2 different jettings/2 different bikes...?

[xs11bobber]

It seems like a majority either has the stock airbox with a stock exhaust, or pods with a 4/1. I'm getting ready to order jets now.

What size pilots and mains for each bike:

79SF, 4/1 w/airbox?

79SF, 4/2 open header, no baffle, w/turnouts w/pods?

[XJOK2PLAY]

XS11.com Forums > Maintenance > Carburetors
Carburetor Facts - Models and Jetting


Maybe this will tell you what you're looking for...

[xs11bobber]

Carburetor Facts - Models and Jetting

I don't see it??? It just shows stock jettings

[XJOK2PLAY]

My bad....
I see now what you're asking...
what jets for mods, in other words?

Smarter carb gurus than I here... but sometimes you have to go trial and error. Each engine's different, and altitude, all that can effect it.

I know you can buy jets a lot cheaper individually, but... I will say this...

I had a few minor carb issues, and after 2 of my friends going w/ a Dynojet kit and seeing big improvements in both rideability and MPG's I decided to go that way on my XJ this weekend.

Kit comes set up for 2 different apps.. Stage 1 stock or Stage 3 modified.

You would need to go Stage 3, sounds like. Good kit, but pricey.
Unless you find a deal somewhere... mine was $138
But, both buddies were getting low 30's before, now low 40's... that's a mod that not only pays for itself in time, but extends the riding pleasure!
Hoping I see the same results... mine got 32 @ best. Time will tell if it was a good or bad financial investment...
Only took a couple of hours to install...

[xs11bobber]

hmmm...
enlighten me. I'm doing nothing right now but blowing $$$ on parts right now anyway. Bikebandit, partsnmore, and mikesxs have all recieved small lumps of cash from me tonight. Where can I find out more about this dynojet kit? $138 doesn't sound bad and seems like it'll pay for itself. I've heard of the dial-a-jet kit. Is it anything like that?

[MrOzz]

Call some local MC shops you might get lucky. I found one for $80.00.

You can find them on ebay also.

http://cgi.ebay.com/ebaymotors/80-83-Yamaha-XS1100-Dynojet-carb-jet-kit-stg-1-3_W0QQcmdZViewItemQQ_trksidZp3286Q2ec0Q2em14QQhashZitem5186b8d6feQQitemZ350152611582QQptZMotorcyclesQ5fPartsQ5fAccessories

Good luck,
Ozz

[xs11bobber]

The dynojet is pretty interesting and I might go for it someday, probably sooner than later at that, but ordering jets now...

From what I've read in the past 10 minutes... 147.5 mains and stock pilots will work ok on my bobber with the pods and 4/2. Does this sound correct? ...and... an... extra... turn on the air mixture screw???

Then I'm thinking stock mains and jets will work ok with the 4/1 w/airbox but I'm gonna try reading some more...

[bikerphil]

I'm thinking stock mains and jets will work ok with the 4/1 w/airbox

You should have no problem that way, I ran mine set up like that for years. In the hunt for more power, I went to 45 pilots and 142.5 mains (78-79 type carbs).

[TopCatGr58]

Hey Bobber,

Did you see this jetting mods "GUIDE" in the MODS forum??

But as was stated, you may have to try a variety close to the guide sizes to find the right size!
T.C.

[DiverRay]

Bobber,
With the 4/1 + airbox, I'd use 145 mains, and turn the idle mixture screws out as needed( see the tech tip,( http://www.xs11.com/forum/showthread.php?t=13124 ). For the bike with the open system, I'd go with the 147.5 mains, and 45 pilot jets. My choice for jets is mikesxs.com. They fit, they are cheap, and he ships quickly. He sells most jets in pairs, because they are for the "650", but just order two of each. I do NOT remember the exact pilots you need, but I think they are the "early" type. I know the mains are the "big head" early type.

[XJOK2PLAY]

hmmm...
enlighten me. I'm doing nothing right now but blowing $$$ on parts right now anyway. Bikebandit, partsnmore, and mikesxs have all recieved small lumps of cash from me tonight. Where can I find out more about this dynojet kit? $138 doesn't sound bad and seems like it'll pay for itself. I've heard of the dial-a-jet kit. Is it anything like that?

Josh,
I checked 3 bike shops around the Tulsa area, including a tip I got about a local bike salvage... (they could order one.) Then, called the local Yamaha dealer in Stillwater where my friend lives that helped me install it.
Surprisingly, they were all the same price, regardless. They all could have ordered it for me, so it's widely available.

(Not sure about "Dial-a-jet"...)

I remember a few days ago when Ozz posted that he scored one for $80 !
(That was a great price... mine ended up being $125 + tax.)

Took 3 days for the order to come in... no hassels.

Very easy to install, comes w/ good directions & everything you need to do the job. Even if you have only been around these carbs for a short time, if you can read & follow directions, you can do it...piece of cake.

It was easier to install the kit than it was to pull / reinstall the carbs w/ my stock airbox and adjust everything back out and recheck the synch, (which isn't that tough!)

You just have to be careful with the little "c" clips... but the guys at Dynojet are thoughtful enough to include new extras for us guys w/ "large hands"...(ahem...) DAMHIK

The new needles that come w/ the kit are longer, and tapered differently... and I believe therein is the hidden recipe that makes the kit a winner.
For all the washers many here have tried to add to "drop the needles a bit",
the multitude of times of pulling and reinstalling the carbs, trial & error... these folks seem to have done their homework.

I've only been able to put about 20 miles on her since Sat... (Rain)
but I could tell an immediate increase in torque across the whole rpm band! Pulls like a screamin' banshee now! ( I thought it pulled pretty good before, but- WOW!)

My plugs showed I was lean before, and it was popping @ idle and on decel. This fattens up the jets, changes the needle taper & length, which changes everything. I hear when you're too lean in some areas & too fat in others due to worn jets / needle jets... that's where the fuel economy goes... even though this kit increases jet size a lot, it gets it right somehow, which improves economy... pretty wild, but makes sense if you really think about it.
The jets wear from the needle sliding in/out, which messes w/ the mixture.

80's mag ads I've seen that listed stats on the 11's claimed low 40's when they were new, and there are several guys who say they get that or better on here. But not sure what all they may have done for their's to get that mileage.

I personally witnessed my buddies' bikes improve by riding with them before & after. They both gained 10 mpg. One was a Special, the other a Standard. So now, we'll see about the XJ. Mine's best was 32.

XJ's have the smallest of all the jet sizes anyway... but this is way better than just swapping to bigger jets... thanks to the different needles!
If nothing else, it eliminated the popping in the exhaust, and sure pulls harder.

Still dealing w/ some idle return speed issues... (may be a seperate problem, since it was doing the same before the kit...) but so far, I can tell a big difference. If my fuel mileage also improves, it'll be most XSive!

Now... my salespitch for Dynojet is over...
And no...this was not a paid promotional ad by a famous actor...

I plan to post mileage results later on when I have the facts... acquired the "fun" way!

[xs11bobber]

Wow. Thanks for all that great information guys. In all my searches I didn't find anything like that... maybe twas the operator. The "jetting recommendations' forum figures me at needing 150's for my bobber. 147.5's should get me started I figure. You sold me on the dynojet thing xjoktoplay, lol. You need to work on your Billy Mayes a bit though. I ordered the 147.5s last night along with the rest of my $250 order ...oops. I might take another visit today and just order the 145s and 150s as I already have a new set of 142.5s... (like safe auto) Justin Case