Think I found the prob w/ my bike.. valve clearance

[richard]

Acting on suggestions from previous posts, I think I may have found the cause of all the problems I've been asking about.

The main problems I've been having are loss of power, poor gas mileage, high idle, and the bike just generally feeling like riding a sick horse (albeit one that can still run pretty fast *most* of the time).  I also have had it occasionally just start dying when I still have gas, but that might be another problem.

I checked the valve clearances today by using (I think it was) JohNLA's method of getting a 2.15mm shim and putting it in, measuring from that to find what size I need to put in.

Here are my findings on the 4 valves, in no particular order, with the old size and the new size:

2.65 -> 2.55
2.65 -> 2.55
2.60 -> 2.55
2.65 -> 2.40

Anyone else think this might present a problem? =]

My question is, have I caused any other problems to my bike with having the valves that far off?  I've noticed the bike has been running *really* hot recently, and yesterday it backfired a couple of times on the freeway, so it just acts generally weird.  Will my problems all go away when I get new shims (Wednesday) and install them?

Also, is there anything wrong with my bike that would have caused this, or is this just the result of it being quite possibly the first time the valves have been checked, and 15k miles on the bike?

[The Buddha]

Ok A box of donuts says the valve clearances aren't that far off...
Why... with them that far off it wont run at all... misfire into the carbs and pop off the vacuum caps and even the carbs off, and in general not run. You have oil float. I'd not drop down more than 1 size shim at a time in any case, and then run it a few mins, split it open and check the clearances. Repeat if needed... though I doubt it will. That 2.15 method will work if you have a dry motor, like after a rebuild. Or I'll send you a smaller dia shim, like 2-3mm smaller. Those will let oil out and not float like the stock.
Cool.
Srinath.

[richard]

Can't get shims w/out ordering them.

How do you suggest I go about checking better?  Just find a smaller shim?  I've got to figure this thing out.  is really irritating.

[Bob Broussard]

The first step is to measure the clearence you have (in MM).
Then pull the shim and measure the thickness I.E. 2.65mm
Then you can email me the clearence for each valve and the shim thickness.
I will check the chart in the factory service manual and tell you what size shim you need.
Or I can scan the chart and email it to you.
I have a bunch of shims, so I might even have what you need.

[Kerry]

How do you suggest I go about checking better?  Just find a smaller shim?

I'd suggest you take Srinath up on his offer to send you a smaller diameter (not thickness) shim.  That would remove some of the guesswork about whether the "test shim" you're using is floating on a thin layer of oil and throwing off the clearance measurement.

Otherwise, we could try sanding the test shim you already have down to a smaller diameter on my Shopsmith or oscillating spindle sander.  Just a thought....

[Kerry]

The first step is to measure the clearence you have (in MM).
Then pull the shim and measure the thickness I.E. 2.65mm
Then you can email me the clearence for each valve and the shim thickness.
I will check the chart in the factory service manual and tell you what size shim you need.
Or I can scan the chart and email it to you.
I have a bunch of shims, so I might even have what you need.

I think Richard has all of the info he needs:

* Haynes manual with this

Shim Selection Chart
* Feeler blades with measured thicknesses
* Conversion factor from inches to mm[/list:u]He (we) followed the steps you describe - we were just surprised at how tight some of the clearances were, and wondered if we measured right.  If the new shims turn out to be too loose, I'll make sure he contacts you with the sizes he REALLY needs.

(Thanks for the shim offer.  Whether or not Richard ends up needing different shims, I may contact you the next time I check my valves.  I don't expect them to be free, but if they're cheaper than the $11-$12 they charge around here, I'm all over it!)

EDIT: Changed link from sisna.com to bbburma.net.

[The Buddha]

OK shim trading... Its free... just postage... unfortunately my gs needs shim changes are random intervals... if they start clacking from the usual ticking... I changes them... but thinner shims areuseless to me... so I can send you a few. Not like they doing anything lying around in the floor of my garage.
Cool.
Srinath.

[richard]

Well, Srinath, I think maybe you owe Kerry and I a box of doughnuts... =]

we used Kerry's 8" sanding wheel (he'll probably post pictures tomorrow) to grind down the diameter of my test shim.  Then we sanded off the slight edge that created, going progressively finer grit paper 'til polished.

measured with that shim.

Other than the first we tried (right intake) which now only seems to need to drop from 2.65 -> 2.60 instead of 2.55, the rest are all the same.

no wonder my bike has been running so poorly!!

if you haven't already mailed them, don't worry about mailing those shims.  we're good.  I think I can pick up the new ones tomorrow and start putting the bike back together tomorrow night, unless you have another concern with this measurement?  don't want to brake anything, etc, just want to be able to ride again.

we ground about 1/5 inch off of the diameter, so there was plenty of room for the oil to move to so it wouldn't float.

[Kerry]

Richard, a couple of nit-picky items:

1) The valve with the not-quite-right clearance measurement was the LEFT intake.  
2) It's a 12-inch sanding wheel.    

Otherwise, Richard's right -- the left exhaust valve was off by 5 shim sizes!  Uh, what are the chances of the valve burning with it being that tight?

Here are selected pictures from tonight's "adventure".

========================================
SANDING DOWN THE TEST SHIM TO A SMALLER DIAMETER
========================================
Kerry "at the wheel"

The shim against the sanding wheel

Richard "at the wheel"

Close-up of the sparks!

