What jet size do I need?

[Tusler]

Hi,
I recently got an 80 XS1100SG and I put in new carb kits to get the float systems working right. I am putting individual air filters on each carb, will I need to re-jet or will the stock jets be ok.
This thing rides very nice, and has a tremendous amount of torque at least it feels like a lot more than my old KZ1000. I notice at low speed the front end feels very heavy in slow turn, like making a U turn in a neighborhood street- is that normal?

[psycoreefer]

Yes you will probably need to rejet when you go to the individual filters - especially if you have a non-stock exhaust system like a 4 to 1. You can find some recommended starting points here.

As for feeling very heavy in slow turns I can't help you. I know when I got mine it felt heavy but then again it is twice the weight of my old bike, after a week I got used to the difference and don't notice the extra bulk anymore, even when switching back and forth between the lighter bike and my XS.

[dbeardslee]

Heavy in slow turns

Can't remember where I got this tip, but it works for very slow u-turns. Hold the engine at 2500 rpms, sit up real straight, and control your speed with the clutch and foot brake. Don't lean, steer. The engine will act like a gyro stabilizer. Using this technique I can make a u-turn in the width of 2 parking spaces. As far as it feeling heavy - at 560 pounds it is heavy!

[geniusloerts]

check your front tire air pressure

[81xsproject]

Before we can really make jetting recommendations we need to know how your carbs are jetted now and if your carbs use the rubber plugs on the pilot tubes.

[BrianB]

When I got my bike it felt like that too. Put the bike on its center stand and place a jack under the engine mount and raise the front wheel up off the ground. The steering should be smooth with no notchy feelings. Mine was tight and I replaced the bearings. Makes a world of difference especially on u-turns and slow speed handling.

[Tusler]

Hi,
Thanks for the responses. My front tire was a little low so I fixed that.

These carbs are all stock I think?
The main jet is 110 and the smaller one is a 42.

I don't even know what you are referring to about the rubber plugs.

The exhaust is stock. I like carbs in synch and I check them often, that is why I am going to individual air filters. Taking that big single thing off is to much hassle.
Thanks

[petejw]

before u rejet,
put the pod filters on and take the bike
for a good ride using all throttle positions,
if the bike runs well, leave it
if the bike pings or is flat on acceleration, u mite b able to get away raising the fuel level by a mm or 2, id leave rejetting
as a last resort.

[geniusloerts]

*fuel float level height*

[Bigleo]

The heavy steering at low speed, in my opinion, is caused by the way the axle is placed ahead of the fork tubes on the Special. This gives great stability at speed, but causes heavy steering at low speeds. You can see why if you turn the steering lock to lock. The bike rises as you turn the steering, you are having to lift the bike which requires quite a bit of effort. Secondly the stock buck horn bars are not conducive to applying a lot of steering torque. After I ditched my stock bars and put on a straighter superbike type bar, I noticed a huge difference in low speed controlability. I now wish I had done it years sooner.
Leo

[81xsproject]

If you have stock exhaust or a comparable 4-2 I would recommend going up to 112.5 or 115 mains, and leave the pilot alone.

[Tusler]

Thanks for the help

Hi
I found a store in San Bernardino that has the jets so I got the sizes all the way up to 117.5, they were cheap.
I would rather work from jets than float height - it's easier to change a jet. The floats I prefer to set exactly to the manufacture spec's. It's real hot out here so I would rather run the engine just a tad rich instead of lean. I get my air filters tomorrow so I can finish the tuning stuff and start ride testing and get it tweaked for comfort. I got a clymer manual today and it is sooo much better than the OEM service manual.
Well thanks again, I got to go get in line now for the midnight showing of Hellboy II.

[81xsproject]

You still have yet to clue us in on your exhaust (crucial). I agree on keeping your floats at the spec height. If you got them cheap the probably aren't genuine Miki's. I always recommend going with genuine Mikuni jets as it leaves ZERO questions when re-jetting.

[Tusler]

Hi,
81xsproject, in my second post on this thread I put that I have stock exhaust, sorry that I did not make it clear.
I got the jets from the Yamaha store and they are round and look exactly like the original jets that were in it.
Got new plugs for it too!.

[Tusler]

Success! We can close this one

Thanks for taking the time to help me.
I wound up with 117.5 main jets and 42 pilots. Its running just a hair toward rich which is what I wanted. It pulls steady all the way through the gears with not a sputter. Now I just have to get a license again. I forgot how good the wind in your face feels (June bugs suck though )

I have one of those synchronizers you get from JC Whitney , it does 1 carb at a time using vacuum and has a number scale on it, if someone needs to use it I will be glad to loan it.

Life is Good!