Suzuki 2 Strokes

Have a T250/T350 with new Suzuki float bowl gasket that drips a bit.
No drips when on the center stand but drips a bit when on the side stand.
Also have some cruzin image carb kits and noticed their float bowl gaskets are a bit thicker.

Questions before I pull the carbs off:
How tight should the screws be (should I loosen or tighten the screws)?
Should I switch to the cruzin image gaskets?

Sorry for the newbie questions, but I’d rather not pull the carbs off more than once.

Have some spare T350 carbs from eBay & checked the sealing-surface flatness of one of the spare float bowls.
Visually I’d say it was bowed by perhaps the difference in thickness between the stock & cruizin image gaskets.


Also ordered these level gauges to determine the actual level.
Anyone know what the fuel level should actually be?

Bowls were bowed that much when not torqued? wow. I'll check some when I get a chance.

Could you sand them flatter by hand using a piece of sand paper on a good flat service?

Can you get another bowl? if you search on the gasket you see it will fits many other bike like GT250 and maybe the bowl is the same... I think I have both carbs if I can dig up and comparelet me know

After market gasket I find are either too hard seal or too thick and soften like jelly and leak. Then I think they would also bow. Buy OEM

I checked a spare bowl that I was not planning to use.
The brass vent tube sticks out too far to sand the bowl on a flat surface — the tube would have to removed, which is something else I don’t know how to do.

Don’t know what cruzin image makes their gaskets out of.
Based on Google searches, it seems like some car guys make their own gaskets from sheets of viton.
A lot of Mikuni needle valves have viton tips, so my guess is that viton is a good choice.

Did a bit of research, and its interesting that Kawasaki provided float level & fuel level specs for their two stroke triples.
And Suzuki provided both specs for the GS-series four strokes.

Later next week I’m going to look at the carbs on the bike.
At a minimum it will be interesting to see what the fuel levels are, and to see if tightening/loosening the screws with stop the leak.

Found an interesting post...
Per markush, “Yes, but it is given a tolerance of +/- 1mm, so it should not matter whether measured with or without (0.5mm-)gasket .
The setting should be identical for all three carburetors.

I recently controlled the real fuel level at a GT380 using transparent hoses, mounted in place of the float bowl drain plug.
The setting by Suzukis method was the same for all three, and OK.
But: the real fuel levels differed by 6 mm between the carburetors. One was OK, one tended to overflow sometimes, one was much to low.
This is due to slightly different weights of floats and slightly different (or worn) float needle valves.
Maybe too, once a float was resoldered, therefore a bit heavier.

The fuel level should be approximately in the height of heads of the float bowl screws.”


viewtopic.php?f=2&t=11656

Maybe take "The flat surface" and cut a slot so you can sand it and clear brass tube.. I was also thinking you could use a bowl from a early gt250.... same float gasket maybe. Once you get parts in spec, seams to me OEM gasket is the only way to go.

will this work

http://www.ebay.com/itm/SUZUKI-GT550-GT ... AV&vxp=mtr" onclick="window.open(this.href);return false;

Yes the Kawasaki triple web site has great info. Yes setting float level that way is very precise. It would be interesting to adjust the float height per Suz way then compare Kawasaki way between carbs to see relatively how precise the outcome was. Setting float height Suz way to me takes skill to at least be repeatable and error prone. Also would think the absolute level would be same as Kawasaki. Thanks for reminding me and I may also do this on my T350 restoration project.

Got pretty much the same result on my T350. (Note that the carbs must be horizontal for this check to be meaningful.)

Fuel levels are usually 3-4mm below the gasket surface. The real advantages of setting fuel level is that once they are all the same, you know that is one potential variable eliminated and you have a baseline in case you later chose to raise or lower the fuel level to tweak fueling.

I got a good bit more than 3-4mm. Am certainly no expert so I could be full of hot air on this.

I looked on the Suzuki GS forum. Fuel level for most of those bikes is 5mm. Some are 3mm or 4mm, and a couple are at 6.5mm.
Kawasaki two stroke specs didn’t the gasket surface as the reference, so those numbers weren’t useful.

I did look at the fuel level with the carb mounted. Mounted carbs are tilted a good bit as you can see from the stud.
If the fuel level was set to 3mm, I think the fuel level in mounted carbs might be above the motor-side gasket surface.

edit...
Or did you mean 3-4mm from the low side of the gasket surface when the carb is installed?

jabcb. If you set the float the Suz way via height then what you get measuring this tube level way is what it is. But I do agree the error is in how one sets the float height suz way. So if I did and you did it may be different. Of course i would be right and you wrong But if we do it correctly it should be the same as Kawasaki way. How repeatable were you when doing the two carbs?

It would be nice to know what the level should be this tube/Kawasaki way. What do you mean Kawasaki value not useful? Did they give value? if so, i would think they would be useful and very comparable to suz method. If not i would question how skilled I am at setting height.

Yes some carbs on a angle. If I had the spec for doing it this tube height was I would use the center of bowl (inline with needle jet) as the point to measure. So higher in front and lower in the back (air box side) when mounted. You would think the pilot jet would have been chosen accordingly (tad smaller), but no difference respect to jet needle and main. so setting on bench or mounted using center should be similar.

Fun Stuff

For a Kawasaki H1, the VM28 carb has a fuel level of 30mm. I haven’t found a very good explanation of it other than to use a special float bowl.
The special float bowl is likely clear & marked for the correct level.
http://www.kawtriple.com/mraxl/carbspec.html
http://www.3cyl.com/mraxl/manuals/carbtune/carbtune.htm

Have found more info the the Suzuki GS bikes.
Fuel level is measured with the bike at idle & on the center stand. The level is measured at the float bowl front-to-back midpoint.
Static level with the engine off can differ & may be either higher or lower than the spec.


For my bikes…
I’m having problems with the 1972 T250. Its fine on the center stand, but the carbs leak a bit when on the side stand.

I’m currently working on the 1969 T350.
It wasn’t running quite right under light loads. Turns out it didn’t have the 2nd pilot jets. Luckily I had NOS 2nd pilot jets in my parts inventory. Bike now runs fine.
The left carb was leaking a bit in that you could see signs of gas staining on the float bowl.

I wasn’t sure about the leaks.
Am an amateur/home mechanic & was thinking that maybe I’m not doing the float level adjustments correctly.
Did some research & decided to measure fuel levels.
The pic of the fuel level is for the T350 — both carbs have the same level.