all day working, now don't start!

[richard]

Well, some of you may remember that I've been having some problems with my bike recently.  I started dismantling it saturday to look for problems.  Removed the tank, removed the airbox, oiled the air filter (when I installed it a couple weeks ago I didn't realize it was an aftermarket that needed oil).

Then I removed the carborators.  One of the air intakes going from the carbs into the engine, the clamp had not been screwed down tight.  I'm thinking this may have caused some of my problems!

Opened the carbs up to look at the needles.  Blew them out, and cleaned some redish gunk from the carbs (thinking rust from the gas tank), and I think I fixed another possible reason, since the wholes in the needles are larger after blowing out than before.

Put the carbs back together, and open the valve cover.  Attempt for about 20 minutes to measure the valve clearances (don't really know what I'm doing) and come to the conclusion that it's smaller than .04mm, but I don't know exactly how small since that's the smallest feeler that Kerry or I have been able to locate.

Put that back together, run to AutoZone and pick up a smallish inline fuel filter.  Install that on the fuel line going from the remote petcock to the carbs, with the arrow pointing towards the carbs.  Reinstall everything, turn the main fuel chicken back on, etc etc etc.  Bike is back together with all hoses (as closely as I can tell) connected back in the correct places.  Vacuum hose I'm not 100% certain I got in the right place, but I'm not certain how I could have gotten it in the wrong place either, so....

The hose on the top of the carbs:  that's just a vent hose, right?  comes out over the air box, doesn't need to go anywhere special?

Check oil.  Add abt 3/4 of a quart of oil.  check oil 5 times consecutively, and then go to the store and get more oil.  Add another 1 1/4 quarts or so.  Vow to never go more than 500 miles w/out checking oil again as long as I live.

Make sure all caps are on tight.  Turn on bike, get set to go.  Hit starter.  Listen to healthy sounding cranking.  Frown when it doesn't start.  Twist throttle to see if any difference.  Play with choke, no difference.  Turn from reserve to prime.

No difference.

Add gas (only had maybe 1/4 gal in there.

repeat all above troubleshooting starting tricks.  no start.

Any ideas?  There are certainly a few things that could have gone wrong with the repair, I'm just not sure which is most likely. I'm thinking I need to check to see if the carb bowls are getting gas, but I had to drive to work today,  so I can't check 'til I get home.  brainstorming in the mean time.

[The Buddha]

OK tank petcock... Is it open... you can actually see it from the right side of the bike... the slot being vertical is open, and horizontal is closed. Esle lower petcock... and floats filling up will be the next choice.
Cool.
Srinath.

[richard]

When I get home I'll double check, but I'm about 99.99% certain it is.  I distinctly remember spending 5 minutes looking for the screwdriver I needed to open it again, finally using one a little shorter and larger than I wanted, and turning it on. =]

I wonder, though...  if I made it vertical inrelation to the bike instead of vertical in relation to the tank, would it restrict the flow too much?

how far off does it need to be before it causes a problem?  Maybe I didn't get it turned far enough, or lined it up to the wrong part of the bike.

[Rema1000]

Try draining the float bowls to see if they have gas in them.  If not, you need to PRIme them for a minute before you try to start (even on RES).

Yes, the top hose from carbs is air-pressure reference hose, don't connect to anything.

On the valves, the procedure in the Haynes manual is not reliable.  The manual wants you to set the engine with the cam-end cutouts facing each other, then check 3 of the 4 valves.  In this position, the left intake cam lobe is pointing straight up, but the right lobes are horizontal, pointing away from each other.  This should imply that there is the same clearance from the shim to the cam through 270 degrees of rotation, with the lobe pointed at 9 o'clock, 12 o'clock and 3 o'clock.  But this is not the case on my bike.  On my bike, there is a little less clearance when the lobes are horizontal (3 and 9 o'clock); and on some valves, there is least clearance at 3 o'clock, while other valves have least clearance at 9 o'clock.

I would try rotating the engine until one lobe points straight up (12 o'clock).  Then check clearance on that lobe, and on the two horizontal lobes.  Then turn the engine until another lobe is straight up, and check that shim, and the two valves that are horizontal.  And repeat.  

If there is insufficient clearance at 3 or 9 o'clock, then that should tell you that the valve may not be opening and closing at the perfect time, but may still be working.  If there is insufficient clearance at all three positions, then you really need to change the shim.  Srinath recommends paying attention to the measurement at 12 o'clock.

GSJack suggests checking for clearance by spinning the whole shim bucket with your thumb instead of using a feeler guage:  if there is any clearance at all, then the whole bucket will turn, and you should be OK.  Testing that way, will allow for tighter tolerances than feeler guages can measure, so I think if you can't turn the shim bucket at any of the 3 closed positions, then you'd want to change shims.

[jake42]

richard,

Double  check the clot on the tank valve.  I did that same damn thing on mine when i had the tank off.
Forgot to open it at first and then hastily pulled the tank up and turned the screw in the dark and tried again.  I knew I screwed up after I opened the drain screw on the carbs with the petcock on prime and still wasn't getting anything in the carbs.  I then took the time, and a flashlight to make sure I had the valve in the correct position.  It you're not getting any fuel to the carbs even on prime this may be your first item to look at.

