I can't find the problem for the life of me... Gs400 1977

[Guest]

Two years ago, I finally got the bike running flawlessly, or so I thought. The carbs were perfect then suddenly, gas was pouring out of the overflow. One of the metal floats had a pin hole in it and it let too much gas in. I purchased new floats only not metal. Installed and I had amazing power throughout all bands. Then, again the gas started pouring out and it was due to incorrect float height. Now I've adjusted the heights to spec and there is simply no power. Bike runs and idles well. But the oomph has completely dissipated. It struggles going up hills and sputters as if it's about to go fast but then bogs down. Any thoughts? Change the float height more? Clean the carbs again?

[tom203]

No oomph!

of course check your petcock for correct operation, But I'd be suspicious of float height with these new plastic floats. Are you measuring it right? Have you seen this link?

http://members.dslextreme.com/users/bikecliff/images/carbspec_float_height.html#A02

[Zach]

My floats are round. I have the bs34 carbs. And I mean bs34 not bs34ss... I just raised the float height 1mm from 26.3 to 27.3. I took her out for a ride and noticed an improvement. I believe I'm going to try raising it another mm to lean it out some more and see if there's any more improvement. So far signs are leaning towards a too rich mixture.

[Steve]

Good to see that you understand that raising the number related to the float height actually leans out the overall mixture.

Yes, 26.3mm is the standard figure, but that is also with standard floats. More important is to get the FUEL LEVEL correct, which it needs to be, regardless of what float is being used. Find a way to measure your actual fuel level (it is illustrated in all the manuals), make sure it is 6.5mm +/- 0.5mm.

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