post carb cleaning, trouble

[XSLeo]

Yes, the thickness is the thing. If I recall right the grooves are about 1 mm apart. Get washers about .5 mm thick. .25 mm even better. Thinner means you can adjust in smaller increments.
A soda can and a set of hole punches to make your own will work too.
Leo

 

[5twins]

Yes, Mikuni needle clip slots are 1mm apart. Moving the clip changes the needle height by 1mm. The 1/2mm washers are what you want. I found anything less really doesn't do much but a 1/2mm change will.

 

[emzdogz]

Looks like I went too far with adjusting floats in order to not have the "rich-running at idle" condition. (just to re-cap, it was so rich that the right side cyl's plug would gas-foul and not run hardly at all, leaving that side "cold")

Adjusted plastic floats to 23mm.... thus hoping to have them positioned for leaner running. I also put in one size smaller than stock pilot jets. Also went through carbs again with carb spray, although I didn't do a full dis-assembly.

Put carbs back on and it just cranked and cranked and cranked and wouldn't start up at all, choke or no choke. Previously it had been rich enough to start from cold with no choke at all.
Had spark. Had at least some gas in bowls.

Finally I sprayed starter fluid into the carbs and it did start up, but just for a few seconds.

So, carbs will come back off tomorrow.
I guess it would be best to only do one thing at a time.
Thinking I can change the pilot jet with carbs still "in" bike but not stuck in intake boots. i.e. take them out of boots and with them loose, I can remove bowls, rubber plugs and swap the old pilots back in.
So at that point I will have LEFT the floats at 23, but gone back to stock pilot jet.
I'm really curious what that might do.

My guess is maybe it will start a little better but run real lean and I will have to mess with floats yet again.

So throughout this whole trip, it's gone from being able to start from cold with no choke and running super-rich, to not starting or running at all except WITH choke and with starter fluid sprayed in.

Just wondering how much difference one size on the pilot jet can make. hmmm

Back at it sometime this week, as time allows. If I have to take the carbs off and out again to do floats, I won't put them back on without doing the level test with tubing.

 

[5twins]

You can change pilots with the carbs still mounted. Use a stubby screwdriver to drop the bowls. My "weapon of choice" for installing/removing jets and bowl screws are these Craftsman knurled bit holders .....

They allow you to install the screws/jets tight enough but not too tight so they can be removed easily. Used in conjunction with the proper sized metric flat blade, J.I.S. Phillips, or metric Allen inserts, it does a wonderful job.

One size smaller pilot shouldn't make the bike not start but that float level setting just might. I'm thinking either you didn't have the floats set correctly @ 22 before (even though you thought you did) or maybe if your other pilots were the originals, they could be worn bigger than stock. They don't really "wear" through use but if the carbs were badly gummed up at one time, that gas residue can eat away the inside of jets making them larger (richer).

 

[emzdogz]

Nice tools! thx...Ps: didn't see the second part of your post til now. Thx again...

 

[emzdogz]

Have had the carbs back off and on several more times trying to tweak the float height. Also put old pilot jets back in. I believe I now have the floats set at 21mm. (plastic ones)

Turned on petcock and pretty soon (as bowls filled) gas starts gushing from a place I've never seen it gush before - from 2 AIR jets. I always thought when the carbs overflowed it came out of the hole at bottom of throat of carbs where the slide needle pokes in. And maybe some came out of there, too. But it was just GUSHING out of these 2 holes.

Any ideas for me? please click pic..... (I think next I'm just going to put the old brass floats back on, dent or no dent and maybe even the old float needles, too)

thanks, in advance.

 

[5twins]

Those air jets lead to the pilot and needle jet areas. If the fuel level in the bowls raises high enough then yes, fuel will overflow out those jets. Yes, I would give the old parts a try. Certainly can't hurt to try them since the new ones obviously don't work, lol. Did you see the recent post about the rubber tip on a MikesXS float needle puffing all up due to ethanol? You might want to compare them to your originals.

 

[emzdogz]

ok thanks for looking. Yes I did see the post about the "bloated" tips. Mine don't look that way.

So, I'll try, try again!
(The one good thing about this is I can now put these carbs off and on in very little time....)

Somebody needs to create a video game based on "beating" a pair of recalcitrant Mikuni CV carbs.

 

[emzdogz]

Put old brass floats on and set to 27mm. Tried to put old needles in too, but i noticed one no longer had any "spring" action to it, where the tang contacts it. It was stuck.

That was probably my problem all along and before I just didn't notice that. To be honest I didn't realize that end was supposed to be "springy" until fairly recently.
So now I've got one old needle and one new one. Still using the new brass seats.

Put carbs back on bike. Didn't overflow! yay!

However it also didn't start except for one (very) brief time. Just cranks and cranks and cranks. Got the battery charging again now - will try again later.

Maybe the floats need to be at 26 instead.

anyway......

 

[5twins]

If the spring loaded needle pin is stuck "in", sometimes you can free it up with some penetrating oil and by "working" it in and out. They get gummed up and stick sometimes. With the brass floats especially, make sure you measure and check from both sides as they can be twisted or tweaked, making one side sit higher or lower than the other.

 

[emzdogz]

Yes these floats are definitely not perfectly straight, but I've tried to gently bend them as "true" as possible. I bought a height checking tool, makes it pretty easy to check both sides.

my vision isn't what it used to be....
thanks again, 5twins

 

[emzdogz]

ok, it started up. Now I'm exactly right back at post #15 of this long thread.

Tried that "other" dead cylinder thing - not the one where you pull a sparkplug but the one where you pull the vacuum barb cover off to "kill" that cylinder. Right cylinder (bad cold running side) does run somewhat by itself, but not consistent like left side. Right side still doesn't respond to manipulating the mixture screw. It will idle higher if I manipulate the carb balance screw. So the right side isn't completely dead.

These carbs btw, still had the seals over the mixture screws when I first started using them. So I don't think that part of the idle circuit was damaged in the past with a wire being stuck in, or anything.

I guess I'll try putting the stock mixture screws back in, instead of these Mike's ones.

If I knew 100% for sure it's a carb issue, I'd just buy a new set of carbs.

ah well, back to the drawing board, another day.

With stock elec ignition is there any point to checking timing with a timing light? I have one. Seems like the right side only combusts every other cycle, although it gets spark every time - I can see that through clear plug caps. So every other pulse even though it gets fuel and air and spark it doesn't do the "bang". It's sucking, but not banging and blowing correctly.

 

[kvanderploeg]

Please, if only for my morbid curiosity, check your timing with that timing light!

Kent

 

[emzdogz]

OK Kent, I will go through valve adjustment one more time "just in case"....and then if nothing changes, just for as you say, "morbid curiosity", I will pull out the timing light.

lol!!!!! and then I can start a new thread!

 

[kvanderploeg]

Thanks, Emz! If it does end up being your TCI box, I'll gladly send you my TCI that I replaced the diodes in. No connector on it, but it did work great before I switched to Pamco.

Kent

 

[emzdogz]

wow, thanks!
let's see how this goes.

 

[emzdogz]

one thing: the metal guard right by the pick-up coil is bent - not sure if I did it while rotating engine with wrench while doing valves, or if that piece has always been bent. Bent as if jammed hard with long wrench while attempting to turn wrench too far counter-clockwise. Maybe it's touching and screwing up the pick-up coil. hmmm

 

[kvanderploeg]

The plot thickens...maybe a pic to see the damage?

Kent

 

[emzdogz]

ok here it is.

 

[5twins]

That's not the pick-up coil, those are your brushes. Just bend it back with a pair of pliers.