Where to get the correct airbox to carb tubes for a gs750lx

[Anonymous]

Help?
I cleaned out/went through the carbs on my '81 GS750LX. (I've already learned a couple things from some of the postings you have here)
But on reinstalling the carbs i've found that the 4 rubber tubes that connect the air box to the carbs have hardened over the years so badly that i simply cannot get them to conform or fit back onto the carbs. (they were on there wrong to begin with from the look of it.

I ordered a set from one local dealer. The new parts are about a quarter inch bigger diameter than the original. He has cross checked part numbers, my frame and engine numbers and says that Suzuki shows this "too big" tube to be the correct part number.
Another dealer says the same thing.

I believe the air box and carbs are original. (I bought it used from a guy a couple years ago)
The darn replacement parts are just too big for the gs750lx setup i've got.

Any ideas or suggestions would be welcomed. I've thought of going with a K&N filter mod and rejetting. Would rather stay with OEM.

Both dealers just throw up their hands and offer no help. The tube part number has been superceded a couple of times. Maybe some one goofed up.

Thanks,
shep

[Anonymous]

Carb tubes

Chances are those tubes are just plain vacuum hoses. take the old tubes to an auto parts store, have them match up the size and stick them on your bike for probably less than $2 a foot. See what happens.

[Anonymous]

thanks ot
that idea may be the easiest and certainly the cheapest way to go. These tubes are molded rubber with a bell mouth on the end inside the airbox, a land or groove where they fit in the box, etc. A nice piece of work, really.
Just wish I could keep the thing original.

[SqDancerLynn1]

I fought with my air box too. If the old ones are in good cond TRY heating them up with a hair dryer, tends to soften the rubber making it easier to put the air box back on If not try some from older model 79 or older. They used different carb.

[Anonymous]

Are they bigger both at the carb and airbox? Is the I.D. and O.D. larger? Maybe we can come up with a way adapt them with some more info.
Axel

[Anonymous]

Axel,

I used a caliper to measure the ID of the tube that fits onto the carb.
original part ID about 1.9 inch - suzuki wrong part ID about 2.2 inch.

Also checked the OD of the tube that fits into the airbox holes.
original tube OD about 2.0 inch - suzuki wrong part OD about 2.275 inch.

So, roughly about a strong quarter inch too large in diameter for the part Suzuki lists as the right one.
I did not get the lengths or bother to measure the bell mouth diameter that is on the end that goes inside the box.

I'm going to go to our local motorcycle junk yard (it is a sight to behold) and hunt around for some tubes and see if some of the old models might have some clues.
What do you think ?
Thanks for the reply
rick

[Anonymous]

If the length is okay you might be able to use them. What I would do is shim up the carb O.D. to match the boots. Try some thin, double-sided automotive foam tape (the stuff they use to hold emblems on cars) and use it to attach a strip off rubber (the correct thickness) around the intake of the carb. You can find the tape at an automotive paint store and the rubber at www.mcmaster.com. If your airbox hole is to small, just enlarge it to match.
Axel

[SqDancerLynn1]

As I sugusted earlier check on older models Air box boots are smaller on the older bikes WHAT type of carbs do you have?? newer style uses 32bs vacuum type carb older style uses slide type carb and the air box tube are smaller. Someone may have changed the carbs ?? If you can identify what type of carbs you have you should be able to find boots to fit. DO the job right or you will just end up doing it again next year

[Anonymous]

I checked part numbers for the '80 and '81 L model and both were same. Original part #13881-49200, superceded to #13881-49021, is this what you purchased?
Axel

[Anonymous]

Shep,
Also checked the part number for the GS1100LT, it shows the same airbox boot as the 750 even though it has 2mm larger carbs. ??? If it were only 2mm bigger I would say you could still use them, but you're seeing about a 1/4" diference right? Are you certain those are the original carbs? maybe someone put some 29mm smooth bores on it, that was a popular modification back then.
Axel

[Anonymous]

Axel and Sqdancerlynn1, you folks are great to help me figure this out:

These carbs are the BS type not the VM (I used a correct Clymer manual and it was very helpful and all the pictures and even the float level measurement were just what Clymer showed for a BS) They have a diaphram-operated metering pin that varies the size of the fuel path just below the main jet.

The outside diameter of the carb inlet where the tubes go on is just about 2.1 inches - right about 52mm (still can't think in metric)

For sure, these parts Suzuki sent and the part number checks out in their system (I had two dealers chase it) are a solid quarter inch too big around inside, outside - the old tube will fit inside the replacement.

What is is 32BS? is that 32 a diameter I could check on these carbs?

Hope this info helps you help me.
tx
rick

[Anonymous]

Shep,


I don't know what the BS stands for but that's the correct O.E. type carb for your bike. The 32 is the metric I.D. at the engine side.

You say the O.D. of the carb at the inlet side is 2.1" and the I.D. of the new boot is 2.275 so the difference is really about an 1/8".

I've checked several fiche cards and everything points to the part number you have. I used to work as a parts guy for a Suzuki dealer and although I agree a part number mistake is possible, I never saw one. I think, most likely, that the intake boot shrinkage was such a problem that Suzuki re-designed it larger, hence the superceded number.

I think I would go ahead and try to install them as they are. See if you can clamp them tight enought to seal. If so, once installed and run for a while, they may also shrink a bit and fit better. If not, you're going to have to fill that gap.
Good luck,
Axel

[Anonymous]

it seems that I have the same problem with my gsx750L 80

but my carbs are too big


to be the most visible as possible, is it better to continue here or begin a new thread ?

V++
Rackham[/u]