This Bike hates me - a tale of hateful carburetors.

Alright, so I played with the air screws a wee bit. I got 1.5, 1.5, 1.0, and 2.0. So clearly some genius decided that was what was the good stuff, at some point. This actually neatly agrees with with the temperature gun readings I was getting, which were 438, 438, 452, and 427.
I set them all to 2.5 for now, and once I started the bike I realised that the sync is once again very, very off. I'll be doing that once again, see if I can chase those zeros down and get it running better.

 

I have it synced again, it's sounding a little bit better, I won't know how good the sync really is until I ride it. The 2-3 pairing was the hardest to sync, that's a pretty consistent issue I find, they want to wander a fair bit.

 

When you synch the two pairs (with the synch screw on #2) are you going back and rechecking the relationship within each pair (1 + 2 / 3 + 4)?

 

Yes I do, I know how they can be upset by using other screws. I'd have checked it even more, but then one of the bottles developed an air leak where the hose gets through the metal lid, so I'm going to have to come up with a better way to seal them up.

 

Got any chewing gum? Really. It works in a pinch.

 

Riding the bike to and from work, backing out the air screws definitely had a noticeable effect on how the bike ran. I might push them out a bit further, to 2.75 or to 3 just to see how it runs. the idle and off idle running is much smoother, with only the slightest hint of hang up, but that could just be me needing to work on my clutch transitions. Above 3.5 to 4k it does vibrate a bit, perhaps a bit more than before I played with the air screws, so I might need to do more work synching it when I seal up the bottle manometer.

 

Does the vibration smooth-out after 5k? The 4k vibe is a persnickety little devil. Hard to get rid of entirely. It's the resonant-frequency of the whole bike making itself known.

 

It smooths out at maybe 5.5 to 6k. I think it's the usual vibration I'm dealing with, I'm hoping it's just a bit stronger at the moment because the bike isn't synced quite as well as it was before. I'm still working on that.

 

That is more than likely what's going on.

 

Found this online maybe it can help. It tells you what jet or fuel circuit the carb is using in relation of throttle position.

 

the fix for the vibration you feel at mid-range is to ride a one or two cylinder bike for about a hour. or a HD for 10 minutes.
the sync isn't really going to change much in the mid-range. the tiny amount you move the butterfly to sync at idle doesn't matter when the butterfly is opened up.
it's a math problem that makes my head hurt

 

They aren't air screws, they're fuel screws- opening them up richens the mixture. Glad that seemed to help, and with a bit more sync'ing, you'll be golden!

 

I definitely agree about the harleys, I'm working with the neighbor fixing his up and it's pretty nuts seeing how much the front wheel is bouncing about, even when he's sitting on it. I guess it's something you get used to, though with this bike I know it's run a little smoother than this before from experience, so I'm going to keep fighting.
I have to disassemble the bike again, going to be doing that tomorrow. I must have not read the part that mentioned that pulling the carbs off of the rack would definitely without a doubt destroy the fuel rail o-rings, so I'm replacing those since I'm leaking fuel. I'm also replacing the valve cover gasket because the one on the bike, despite being pretty new, is splitting in a most unusual way due to some kind of manufacturing defect, so that's going too so I'm leaking oil. I've also got new vacuum caps since one of my old ones was lost and the autozone ones are laughable. THEN I'm going to turn out the air screws to maybe 3 or 3.25 to see how it likes that, and THEN I'm going to be synching it again since breaking the rack will probably upset the sync a bit though I want to see if I can break and unbreak without actually backing out the sync screws this time, prevent a fair bit of hassle. Also, throttle cable.
No half measures, my bike might LOOK like it was backed over with a truck, but if will run as if it wasn't backed over. If I can do that, I'll say my job is done. For now.
Goodness knows there's always something else to do on these, but it is a passion.

 

There is always something else to do to any machine. By going through things as thoroughly as you have been, you will maximize the time before the next thing needs doing.

 

This is the exact set I have (carb vac gauges):

http://www.ebay.com/itm/Motorcycle-...ash=item4ae688a45f:g:iYkAAOSwKfVXK~U~&vxp=mtr

Pretty reasonably priced, work just fine, and much better than whatever contraption involves bottles with holes in the lid. I am all about making do with what is on hand, however if you are relying on this machine for transportation, this tool will be money well spent on making it run as best as possible. And if after one use you decide you don't want to hang on to it, you could easily re-sell it and get 75% of your cash back.

