1100 carbs onto 1200 engine...jet settings

[mr blackstock]

G'day,
I did a little research in the files section, but I could not find the info I was after.  If I was to put carbs with stock 1100 jets onto a 1200 engine, would there be an issue?  I looked over the different jet sizes for each engine size, and it seems the 1200's jets are more restrictive than the 1100's.  Except for the Fuel pilot.
               FJ1100                FJ1200
Main          112.5                  110
Air pilot      160                    155
Fuel pilot     37.5                  42.5

Are there benefits in leaving the 1100's jets in place for the 1200 engine?  Are the 1200's more restrictive due to emissions?  Am I reading things wrong...
any advice?

Cheers, Gareth

[FJmonkey]

The jetting for the 1100 should be fine as long as you still have both the air box and stock pipes. My 1200 idled better and needed less choke with #40 pilots. You may have an issue if you put 1100 carbs on a fuel pump 1200. They can be converted over, Randy has the parts you need to switch from Gravity Feed to Fuel Pump (or the reverse).

[mr blackstock]

G'day,
Thanks for that.  I will stick with what I have got, any issues I suppose I can buy some jets later on.

cheers, Gareth

[Arnie]

Gareth,

From the numbers you posted, the 1100 carbs are slightly richer than the 1200 carbs except on the idle circuit.
As the FJ1100 was marketed as a "performance bike" and since that was before the California and the US took much notice of bike exhaust pollution, its probably a better jetting than the 110 MJs of the later bikes.
And, since the carb slides were different on the earlier bikes (1100s) the slide difference may have effected the mixture strength at idle enough differently that the seemingly leaner jetting was still "right".

And, since the 1100s were gravity fed carbs as were the 1200s up until the '89 model, you don't need to concern yourself with changing the fuel feed or the float needle jets.

Once you have the newer carbs mounted you may still want to change the jetting, but there's no need to be overly worried it'll be out by much.

Arnie

[mr blackstock]

G'day Arnie,
Good to hear I was not barking up the wrong tree.  I went out and bought a FJ1200 motor, the one with 16000kms on it recently listed on ebay.  I cannot wait to bolt her in, fire her up and then make a booking for the rally.  I checked out the seller, went and met him, and was happy that he seemed kosher.  Proof is in the pudding though...

cheers, Gareth

[krusty]

  Proof is in the pudding though...

Not quite so. You have the pudding(bike). The proof is in the eating (riding).

Often misquoted, it's, "The proof of the pudding is in the eating"