TOPIC:

Hiyall,

I just bought a ZN1100 B1 (1984 LTD) and drove around on it for a while as I got it without the airbox and stock mufflers with the dampers out. The carbs were overflowing and it didn't like to start up real quick, but did most of the time after a couple of minutes. I wanted it to perform better so put the dampers back in, put the airbox back on and replaced the o rings on the brass couplings that the floater pins go into. This was causing the carbs to flood as even when the floaters came up and shut the flow of gas as it flowed right passed the o rings. Cleaned carbs and blew out all passageways.

So I figure I must be good to go now right? Wrong! Won't start at all now unless I take the airbox off. Won't idle at all. As long as I keep the revs up I'm OK but as soon as I let go of the throttle it tapers off and stalls. Once it stops it won't start again unless I let it sit for a half an hour or so. Plugs are black which means to rich but when I do the floater test with the hose the gas only comes up halfway on the floater bowl. Floaters are adjusted to 18.6 and I have 122.5 mainjets on 1 and 4, 127,5 on 2 and 3. All is stock as far as I can see from the manual. Pilot screws 2 turns out. Did I mention they've been apart, cleaned and blown with compressed air? The carbs are BS34 mikunis and the jet needle is in the 3rd groove.

I am now officially at my wits end as I can't figure out what exactly the problem is or how to fix it. I'm thinking pilot screw adjustment or clogging... but I don't get the failed floater test (which would mean lean) or black plugs...

All contributions are welcome and sorely appreciated.. thanks!

hopalong wrote:

I am now officially at my wits end as I can't figure out what exactly the problem is or how to fix it.

Here ya go, Hopalong, wear this proudly. Somebody here will bail you out, just not me.
Any chance your last name is Cassidy?

Hey Nevco48... I can't your/my medallion! Yup that's me... and as a matter of fact, my nickname is: Cassidy.

Well waddaya know!

Post edited by: hopalong, at: 2006/09/19 17:49

Post edited by: hopalong, at: 2006/09/19 17:54

Yeah, me too. Got called "Butch" alot when that movie came out.

Hey Mechanical Guys- have a coffee and give Hopalong a hand here?

Hi Nevco,

Looks like schools out!

Do you know anything about how to perform a proper fuel service test? You take a piece of hose and hook it up to the bottom of your carb bowl, then open the drain plug a couple of turns. If your floater is properly adjusted it should come up to just under the carb body. I got my floaters adjusted to spec (18.6 mm) but gas dos'nt even come close to the carb body... any idea?

To perform a service fuel level check/adjustment (I have repeated this many times in the past and a search will turn my explanations up as well as many others):

1. set carburetors level
2. turn on fuel tap
3. connect hose to drain on bowl
4. hold hose next to outside carb on the side you are working on
5. open drain screw - when gas begins to fill the hose DO NOT MOVE HOSE but tap the hose or gently blow into the end to dislodge the air pocket that almost always forms and doesn't allow gas to fill the hose.
6. note the level of the gas in the hose. The gas should be 5mm or just over 1/8" below the gasket mating line. If it is correct, repeat for other carbs. If it is lower or higher than specified, turn off the gas to the carbs and drain the bowl into a suitable container.
7. Remove screws on bowls.
8. Bend down and look at the float. In its center is a square piece of metal called a tang. If the gas level was too HIGH in the bowl, bend the tang UP and if it was too low, bend the tang DOWN. Only a SMALL amount of bending is generally needed. Don't bend the other metal section of the float as the float will lose its referance and make subsequent adjustments in the future all that more difficult.

TIP! The main reason you may not be getting sufficient gas into the bowls is that your vent lines may be obstructed or kinked. Also, air will lodge in the bowl near the drain screw and the bowl won't fill till you clear it as already noted. The float height mesurement that you have been doing isn't particularly effective since the floats already have likely lost their reference.

Allrighty George. This is one mighty valuable piece of information. Thanks... Will let you know how I do.