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Got it! Got the cover off, and of course I don't have a feeler gauge that goes small enough mine only goes to .203 mm and the inlet valve is suppose to be .11mm. Ugh
Question... Now that I've removed the valve cover, do I need to replace the gasket?
Edit: While I was at it, I went ahead and checked the exhaust valve clearance. It's suppose to be set to .21mm and my smallest gauge is .203mm. #1 cylinder - it would slide in at all. #2 and #3, it would slide in. Not freely, but it would slide in. Could this possibly be my issue!? #1 running rich because the exhaust valve isn't opening enough!?
I ran the bike briefly before doing this test and at idle, it was obvious that #2 and 3 were running much better/smoother than #1. #1 was inconsistent and typical symptoms of running rich. I checked the plugs and it was already black after idling for 1-3 minutes.
valves being slightly off spec will not do anything noticable to how it runs,even if they are way outta whack it will only be really noisy or if too tight to the point of leakage well that is an nother issue you only really are doing the clearances becaiuse it is an important service that should be done first rattle outta rhe bag anytime you aquire a used nachine with no knowledge if its service history..that said it is VERY VERY rare to have any valves out of whack very far at all on any jap bike.extremely abused or seriously neglected hi milage bikes are the only time you see it
valves being slightly off spec will not do anything noticable to how it runs,even if they are way outta whack it will only be really noisy or if too tight to the point of leakage well that is an nother issue you only really are doing the clearances becaiuse it is an important service that should be done first rattle outta rhe bag anytime you aquire a used nachine with no knowledge if its service history..that said it is VERY VERY rare to have any valves out of whack very far at all on any jap bike.extremely abused or seriously neglected hi milage bikes are the only time you see it
I can agree with most of the above. Usually one is told to "check the valves" when they are having problems because it's something that is often neglected by each previous owner. One sells the bike before they have to do it, the new guy THINKS the last guy did it and sells it again before the next time, and you buy it missing 2 intervals...haha. Anyways, I HAVE had problems with how a bike ran due to valves before, but 6 of 8 were out of spec. Started much easier and idled more smoothly. I also got better gas mpg. So they DO affect how a bike runs, just not in all cases and bikes. Go tell a dirt rider (with a thumper) that his valve specs won't do anything noticable to how his bike runs and I'm sure you will be the only one saying that The main reason here is that we have SOMETHING going on in cylinder #1. Best to get that valve question out of the way and compression verified (AFTER VALVES HAVE BEEN SET!!)
OH and Treitz! You didn't run the bike just prior to your valve check did you? Bike has to be "stone cold" usually 12+ hours (overnight) before you check.
With the spark plug being black that quickly, I'm still going to have to lean on the carb being the issue here. Unless the black we are seeing is "shiny" in which case that's oil burning...but it would have to be a good amount! (and unlikely to foul that quickly)
Alright, I did run the bike for a few minutes before checking. I admit it. However I checked again this morning after it cooled all night and it was the same results.
Regardless of the running poorly debate, it will make me feel good knowing they are all set. Also curious about checking timing. I don't have a timing light, and I've never done it on a bike with electric ignition. For some reason I thought you didn't have to check timing on a bike with electric ignition, but I guess I'm wrong about that. Anyway, probably not a culprit of the black plug, but worth doing I imagine.
Back to the carbs... Unless there is something that I am completely overlooking, I just don't see anything in that #1 carb that is a red flag. I mean there is the crack that I fixed... but even that little hairline crack I can't imagine would cause the blackening of a plug so quickly. Fuel level has been checked, and double checked. So bizarre.
About ignition timing, on these its set and forget, what can malfunction is the centrifugal advancer behind the timing plate, they corrode and the springs can break. Happened on mine, a little tlc and it was all fine. Just check that it moves through the range correctly without binding.
About ignition timing, on these its set and forget, what can malfunction is the centrifugal advancer behind the timing plate, they corrode and the springs can break. Happened on mine, a little tlc and it was all fine. Just check that it moves through the range correctly without binding.
Take the timing plate off and spin it, or just spin it and make sure it moves smoothly? I was manually spinning it last night while checking the valve gaps and it felt good and smooth.
Then its most probably alright! Would be more concerned about cracked and shorted cables from the timing plate, but then you'd get very difficult starting and misfire thats progressively worse through the rev range.
As for the carb. Let's go through everything in the Beast if you will.
Let's start with the basics.
Verify float needle is the same as the others. Aftermarkets mess with float heights etc.
Check that float needle spring is in good working order and compresses and extends out properly.
Float height (you know it's good/near the others, but check again)
Main jet? Verify by setting near other mains just in case it's been drilled out for some dumb reason?
Main jet holder in correctly?
Missing washer for pilot jet cover?
Pilot jet not drilled out (possible like main jet)
Slide needles all the same (I think you just checked this)
Lastly: The choke circuit. That's the only other thing I can think of. Something is botched in the choke circuit, either not closing fully, or the plunger is stuck or missing? Who knows!?
Verify float needle is the same as the others. Aftermarkets mess with float heights etc. - All 3 float needs are band new.
Check that float needle spring is in good working order and compresses and extends out properly. - Brand new, so shouldn't be an issue.
Float height (you know it's good/near the others, but check again) - Literally JUST checked it like 2 nights ago with a fuel hose connected to the carb.
Main jet? Verify by setting near other mains just in case it's been drilled out for some dumb reason? - Not verified...