Getting a rough idea of our progress using my CHEAP plastic woodworking calipers


=================================================
UNPLEASANT SIGHT UPON REMEASURING WITH THE "SHRUNKEN SHIM"
=================================================
Does the wear on the inside edge of this cam lobe look bad?


I'll probably have to retake that last pic in the daylight.  We were working under a bright worklight on Richard's garage around 11:00 at night....

Anyway, the edge of the lobe looks kinda "chipped" or "crumbled".  Not pretty - but it shouldn't be touching anything, right?

EDIT: Changed links from sisna.com to bbburma.net.

[The Buddha]

OK my 89 has a lovely little crow foot mark on the right intake cam... on the middle part... not edge. The damn thing was there when we first saw it at 10K miles... got it with 8K, pretty sure it was there before. It now has 45K and the crows foot is still visible. Not as deep, but visible. To ~30K I used Mobil1 synthetic... and it never changed. Now that I have regular... its wearing a little. I believe its fine, but it shouldn't be getting worse.
Richard - I will send you the box of dough nuts when you put in the 5 sizes smaller shim and ride it 10 mins and it doesn't clack like crazy, and if it does clack, open it and measure the clearance... and if that is still in spec... then I'll send you $$$ to get the donuts of your choice. Or you want a box of North Carolina's finest... Kripy Kremes...
Cool.
Srinath.

[richard]

It just occurred to me that we do have a picture of what the "modified" shim looked like when inside.



It's slid forward, but you should be able to get a good idea.

I don't really expect you to buy us doughnuts  (unless you really want to)  but I'll let you know how it works.  Something tells me there is a really good chance this will work *much* better than it did.  The one that's dropped 5 sizes I had to loosen the bolts that hold the cams on just to turn the shim to get to the notch to get it out.

[The Buddha]

I buy you donuts... or I'll send you money to cover a box of donuts, Its OK I believe I can afford it... and will help me keep from shooting my mouth off, however I would like to to fit the right shim that your measurements says and ride it for 10 mins, and if it clacks... open it and see what the clearance is in that valve. If no clack... OK fine I'll send you paypal for a box of donuts. What do they cost in UT anyway... we are the headquarters of donuts, with Krispy Kremes factory around the corner. So its good and fresh and cheaper than anywhere else. In fact KK has their own shops like fast food places... funniest thing.
Cool.
Srinath.

[Kerry]

In fact KK has their own shops like fast food places... funniest thing.

We had a KK store go in 2 or 3 years ago, and you're right - it's the funniest thing!  Seemed like that "HOT light" was on non-stop for months and months.  ALWAYS someone in the drive-thru!

I haven't actually visited the store myself, but I do dig their product.  (Folks bring 'em to work, etc.)

Well, if you insist on buying us donuts, we'll be sure to post a picture of us eating them.  Deal?  That will really serve as a deterrent  for ya!

==================

Seriously, thanks for your all of your input Srinath.  You're one of the major reasons that this board ROCKS!

[richard]

<grumbles irritably>

The dealership hasn't gotten the new shims in yet.  They are saying tomorrow, now... which figures, since I don't know if I have time to install them tomorrow night.

Ahh, well.

As soon as I get the new shims, get them installed, I'll let you know how it goes!

[richard]

Well, I installed the new shims.

**WOW**

It's like riding a different bike.  I wonder now if the bike wasn't taken in for it's 600 mile checkup, and the valves haven't been adjusted... *ever*.   This thing has never run this well.

I can accelerate in 6th gear!

I made it to work this morning with 170 miles on the tripometer, and I haven't hit reserve yet.  (I normally hit it at about 140, recently lower)

However, to give Srinath proper credit (and save him from having to paypal me donut money), I have to confess that I can hear a slight clacking sound, seemingly from both sides.

My theory is that two of the shims are 1 size too small.

What problems will this cause?  Should I order the size larger and replace them?

The bike is running better than Kerry's now.  it's astounding.

[The Buddha]

OK 1 shim too small is not a slight clacking... it will be a million monkeys hammering away at your ear drums loud. You actually are fine with the shim size if you only hear slight clacking... so it was 5 sizes off. Well what do you know I was wrong  :dunno: . Valves set properly... or just at the higher side of tight will clack... You are fine IMHO. So I do owe you a box of donuts. Send me a paypal... and yes you do owe us pics of you eating the donuts... and please not any in your underwear while stuffing your mouth full of donut. Send me a paypal ID.
Cool.
Srinath.

[richard]

lol.  that is good to know!  I'm glad I ask, instead of just changing it out!

my paypal id is richardb@byu.edu

we'll keep everything public, eh?  since that's the email listed in my profile, I believe.

We'll post the pics. =]

[Kerry]

I do owe you a box of donuts. [...]  and yes you do owe us pics of you eating the donuts

Here you go, Srinath!

Utah Valve Clearance Checking Party

I bought the KK 2 dozen special (on Richard's behalf) for about $12.  But my wife and I ended up with a full dozen after the party was all over.  Maybe you could send Richard $6 for the box the "Utah Team" gobbled up?

[The Buddha]

I sent him $12 already via paypal... enjoy...
And BTW whose is the eli 125, and why aren't you on elimintor.org.
Cool.
Srinath.

[Kerry]

See my answer to your original question (in the UT - The East Canyon still closed thread).

Sorry - I should probably start a new thread....