Some more options:

https://www.amazon.com/s/ref=nb_sb_ss_c_0_10?url=search-alias=aps&field-keywords=carb+sync+tool&sprefix=carb+sync+tool,aps,132&rh=i:aps,k:carb+sync+tool

For less than $10 more than the link above, you get get one via Prime with 2 day shipping. Thats a deal!

I have spent LOTS of time making do with sub-par tools and equipment. And when I add up all the extra time and frustration that comes with diddling around with stuff like that...well, I don't know about you, but my time is worth something, and the investment in the proper tool will always save time, as well as blood sweat and tears! This is one job that having the proper tool will make it go much more smoothly and with a greater likelihood of being done right the first time.

 

Wrong

 

This is the set up I have...used it on all the bikes I've had and all the Hondas my dad has had. ( he gave them to me his Goldwing does not need them FI) I love using these gauges.

 

Agreed. I've made manometers to work on industrial machinery that are almost as accurate as the certified ones. The only difference being the accuracy of the scale (well, the accuracy of the drawer of the scale), which isn't an issue when balancing two or more vacuum ports.
The upside of store-bought is the time you save in not having to build the thing, and the ease of transporting it.

 

Even when you take into account time spent building, and the cumbersome nature, etc? Just because it works fine, does not mean that a tool made for the job isn't better.

EDIT: ok. So home made manometers technically are a tool made for the job. But I think everyone gets what I'm trying to get across. Personally, with a procedure like this that requires a fair level of precision, I would not want to have any doubts if my equipment was adding to the complexity of the operation. One less variable.

 

precision is the reason to use one that bubbles. if you leave it on for thirty seconds and the water level doesn't change your far closer than a gauge could ever get. actually your way closer than you need to be. the gauge gives a instantaneous readings and the bottles give a cumulative reading over time.

 

That's an interesting insight into why it is that these bottle numbers are seen as being so useful.

That makes a lot of sense, though in the end I think both tools do have their place. That cumulative reading does result in a fair bit of lag in the adjustment, if it's swinging heavily to one side and you're trying to swing it the other way, it's pretty easy to over correct because of how they react. I personally wouldn't mind having both, and with prices like that, I might just end up picking up a set of vacuum gauges, even if it's "for next time".
For todays work, boy was it interesting. The new valve cover gasket went on, and I'm glad it did, the old (only two months) one was SHREDDED. A good three inches of one of the inside flat regions was split up terribly, no wonder I was leaking oil. The new one is from Chacal, I've been happy with everything I've gotten from the shop so far, so I hope this one lasts. The carburetor fuel o-rings went in easier than I'd anticipated, I opted for the viton aftermarket set. Turns out breaking and unbreaking the rack with the sync screws still synced isn't that terrible, which is good information for people to have. Don't screw up your sync if you don't strictly have to do it.
Still leaking some fuel, I think No#2's bowl gasket is leaking. we'll deal with that at some point. I'm not as worried about losing fuel as I am oil. You can get fuel anywhere at any time of day or night, getting motorcycle oil at 3:27am, technically monday morning, isn't something I'm up to do.
Now what was really, really fun is when I was trying to get the spark plug wires out of the way of the valve cover and I tore one of them. It was a sunny, mosquitoey day here in americas northern swamps, but in that garage there were lightning clouds threatening to set off some gas fumes and bury the whole project in rubble, and me with it.
I didn't realise that the spark plug "plug" disconnects from the wire. That it's press-fit. I spent a good half an hour listing about, propped up against a drill press, thinking very dark thoughts.
Boy was it a good feeling when I finally realised that the cone shaped wire thingie goes into the slightly stretched out rubber thingy, and it wasn't in fact broken.
Turned out the Fuel-air screws to 3, liked the result. I'll keep tweaking those, since they are by far the easiest adjustments to make on the bike. Just prop the rear of the tank up with my 3/8 inch socket wrench, and get in there with a suitable flathead.

 

Fuel combusts. It's preferable to have that happen on the inside of the engine.
This happened a few weeks ago.
Fix the leak.

 

You got INSTAGRAM K-MO???

 

Fair enough. I'll see about what needs doing and how it'll get done. Be sure I'm only leaking from the one carburetor, etc.
Definitely an effective way of getting the point across. Reminds me of a video I saw in slow motion of a racer on a blue and yellow "WD-40" sponsored bike, you see the moment when he looks down and sees flames beginning to come up from the FRONT of the gas tank, you see him rise off the seat just like so as he promptly pulls out of the turn, onto the grass, and off of the bike.

 

nope.