Couple problems

So I got my huge order of parts from Chacal today, so I started working on Black Betty. First, replaced the old petcock with an on-off-res type, looks great, chrome, but that will do. That was easy, kinda woke the baby up with the Dremel. No problems there.

So Problem 1:
Replaced the old gasket on the gas cap. Started out bad, took it apart and almost lost one of the many little springs in there. Got the new one on, now I can't close the the cap all the way. Any ideas? Tried redoing it, didn't help. Thought about shimming it a little bit, but don't have anything that would work for that.

Problem 2: Measured valve clearances and only found one that was not in range. Very good, so used the tool to hold down the valve basket, and then could not get the shim out. Tried a screwdriver, didn't work b/c no handy lil slit in my baskets. So guess tomorrow I will get a small neodyne magnet to get that thing out, b/c lost the one I did have.

So far that is all the problems I have had, but I am sure more will come up. Thinking about doing the front brake caliper and master cylinder rebuild tomorrow. Will be stripping the tank to repaint, current paint is really cracked. Will be using the "roller" method with Gloss Black Rustoleum Professional. I will be posting a how to maybe, how I did for that.

Lots of time on my hands... quit my old job b/c I couldn't stand it any more, and waiting on call backs on my million Job applications. Hope the wife doesn't get mad about the money I am spending to keep my self sane by doing lots of work on the bike.

 

Slit is there probably just under the camshaft. The bucket is free floating so just spin it to get to the slit. Magnet will pull the bucket and the shim together but will help spin the bucket. Shim wedges into the bucket so it won't just lift out.

VHT makes a caliper paint in a spray can that will not only go one better than using a brush but will hold up much better. Duplicolor also makes a caliper paint that's just as good.

 

Good Luck to you!

 

To clarify what Blue said: When the cam is off the shim (and without shim too l in place) shim bucket will rotate. Bring the slot into view before depressing the valve and installing the tool.

 

Thank you guys, I had no idea, the manual doesn't say anything about turning the bucket, so I did it, got the one out, it is a 260.
It measured, 0.003in or .76mm, this means that I need a 320 to fix it by the chart. Any one get something else?

 

Oh an to clarify, i am repainting the gas tank, not the caliper. Prob should repaint the master cylinder while I am rebuilding it. You say caliper spray paint for that?

 

Exhaust and intake have different clearances. Which is this?

 

Exhaust

 

320 looks right. I'd measure again though. .76 is very loose, and normally they tighten up over time.

 

"With the shim tool in place".....thanks MiCarl...that was just a littllleeee bit important!

 

Whoa, Nelly! Something's not kosher here.....

.003" clearance is way too TIGHT, not loose, and .003" is not equal to .76mm, that's probably a typo, .003" = .0762mm.

For an '81 650 Maxim, an exhaust valve that currently has a 260 shim installed, AND has a clearance of .076mm would need a........well, the chart doesn't actually go that low, but by extrapolation, you would need a 195 shim, which, unfortunately, doesn't exist! The thinnest available shim is actually a 200, which would give you a clearance of .1362mm, which is still under the specified clearance range of 0.16-0.20mm by an uncomfortable amount.

Houston....we have a problem.

I would suggest re-measuring that clearance, and if it still holds true, then I would suggest measuring that 260 shim with some very accurate calipers to make sure it is actually a 260 size. Unfortunately, valve shims can and do wear---which is part of the whole valve clearance checking process----but this is way off, and either there is an error in measurement, a really worn out or mis-marked shim, or another more severe problem (valve seat recession or a wasted/wiped cam lobe (ouch!) or ????). Does the cam lobe for that valve look burned/blued or brownish in color, any scars or appearance issues?

By the way, you can also try substituting the another shim that you have---even another 260 size shim (if you have one from another bucket, but any other size will do), into this problem bucket and see if the clearance measures the same. That might be a way of doing a quick double-check of the accuracy of the shim thickness.

By the way, Yamaha recommends---much to the chagrin of the "valve shim pool" proponents---that used shims be thrown away, as they do wear down, although the marked size on the bottom doesn't, which then becomes wholly unreliable. Another way would be to measure with some very accurate calipers--or even better yet, a micrometer---what the actual thickness of a given (used) shim is.

Okay, onto the gas tank cap sealing ring. When first installed, they are a little stiff, but shouldn't prevent you from closing the cap. Make sure that the metal base of the sealing ring has slid ALL the way down the cap housing, and make sure the sealing ring isn't installed upside down! As you are holding the cap in your hand---while installing the ring---the sealing ring should be "concave" towards you.

Also, the HCP170 sealing ring only works correctly on the metal-bodied gas tank caps (the metal bodied caps are natural colored metal inside). I've come across a few plastic bodied caps in my time, I don't know what they are off of, but they are definetly the same externally as the standard-issue Yamaha caps and look/fit/function just the same, BUT----the sealing ring on those caps (and the internal locking mechanism, etc.) is completely different, and not interchangable at all, although if I recall correctly, the HCP170 ring will "fit" over the internal latch housing. Just not correctly. These plastic-bodied caps have a black plastic internal housing, really easy to tell apart.

Let us know what you find!

And Happy New Year!!!

 

I'd strip the Paint of the Old caliper and "Brass Wire Brush" it to a nice looking Aluminum.

I even went the next step on mine and Polished the ridges and circles.
Painted the Caliper Mounts Italian Red and now they look GREAT!

I know from what you speak about having the Bike to work-on to maintain your sanity between jobs.

Just have a budget you can afford.
I spent a good couple of months working on mine with just Paint Stripper and Q-Tips.
But, mine was completely Rattle-canned BLACK by a mad-man and all that Black Paint just had to go.

 

Ok, remeasured. little tight on 0.006 smooth on 0.005. Which should that be, I know what happened my .005 and .004 stuck together so they didn't fit so when the next one down. Doh. So that would mean I need a 255... sounds better to me. That is why I asked.

 

The new gasket must be reinstalled in the same orientation as the old one came off or the lid will not compress properly. Look at the orientation of the spring pads.