Finally doing my valves: Question, please...

[TeeCat]

Hi, friends.

Hey... TC is finally doing his valves!

The covers all came right off okay, and even the gaskets look good, so I might as well save my new ones.

'k, question:

IF I'm right at TDC on each cyl - I am using the method of feeling for slight (gawd, it's tiny!) play in both tappets on the same cyl - here's what I have:

- the left intake will take a .003 with very light drag
- the left exhaust will not take an .006... seems quite tight
- the right intake will take an .003 with loose drag, and an .004 is tight
- the right exhaust seems really tight.

Now, I'm ONLY going CCL to keep tension on the chain, but I'm still a little doubtful about being RIGHT AT TDC on the compression stroke. I know it can't be a very wide range, but I'm kind of concerned about doing the actual adjustment and possibly being ever so slightly in the wrong place on the cam. In any case, the tappet movement that I feel is so tiny, so is is safe to "feel" your way though this this way?

I can't really see the piston action in there, even with a light, and I'm reluctant to stick anything in there... I'm out of knitting needles...

So, TDC. What do you guys like to see/feel in terms of TDC before you make that adjustment? I'd hate to wind up with them too tight or too loose after this.

Off to get a 4mm or tiny adjustable wrench now... I only have down to 6.

Thanks!

TC

 

[5twins]

Are you checking all 4 valves at the same time and at the same TDC position? You can't do all 4 at once, only one cylinder's valves. The pistons rise and fall together but at TDC, the 2 cylinders are on different strokes. One is at TDC on it's compression stroke and can have it's valves checked/set. The other cylinder is at TDC in it's exhaust stroke and can't have it's valves set. Both should be tight on that cylinder with no play. The exhaust valve has just finished closing and the intake is just about to open.

You need to determine which cylinder is at TDC on it's compression stroke, set it's valves, then rotate the engine 360° to TDC again to place the other cylinder at TDC on it's compression stroke. Then you can set it's valves. I find the easiest way to determine when a cylinder is at TDC on it's compression stroke is to watch the valves operating while you rotate the motor. Start with the left cylinder because you can easily watch it's valves as you turn the nut on the alternator. Watch for the exhaust valve to open and close, then watch for the intake to do the same. After the intake opens and closes, you will be coming up on TDC of the compression stroke for that cylinder. Start watching the index mark on the rotor and stop when it aligns with the "T" mark.

 

[TeeCat]

hi, twins...

Yes, I have been doing exactly as you suggest, which pretty much mirrors the method documented at 650central, and here. I was doing one cyl at a time, of course, starting on the left because of the reasons you mention. I went around a lot of times and looked at the clearances on both cyls to get the feel of it.

I think I got them. I set the left cyl when there was just the tiniest free play in both its tappets, and the exhaust valve of the opposite (right) cyl was depressed by its tappet. The intake was at .003 with slight drag, so I left it alone. The left exhaust was a bit tight - it accommodated the .006 quite snugly - so I adjusted it. Now it accommodates an .006 with light drag. I used the "go/no go" method of checking it with a .007, and you can fit it in, but you have to push it, and the .007 is really tight.

I locked it down with that setting and went to the right side, repeating. The intake felt pretty good with the .003, but the exhaust was even tighter than the left, so I adjusted it to the same specs as the left. .006 was smooth drag, and .007 you'd have to push and it was really tight.

I'll roll the motor around and check both sides before I button it up, but that's what I have now. I'm hoping that I have relieved a bit of the stress on the bike because the exhaust valves seemed tight.

I hope everything is okay in terms of valves now. I'll still waiting for my jets. Might be able to move on to finishing my air filter in the mean time, but I hope they come today!

Thanks, twins!

TC

 

[yamaman]

Cool TC, sounds like you've got it sussed!

12 Months ago LOL

20 months ago

 

[TeeCat]

I hope so, yama! Been a long time working up to this, as you so astutely point out!

Guess I'll button the covers up tomorrow and finish the air cleaner setup for the single carb. Still no needle/needle jet today.

Also gonna take my little quarter-liter Ninja out tomorrow for a spin. Not fair to her not to ride her more.

 

[CDNTX650]

easy hey? wait till you get a bike with Shim under bucket or egads.....DESMODROMICS....Even i'm not brave enough yet to do my ducati.

 

[TeeCat]

Well, the procedure itself seems pretty straightforward as long as it works out okay. But I can definitely say that the exhaust valves seemed tight. I just need to build more confidence.

At least there were no unpleasant surprises with this. My time with this bike is generally divided like this: about 60% cleaning up the Previous Moron's mess so that I can do the 40% of what I need/want to do.

