Float Height Tool

[Shuriken]

What kind of tool are you guys using to measure your float height? Caliper? Engineering ruler?

Ben

[Winterhawk]

Vernier Calipers

[skids]

Digital calipers (I hate using verniers due to my stigmatism).

Originally posted by Winterhawk
Vernier Calipers

[Ken Talbot]

Digital caliper here, too. Set yourself up so you have a nice bright background. Watch the sliver of light disappear as the caliper just touches the float body:

[skids]

I see that you measure the distance with the gage slider NOT on the central rib. That is the way I do it also. I am not sure what the manuals mean by "Gasket Mating Surface" because my optimal settings are always a bit different than spec.

Originally posted by Ken Talbot
Digital caliper here, too. Set yourself up so you have a nice bright background. Watch the sliver of light disappear as the caliper just touches the float body:
[IMG]

[Shuriken]

Looks great. So, Ken, where do I get one just like the one you're using?

Ben

[prometheus578]

Mine may have come from Harbor Freight Tools, can't 'member.

[GNEPIG]

.. I got this from K&L, I don't remember how much it was but it was cheap.. it reads in mm and is very hard to make a mistake with ..i checked it with my dial indicator and it looks to be accurate

[RiskyBusiness]

The caliper that Ken is using looks a lot like mine... from Harbor Freight.

Correct me if I am wrong Ken, but it looks like he is using the ass-end of the caliper (depth guage) to measure the distance. It's a good trick but not entirely obvious if you aren't used to calipers. What you are seeing in the pic is the butt of the caliper and the jaws are up in the air.

HFT has a digital 6" caliper on sale for $15. You can't beat that with a stick. Well I guess you could but then your caliper would be inaccurate... Good ol' Chinese engineering.

Here's the link.

[Glarusguy]

Great pic Ken. I've seen so many posts while searching and everyone explains it different. A picture does say....
One thing that always messed me up was when the float needle's spring would be sticky. Clean,clean,clean!

[Shuriken]

Slick. Thanks guys. Now I'm off to see which one to buy.

Ben

[Ken Talbot]

Riskybusiness - you are correct, I use the depth gauge end of the caliper:


Skids - yes, I measure to the flat part, not the rib. At the same time, I also measure to what appears to the highest point of the float body:


It's not really so important what you measure. The thing that matters is that you do it the same each time.

[motoman]

I also notice all the pics have the carb upside down. This can create a "false setting". The carb assembly should be tipped on its side, tipping back slightly as to let float just seat needle, then measure. Upside down causes weight of float to flex metal tang it hangs on causing an incorrect reading which will result in a too high float setting. I tipped mine on its side, used a two piece float gauge out of one of many Napa carb kits I've done on GM Quadrajets over the years. That gauge is in incriments of 32's and worked very well, as the difference between 23mm and 27mm comes out to be only bout a tenth of an inch. converting mm to what I understand was way easier, and set mine on my 81 H tourer at 27mm.....no starvation all the way up to redline and all plugs are light-whitish tan, which is at 5000 ft. elev. Anyway, doing all the same is the key, and upside down WILL cause a higher float level setting.....guarenteed!!!

[prometheus578]

Just my opinion

I doubt the weight of the float will cause the tang to bend. I base this on the amount of force I need to use with a small screwdriver to adjust the tang in the first place.
Secondly... all the service manuals show the carbs up side down when adjusting. The tang doesn't bend, but the springy nub on the needle does retract a bit. I figure that the original Japanese engineers that designed this beast knew about the needle's characteristics and such, and designated the float height proceedures accordingly. ( I wasn't there... just my thoughts)

[motoman]

just my opinion

I'm sure whatever choice, upside down or slighty past horizontal seems to be working for eveyone. That was just a bit of info, as a Yamaha service tech, who had been factory trained for all the bikes of that era held my carb assembly in both positions and showed me what takes place when assembly goes towards totally upside down, rather than tilting assembly till floats fall till needle just seats. There is quite a noticable difference to the eye. Anyway, that's kinda why I also added that the difference between 23 and 27 mm is minimal for the specs. on the different years. That procedure as per Yamaha was for those that may be experiencing some over-fuel or flooding situations, and my 81H is liking the 27mm at the 5,000 ft. elev. where I live. For the most part, everything goes up from there, unless I travel more than 400 miles in any direction. Just something I learned this past week from someone who especially knows and likes these old XS's, and had been schooled in them.