Want to get bigger carbs...need suggestions.

[NorCoaster]

Just as the title implies...I'm looking for something bigger than the 34s...or maybe just larger jets? Am gonna be swapping an 850 FD on along with putting on pod filters this summer and would like to be able to get more fuel to spin that FD a little quicker. Also, I'm planning on doing the 2nd gear mod and want to throw a big bore kit in her too within the next year or two...my end goal is to be able to hit 150+mph...

[jetmechmarty]

Uh.....

What you're saying is that you want to waste a bunch of money on a lost cause. Search the forum, and good luck!

Peace

[motoman]

Uh.....

What you're saying is that you want to waste a bunch of money on a lost cause. Search the forum, and good luck!

Peace

A big +1!......but who knows, maybe he'll figure that out before too much waste is thrown out there.
Could just throw him a bit of a clue and leave out the proven proof, such as for starters, 150mph aint' happenin.

[Bonz]

150 mph plus, XS1100? With that said, if it was possible what road are you going to do that on? Make sure you let me know so I am off of it to avoid the Flexi flyer chassis headshaking its way to oblivion.

Do I read it right, you are asking if using larger jets somehow would equate to larger carburetors?

The way you have stated the post makes me, with respect, ask if you may have the understanding of things in order to try and pull this off.

In any case, as JetMech said, search terms just like the wording you put in the first post. You'll turn up lots of stuff.

The reality is the XS1100 does not "hop up" appreciably. All manner of improvement has been tried in 39 years of existence.

[DiverRay]

...my end goal is to be able to hit 150+mph...

OK, it IS possible, but NOT probable to hit 150 on these bikes. The 850 FD mod will get you close, IF you can hit redline in 5th gear.
I'm just getting ready to start putting together my '78 engine. It has the big Wiesco kit, 1192cc IIRC, as well as the head and new valves. I also have the crank and rods that have been worked on from A.P.E. in SoCal, to the tune of $850 a few years ago! It is balanced to 14K RPM's, but with all that, I'll still need fuel injection and a turbo to hit 150. So yeah, it can be done but just how much time and money do you want to throw at it.

[MPittma100]

Carbs + a lot more

You would need in the area of 165-185 horsepower to start with. And about 10-12k RPM with the math of the final gear ratio in 5th gear. Get that and you will make your goal.

May want to look at something in the area of a K1200 GT or the likes.

[Rasputin]

One of my bikes will hit 135MPH according to it's speedometer (and I am not sure it is trustworthy). I highly doubt that even with the rear change anyone will hit the 150MPH mark without it being towed by a top fuel dragster.
Something like (but probably not in this case) Wallace racing calculators would be able to show you how insane this could be. You would have to enter all the info from volumetric efficiency to tire size to figure it out
Basically if you want to invest enough to do this, show us the math that it can indeed be done. Then hope to god you are able enough to handle the bike at that speed. Trust me at 135MPH that bike is unstable to say the least. It is getting better with new suspension and the TKAT fork brace helped as well as every bearing being replaced.
Yes you can do every mod known and turbo it etc, but at what cost? Far better off to buy the bike that does what you want than to modify one of these enough to even try.
Make sure your insurance is paid up to date and your brakes are in perfect shape. Also please take a change of underwear with you!

[skids]

Horsepower is torque x rpms x a constant. I could be wrong, but it seems that the gearbox change requires more torque and therefore the upper rpms are compromised because there is only so much HP available. I seemed to get more zip out of the bike from the stock gearbox. Turbo. That is the answer. It works for my F150. Honestly, the gearbox change is more of a comfort thing while on the interstate.

[donebysunday]

That's fast

NITROUS !
YES that should give you a laugh even if you don’t make 150MPH., you don’t care if it hurts it's just so damn funny.

[BA80]

Food for thought, larger carbs won't make the intake ports, intake valves, exhaust valves, or exhaust ports any larger.

Picture an hour glass.

The Jap engineers have already squeezed nearly 100 HP from a 68ci carbureted engine. Without FI and turbocharging I'm pretty sure that's about topped out.

I have a friend who spent thousands of dollars on porting, polishing, cams and other mods on one of these engines and only pulled around 20 extra hp.

[skids]

There is the issue of red line due to valves "floating" and a lot of other parts that were designed with working stresses. There are xs11 drag bike out there however...

[Bonz]

Where is the OP? Sorry if I scared him off with my post.

[motoman]

Where is the OP? Sorry if I scared him off with my post.

........Boo!