TC

 

[XSLeo]

When I do my valves, I do like 5twins said as well as pulling the plugs, the engine turns easier that way, I put a finger over the plug hole as I turn the engine. When you feel and hear air around your finger then you know that cylinder is coming up on compression.
Once you get the pistons coming up on compression watch your timing marks. When they line up at TDC your ok. it may not stay right on TDC. it's close enough for the valve adjustment.
Set the valves on that side. Now watch your timing marks. Turn the engine over till the marks are at TDC again, then adjust the other side.
A bit of drag on the feeler gauge is about right. You can push a thicker feeler in the gap but it can push the valve open. Watching for this is a good idea.
You can adjust the valves with out a special wrench for the little square end. I break the lock nut loose and use my fingers to adjust the screw, then snug the locknut down while I slide the feeler gauge in a the gap. If it tightens up to much as I snug the nut down I loosen the nut and adjust the screw a bit looser then resnug the nut. With a bit of practice you can set them right with just the wrench that fits the lock nut.
You also mentioned a go-no go type thing, for the .003 you can use a .002 and a .004 side by side and use them as a go-no go. the .002 should fit with no resistance and the .004 shouldn't fit. I had a set of feeler gauges set up like that once. The tip of the blade was the .002 then it stepped up to the .004. This was for the .003 gap. Wish I still had them.

 

[TeeCat]

Leo, thanks for these good tips!

I was able to find a tiny little adjustable wrench that I used for the adjuster. To some extent I could turn them with my fingers, though.

I had this done before you guys suggested actually looking at the timing marks (I had thought about that but wasn't sure I could rely on it), but I found that the "window" where both valves on the compression stroke cylinder had a little bit of play was quite "defined" and I could find it reliably.

Two things are certain: my exhaust valves were tight, and now I think they're within spec.

TC

 

[pumps]

@ yamaman Way to go TC! I kinda miss my little Ninjette!

 

[arcticXS]

easy hey? wait till you get a bike with Shim under bucket or egads.....DESMODROMICS....Even i'm not brave enough yet to do my ducati.

2 -valve Ducatis are dead easy, only tools needed are the following. A normal feeler gauge set, 0.05 mm increments, a second feeler gauge in 0.01 mm increments, a 0-25 mm micrometer, and a set of pointy pliers. I can check all 4 valves/ 8 clearances on my -95 Monster within half an hour, and since the desmo/ shim setup is very stable, the actual need for adjustment is rare, perhaps every 20 000 km/ 12500 miles. If it was possible to convert the XS to desmo valve actuation, I would not hesitate

A Jap four with shim under buckets is much more work, especially 5 valve Yamahas......And if the clearance is actually zero/ negative, it requires removing the camshafts TWICE!!!

 

[jd750ace]

When I do my valves, I do like 5twins said as well as pulling the plugs, the engine turns easier that way, I put a finger over the plug hole as I turn the engine. When you feel and hear air around your finger then you know that cylinder is coming up on compression.
Once you get the pistons coming up on compression watch your timing marks. When they line up at TDC your ok. it may not stay right on TDC. it's close enough for the valve adjustment.
Set the valves on that side. Now watch your timing marks. Turn the engine over till the marks are at TDC again, then adjust the other side.
A bit of drag on the feeler gauge is about right. You can push a thicker feeler in the gap but it can push the valve open. Watching for this is a good idea.
You can adjust the valves with out a special wrench for the little square end. I break the lock nut loose and use my fingers to adjust the screw, then snug the locknut down while I slide the feeler gauge in a the gap. If it tightens up to much as I snug the nut down I loosen the nut and adjust the screw a bit looser then resnug the nut. With a bit of practice you can set them right with just the wrench that fits the lock nut.
You also mentioned a go-no go type thing, for the .003 you can use a .002 and a .004 side by side and use them as a go-no go. the .002 should fit with no resistance and the .004 shouldn't fit. I had a set of feeler gauges set up like that once. The tip of the blade was the .002 then it stepped up to the .004. This was for the .003 gap. Wish I still had them.

Good stuff all the way. Many people obsess too much on staying on the TDC mark. A few degrees either way is not a deal breaker. It is much easier with both plugs out for sure. The go-no go gauges can still be had. I have a set, and a set of these:

http://www.bikebandit.com/motion-pr...campaign=pla&gclid=CL27q42A87gCFZSi4AodFh8A9w

I've had them for several years, but the damn things are in Texas, and I'm in Maine (hopefully not for much longer) so I just take the time as stated above to get them right.

 

[Maurice]

What is this deal of having trouble lining up with the TDC mark? I just did the valves and did not find it that hard, if you turn the motor slowly before reaching the mark it eventually stops wanting to turn further.

PO had the valves way too tight on exhaust so I replaced the screws (one was pitted; tip of the valve still looked good) and I got the allen ones. Makes adjusting fairly easy, highly recommend.

I have to say the motor sounds much better after a good adjustment. Before it's almost as if the PO had the clearances backward: tight on exhaust and loose on intake...