Still only runs on 2

[Alan H]

Maybe it's a Monday morning or Friday afternoon carb originally built by someone hung over or ready for the weekend.
Remember that this is a 40+ year old carb that may be from another bike anyway. If there is a slight difference in air passage on that one, then the mixture screw adjustment may be the way to get it back in spec.
Just a thought, are all the slides the same number? If one has a different cutaway, that might affect the bottom end.

Adjust it so it runs right, if it's different to the others, so what? Just check the plugs for colour when it's on the road and make sure the mixture is ok on the plug colour.
If your wife was one of three sisters, she might need some tweaking to get the best out of her too - you know what I mean, I'm sure!

[rngdng]

I clean the bypass ports with a small guitar string, followed by canned carb cleaner.


Lane

[Coyote]

There won't be any updates on this thread for a while. I ordered new intake boots this morning and I need to wait for those before I proceed. You never know with Partzilla. Could be a week, could be 2 weeks+. Normally it's around 10 days if they have the parts in stock. The fiches are still blank so I got the PN from AlphaSports.. Huge difference in price. AlphaSports gets $21.44 each. Partzilla gets $14.47. I have never ordered anything from AlphaSports so I don't know what they charge for shipping. With Partzilla it's $5.95 for standard or $8.95 for expedited. I chose standard.
In the mean time I'll see what's up with the center carb. I'm hoping to find a loose pilot jet --- but that would be too easy.

[ConnerVT]

If your wife was one of three sisters, she might need some tweaking to get the best out of her too - you know what I mean, I'm sure!

Maybe a side-by-side comparison is in order?

[Coyote]

Well, maybe there will be more posts This is just the starter pipe right? (photo) Holes in it were partially blocked. Pilot outlet and bypass are open and flowing good. I think the jet had a fleck of something in it. Could hardly blow through it.(mouth pressure). I cleaned it with a .018 wire and it is definitely more open.
So I'm trying to understand the function here. The little cross holes in the pilot jet waist I assume feed the bypass. Is that right? then the main hole goes directly through to the venturi?
Spraying cleaner in the bottom of the pilot hole flows freely through the main and bypass holes. The only other thing I found in there was one of my hairs. Oh, and float level was slightly low

[bill in okc]

Make sure the well in the float bowl is not clogged with sediment. I had one that was still clogged after an ultra sonic cleaning. That small angled opening at the bottom likes to collect dirt and it turns to cement where you can't see it.

[yeadon_m]

Those cross-drillings in what I term the choke straw are critical in mixing air with fuel in the cold start well. Even if the straw itself is clear, you also need to check carb spray emits symmetrically from the holes. In different carb sets, the number, location and diameter of the cross drillings differ. I guess Mikuni played with those for quite a while to get them as close to correct as is possible in such a primitive system. The cold start system is a stand-alone carb-within-a-carb, an intriguing thing!
Good luck,
Mike

[Vintageman]

Is issue only when idling? Open throttle the non firing cyclinder fires OK?

[Coyote]

I think so. I didn't really run it long enough to see. Pipe got warm, the other 2 got hot. Now I am in limbo waiting for new intake boots. Did find ALL the float levels a little low and corrected that this morning. Also did the drain through the pilot cavity with the jets in place. All flow at a similar rate.. I'm really anxious to try it again.

[Coyote]

CRAP! Double CRAP. I just got the most dreaded email from Partzilla. "You have one or more items that have been delayed". So much for getting the boots in a week I've been down this road before with them when I was ordering lots of parts. What this means is "we don't have those on hand, but we will ship them when we do" Usually this takes an additional week. All I ordered this time is the boots.
Not sure but I think these boots were obsolete for a while. I hope these are from a recent run and not 38 year old new ones. The boots I have are not all that bad. All are crack free, but all are rock hard. It takes a lot of heat ti get these pliable enough to install.

[bpeck27]

Coyote:

This sounds like the same problem I had with my 550 not idling, except yours is only doing it on the center hole. My problem was with the float levels. At the spec height of 1" there was enough fuel in the bowl for the main to pick it up, but not the pilot. It idled OK with the choke on, but with it off the engine gradually lost RPM until it died. I now have my floats set at 27/32" and the bike runs (and idles) great. Also there is no sign of overflow from the bowls.

I suggest you try raising the center float to, say 15/16" and see what happens. The worst that could happen is you leak a little fuel out the overflow.

[Coyote]

New boots DID ship yesterday. I guess they just ran out of time Friday. I'm not crazy about the shipment method though. I don't know what UPS calls it, but FedEx calls it smart post. What that means it is handled by 2 different carriers. In this case UPS and USPS. That translates to SLOW!. Expected delivery is Friday 9/18. . Somehow those split shipments are cheaper for the shipper. Not so hot for the customer. 5 days from Alabama? Normal FedEx or UPS would be 3 days. At any rate, I should have it running again this weekend. Watch it rain.
bpeck27, I raised the floats a little, but not that much. Just have to see what happens.

[Coyote]

Boots schedule arrival update.. The internet says today. A day early!. As my luck usually goes, I threw my back out first thin this morning. Got up, took a leak, picked up my back scratcher., used it. Fine at this point. Went to set the back scratcher down and my beck went in 13 different directions. Currently can't hardly walk. Back scratcher weighs all of 3.oz. It was the way I moved I guess. You guys that have been there know there's not much to do other than tough it out. Heat pad will sooth it but doesn't cure anything.

[Suzukidave]

I am with ya , i have hurt my back so bad i couldnt stand up and it was from doing the most simple things .

[Alan H]

Boots schedule arrival update.. The internet says today. A day early!. As my luck usually goes, I threw my back out first thin this morning. Got up, took a leak, picked up my back scratcher., used it. Fine at this point. Went to set the back scratcher down and my beck went in 13 different directions. Currently can't hardly walk. Back scratcher weighs all of 3.oz. It was the way I moved I guess. You guys that have been there know there's not much to do other than tough it out. Heat pad will sooth it but doesn't cure anything.

You could have damaged you back when lifting heavy weights while having a pee!
Take more care in future!!!