Carb breather tube

[bexabarr]

part number 15 on this diagram

http://www.bikebandit.com/partsbandit/assets/schematics/Suzuki/SU0093_013.gif

It appears that my breather tube is morphed (I suspect it was overtightened back when I was learning how to repair my carbs). The problem is that the needle gets stuck when it goes in. I have some breather tubes for a 650, they appear to have a few more holes, of which are also a bit bigger than my stock 550 breather tubes.

Question: I thinking of using all 4 breather tubes from the 650 and keeping my stock main jet (80)

Reasoning: the fuel has to pass through the main jet anyways - so that is what it is regulating the amount that gets through not so much the breather tube.

The problem that I foresee is that more fuel will get out around the needle through the bit larger holes and therefore richening the mixture.

Yes I know the answer to my question... get a new breather tube! and forget about the 650's.

Can someone explain flaws in my reasoning so I can sleep well after I've spent $20 on the breather tube having the others already laying around.

[DimitriT]

I think you are referring to the needle jet. It's possible that the 550 and 650 share the part. Check the # on the parts catalog. If not, then I would be concerned about running rich or lean on the needle circuit. The main jet regulate flow only near WOT. Its the needle jet that regulates flow past about 1/4 throttle to almost WOT.

[bexabarr]

Thanks for the response. It makes perfect sense. I'm going to look around for a needle jet for my bike. Anyone know where I can find one? Does anyone have one from a parts carburetor they are willing to sell me?

Vm22ss carbs
79gs550

Thanks guys.

[bexabarr]

at alpha-sports it says the part I need is called the breather tube part 15 - they sell it for $19

http://alpha-sports.com/spst/1979%20GS550L/06.htm

I did a quick parts number search and found this on ebay

http://cgi.ebay.com/ebaymotors/Suzuki-Carb-Pipe-Breather-84-DR100E-13385-47030_W0QQcmdZViewItemQQcategoryZ35597QQitemZ4645863059QQrdZ1QQsspagenameZWD1V

same parts number but for an 84 DR100E - looks like the same part but I thought they stopped making vm carbs by then. Because they have the same part number should a I assume they are the same part?

[bexabarr]

also here are two pics... The one with the o-ring is off my gs550 the one without it is actually off a sv650 not a gs, which has vm24 carbs.






as you can see with the second pic the only difference is that the 650 has 12 holes while the 550 has 10. Sorry they came out a bit blurry.

Should I buy a new part to replace the broken one? Should I use the one off the 650? and if I do, should I replace all of the ones on my 550 with the ones off the 650 or just the one that is messed up?

Keep in mind that I would keep my stock #80 main jets. Thanks again.

[bexabarr]

anyone? cause I won't be able to ride until I get this figured out... and these days have been so nice!!