BS34SS carbs. Now I get them. GS1000GT

[bobasoozoo]

Sometimes it takes a good kick in the ass but I finally get these carbs.
Bike is now running well enough that I can see how setup goes.

Choose main jet for good WOT response. >6000
Set slide needles for good midrange. 2500 to 5500-6000
Set pilot screw for good low end and idle. 1100 to 2200-2500

Multiple iterations may be required and pilot needle range may have to be adjusted
by changing pilot jets.

Would have been much easier if I'd
1)torched and easy outed out the glued in pilot screws from the git-go.
2)Not had to deal with timing jumping about because of sticky weights-sleeve on governor. Actually if I'd known to check this we'd be way ahead of where we are.
3)had decent airbox boots
4)Not had to replace ignition wires (HT) and plug boots.
5)Had a decent front tire for test rides from the beginning. You can't tell it's right if there's no load on the motor.
6)Had carbs that hadn't been monkeyed almost to death.
7) Done all this before!

In any case I'm very happy with progress on bike that had not run since 93 and has had a good dozen previous owners going at her. I can see her being ready for the road real soon now.

That's it for me until around the tenth. Off for some Pacific island time Tuesday.

[gsBert]

ok, you win the noob award man!

jet sizes, needle settings and all that are NOT rpm dependant, but THROTTLE POSITION. (heck, you can redline your bike without ever getting off the pilot circuit, and changing the main jet wouldnt affect it ONE BIT)

put some graduated masking tape on your bars and do plug chops (look up what a plug chop is) at various openings under load (a long uphill in 3rd gear is good)

1/8 is good for pilot
1/4 to 3/4 is needle jet
3/4 to WOT is main jet

you might want to google basic carb theory before you mess with jet sizes.
you'll save yourself a lot of grief.

[bobasoozoo]

Is that award suitable for framing?T
Thanks for ass kick.

Bike will rev fine sitting on the stand.
It's on the road that it's misbehaving.
Will try the tape trick to confirm but I still suspect it's still midrange that's off.
I'm catching plane, ATL-HNL, in about two hours so won't be able to work on bike for a couple of weeks. Have repeated 'throttle position' enough times to stick it in brain.

Thanks,

-Bob

[gsBert]

if your midrange (throttle opening) is off, suspect the needlejet/main jet combo. make sure the emulsion tub eis clean then start raising hell (i mean the needles).

do plug chops to see if youre lean or rich.

[bobasoozoo]

Thanks.

Yes, I think it's pretty much narrowed down to needle needing to come up a bit. At least for this level of tuning. As she's very flat between 2500-5500 when going from steady 2nd gear ride at 1500 to WOT. She pulls good up to 2500 and over 5500. The mixture is controlled by the needle in this range because there is not enough vacumn available at WOT to fully raise the slide. After 5500, slide is wide open and it's pretty much the main jet. Once I get rid of the flatness, I'll do the plug chops to fine tune things. Based on others posted experiences, I believe the 120 main should be close for the pods with stock exhaust that sounds like it's had a couple of baffles pulled but isn't near noisy enough to be wide open. The 200 pilot may be a tad small based on 3.5 turns for good idle. They all peak idle at about the same place so if there is an air leak, it's common to all four carbs and it would be very useful to know what sort of vacumn level is 'normal' for idle on the GS1000GT. I bench synced the carbs with a micrometer at 1/2 throttle. The same feeler wire size shows all four the same with plates almost closed.

Anyway, I plan to raise all the needles 1/2mm and see what sort of change occurs. If she pulls good through whole RPM range, (Again going straight to WOT from 1500RPM steady ride in 2nd) I'll take her out on the highway and if full range is still pulling good in 3rd gear, do some plug chops. I'm gonna need a new rear tire for any testing over about 70-80mph. Tire looks good and isn't checked/cracked, but it's over twelve years old. I'm not comfortable running any faster on an old tire that I haven't seen the inside of but don't want to drop $100 on a new one until I get the mechanicals sorted out.

-Bob