Replace Brass floats with Plastic ones?

[Guest]

Where I live the temperature changes cause the brass floats to compress, changing my float height of course.
Question, can I use plastic floats from newer carbs in a carb body that originally came with brass floats?

[habsdoc]

I live where it can be +100 degrees F in the summer and I still ride now at 25 degrees F and I don't seem to have any problems.

[steve murdoch]

Never heard of a brass float changing shape due to temperature.
Are you sure it is not a pinhole or split seam?
If you put your location in your signature a helpful GSer might be nearby.

[system9]

The brass floats went from convex to concave in shape, both the exact same amount. One day my bike was leaking gas, and I know it used to be fine. I had to re-set the float levels to compensate for the warped floats (they still float though)
I read this on another thread concerning the same issue

"Thanks jabcb for the link. That bulletin explains the damaged float issue completely.
I have heard about bikes being parked outside in freezing weather for a long time and the gas in the bowls freezing and collapsing the floats"

So the question isn't whether or not brass floats can compress, cause they do, and I have some that have. I'm wondering if I can use the plastic style ones from the next series of carbs, or is the shape of the plastic float not going to work on the carb bodies that came with brass floats?

I live in Ann Arbor MI, I'll add it to my signature. Thanks.

[eil]

Hi system9, I live in Ypsi and work in AA.

So the other replies are right, brass floats don't normally change shape. Like you suggest, it could theoretically happen if ice forms in the float bowls. But gas doesn't freeze easily (I believe it will turn into a gel at truly arctic temperatures, not the mild stuff we get here) so the only way for that kind of damage to occur is if your carbs somehow got filled with water. Did you store it outside? The only other scenario I can think of is maybe you bought some gas with a high ethanol content, it attracted a lot of water, leaked through the petcock and into the carbs where the gas evaporated faster than the water. But that's a guess and probably something of a long shot.

Regardless of how, if water froze inside your carbs, it could have very well damaged the jets and internal passages too and you might not be able to tell just by looking. If it turns out the rest of the carbs is miraculously okay, then winterizing the fuel system this year would not be a bad idea. I treat my gas with Sta-Bil, fill the tank up, drain the carbs, disconnect the fuel line, and push the bike into the corner for the year.

To answer your question: judging from the parts fiche, your carbs look similar to those used on 4-cylinder GSes but the float bowl design is different (roundish), so I doubt the floats would interchange. The part number for the float is 13252-31210 and was used on a bunch of 400s and 450s, so it shouldn't be hard to find good used ones. (Or $25 each for new, which honestly isn't that bad.) If you want to see whether any aftermarket manufacturers made plastic floats, you can put that part number into Google and see what pops up.

[steve murdoch]

A bit of an oddity on these aftermarket floats.
It lists a pile of Suzuki and Kawi bikes that they will work on including the '83 GS450T but not the '82 GS450T.
I wonder if the brass floats were only used for that one year and if the carb was a one-off as well.

http://www.ebay.com/itm/K-S-CARB-FLOAT-MIKUNI-/141500458961?hash=item20f215a7d1:g:qOYAAOxyLm9TAkax&vxp=mtr

[system9]

Thanks for the info. The bike is stored in the garage, at the last possible moment before hard winter hits ;-)
I usually put some seafoam in the tank. I'm going to say now, because of popular opinion, that the floats did not compress because of cold or pressure. I'm not exactly sure why they are convex. These carbs have alot of oddities to them. Even with years that are supposed to to be the same, I've seen needle jets that won't even fit into the bowls. At this point the floats still do float, so I will continue to use them, with no more worries that they are expanding or contracting. Thanks for the input.

[system9]

[QUOTE=eil;2241708]Hi system9, I live in Ypsi and work in AA.

Nice to meet you Charles, I live right at Packard and Platt. My son Ian used to be in the Motorcycle class at Washtenaw, He lives in Ypsi and often rides my GS around. Its possible you've seen it (or heard it) This is Ian on my GS on the right

http://img11.deviantart.net/6226/i/2015/315/8/a/gorilla_bees_by_5bodyblade-d9ge2ga.jpg

[eil]

Cool cadre you've got going there, I think I even see some spares in the garage. I commute into work on my GS almost every day in reasonable weather. Have you been by bike night in Depot Town? I was able to make it a few times this year and have up with a few fellow GSR forum members there. If you haven't been, it's usually quite a spectacle. Lots of nice and sometimes unique bikes but by about 8 p.m., mostly taken over by the Harley crowd.

If you ever need a hand with bike maintenance, let me know. I love working on bikes but mine is running just fine. :P