I have seen some info about XS400 4g5 models & float hights, have been to xs400.net and finally tried to set it myself.
I came to the following conclusions:
1)use a normal hairdryer to warm up rubber stubs before reinstalling carbs - it makes miracles (especially in a cold garage)
2) the float level hight, confirmed by "pipe method", is about 21-23mm depending on where exatclty you measure; the plastic floats have ca. 1.5mm difference (see the picture); I measured 21mm with gasket on, on the lower surfce of the float;
3) I have noticed, that needle valves differ between older/newer (or just different) sets; It's not easy to measure but looks like it's about 0.5mm in length; so when replacing - always use the same on both sides; make sure the spring in the valve makes floats "bounce", I have got a new repair kit with broken spring and had to replace that
4) after 30years of usage the steel "frame" holding floats bents and twists; you can check it by pressing the float against the needle valve (gently, but all the way down) and measuring the floats; it may suggest ie different settings between carbs if values differ; the only real method to check fuel level is with the "pipe method"...
5) always have fire extinguisher and wear gloves when working with carbs
6) in 4g5 model it's quite complicated to tak carbs off; make sure you have done really all other things (spark, timing, valve clearance) before even touching carbs
hope this helps someone
regards
Oscar the grouch.
I came to the following conclusions:
1)use a normal hairdryer to warm up rubber stubs before reinstalling carbs - it makes miracles (especially in a cold garage)
2) the float level hight, confirmed by "pipe method", is about 21-23mm depending on where exatclty you measure; the plastic floats have ca. 1.5mm difference (see the picture); I measured 21mm with gasket on, on the lower surfce of the float;
3) I have noticed, that needle valves differ between older/newer (or just different) sets; It's not easy to measure but looks like it's about 0.5mm in length; so when replacing - always use the same on both sides; make sure the spring in the valve makes floats "bounce", I have got a new repair kit with broken spring and had to replace that
4) after 30years of usage the steel "frame" holding floats bents and twists; you can check it by pressing the float against the needle valve (gently, but all the way down) and measuring the floats; it may suggest ie different settings between carbs if values differ; the only real method to check fuel level is with the "pipe method"...
5) always have fire extinguisher and wear gloves when working with carbs
6) in 4g5 model it's quite complicated to tak carbs off; make sure you have done really all other things (spark, timing, valve clearance) before even touching carbs
hope this helps someone
regards
Oscar the grouch.
