New FCR from TT not running 100%

I just got a FCR in the last batch from the TT store. I did the install with the one jet removed, 1/4"id 1/16" thickness o-ring, adjustable fuel screw, and jetting for 3x3 and open pipe at sea level. My issues are as follows.

Harder starting on or off choke when cold (what temp should I use choke and when should I just use throttle pumps?) On 4 occasions the bike stalls when snapping the throttle closed after a wot run on the highway. The bike has a flat spot in the mid rpm power delivery. There is a bog when getting on the power after feeling the flat spot. There is a bog when shifting gears while cruising at medium load.

I have tried to double up the thin o-ring but will go on a quest for the thicker ones this week. I have turned the AP screw out 1/4 to 3/8 and don't feel a change. I had the air boot off and watched the AP squirt but I can't see anything as it happens so fast when I snap the throttle.

Mods are 3x3 in the back most airbox top corner, "E" model FMF bomb head pipe and uncorked Yoshi off road slip on. The exhaust is being replaced with the SSW/MRD as soon as it comes.

Any help or suggestions? Turn the ap out more? Get the right o-ring? Get the merge ap spring? Fix the pipe?

What pilot jet?

Bike will almost always need the chole on. In cold temps (under 50) a twist of the wrist can help some prior to cranking. Whan cranking, the throttle sould be fully closed.

Some popping is normal with an open pipe. Regarding the stalling, try increasing the idle speed slightly.

I am using the pilot that was supplied with the carb. I turned the idle up 2 times now and its at the point where I think any more would be too high. I forgot to mention the popping out the exhaust. It is a rythmic POP pause POP pause POP pop pop pop when I let off at high rpm and coast down. The caps pops are loud where the lower case ones would be soft. Don't know how much of that would be normal. A buddy said he saw flames coming out which leads me to believe its rich not lean. I also neglected to mention my elevation is up to 1000ft would that cause issues when jetted for sea level?

So you did not verify you have the correct pilot in. Did you check/set the fuel screw?

Fuel screw settings in the 'book' are recommended starting points. Every bike is different, as is the temp and altitude. Set the screw according to this method.

Gently turn the screw all the way in. Now back it out two turns. Start the bike and fully warm it up, go for a 10 minute ride. Set the idle to speed to 1,500~1,800 RPM as best you can (I know, without a tach this is tough, just set it to were it idles relatively smoothly). Once warmed, slow the idle to the lowest possible speed.

*** When turning the fuel screw, keep an accurate 'count' of the amount you are turning it and record it in case you have to reset it for some reason. Makes life easier when you can just set it from notes Vs. going through the procedure again.***

Turn the screw in until the idle becomes rough or the bike stalls.

if it stalled, open the screw about 1/4 more turn. Restart it and slowly screw it in till you can just perceive a change.

If the screw can be turned all the way in and the bike still idles perfectly and does not stall, then you need to go down a size in pilot jet.

Now very slowly, open the fuel screw till the idle is smooth. Blip the throttle, let the bike return to an idle, wait say ten seconds. Confirm it is the same smooth idle.

If the screw has to be opened more than 3 turns to get a smooth idle, you need to go up a size in pilot jet.

If you find it does not stall with the larger jet but has to be open more than three turns with the smaller pilot jet, put the larger one in and set the fuel screw at 1/2 turn.

If the idle speed increased, adjust the idle speed knob to return the bike to a real slow idle speed. You must then re-visit the fuel screw. Keep doing this till the fuel screw is opened just enough to provide a nice steady idle at the lowest possible RPM. Once this is done, increase the idle speed to the normal one for your bike, typically about 1,800 rpm, but go by the spec in your manual.

The popping sounds normal. Flames too are not uncommon from behind. What happens is when you chop the throttle, the engine goes very lean. The air/fuel charge does not get burnt. Instead it accumukates in the exhaust untill enough is there to be ignited by the hot pipe (pop) So it is not a rich condition, ratehr it is a lean one and considered normal.

1,000 foot is not enough to be a concern.

What year is and when did you purchase your bike?

Ok thank you for the pilot check procedure. I did that with the BRS to confirm that I need the next size up, but will have to redo it for the FCR. My bike is a 06 SM bought new by me. I knew the explination of the popping but didn't think flames were normal. I have seen them in dyno videos but never in real life with the BRS on there. New carb new things happen I guess.

Sluggish starting may be the sign of a weakening battery. I bought my 05 in the fall of 05. The bike appeared to og been prepped during the winter of 04. So my bike sat for nin months. In the end of 07, I had to replace the battery.

So the battery on your bike is at least 3+ years old.

The OEM BSR has a fuel enrichening circuit that on decel, adds a little fuel to the mix to reduce/eliminate the popping.

I upgraded to a ssw super start kit sized battery last year when I was having some aftermarket headlight killing battery issues. It seems to crank at full speed it just seems slow to fire over and catch. I never twist the throttle while cranking as you say. It starts great once warmed up also its just cold starts that take a while. Once running off choke it doesn't like to take throttle for the first minute with out stumbling.

Just wanted to ensure it was not a weak battery issue.

Ok, in this case you might want to bump up the starter jet (stock is a #68) to a $#72. Cold start procedure would be petcock on PRI, wait a few seconds, a few quick twists of the throttle, choke on, and press the button. As soon as it is running, pectock to run, 1 minute later, press the choke in.

Streetfighter , Ive had similar starting issues with my new FCRMX . Sometimes it will not start on the choke , then I have to do the 3 pump and hold the throttle to warm it up method . But most everyday it will fire straight up on full choke no throttle . I am thinking it might be from sitting for a day or two when I dont ride it . As the carb changes the whole feel of the bike , I am just putting it down to getting used to starting a new bike . Mine pops on decel aswell , I like the sound actually . It is a pity to hear of your bogging trouble , mine has none and was great right out of the box , just very lucky I guess , greg :worthy:

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