at TDC the valve will not drop all the way down as it will stop on the top of the piston. I dont hold the valve stem up. Therefore always important to change out shims when piston is at Top Dead Center. Another way to hold the valve up is to pressurize with air through the spark plug hole.

Mike
 

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It's useful to have the valve stay up when changing the closer shims. There is more clearance for the closer shim to drop down and allow easier access to the collets.

I use a big curved forceps covered with cloth backed adhesive tape. Avoid smooth tape; you can't get a good grip on the valve stem with the forceps. But any method that keeps the valve up is good.

Bill W.
 

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Discussion Starter #8
Thanks for the tips, guys!

Got everything checked, and they were all in OEM spec, so I'm not going to do an adjustment. At 24k I'll dig in and get everything to LT's specs. Now, I just have to get the TB's synched, and change the oil, and I'll be ready to rock and roll. :D
 

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Still needs a life.
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Thanks for the tips, guys!

Got everything checked, and they were all in OEM spec, so I'm not going to do an adjustment. At 24k I'll dig in and get everything to LT's specs.
They may not need adjusting at 24,000 miles either. Many have found that once the valves get embedded, they remain in spec; which is why many of us forego the intermediate (6,000 mile) interval valve inspections once the bike is out of warranty.
 

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Discussion Starter #10
Good point, and I've experienced exactly that with other marques, but I'd like to improve them from "Ducati" specs to "LT" specs... ;)
 

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Hold Down Tool

RodanAZ,

Just some comments regarding valve checks in general...

In 2k, my ST4s will be at 24k. I went to LT's specs at 12k. Skipped the 6k check. No valve retainer split rings were broken/replaced. One opener rocker. Also, considering 'embedding' comments I've run across, tried to reinstall the split rings in their original positions. We'll see where things are at soon enough.

This time around, a large standard screwdriver will be enlisted as the hold-down tool. Will notch and bend it. Already picked up a $1.99 sacrificial unit. A screwdriver was used at the 12k adjustment, but it did slip a few times. I was lucky and the valve seals were not damaged. The 24k adjust will not be done without the home made tool. As for the rocker pins, no special tool was needed to remove them. A few bolts and washers worked just fine. Go for it!

I used wire and forceps to hold the valves up. Overkill at TDC, but I'll probably continue the practice.
 
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