count to eleven (stuck at 7)

[sxigh]

Hey guys, am on my first eleven here, a purty '78E that I picked up from a guy in Baraboo, WI (www.wisinois.org/files/xs11.jpg) and have just disassembled the carbs to find a couple things amiss.

Aside from stripped screws on the outer body, air jet #1 is sheared completely, a pilot jet is getting there, and my mixture screws are slightly bent at the tips. I wanted to ask y'all how much this affects performance, and if I could get part #48-5011 (http://www.mikesxs.com/mikesxs-fuel_...ategory_id=4.4) from mikesxs.com to safely replace the stock screws. I'm aware that he carries our pilot jets, but anything else? I also need mains (142.5) so I can run my k&n in the airbox w/ the kerker 4-1 pipes.

Brand new pipes which are badly blued now, btw. Didn't realize til later, but I got the bike with the idle screw at 3 turns out and bp8es plugs and needle clip down one. bp6es plugs, new mains, a synch & a colortune should set everything straight.

I'm looking for a reputable source that can ship me these parts in short notice. Motorcyclecarbs.com can't do it for 10-14 days.. It's too nice not to ride!

Cheers,
>Dan

[DiverRay]

Dan,
mikexs parts will work. check the tips on the left side of the page, or do a "search" on carbs. If you order from mikes, DO NOT tell him it's for an 1100. let him think it's for one or two 650's, as that is what he sells the parts for. He may not want to send you parts if he thinks it's going on an 1100.
Ray

[sxigh]

Thanks Ray, I thought the parts were interchangable from the looks of them. Does anyone know where to get air jets for a good price? Motorcyclecarbs.com wants to charge 7 bucks to ship this little piece of (br)ass.
>D

[DiverRay]

I have NOT replaced any jets on my carbs, other than a rejet. I would just clean all the jets, and reuse them. If you need to change jet size, get ONLY OEM jets. DO NOT use K&L jets in your bike!!
If you go to the Yamaha site, you can compare part numbers for the jets on the 650 and 1100. I would just order anything you need for the carbs from one place, so the shipping is cheap.
Ray

[sxigh]

so I managed to find some mains at this supplier in town, got everything dialed in minus the synch. bike runs pretty tight for a few miles until the #1 plug fouls up. I'm gonna take this as a problem caused by the stripped air jet due to a shaving coming loose and blocking the flow.


Can anyone tell me where the air travels through this orfice so I can clean this passageway?

I also need to know what the mikuni part number is for these jets. Closest I can find from their catalog is the nbr BS42/55 but the measurements seem slightly off in comparison between what they spec and what mine actually are.

I love this bike. It's so hard to watch it sit!

[motoman]

A few dabs and some rubbing with Blu-Away will fix the pipes........should be available at any local accessory or bike dealer .......a little pricey at $17 for a botle of the paste...............only thing that works tho...........and don't use chrome polish anywhere there is high heat as this will cause pipes to gradually turn a gold color......

[TopCatGr58]

Air Jets!!

Hey there SXIGH,

Well after much research, like you, I was kinda bewildered about the air jets cause I hadn't had the need to replace mine, and I didn't take them out when I cleaned the carbs, just sprayed thru the hole!!

I was looking at the "Mikuni Air Jets", both the BS30/97 as well as that other size, ??22/45 or such, but both pictures I found did NOT LOOK RIGHT! Our air jets are small round slotted heads with threads below that!?

Then I REREAD the description on MikesXS, see below in BOLD:

Main Jet - Small Round Type
#160 Main Jet - Small Round Type - N102/221 Mikuni type - Fits: 1970-79 Stock
XS650 Mikuni BS38 CV carbs and also used as the Air Jet on 1980-84 XS650
Mikuni BS34 CV carbs. Sold in 2's.


Part #48-0224 $6.00 USD /Pk./2

And the above picture looks EXACTLY what the air jet that I just took out of a set of 81 carbs I had, and it will also fit into the hole on a 79 carb body I had!!

So....I learned something today! The small round head "main" jets series N102/221 are ALSO the AIR JETS for our carbs! That will make finding and buying them easier!

Regrettably, MikesXS only carries them up to 160 size, and the one I took out was a 185! BikeBandit DOES carry them!!

And in the photo below, part "a" is the Air Jet, another view!
T.C.

[sxigh]

hey topcat, thanks for that reply. I've been through all the information on this site regarding carbs & jets, but my jets look much different from the small round type and I need a 210 size. my jets look much closer to http://www.motorcyclecarbs.com/image...ets/b42-55.jpg and this is the bs42/55 type only the dimensions were a little bit different when I looked through the catalog that the kawasaki dealer in town had. Maybe I should just order one and see if it fits, a couple bucks are no skin off my back...

[sxigh]

urggg.. 219 views and nobody can answer where the air travels after the air jet?

from previous post:

"...bike runs pretty tight for a few miles until the #1 plug fouls up. I'm gonna take this as a problem caused by the stripped air jet due to a shaving coming loose and blocking the flow.

Can anyone tell me where the air travels through this orfice so I can clean this passageway?"

ideas, pretty please..

[TopCatGr58]

Carb Diagram!

Hey SXIGH,

Here's one that was drawn up, I think it's for the later 80-81 series carbs but should provide some help?


T.C.

[red bandit]

The air jet connects to the pilot jet, witch connects to the idle mixture screw. Take the air jet and the pilot jet out and blow air thru the pilot jet and it should blow out the chip. Might have to blow air and use a small pick at the same time. Good luck.

[sxigh]

heck, that's a real post. think about how much that diagram's going to help others understand how the carburetor works. this deserves to be in the tech tips, methinks. now, if only I could get access to an air compressor again and blow that sucker out.... looks like any shaving significantly large enough to run the bike that rich couldn't go any further than the main jet and is probably just stuck near the emulsion tube.

[pggg]

About the PILOT AIR JETS (different than the MAIN AIR JETS which are pressed in and have a tiny hole) - they're simply called BS type PILOT AIR JETS(mikuni). You can change 185's to 210's by running a 5/64ths drill bit thru from the threaded end. The SMALL ROUND type main jets are different as they have a funnelled exit hole unlike the stock XS11 PILOT AIR JETS. Whether that makes a noticible difference, who knows, but the stock PILOT AIR JETS are as readily available as any other mikuni jet.

[sxigh]

no kidding, I just noticed that. I was calling around about air jets all week and they've been askin me main or pilot when I've been haggling about just plain air jets ..

btw, I sprung for a colortune & just checked out the pots today. 2-4 are blue, #1 doesn't fire at ALL! pull the choke out and she fires blue, but with the choke in, I'm not even getting ignition. maybe that's a really big shaving. any reason to suspect this is attributable to a different problem? spark looks fine, so what else..

[Pat Kelly]

I ad the same thing (almost) n my E. Cylinder #3 had no spark until 4200RPM. The pilot jet was bad. I swapped the bad jet with cylinder #4 and the problem followed. New pilots, no more problem.
Granted with the bike runing on 3 cylinders made for a rumbly idle yet when the carbs transitioned frm pilots to main jets at4200RPM there was a substantial kick in the pants.
Colortune uncovered this problem.