Yet ANOTHER new guy! Carb/Air box question...

[Lucky23]

Hey All-
Im new here, so please be patient! I bought a 1980 XS1100 in fair condition and it seems to stumble and pop out the carbs off idle when I give it gas, then revs up fine past that. Any input would be great. Also, it has PODS currently on it, but I purchased an airbox from a '79 because I was told the bike wont run correctly without. Does anyone know where I can find a diagram or schematic of the airbox so I can assembly it correctly? Thanks in advance!!

[slow mo]

hi lucky

don,t be so quick to blame the airbox ! these bikes will run great with pods its time to diagnose your problem starting with your carbs they should probably be well cleaned,, how does the inside of the tank look? has the bike been stored long? there is an article on what to look for in a new purchase ,,hopefully another member can tell you where to look just my 2 cents ,,ride safe ,,slow mo!

[natemoen]

It was disassembled when you got it?!? They are quite the puzzle when you werent the one taking it apart, heck they are hard to put together when you do take them apart! I looked at the parts diagram but that is pretty confusing to look at for an assembling purpose but here it is:



As to the other things. Most likely it sounds like your pilot circuit is plugged up some. If you dont know if the carbs are clean and the bike is new to you I would suggest pulling the carbs and cleaning them so that you know they are clean, and it will most likely solve other problems down the road. Check out this thread for help.

http://www.xs11.com/forum/showthread...b+cleaning+101

What kind of exhaust do you have as well?

Welcome and we like pics of your rides too!

[CatatonicBug]

Welcome aboard! As mentioned, lots of folks use pod filters. Some prefer the stock look with the airbox. Some have found the need to re-jet the carbs with pods, but not all. Definitely start by cleaning the carbs thoroughly. It's amazing how the smallest particles can really mess with the system. If you prefer the pod look, feel free to stick with it though. The airbox is a royal pain if even one of the 4 main bolts comes out of the top, so I can only imagine what you're in for if you have to assemble the whole thing from scratch!

[mro]

The air box is not that complicated.
Takes only a few minuets to assemble.
After you get the bolts and other parts together leave the bottom off while putting the top back in the bike. If the carbs are installed you can still fit the air box by removing the starter. Before you try to push the "JOINT, AIR CLNR 's" (rubber intakes on the air box) check that they are orientated properly by holding the air box so the joints are close to the carbs. Rotate the joints so they line up then push them on. If they don't want to go on because they seem to tight you can warm them up in some hot water, hair dryer or heat gun. Just don't get carried away and melt em

If you have a stock exhaust I'd use the air box which will make it easier to tune the carbs, (stock settings and jets etc).

BTW, if you pull the starter (3 bolts) be sure to either disconnect the negative battery cable or be careful to not short the starter on the engine or frame.

[Lucky23]

I dont have the stock exhausts. I just bought some MAC mufflers from a member on this forum so Im not sure what jetting I should use. Im not familiar with these bikes at all! Im very adept at wrenching on old Ironhead Sportsters and Triumph Bonnies, honestly. But I gotta admit, Ive really fallen in love with this bike! I plan on taking a 3000 mile trip this spring on this thing....

[Lucky23]

BTW, does anyone know of someone that has a parts book online for download?

[natemoen]

Yamaha has parts diagrams on their website www.yamaha-motors.com and member catatonicbug, (he posted a few post up here) has a link in his sig line that has a downloadable factory service manual.

Is the MAC exhaust a 4-2 or 4-1?

[Kit]

Greetings, and welcome! Nice to see a new member from the same general neighborhood. I'm southeast of you, just outside of Molalla.

Here's a link to Yamaha's online parts catalog: http://www.yamaha-motor.com/sport/parts/home.aspx

I'm having a similar problem with my '80 Special, and after eliminating almost everything else, it's looking more likely that I'll have to go into the carbs to see what's what (this is after a shop supposedly cleaned, jetted, and synched the carbs for me when I bought it a few months ago).

[crazy steve]

You can try downloading the individual pages at the Yamaha site and 'assemble' your own parts book. But to honest, I tried that and wasn't impressed with the clarity of the drawings on the few I downloaded and printed.

Then there's this seller: http://cgi.ebay.com/ebaymotors/ws/eB...K%3AMEWAX%3AIT. I've been eyeing this for a while, trying to decide if I want to spend the $22 to see if this is a 'better' job.

Yamaha never sold 'parts books' for owner use for these bikes, only service manuals...

[fredintoon]

Hey All-
Im new here, so please be patient! I bought a 1980 XS1100 in fair condition and it seems to stumble and pop out the carbs off idle when I give it gas, then revs up fine past that. Any input would be great. Also, it has PODS currently on it, but I purchased an airbox from a '79 because I was told the bike wont run correctly without. Does anyone know where I can find a diagram or schematic of the airbox so I can assembly it correctly? Thanks in advance!!

Hi Lucky and welcome,
OK, the stock airbox main problem is that it's in the effin' way of an easy carb. removal. With pods, 5 minutes easy work. With airbox, a half-hour of bloody knuckles.
Pods work fine so long as you don't use the el-cheapos that block off the small air holes around the main air intake.
Some have used plastic plumbing fittings as stand-offs to allow using the el-cheapos; others have used a sharp knife.
I use the oval tapered pods from MikesXS because not only do they work nice, they also have XS stamped on their ends.
Use the search button to find recommendations about jet size changes appropriate to pods and to less restrictive exhausts.
Who knows? The PO may already have made these changes.
But to me your stumble off idle says dirty carbs!
First, check the slow running needles. If they still have the EPA mandated brass washers that prevent access, those suckers have been in there undisturbed since new and there's 31 years-worth of crud in there that needs cleaning out.

[natemoen]

Hi Lucky and welcome,
OK, the stock airbox main problem is that it's in the effin' way of an easy carb. removal. With pods, 5 minutes easy work. With airbox, a half-hour of bloody knuckles.

After ya do it a few times it only takes about 5 min to get the carbs off even with the airbox.

Use the search button to find recommendations about jet size changes appropriate to pods and to less restrictive exhausts.
Who knows? The PO may already have made these changes.

Here is the link to the rejetting recomendations. Keep in mind that these are just starting point recommendations, you may find that you need to go up or down a little though.

http://www.xs11.com/forum/showthread.php?t=382

[fredintoon]

- - - After ya do it a few times it only takes about 5 min to get the carbs off even with the airbox. - - -

Hi Nate,
after my 3rd blood and bandaid session with the airbox it was on the shelf.
Perhaps I'm a slow learner?

[natemoen]

Hi Nate,
after my 3rd blood and bandaid session with the airbox it was on the shelf.
Perhaps I'm a slow learner?

I know how that is!

[Lucky23]

Thanks for the replies! Im going to take the carbs off this week and check/clean 'em out. Ill report how THAT goes. BTW, Im using dual MAC mufflers.