Float height adjustment

Post your Kettle problems here and cures
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Bikesklade
Posts: 7
Joined: Sat May 15, 2021 9:16 am

Re: Float height adjustment

Post by Bikesklade »

Fully agree that the visual fuel level is a far better way of setting things up however the documented Suzuki method is as I have stated, I believe the floats I have set are correct to that method.

To be able you use the visual tube Fuel level height method, I would want to know what exactly is the height you are trying to achieve? as I have looked and I cannot see a confirmed height, Paul states that "most bikes" are set at 3mm is the GT one of those most bikes as I have seen measurements quoted on the internet for various bikes regarding float height of fuel level as being between 1 and 5mm even my local motorcycle dealer suggested that a measurement of 1-2mm would suit

Therefore I had no choice but to follow the official Suzuki advice, as a tool maker I found no difficulty in setting the floats accurately. The plug colour would also suggest its set correctly

Interestingly Kawasaki specify a fuel height for their KH range and yes I agree is a better way of setting the height, but only if you know what that height should be from a specification. Which Kawasaki do specify
teazer
Posts: 1035
Joined: Mon Mar 07, 2011 8:10 pm
Location: Chicago

Re: Float height adjustment

Post by teazer »

At the grave risk of appearing to contradict myself, the actual fuel level that you set it to doesn't matter as long as they are all set the same.. By that I mean that you will know what the fuel level was and can adjust from that starting point should you so desire/need. I set fuel nominally as 3mm below the gasket surface. If I think I need it to be higher or lower, I can adjust it and keep a record of the new level and the change it makes.

I have only set half a dozen sets of GT750 BS40 carbs using the float height method and after making sure they were all 100% spot on spec, I checked the fuel levels and found them not to be consistent. Whether that was twisted floats or difference in buoyancy or other reasons I didn't find out. I just made sure they were as straight as possible and set the fuel levels to be the same and it made a slight but noticeable difference to how they ran.

I totally understand that you had to do what you had to do and it's a testament to the relative insensitivity of a GT750 to minor adjustments. Get the timing out by a long way and it's often hard to tell the difference. Same with jetting. They are big old softies and usually, on a stock or close to stock motor, close enough is just fine.
SpeedOfDave
Posts: 3
Joined: Wed Dec 08, 2021 2:53 am

Re: Float height adjustment

Post by SpeedOfDave »

PaulD738 wrote: Mon Aug 09, 2021 8:03 pm The float height is just a guide so you can get the FUEL level in the carb bowl correct. I made these up for my Katana but I’ve also got some made up for my T500 and Kettle. You remove the drain plug and screw the adapter in. When the carb bowl fills up you can see the fuel level in the clear pipe. Most bikes are set at 3mm from the joint where the bowl seats against the carb body.
Where did you get the lovely drain plug adapters? I'm in the States and can not find them with the right thread pitch.


Sidenote: I'm new here. I'm working on a customer's GT750. Its a lovely bike but and the carbs keep leaking. Float levels are way high but I'm aware the proper way is with the adapters and measuring actual level.
Thank you for the help
barney01
Posts: 3118
Joined: Wed Sep 26, 2012 7:33 pm
Location: Prestatyn.Wales

Re: Float height adjustment

Post by barney01 »

NO SMOKE .......NO POKE
teazer
Posts: 1035
Joined: Mon Mar 07, 2011 8:10 pm
Location: Chicago

Re: Float height adjustment

Post by teazer »

Those should fit a GT550 and early J&K 750s. Evans Ward on the prior page makes some and he's in the US. I had a spacial banjo bolt machined and I finally got some adapters from Evans and his are much easier to use on a 750 with CV carbs.

I bought a set of 3, but you really only need one.
SpeedOfDave
Posts: 3
Joined: Wed Dec 08, 2021 2:53 am

Re: Float height adjustment

Post by SpeedOfDave »

teazer wrote: Wed Dec 08, 2021 4:20 pm Those should fit a GT550 and early J&K 750s. Evans Ward on the prior page makes some and he's in the US. I had a spacial banjo bolt machined and I finally got some adapters from Evans and his are much easier to use on a 750 with CV carbs.

I bought a set of 3, but you really only need one.
barney01 wrote: Wed Dec 08, 2021 9:08 am https://www.z1enterprises.com/fuel-leve ... uzuki.html
Here you go
Awesome. Thank you both. This is a 72 so a early model. and I've ordered from Z1 for vintage stuff before so ill try there.

Heres a pic of the 750 I'm working on. Not all original but she runs
263961969_598524791202654_8053310281142045921_n.jpg
263534449_279514224199574_1351831843466758876_n.jpg
teazer
Posts: 1035
Joined: Mon Mar 07, 2011 8:10 pm
Location: Chicago

Re: Float height adjustment

Post by teazer »

J&R Power Pipes by any chance?
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PaulD738
Posts: 3962
Joined: Thu Sep 25, 2014 6:57 pm
Location: Warrington Cheshire

Re: Float height adjustment

Post by PaulD738 »

SpeedOfDave wrote: Wed Dec 08, 2021 2:56 am
PaulD738 wrote: Mon Aug 09, 2021 8:03 pm The float height is just a guide so you can get the FUEL level in the carb bowl correct. I made these up for my Katana but I’ve also got some made up for my T500 and Kettle. You remove the drain plug and screw the adapter in. When the carb bowl fills up you can see the fuel level in the clear pipe. Most bikes are set at 3mm from the joint where the bowl seats against the carb body.
Where did you get the lovely drain plug adapters? I'm in the States and can not find them with the right thread pitch.


Sidenote: I'm new here. I'm working on a customer's GT750. Its a lovely bike but and the carbs keep leaking. Float levels are way high but I'm aware the proper way is with the adapters and measuring actual level.
Thank you for the help
I think you can buy them but I made my own on my little model makers lathe
They're rubbish them Jap bikes lad they won't last five minutes! you want to get yourself a nice Royal Enfield!
A quote from my old dad 8-)

I started out with nothing and I’ve got most of it left!
SpeedOfDave
Posts: 3
Joined: Wed Dec 08, 2021 2:53 am

Re: Float height adjustment

Post by SpeedOfDave »

teazer wrote: Wed Dec 08, 2021 11:15 pm J&R Power Pipes by any chance?
I just saw these replies. sorry.

I thought they were stock pipes. There's no markings on them but the customer bought it like this so unknown what pipes they are.
PaulD738 wrote: Fri Dec 10, 2021 11:53 am

I think you can buy them but I made my own on my little model makers lathe
I got some from Z1 but a nice bench top lathe and a mill is on the equipment lost if the shop keeps doing well in next couple years
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