RB Designs and FRP

Tedh98 · Post by **Tedh98** » 04:43 pm Sep 03 2014

KDX_Johnny wrote:yeah.... she wont run with the 152.5.... and if i do get her to start it sounds SCARY i can either put it back to stock (50/160) or run the 42 with the 160....

The main jet shouldn't impact the starting of the bike. The MJ is primarily WOT.

KDX_Johnny · Post by **KDX_Johnny** » 04:50 pm Sep 03 2014

idk what to say unless im a complete freakin idiot and have the wrong jet... because they dont look the same at all. one looks like a flat head screw and the other looks like a long hex head bolt. the hex head one is a lot longer on length... do i have the wrong type of jet?

Tedh98 · Post by **Tedh98** » 04:56 pm Sep 03 2014

The MJ is the hex head one and the PJ is the one with for the flat head.

As Julien mentioned, you start with the pilot circuit, then needle and finally the main.

When you said you "did the first part", I interpreted that as you did the jetting for the pilot circuit. Is that correct, or did you go on to do the needle and main?

KDX_Johnny · Post by **KDX_Johnny** » 04:59 pm Sep 03 2014

pilot circuit. and i guess i have to buy a hex 155 and a hex 152.5 tomorrow then...

Tedh98 · Post by **Tedh98** » 05:03 pm Sep 03 2014

KDX_Johnny wrote:She doesnt want to start for nobody right now... right now its 42PJ 152.5MJ and 3 turns out on the pilot mixture screw... idk guys ill get her to run for maybe 10 seconds but she sounds WICKED and bogged when i hit the throttle and revs when i release it. not a clue...

So 3 turns out got you the highest idle? At that many turns out your PJ is too big.

KDX_Johnny · Post by **KDX_Johnny** » 05:14 pm Sep 03 2014

No no no. Okay let me restart. My apologies. I restarted the whole process with a 42PJ and a 160MJ. I ran the Pilot circuit. After adjusting the idle I was at exactly 2.5 turns. (The max) I turned off the bike. I ran the 0- 1/4 throttle runs and went in 1 1/8 turns and I got a FAT CRISP throttle response. So the air screw is sitting at 1 3/8 currently. I re adjusted the idle to my preference. I still have that nice fat pull. I took the bike out on the road. It feels a tad weak in the mid range.. My guess is because the 160 is just too much gas. I already know if I run the 1-6 gear pull my plug will surely be black. So I tried to skip that step and put the 152.5 in and test. But it won't start with the 152.5... My guess again is that I DO NOT have the correct jet. I will go back tomorrow and buy a 150 hex, a 152.5 hex and a 155 hex. Because like you said there should be no reason for the bike NOT to start.

Tedh98 · Post by **Tedh98** » 05:37 pm Sep 03 2014

KDX_Johnny wrote:Because like you said there should be no reason for the bike NOT to start.

That should be correct as the main jet primarily controls WOT. What happens if you put your 160 back in with your current PJ and AS settings?

The next thing to set-up is your needle, that would impact your mid-range.

KDX_Johnny · Post by **KDX_Johnny** » 05:46 pm Sep 03 2014

The bike is running very well with the 160 in the carb with my PJ and AS adjustments. It just lacks the mid range bite. Which you said can be adjusted by the needle. How would I be able to do that? Which jet is the needle jet? I get a little confused when I'm looking at the inside of this thing because I only see the MJ and the PJ. And does the MJ effect my top end?

KDX_Johnny · Post by **KDX_Johnny** » 05:54 pm Sep 03 2014

I'm going to the shop as we speak to grab a 150, 152, and a 155. I'll start with the 155.

Tedh98 · Post by **Tedh98** » 06:07 pm Sep 03 2014

The needle is the long, tapered brass rod that fits inside the slide.

KDX_Johnny · Post by **KDX_Johnny** » 06:21 pm Sep 03 2014

ohhhhhh okay so i have to unscrew the top to reveal that. if i move that up will it benefit my mid range? Also i got the 150, 152, and 155. ill toss the 155 in because the bike is actually accelerating really quick with the 42PL and the 160MJ

KDX_Johnny · Post by **KDX_Johnny** » 06:43 pm Sep 03 2014

Should I move the clip up for less fuel so I get the mid range power? Or move the clip down to let more fuel in the get the mid range power?

KDX_Johnny · Post by **KDX_Johnny** » 07:52 pm Sep 03 2014

Update! PJ 42 MJ 155 Needle 1174 in second clip..... HOLY HELL! pulls up in second with no hesitation whatsoever and a little lean back in 3rd and its up! Bottom is strong! Mid range is stronger! and im shifting out of gear before i hit the top so i like it how it is maybe when i get the pipe ill down size on the main but i love it! Now my only question is that the bike sounds a little... zippy? i guess is the word to use. Should i be worried? doesnt that mean im lean?

Post by **Julien D** » 09:06 am Sep 04 2014

Without doing plug chops on the main there's no way to be sure. Being a little lean on the pilot or needle isn't likely to cause any harm, but a lean main jet can ruin things pretty quickly. With a 155 in there it shouldn't be a problem though.

KDX_Johnny · Post by **KDX_Johnny** » 10:36 am Sep 04 2014

Sweet thanks! Then I'm keeping it! She's running great! It even starts up smoother, idles smoother, warns up faster. The whole bike is just... Smooth... And so much more snap than I ever had. Thank you everybody for the help! I am extremely happy. Sorry for being a pain in the A**, but thanks for sticking with me! Haha I'll be sure to post an update when I slap the pipe on! Have a great day everybody!

KDX_Johnny · Post by **KDX_Johnny** » 08:17 am Sep 12 2014

DID IT! Full exhaust is on and it sounds great! Bottom end is full of life! plenty more than i need which makes me happy i went with the desert pipe. A little less top end than i wanted... but i guess you cant make an engine do was it wasn't built to do! hahaha. In my curiosity the FMF chart says use a 45PJ and 155MJ with an 1173 needle. Im running the 42PJ and 152MJ 1174 needle in the 2nd position. Should i move the clip down for a little bit more fuel? because when doing REALLY QUICK half throttle chops (just revving the bike) it sounds like that tiny bog way down low is still there... but when riding the bike with this new pipe it doesnt effect me at all. with all the extra torque it just blows right through that tiny bog way way way down low. but it still rings a bell in my head that says i should fix the tiny rev bog. What would be the better move? 1. Leave it 2. Do the pilot circuit with a 45PJ? or 3. Move the clip back to position 3?

Just for reference Jeff at FRP told me to run stock jetting with an 1173 needle.... so maybe ill buy an 1173 needle and stick it in there also?

I am just looking for some advice! Thanks Guys! Keep on Roostin'!

Post by **scheckaet** » 08:52 am Sep 12 2014

just follow the jetting guide in my sig. sounds like you're close.

KDX_Johnny · Post by **KDX_Johnny** » 01:48 pm Sep 13 2014

Got it again guys! 42PJ 152MJ 1174 needle in the 3rd position. Runs like a raped date! Thanks for all your help!

Tedh98 · Post by **Tedh98** » 03:01 pm Sep 13 2014

Good to hear.

Just wait until you try a CEK or DEK needle.

KDX_Johnny · Post by **KDX_Johnny** » 06:38 pm Sep 14 2014

Where can I get one?

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