Troubleshooting BS34's on my GS850

[XXWoodmanXX]

Oh man!!! First day to peak over 50 degrees and I took FULL advantage of it.

Finally tuned the BS34s to my bike. I took Steve's advice and turned out my mixture screws, but it took a whopping 1 1/2 turns, totalling 5 1/2 turns out!! But when I blipped the throttle, it was just that....a blip. It quickly returned to idle. Sweeeeet.


But she's now running ALOT better, and pulling strong thru the entire RPM range and all gears.

Just in time to have to pack it up and put her away for the winter. *sniff-sniff*

Overall, very, very happy!

[Steve]

With them turned out that far, I would suggest going up one size on the pilot fuel jets (use 42.5, instead of the stock 40), and you will be able to get those screws turned back in to where you will still be able to adjust them. With them out that far, you are at (or just past) maximum, and can't really do any adjusting.

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[XXWoodmanXX]

Got it. 42.5? Or would you recommend just going with 45? Thx!!

[XXWoodmanXX]

I JUST found a set of 45's, and I'm thinking I put the set of 40's from the BS32 genuine suzuki rebuild kits.

Uuuuhhhhhh, I think I just found the Achilles' heel to my carb problem. lmao!!

[Steve]

As I mentioned back in post #6, stock jetting for both sets of carbs for their intended bikes, used #40 pilot fuel jets. You are using these carbs on a bike for which they were not intended, so jetting will have to change. I think you have noticed that by now.

How much to change? One jet size is usually about the same as three turns of the mixture screw, so going up one size (to 42.5) should bring your screw settings down to about 2 to 2 1/2. If you were to go up two sizes to #45, you might have to run with your screws all the way closed, and it might still be too rich, because you can't slow down the mixture to where it needs to be.

For the price of a few jets, I would get the 42.5s, but it's your bike, feel free to install the 45s to see if they are, indeed, too large.

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