Jake

[richard]

When I measured, I actually tried several different placements of each one, including directly up at 12 degrees.  My .04mm feeler wouldn't fit under at any point anywhere. :-(

anyone know where small feelers (like the spec .03mm) can be found?

[aslam]

I also went to Autozone and found one which is not metric (has conversions on it) that goes down to 0.028mm so roughly 0.03mm.  That's about all I can tell you on that.  But you're close enough that you can probably swap out shims until you find something between 0.04mm-0.07mm which you can test for.

ASLAM.

[Kerry]

Sorry if I've seemed a bit AWOL.  I've been working my way up through the posts I missed while in transit back to the US, and I've only just arrived at the earliest posts from Monday.

But I "peeked" ahead, saw this thread, and figured I'd better pipe up.

Richard, I'll try to come over and take a look at your hoses and so forth, but it may not be until Thursday.  (Weekly 8:00 PM meeting tonight, taxes still to do ... blah ... blah ... blah.  Sorry!  :dunno: )

Meanwhile, you said you added some gas to the 1/4 gal or so that was in the tank.  How much did you add?  Anything less than a gallon in the tank isn't enough for a good test.  (See?  You should have borrowed the auxiliary fuel tank while you had the chance!  )  But if you do a float height check using the U-tube method and find that you've got full float bowls, you should be good to go.

Did you ever pull the wires off the plugs as you worked on the bike?  Not that you needed to; I'm just wondering if they're pushed on all the way.

Also, you didn't mention whether you had to remove/reinstall the choke and/or throttle cables.  If so, did you get them hooked up OK and is the slack on the throttle cable next-to-nothing?

[richard]

Richard, I'll try to come over and take a look at your hoses and so forth, but it may not be until Thursday.  (Weekly 8:00 PM meeting tonight, taxes still to do ... blah ... blah ... blah.  Sorry!  :dunno: )

Meanwhile, you said you added some gas to the 1/4 gal or so that was in the tank.  How much did you add?  Anything less than a gallon in the tank isn't enough for a good test.  (See?  You should have borrowed the auxiliary fuel tank while you had the chance!  )  But if you do a float height check using the U-tube method and find that you've got full float bowls, you should be good to go.

Did you ever pull the wires off the plugs as you worked on the bike?  Not that you needed to; I'm just wondering if they're pushed on all the way.

Also, you didn't mention whether you had to remove/reinstall the choke and/or throttle cables.  If so, did you get them hooked up OK and is the slack on the throttle cable next-to-nothing?

No worries, Kerry.   I know you're busy.  that's why I'm trying to solve this one (somewhat) by myself for once... if I could just find time to work on it.  I spent the time I might have been working on the bike last night working on the project I mentioned in my Favorite Forum Features post, which I'm doing in preparation for an international PHP contest the weekend after this.

I did pull the wires off the plugs, pulled the plugs (and adjusted the gap on one side), but I made sure I got them back on (I think, anyway, one more thing to check).  The throttle and choke cables are attached and seem to be moving the correct parts as they should.

I think I probably added about a gallon or so.  hard to say.  I'll check the float bowls tonight!  (yeah, I know... you've heard that before.  I got home at 1:30am last night)

[richard]

Alright.  when I turn the drain screws, gas drains in a pretty consistant fashion from the carbs...

when I try to start (it's been on prime for days), it acts like it can "almost" start.... and a little gas gives it an even closer "almost"

I'm wondering if when I put the floats back on the little thingy with the rubber end didn't get on right.  now that I think back, I wasn't 100% certain that it was on correctly.

would that do it?

only other idea I have currently is maybe the main petcock is partially off, not letting quite enough gas through, or the new inline fuel filter isn't letting enough through?

I'm brainstorming.  any ideas?

[Rema1000]

Just to be sure, it's worth trying to start with choke off, then choke on.  Sometimes you think you're way to lean, but actually you're gas-fouling the plugs (but usually you can smell that).

You mention that it seems to start a little better with some gas.  Mine starts better if I choke-on, then blip the throttle 1/4 turn, then wait a couple of seconds, then hit the starter... or at least, it seems that way to me.

I'm wondering if when I put the floats back on the little thingy with the rubber end didn't get on right.

You mean the thing that looks like a stubby pencil (only it's 1cm long)?  That'd be the float needle.   Basically, it works just like a toilet tank.  When the bowl is full, the float rises and pushes the float needle up into the tube, closing it off.  But just like a toilet, if the float or its valve are not installed right, then the bowl just keeps filling and overfilling forever.  If that were happening, and your bike was on PRIme, then you should have a big puddle of gas under the bike by now.  So I think that your float needle is seating.

It's possible that while you had everything apart, you bumped the little metal tabs on the float, making your float level so low that not enough gas is getting sucked up from the bowl.  So check your float level using a short clear tube... it only takes about 30 seconds per side.  If it is way below the top of the bowl, then maybe that's the problem.   Otherwise, the problem is probably somewhere else.  

A really lean condition can be caused by a bad seal between the engine and carbs.  Also, if the choke cable were not working, that could do it.  If you pull down all the way on the choke lever, then go around to the right side of the bike and look up at the other end of the choke cable.  Can you push it in farther?