FCR39 MX Help Please

I have a 2009 DRZ400sm with a MRD/SSW exhaust,3x3, and just installed the fcr39mx kit from TT. I did the o-ring mod aswell. I did forget to order the extended fuel screw so that wont be here until sometime next week.

The carb swap was a breeze and the bike started right up. I followed the directions for the initial tunning. After my first ride I noticed a slight bog with the initial take off with light throttle. I also noticed on decel the popping from the exhaust was bad.

So I took it apart again(really wish i had the extended screw at this point) and from the mixture screw being 2 turns i turn it out to almost 3 turns. The bog got alittle better and so did the popping on decel but both are still there.

I know some popping is normal but this is more then I had with the stock carb w/JD kit. I did not have the bog as well. I know this is a sign of being on the lean side. Just wanted some help on what to change or adjust to help smooth it out.

The WOT does feel great and is a big inprovement over the stock jetted carb. But I know there is more in the set up and with alittle help I can get the most out of it.

I am at sea level btw.

Thanks in advance for any help!

try adjusting your squirt timming , a 1/4 turn out at a time . adjust test adjust

remember the first setting so if no improvment or gets worse you can go back

Thanks for a quick response. But I'm new to the bike carb thing. All my other bike were fi. I can rebuild a car carb with my eyes closed. Can someone explain to me which screw is the sqirt timing screw. Thanks!

What jetting did you use? EMN.

Thanks for a quick response. But I'm new to the bike carb thing. All my other bike were fi. I can rebuild a car carb with my eyes closed. Can someone explain to me which screw is the sqirt timing screw. Thanks!

When you did the O-ring mod... you pulled it over a little arm with a screw in it. That screw controls the timing on the accelerator pump. Turn it in 1/2 a turn, and see if the bog gets better. I'm not using the TT kit FCR39... but I turned my screw in an extra 1 1/2 turns from where the last bike liked it... and my bog is non-existent.

I'll add, the popping is normal for a non-cv type carb without a coast enricher.

You should set the fuel screw for the best idle and leave it be. Do not try and adjust it to affect a problem that it is not intended for. Fuel screw is for idle only!

I used the jetting that the carb came with and the emn needle. I will try the sqirt screw today and see what happens. Once the extended scree gets here I can set that better. Thanks again

Ok the part throttle bog is basically gone. But I had to turn the mixture screw back in a 1/2 turn because the bike was dieing at idle with it being 3 turns out. But the popping on decel was better.

Now that the mixture screw is 2 1/2 turns out the bike idles fine but the popping got worse again. Is there a way to help this or should I just get used to it with the fcr and mrd exhaust?

Get used to it. Popping is a fact of life with an open pipe.

killa 09 drz show some pics of your bike the guys here would love to peep it,...

Will have some pics up this weekend. As you know NYC weather sux the last few days.

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