Fj1200-xs1100 carbs

[Brill cafe xs1100]

Hello, i got a set of fj1200 carbs for pennies on the dollar and i was wondering if itd be an advantage to run them, i havent seen a very straight forward answer just seen that its been done by others

[oldyam80sg]

I don't know if those particular carbs will work. I know Kawasaki ZRX carbs will work. I have carbs off a Kawasaki GPZ 1100 I believe that just don't have the K-tric like the ZRX carbs have. My GPZ carbs are sitting in a box in my living room, as I bought them and just got over a medical issue and kept the stock carbs on. I wanted to ride and not play with them. Some topics on the ZRX carbs are on this site.

[cajun31]

Do a search on this site and you will find at least one thread where a member used them. I do know the carbs are BS36 not BS34's. I believe the FJ 1200's also use a push pull cable vs the pull cable the XS1100 employs. Meaning some changes will have to be made. I also think you would have to restrict the vacuum advance because these carbs have no place to hook that up to. Might also have to change the jetting on the carbs as well. It is doable but I am not sure you will get any performance gains from them. Is there any reason you need to replace your original carbs other than just curiosity?

[bikerphil]

IIRC, the spacing of the FJ carb bodies is different and won't line up with our rubber intake manifolds. A quick measurement will tell you.

[oldyam80sg]

ZRX carbs are not just put on and go either. Got to find a way for the throttle cables as stated above.

[DEEBS11]

Even if they line up the jetting challenges aren't worth the effort. Clean, stock carbs are hard to beat.

[DEEBS11]

For those with the funds:

[oldyam80sg]

Even if they line up the jetting challenges aren't worth the effort. Clean, stock carbs are hard to beat.

I got my GPZ 1100 carbs but my 80 SG ran excellent with the stock carbs was the reason why I didn't switch it.

[jetmechmarty]

https://youtu.be/5eUnbVAp8hI?si=YajAeTtBSys5AbEk

[DiverRay]

Deebs, the ebay photo shows KEIKEN carbs, NOT Mikuni! We all know those are NOT factory carbs.

[cajun31]

Deebs, the ebay photo shows KEIKEN carbs, NOT Mikuni! We all know those are NOT factory carbs.

Ray... I believe what Deebs posted are indeed Mikuni RS36 carbs. The video that Marty posted of Andy installing them on his basket case shows the same carbs. The listing that Deebs posted in the actual description say that the carbs have actually been pre-jetted and spaced correctly for the XS1100. I suspect that is why the price is a bit higher than others out there. One other thing that has to be considered if anyone is considering those for their XS1100's is that by default they are push pull cable carbs and in Andy's video he addresses that problem. Here is the actual link to the Ebay listing 1978-1981 Yamaha XS1100 Mikuni Carbs RS36 | eBay.

[Bonz]

Can someone saying the push-pull is an issue, explain the changes that need to be made when putting a single pull cable onto a set of carbs that has push-pull? If it is a problem, how have you solved it? That is more rhetorical than anything.

The push and pull cables have totally different hookup points. Carbs that have push-pull, can ditch the push cable without issue.

The point being, imo, there is a problem being thrown out there that is not an issue unless it's based on specific experience with this setup or any push-pull set of carbs.

Jetting issues are not hard to overcome, unless you don't have experience making jetting changes. And the ZRX carburetors are more modern with respect to their design, they will be an equal or better in performance than stock carburetors from the '70s.

Check out my signature line, although the link doesn't work anymore. Is there a way to harken back to the link that was from the old forum? Yes indeed ZRX carbs are are a good spacing fit. There was a pictorial how to drill a vacuum fitting hole into the ZRX carbs in order to keep the vacuum advance. However without those pictures I sure as heck wouldn't try it.

[cajun31]

No one is this thread said that push pull concerning the FJ1200 carbs was "an issue". I did point out that they are by default push pull and that would have to be addressed when putting them on an xs1100. I have never used them on an XS1100 so I was simply trying to point out to the OP that those carbs by default are a push pull setup. Looking at the schematics on sites like Partzilla isn't much help but if you search and find a set on Ebay you can readily see that they are setup with return springs much like if not exactly like a set of XS1100 carbs. The vacuum advance missing is a bigger issue and like Bonz just pointed out the FJ1200 carbs would have to be drilled / modified if you wanted to keep it. When Deebs posted the RS36 information I went on to point out that those carbs are indeed push pull and won't function on the XS1100 without a modification to employ push pull.

[LAB3]

That would just be a different throttle tube and cable pair, wouldn't it?

[Bonz]

Where I'm coming from is the point where it was said some changes have to be made. A user does not have to find a way to make the push pull combo work. The push-pull carburetors work fine with a pull cable, no change needed. Just like the Yamaha stock carbs with a pull only from the get-go. Push-pull carbs work fine without going to those lengths. May need to get the proper length cable to work with the existing throttle tube, if it needs to be changed at all.

The carbs I'm talking about drilling are the ZRX carbs. The thread specifically addressed ZRX carbs that fit perfectly, is there a way to pull that link up that's in my signature from the old forum and recreate it here? It shows the location and angle to drill a hole for a vacuum port on the carburetor.

What I hear you saying cajun31, is the RS36 won't work with a pull only? I believe they have adjustable tension return springs where the push could be left out of the equation. But don't quote me on that.