Working on a valve adjustment and carb clean on my '94

Problem with your XJ? Need help with maintenance? Want to show off those new grips? This is the place.
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Joined: Thu Jul 18, 2013 2:23 pm

Hey, gang! I posted quite a while back, about my '94 XJ600S undergoing a carb cleaning. radare helped TREMENDOUSLY with his YouTube video series on the process, which was an absolute life saver. That being said - I've been having a lot of trouble getting the darned bike to run properly. It starts fine, even idles decently, but will not accelerate over about 25 mph. I bought the MotionPro manometer and did the carb balance thing as best I could, which didn't seem to help.

I did put in #20 jets that I bought from someone here years ago, and never got around to installing. After my third or fourth attempt at getting things to work, a couple weeks ago I took the carbs out yet again (getting pretty good at that, now - heh) and put the OE #17.5 jets back in, hoping for the best. Well, not much change unfortunately.

Our engines of course make some chatter when they're running in a healthy state, but mine seems to be clacking/tapping much more than it had before - which lead me down the rabbit hole of post-hunting here. Seems that I didn't think of a valve adjustment - whoopsie. :roll: I ordered the MotionPro 08-0017 valve shim tool from Amazon, and a metric feeler gauge and got to it, yesterday afternoon. First attempt at this, but... figured it out. I was referencing radare's walkthrough as well as one other, along the way. I had to rotate the crank around several times trying to get all the measurements done for intake/exhaust on all four cylinders, but got it documented. See attached pic.

This was going by radare's desciption of "they should slide in with some resistance" - essentially the last size that would fit. Assuming that is correct, above are the measurements as the bike sits.

This leads me to a couple questions:

1. How the heck does this shim tool work? :lol: I couldn't quite figure it out - it seems to be a very easy thing, but in my overly-tired state yesterday, it wasn't making any sense. (I shot an email to MotionPro as well, thought maybe they had a video.)
2. Ordering the actual shims. I don't have any need/desire to get a full kit for $150+, I'm just going to order the set I need. Is eBay pretty much the best place to go, still? I'm assuming that hasn't changed in the few years since most of the last talk, on the topic.
3. Here's the big one! I saw some comments about the reference chart in the Yamaha FSM and the aftermarket manuals (mine's a Clymer), being inaccurate. Is there an actual accurate one? If it's off by one row - in which direction? I just want to make sure I order the proper parts.

Thanks much. This bike first presented a gas leak in a carb seal about two years ago - I've been fiddling with it in my spare time, here and there for over a year now. Which is to say... I don't have much spare time, thus why it's taking so long. :)
I appreciate the help! If this valve adjustment and last attempt at carb balancing doesn't fix it, I may put it up for sale for a DIY'er who's better at this, than I am. If it DOES work, considering the emotional investment I've put into this, I may try and make some kind of cheap touring bike out of this thing. Which is kind of ironic, since I naked-ized it several years ago, so what wind protection it had, is now gone. Guess we'll see!

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