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FCR airboot fitment

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I have a FCR mx 39 mm from TT on my 07 sm, Its always a real butthole of a procedure for me to get the airboot/airfilter side of the carb into the DRZ airboot and also get a good seal.  With the TT adapter the engine side always fits snug, but I find the airboot side never wants sit inside the boot snug (typically on the bottom portion), If i dont get the carb perfectly snug there is a slight gap between the bottom of carb and airboot, even when i get it in to the best of my ability and there is no gap between the carb and boot it doesnt seem in there snug and i feel rough terrain may disrupt it off its seal.  Since the carb does not recess into the airboot enough a clamp is not applicable.  Does it sit like this for everyone or am i missing something.  Should i get/make some sort of adapter or extender or just use some tape to bridge/protect the slight/potential gap on bottom?

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I have the same problem.You get two kinds of FCR carbs one with a removable intake bell and one without a removable bell.The latter is a problem.The only thing to do is buy an adaptor-there are guys who manufacture them out of aluminium or a kind of abs plastic-just google drz400sm adaptor.In desperation i fitted a pod air filter on my K9 SM-no more problems and very easy to work on if the carb needs to come off.

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Remove the silencer and lower subframe bolts and swing the sub frame up to the bars. Also helps to remove the RR for more room.

Install carb into intake manifold.

Remove airboot from the box and install on the carb. You will be able to push it on and fully seat it.

Drop the sub frame back down.

Loosen carb from intake manifold and attach air boot to the box

Use a big flat blade or small pry bar to "stretch" the airboot a bit to get the carburetor fully seated back into the manifold.

Sounds like a lot but I can do it faster than I typed all that out.

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1 hour ago, sharkcontrol said:

I have the same problem.You get two kinds of FCR carbs one with a removable intake bell and one without a removable bell.The latter is a problem.The only thing to do is buy an adaptor-there are guys who manufacture them out of aluminium or a kind of abs plastic-just google drz400sm adaptor.In desperation i fitted a pod air filter on my K9 SM-no more problems and very easy to work on if the carb needs to come off.

Jetting would be needed to make up for the extra air of the pod filter, no? Might also suffer if the bike goes into the water etc

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If you have the TT FCR you shouldn't need any adapter.

I install it like this:

1.) Situate the carb lightly in the manifold to hold it

2.) With the filter door off, mash in the air boot with your fist. This helps to push the air boot around the carb, inside, where you couldn't pull it on if you wanted to.

3.) Using a roll pin punch (maybe a 3/16 and make sure it is smooth, not peened over or sharp) insert it between the air boot and the carb at the bottom and slid it upward. This feeds the air boot onto the carb, kind of like a tire lever. Maybe mash the air boot again a time or two to wiggle it on fully.

4.) Tighten the clamp on the air boot to the carb, nice and tight

5.) Push the carb full into the manifold. Again I use a smooth lever, protect the frame and find a solid spot on the carb to lever it forward then tighten the manifold clamp.

The air boot being warm does help. Leave it sitting in the sun or something.

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On 4/11/2017 at 7:53 AM, ohiodrz400sm said:

Remove the silencer and lower subframe bolts and swing the sub frame up to the bars. Also helps to remove the RR for more room.

Install carb into intake manifold.

Remove airboot from the box and install on the carb. You will be able to push it on and fully seat it.

Drop the sub frame back down.

Loosen carb from intake manifold and attach air boot to the box

Use a big flat blade or small pry bar to "stretch" the airboot a bit to get the carburetor fully seated back into the manifold.

Sounds like a lot but I can do it faster than I typed all that out.

So, I just got the TT FCR 39MX kit and the directions were great until I got to the point I had to fix the airbox to the bellmouth. I tried for hours to get them together and got frustrated. On my interwebs searches (including TT) I came across this post and it worked like a charm. The only thing I would add is to put some heat on the airboot/airbox with a space heater. I am stationed at Ft. Drum in upstate NY and it was pretty cold in my garage though, about 17 degrees outside and probably 50 in the garage. You may not need the heat in southern climates or during the summer up here. I picked back up with the TT directions after doing the above process and the bike fired on the first try. Now the ice and snow just needs to leave so I can ride and get the carb dialed in...

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