Hope you guess my name ( new member, sort of )

[5twins]

No, that's a float or float needle and seat issue. The floats may have gone bad, filling with fuel and becoming "sinks", lol, or the float needles aren't sealing in the seats.

 

[John Regular]

Alrighty then, I got distracted by a crazy red head named Maxine and have been spending a little time getting to know her
She is going to need some work. Back to the carb guide! The next step is pulling the float bowel and removing the floats and

valve. The Guide and pic of a suzuki BS34 state that The BS34 float needle is retained by a screwed-down tab, however mine was not. It came out with the

float


Is this normal for a 1980 BS34? Do I maybe have the wrong seat? Does that needle look ok? I'm going to attempt to unscrew the seat but if it's stuckk I'm

going to wait for the JIS drivers that I ordered to get here. I'l test the floats tonight.

 

[5twins]

The float needle seat is retained by that little screwed down tab, not the float needle. It is as you found yours, and that all looks correct and original. The seat is just a press in fit into the bowl and has an o-ring around it to seal it into the hole. They can often be quite stuck and getting it out can damage it - unless you make up a simple "special tool". This is nothing more than an old shanked bolt with a slight taper ground on the shank end ......

You tap it into the seat and grab it with some vice grips. It allows you to rock the seat back and forth but more importantly, to twist it and break it free .....

And the best part is no damage is done to the seat.

 

[John Regular]

The float needle seat is retained by that little screwed down tab, not the float needle. It is as you found yours, and that all looks correct and original. The seat is just a press in fit into the bowl and has an o-ring around it to seal it into the hole. They can often be quite stuck and getting it out can damage it - unless you make up a simple "special tool". This is nothing more than an old shanked bolt with a slight taper ground on the shank end ......

View attachment 348278

View attachment 348279

You tap it into the seat and grab it with some vice grips. It allows you to rock the seat back and forth but more importantly, to twist it and break it free .....

View attachment 348280

View attachment 348281

View attachment 348282

And the best part is no damage is done to the seat.

Thanks, thsat's what I figured but wanted to be sure. So there is a typo in the guide that might confuse people who don't know any better, like me.
"The BS34 float needle is retained by a screwed-down tab" I tried to take a screen shot but can't find it, Ill try to make one of those special tools

 

[John Regular]

So it took a while to get the chokes unstuck, one is still a little sticky. I decided to make one of those tools to remove the float seat but smoothed it out a little too thin to fit tightly but I found another way, One of the seats just kind of fell out once I removed the keeper. I'm guessing that that's not good? Here's some pics Looks a little dirty to me. Everything else was all shiny and new so I was hoping I wouldn't have to mess with them too much but it will be good practice and I have 2 more sets to rebuild. I need to get a real parts cleaner, I've been using one for gun brass

 

[John Regular]

I decided to get started on the carbs again today . I figure after seeing how gummed up the choke and valve seat were that I would plan on doing a

complete tear down and cleaning Following the guide. With all the tips and tricks and little caveats of info it's nearly idiot proof. Nearly. I don't mean to

criticize the guide but myself and how I often miss the obvious. I was trying to remove the needle jet per the instructions. I knew you smack it out (gently)

from the bowl side through the venturi. I installed the main jet back on and found a piece of ABS plastic to make a drift punch out of and gently beat the

shit out of that circuit for hours. I only got it to move a coup;e of milometers. I tried heat, penetrating oil, prayer, nothing would budge it. I knew I had to be missing

something so went back to the search looking for an answer and every post seemed to mirror the guide instructions, Install the main jet hit it out from the

bottom and it will eventually come out. Then I found the phrasing that I needed with a little extra nugget of info. To remove the needle jet First remove the

slide assembly, the main jet then REMOVE THE WASHER that is under the main jet, re-install the main jet and gently TAP out the needle jet. Thanks Twins.

I learned that the washer, which is also brass and looks like part of the needle valve especially after hammering on it and fusing it together with said valve,

actually holds the needle valve in the carb body. Well I still managed to move it a little so how bad did I f@ck it up?

 

[5twins]

I think you'll be OK. If you deformed the washer from beating on it, "dished" it in towards the needle jet then I would recommend flipping it over when you reinstall it so the needle jet will get pulled in completely and seat into the carb body all the way.

Good thing you got it out, it looks nasty, lol. My buddy swore up and down to me that he cleaned and/or replaced all the parts in his BS34s. When I finally had a look at them, they were a mess, lol. He never pulled the needle jets out and they were even more gummed up than yours. And he had plastic floats set at the brass float spec.

Make sure you clean out all the little holes down the sides of the needle jets. Those are the air bleed holes and if plugged, there won't be enough air let in to mix with the fuel, resulting in rich running.

 

[John Regular]

I think you'll be OK. If you deformed the washer from beating on it, "dished" it in towards the needle jet then I would recommend flipping it over when you reinstall it so the needle jet will get pulled in completely and seat into the carb body all the way.

Good thing you got it out, it looks nasty, lol. My buddy swore up and down to me that he cleaned and/or replaced all the parts in his BS34s. When I finally had a look at them, they were a mess, lol. He never pulled the needle jets out and they were even more gummed up than yours. And he had plastic floats set at the brass float spec.

Make sure you clean out all the little holes down the sides of the needle jets. Those are the air bleed holes and if plugged, there won't be enough air let in to mix with the fuel, resulting in rich running.

I thought maybe I malformed the top of the needle jet and I did slightly mushroom the top of the main jet but I don't think it will effect anything. The rest of the carbs looked really clean and had new bits put in (from PO) I have another pair that He Cerakoted (the carb bodies) with new jets and pieces. I have another pair on a spare motor I picked up so 6 in total, I figure if I rebuild all of them then I should have a better understanding of Bs34s.

 

[5twins]

Even though many prefer the BS38s, the BS34 is a nice carb. It's lighter and more modern that the BS38, and once you "fix" the factory lean jetting, they're a really good carb. Speaking of which, even an all stock bike will be happier and run a little nicer if you go up one size on the mains (132.5 stock to a 135). The bs34 also has a removable air jet feeding the idle circuit you can change. This doesn't have as big an affect as changing the actual pilot jet does, so it can be used to "fine tune" the idle circuit. You can achieve richness levels in between pilot jet sizes by changing it. And the jet is nothing special, not an actual dedicated air jet, but rather just a small round main jet (as used in the BS38s), but in this case it flows air, not fuel.