Main jet holder in correctly? - Checked when I had the needs pulled the other night. Looked good.
Missing washer for pilot jet cover? - Added these in the other night also.
Pilot jet not drilled out (possible like main jet) - Not verified
Slide needles all the same (I think you just checked this) - Verified
Lastly: The choke circuit. That's the only other thing I can think of. Something is botched in the choke circuit, either not closing fully, or the plunger is stuck or missing? Who knows!? - Checked when I had the caps off, looked ok.
So based on the 2 unverifieds being the main and pilot jet... I wonder if it's worth swapping the main AND pilot from #1 into #2 and seeing if suddenly #2 is rich instead of #1!? Not sure how else I could be sure if it's the jets.
So you pulled each one out and made sure there wasn't anything in there causing them to not seat fully? (just checking, not harping on you) I've had a couple of customer bikes come in with one of the arms BENT which caused a very annoying rich single carb on a rack of 4 in the past. haha. They might have pried up on it trying to get the carbs out or whatever. Either way it held the one choke plunger open ever so slightly enough to have me pull out my hair.
There's one other thing that meters the pilot jet and that's the air jet in the "back" of the carb (your way of saying back...aka the side air comes into the carb)
"So based on the 2 unverifieds being the main and pilot jet... I wonder if it's worth swapping the main AND pilot from #1 into #2 and seeing if suddenly #2 is rich instead of #1!? Not sure how else I could be sure if it's the jets."
^^ Worth at least pulling out and looking through 2 of them if you don't have a little "carb cleaner" tool that has multiple sizes that you could at least guesstimate it. The average pilot jet can ONLY be cleaned by the smallest needle on the tool. If you can use another one...it's been drilled out. Don't ask me again how I know this....ugh. PO's and their tactics some times!
So you pulled each one out and made sure there wasn't anything in there causing them to not seat fully? (just checking, not harping on you) I've had a couple of customer bikes come in with one of the arms BENT which caused a very annoying rich single carb on a rack of 4 in the past. haha. They might have pried up on it trying to get the carbs out or whatever. Either way it held the one choke plunger open ever so slightly enough to have me pull out my hair.
Are you talking about the float needles or choke plunger here? Confused.
I did not pull and check the needles, but like I said, they're brand new. Also, since these carbs do not have an overflow tube, if the float needle wasn't seating, it would be dumping gas out of the air filter. Been there done that with a sinking float on one of these before.
MotorbikeBruno said:
Worth at least pulling out and looking through 2 of them if you don't have a little "carb cleaner" tool that has multiple sizes that you could at least guesstimate it. The average pilot jet can ONLY be cleaned by the smallest needle on the tool. If you can use another one...it's been drilled out. Don't ask me again how I know this....ugh. PO's and their tactics some times!
Yeah, I could pull two of them and try to compare side by side. If no noticeable difference, maybe I'll try the swap. I typically strip a piece of electrical wire and run it through the jets to make sure they're clean and clear.
And I'll check those air jets while I'm at it.
You're right, people do strange things. It just doesn't make sense that only ONE of the jets would have been drilled out or whatever.
Nope I was talking about the CHOKE PLUNGER. Make sure it moves freely and isn't on a bent arm! So it's clear in there and closes off the fuel flow properly!
I find that they tried on ONE carb, effed it up and then stopped due to lack of motivation to screw up the other 2! : ;D ;D ;D ;D ;D ;D
Nope I was talking about the CHOKE PLUNGER. Make sure it moves freely and isn't on a bent arm! So it's clear in there and closes off the fuel flow properly!
I find that they tried on ONE carb, effed it up and then stopped due to lack of motivation to screw up the other 2! : ;D ;D ;D ;D ;D ;D
Right okay... I did slide the choke lever back and forth with the carb caps off and everything appeared to be operational. Open when open, closed when closed. No red flags at least.
I'll start by checking those jets again, including the air jets. Of course in addition to getting my valves adjusted appropriately and checking compression...
Sounds good. What I would do is take a can of carb cleaner. Spray up the straw, and if it just comes out the rear hole, you have a problem. It SHOULD be blocked when the plunger is closed, and open when it's lifted out of the way. Hopefully the attached pictures show the proper spots. I marked up the ones from the guys post.
Provided a range because I didn't have a .01 - .04 gauges. So I measured based on the largest I had that would fit, and the next up that wouldn't fit. Based on these results. It looks like the only one I need to fix is the exhaust valve on cylinder #1. If what XB says is right, this shouldn't be contributing to the rich running, so I might just wait to do it until the winter. You guys agree?
Now back to the carbs... (some important findings here)
I checked the fuel jets again and didn't notice anything different from #1 - #3. But I switched the jets between the two anyway just out of curiosity. Checked the choke system by shooting the carb cleaner through, no issue. Now I don't want to count my chickens before they hatch, but when I pulled the air jet on #1 it appeared to be super gunked up. Not sure how this is possible as the carbs went through a deep cleaning... but regardless, if that jet is pulled, I would be getting very little to NO air through the system at idle. Seems logical that this could have been my issue. Going to throw the valve cover back on tonight and give it a shot!
On a side not, I was wrong about that cracked pilot jet housing. It was actually on carb #3 not #1. So I can rule that out as a cause. I can also hit my forehead with my palm for getting #1 and #3 mixed up. :-[
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mine only goes to .203 mm and the inlet valve is suppose to be .11mm. Ugh
