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Discussion Starter · #1 · (Edited)
Good afternoon everyone,

I am in the middle of my FCR install and I cannot get the carbs all the way into the intakes.

There is about a 1/4 to 3/8 inch gap between the intake rubber and the body of the carb.

Is this normal?

Ditto
 

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Ditto,
It's like that on mine. Look at the inside you'll see the carb intake rubber has a lip about 25mm from the outside edge (I'm guessing on the numbers you'll have to measure). Then look at the carb intake spigot and measure it (outside edge to carb body). My guess is the difference is about 1/4".
Also, if you were able to insert it all the way to the carb body would the carb bottoms hit the block?
Did they come with some kind of carb support? I've been running without but I think the rubber intakes are taking their toll!
Searching for pic links I found some interesting links (I was looking for a pic with these carbs installed. It's out there I just couldn't refind it!) EDIT: Last link shows a trip engine with FCRs
https://zrxoa.org/forums/showthread.php?t=178754
http://www.british-customs.com/british-customs-fcr-39mm-carburetors-triumph-motorcycles-pr-1719.html
http://www.alecgore.com/AscotStory.html
Triton
 

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Discussion Starter · #3 ·
Thanks, Triton. Buttoned it all up and have it ready for atest ride (hopefully afterwork). It is dead just off idle, so someadjustment will be needed. I have a feeling I have to adjust the slow air screw, just need to figure which way. I may be ading a Lambda sensor down the road, so I can moniter fuel/air mixture. Reading on it, it is surprisingly easy to do.

I will write more after I ride it.

Ditto
 

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Ditto,
Remember these carbs are different animals than constant velocity carbs. If you whack that throttle open from idle you are going to just bog it out. You have to roll on the throttle to get the rpms up THEN whack a mole! Hahahaha hang on though.
I was told you have to ride the bike a bit different now. Keep it up in the revs (and the power band). Try adjusting your application of throttle before monkeying with anything else.
Triton
 

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Discussion Starter · #5 ·
Thanks for the advice - I will keep that in mind. I used to run an fcr on a micro-sprint, and you are rarely coming off idle when racing. I believe I had the accelerator pump off on that carb, as well (it was 8 years ago, and that notebook of info has long since disappeared).

Hopefully I have more info later today, after I ride it.

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Discussion Starter · #6 ·
Took Benadryl...Too Tired...Can't Ride...

Ditto
 
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