where to find a vacuum diaphragm

[audijunky]

Hello fellow owners,
Just purchased a 1978 xs1100, not sure which model, not a special, just says xs eleven on the side covers. It came with a wind jammer. Any way It appears to be missing its vacuum diaphragm. Where is this part supposed to be located on the bike? I have a Clymers manual and it looks like it is supposed to be mounted infront of the carbs? Any one know where I can purchase one. Checked some of the web sites listed on this site and nothing. Please help. I really really want to revive this old beast. Thanks

[xssiveone]

Re: where to find a vacuum diaphragm

Originally posted by audijunky
Any way It appears to be missing its vacuum diaphragm. Where is this part supposed to be located on the bike? I have a Clymers manual and it looks like it is supposed to be mounted infront of the carbs?

There is only one vacuum diaphram on the standard models and that is located at the left end of the crankshaft under the timing cover.

Are you sure you're not confusing the vacuum diaphram with the fuel control valve on the Special models? The standards have the vacuum controlled fuel shutoff in each petcock, the special models have what looks like an octopus with all the fuel and vacuum lines running to it.

[audijunky]

yeah I am thinking about the octopi. I am beggining to think that mine isnt supposed to have one. So where does the vacuum line from the engine crankcase connect to on the standard. from looking at my bike and the clymers manual I have two fuel lines(one for carb1&2, one for 3&4) that go to the carbs one for each petcock. Two vacuum lines from the intake tube after carbs 2&3 that go to the petcocks.Intake tubes for carbs 1&4 are capped.( the same spot that the vacuum lines are connected to on 2&3)Does this sound right. (Not sure cause when I got the bike most the vacuum lines where disconnected.) It also had the vacuum hose connected to the crankcase but the other end was not connected to any thing. No Idea where it is supposed to be connected.In the manual I have it only shows how to hook the vacuum lines up with a octopi. Any help would be greatly appreciated. Thanks for your information xxssiveone.

[xssiveone]

Yes, I think that's about right... don't have the manual in front of me so can't confirm it. Fuel lines from petcocks to 1/2 and 3/4 to left and right petcocks respectively. Vacuum lines from intake boots, not sure it matters here which ones but for estetics I always did intake boot 2 and 3 to left and right petcocks respectively. Vacuum line from left crankshaft end of engine connects to the nipple on carb #2, not to an intake boot which is a common mistake. Nipple on carb #2 has a restriction in it to meter the amount of vaccum to the advance mechanism. All other vacuum points must be capped in some manner.

[audijunky]

Thank you very much XSSIVEONE , you my friend are the man. You would think that a Clymers manual that is supposed to cover the model I have would show the alternative to having the octopus vacuum setup. I actually got to looking at the bike last night and noticed the nipple on carb 2 and kinda of suspected that was were the Line from the crankcase went. Thanks for confirming. This site is great.