One for the XJ Owners

[Cobia]

This one is for those of you who are still using the stock airbox.
Have you found any tricks that will make it easier to remove the carbs on that bike? The design does not provide much wiggle room in there, much less than in the stds or the specials. I mean, they're tighter that a gnat's a$$hole stretched over a manhole cover!!!! Geezzz!!
I'm still trying to smooth out the power curve on it and after going in there and adjusting the float levels three times until it's almost drowning, I get hesitation in the 1.5K to 2.2K rpm range. I'm considering going with 120 mains and 50 pilots. What do you think?
My plugs are still white so I'm not flooding it so I figure I can feed it more fuel, at least in the lower range it might do the trick. But getting the carbs out of this one is a major PITA.
I put 120s in the '79F (thanks to BikerPhil) and it screams. I'm not so worried about MPG, I just want it to run smoothly throughout the power band.
I guess that's two things for the XJ Gurus!!

[trbig]

With everything stock, I just have to wonder why you're trying to jet it so far FROM stock? As long as your YICS is still hooked up and you still have stock exhaust, you shouldn't have to get away from the stock jetting. Just make sure everything is clean clean clean, then you should be able to adjust it to work the way it is. Have you removed the brass caps over the mixture screws?

Sadly, I don't think there's an easy work around for the carbs with the original box. I tried and tried. Even taking all the bolts OUT of the airbox doesn't give you any more wiggle room. This is the reason I went to pods.


Tod

[devilschld]

there is no easy way with the box. but get out the cuss words first and do it

[Cobia]

The curse of the XJs

Yeah, I guess that if we want the stock look we'll have to live with the tight quarters. Where can you get the airfilters for the stock box???

Anyway Tod,
The carbs are superclean, we've had them out three times for float adjustments to enrich it, because it just starves for fuel. Plugs never foul, typically indicate that it's running too lean!!! The idle mixture screws are out at least 5 to 6 turns!! That's why I'm thinking about going with the 120 mains and the 50 pilots. Although my suspicion is that larger pilots will take care of the issue w/out the larger mains because of where stuttering happens. But considering the high end power of the 79F when we put those in....... What's a few bucks for that kind of response?

Thanks, I'll keep you posted.

[cruiser]

Where are your floats set right now?
Mine are at 23mm and idle screws after sync are 4 to 5 out. Mine is pure stock everything. I seem to remember other XJ owners idle screws out further than an XS settings from past posts.
I still have white on the plug tips and part of the core but around the outsides are just a bit darker. I've always wondered if it was still a bit lean but accelerates smooth all the way with power and no sign of excessive heat on piston tops (boroscope).
I played around with float settings last year and this is where it's best on mine and also bench test with clear vinyl hose to check float level and at 23mm was right where manual shows it should be.
No tips for carb removal although after many times I found getting them out from the front boots first is better as the air box boots are more flexible.

[yadada]

I put 50 pilots in mine to get rid of popping on decel. I have stock airbox and HD mufflers with no crossover. I think the muffs caused some more popping than normal. I also have the pilots out more than the average number I see around here for XS bikes, can't remember what it is though. Helped with the popping, but performance at low rpm's??? I dunno, I didn't really have any stu uttertutter stuttering problems. Hope it works for you.

Getting the carbs in and out, oh ya, that's a PITA, no way around it. I usually tilt them down towards the front and work the cable attachement linkage past the carb boots one at a time. Then pull back and up into the air cleaner boots, then push forward into the carb boots. I usually get a 3.5 out of 10 for execution, and 10 out of 10 for interpretive language style!

[TopCatGr58]

Yeah, I guess that if we want the stock look we'll have to live with the tight quarters. Where can you get the airfilters for the stock box???.

Hey Cobia,

The stock filter is still available on BikeBandit for only $53.00!!!
You can check the Yamaha site for the OEM part number, and search other places, including your local dealer, but have not seen any aftermarket ones due to their rarity and demand, so few XJ11's made vs. the other years!

There was a thread, I think it was made into a tech tip, but can't remember for sure, about how to make your own out of a K&N filter, that way you can re-clean it!! The previously banned Maximan had posted that thread, but the photos got OFF Site De-linked before they could be saved. Perhaps someone saved them and could post them for you?
T.C.

Okay found the thread, here it is:
http://www.xs11.com/forum/showthread...26N+air+filter

[Cobia]

More on the carbs....

Cruiser and Yadada,
We (BikerPhil and I) started out with floats at 23 since they are the same series 3 carbs as on my '80G, where they ran super, and bench synched them as close as we could. And then tried to synch them on the bike, but in the absence of a YICS tool it was pretty much fruitless. It ran crappy eventhough we kept backing out the idle mixture screws to improve performance. Carbs came back out and floats adjusted to 21.5 due to obvious lean condition as evidenced by the color of the plugs. Ran a little better but not what it should be.
Then I built a YICS tool using the blueprint provided by Ken Talbot, he also kindly sent me a piece of high temp hose for the compression glands. After a synch attempt with the tool, Carbs came back out and floats dropped to 20.5and synched with the tool in place. It made it run better but still not where it should be.
Then I bought and installed the YICS Eliminator and when I put it in, it ran like total crap. So I took it out and waited for BikerPhil to come up with his synch tool so we could install the Eliminator and synch it again properly, big difference! We got it real close, and way better that with the YICS tool but still not where it should be. There is still that hesitation in the RPM range I mentioned (1.4K to 2.5K) where it just sputters. And this is the range where you are basically idling or progressing slowly say like in a neighborhood or a parking lot!! And I'm still getting popping on decel and warm up!! And the plugs are still white. I checked fuel flow so I don't think that's it, if it were it would starve for fuel in the high RPM range.... Unless I have a vacuum leak that only affects the lower range??? Will check the vacumm hoses next and then just order the pilots and mains.

TC,
"only $53.00"...... geezz!!
I wonder if there's a Canadian source for these filters since they sold the XJs for another couple of years up there????
Thanks for the research on the thread, I appreciate it. Might be arm-twisted into that mod 'cause I don't much care for the pods either, frequent rains in FL and all....
Thanks All, I'll keep you posted as to the results of this tinkering.