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Better off using petrol as anything else has a different densities and the floats will be at different levels, just be sensible and you will be fine.
Rule of thumb: the floatlevels are NEVER wrong unless floats have been messed with. I sure hope this American epidemic doesn't spread here.
Quote from: deltarider on May 14, 2018, 07:58:51 PMRule of thumb: the floatlevels are NEVER wrong unless floats have been messed with. I sure hope this American epidemic doesn't spread here.As bike is 40+ years old, Rule of thumb is check the float levels, as you never know what previous idiots, err i mean owners have done.
Quote from: kevski on May 14, 2018, 10:13:29 PMQuote from: deltarider on May 14, 2018, 07:58:51 PMRule of thumb: the floatlevels are NEVER wrong unless floats have been messed with. I sure hope this American epidemic doesn't spread here.As bike is 40+ years old, Rule of thumb is check the float levels, as you never know what previous idiots, err i mean owners have done.Unfortunately too many mistake another problem for an incorrect floatheight. Incorrect fuelline length and diameter (kinking), good-for-nothing 'extra' inline fuelfilters that intermittently hinder fuelflow and sticking valveneedles. It takes very little indeed, to disturb the gravity feed of just a few centimeters difference in height. I would start with having the correct fuellines and - especially after hibernation - eliminating sticking valve needles. An additive may help. I myself have never encountered a CB500/550 float that needed to have it's tang adjusted.The correct dimensions for CB500 fuellines is 18 and 30 cm (old style petcock) or 17 and 28 cm for models that had the newer type petcock. ⌀ 5,5 mm.
Quote from: deltarider on May 15, 2018, 07:09:16 AMQuote from: kevski on May 14, 2018, 10:13:29 PMQuote from: deltarider on May 14, 2018, 07:58:51 PMRule of thumb: the floatlevels are NEVER wrong unless floats have been messed with. I sure hope this American epidemic doesn't spread here.As bike is 40+ years old, Rule of thumb is check the float levels, as you never know what previous idiots, err i mean owners have done.Unfortunately too many mistake another problem for an incorrect floatheight. Incorrect fuelline length and diameter (kinking), good-for-nothing 'extra' inline fuelfilters that intermittently hinder fuelflow and sticking valveneedles. It takes very little indeed, to disturb the gravity feed of just a few centimeters difference in height. I would start with having the correct fuellines and - especially after hibernation - eliminating sticking valve needles. An additive may help. I myself have never encountered a CB500/550 float that needed to have it's tang adjusted.The correct dimensions for CB500 fuellines is 18 and 30 cm (old style petcock) or 17 and 28 cm for models that had the newer type petcock. ⌀ 5,5 mm.You are missing the point, Check does not mean adjust and previous owners, to blythly refurb which original poster is doing without checking everything would be foolhardy.
The manual only shows a measurement with the bowl removed, with the carbs on their side with the float tang just touching the needle. It should be 22mm from the flange to (what is) the bottom of the float.But 2mm below the flange for the (so called) clear tube test is what I use.The tang is pretty stiff and will not change unless interfered with, but aftermarket needles may alter level.
May sound a daft question but am just rebuilding my carbs and wondered if i can test the float level using water (off bike of course !!!)Just hate messing around with petrol all over the place But maybe water has some different physical property from petrol that means its not feasibleAlso does the level need to be about 2mm below the bowl/body joint from memory?
Quote from: paulbaker1954 on May 14, 2018, 04:56:18 PMMay sound a daft question but am just rebuilding my carbs and wondered if i can test the float level using water (off bike of course !!!)Just hate messing around with petrol all over the place But maybe water has some different physical property from petrol that means its not feasibleAlso does the level need to be about 2mm below the bowl/body joint from memory?I found that testing with water doesn't work! I had a fuel drip from the float bowl overflow pipe on my 400/4. It had new float valves but I checked the one that was dripping for dirt and made sure it was seating ok. Still dripping. I'd read that the brass overflow pipes sometimes crack and cause a leak so I took off the float bowl again and filled it with water. No leaks, so it must be ok, right? Wrong.Well known issue is hairline cracks in the overflow pipe. I once spent ages trying to chase down what I thought was a float valve not seating only to eventually spot this hairline crack I tried fixing it with jd weld but eventually petrol ate its way past it and gave up and sourced a new float bowl but they are getting harder to find at sensible pricesWhen I checked the bowl again with fuel it didn't leak at first, but after a minute or so it started dripping very slowly and the outside surface of the external pipe was wet. It must be finding a way down the side of the pipe between the aluminium bowl and the pipe.I won't check with water again.