Jump to content
Sign in to follow this  

Jetting-Exhaust / Where to Start?

Recommended Posts

I've studied the Jetting sticky's but still have a number of questions:

I bought my '06 a couple of years ago and had a smog block-off kit installed and the pilot jet was upsized to a 48 and the air box opened up top only. The bike has appeared to run a little lean at times and got hot on a couple of occasions in elevation and on one other occasion. I'm looking at upping the main jet to either a 165 or 170 to help with the possible lean condition. The bike currently has a 142 main jet in it which I believe is the stock size. It looks like the most widely used Needle Jets are the JD Red, but it doesn't look like they are sold separately, is this correct?

I was going to also get a 45 pilot to have options for further tuning. My assumption is that every bike is a little different and that where you ride is going to have a lot to do with jetting. We ride mostly, mojave desert, baja, and southern Utah with elevations from sea level to 9,000 feet but the higher elevations are generally for a short period as we generally continue through the peaks and head back down.

I'm looking to convert from a stock exhaust to possibly an FMF Q4. I want something a little throatier but not overly loud and will provide a balanced flow of intake/exhaust.

So can I get the JD Red Needle Jet by itself or can I get by using the stock and move the clip and be just as happy. I'm just looking to enhance overall performance of the engine and maintain reliability.

Share this post


Link to post
Share on other sites

JD parts are sold as a kit.

But the Kehien NCVS needle works better anyway IMHO.

165/45/NCVS/50 leak, merge racing apump linkage spring/ then adjust your pump timing.

FMF pipes are inexpensive, and fragile.

ProCircuit T-5 pipes cost more and last forever. Same with Dr D., MRD, Two Brothers, Akrapovic.

Share this post


Link to post
Share on other sites

Krannie,

Glad to see you logged in right now. Perfect, I'm with you up until you talked about adjusting the APump. How is this done? Also, your saying the stock Needle Jet is NCVS which can be left in and just move the clip position correct?

Share this post


Link to post
Share on other sites

How does the Pro Circuit compare to the Two Brothers? I thought I heard somewhere that 2 Brothers was out of business. My neighbor has a 2 Brothers pipe and it sounds crisp but I haven't heard the Pro Circuit. I don't mind spending a little more for something that lasts and outperforms something less expensive. Hell, it's Chrismas and I need to get myself a gift anyway.

Share this post


Link to post
Share on other sites

I just put mine back together 170/45 50 leak jet, merge spring. crfonly AP kit. it ripped before but now it really really runs good. It didn't run bad to begin with but it is my Christmas present to myself. My pipe is stock and gutted and the pink wire is disconnected. I gotta tell ya I am very pleased with this bike. 2005 Boys and their toys

Share this post


Link to post
Share on other sites

Thanks Keith, that's good to know. I was going to gut mine and slap on a 2" exhaust tip I have but thought maybe I'd splurge for a pipe while I'm at it. I'm not sure but would guess that there would be some kind of performance gain with an aftermarket pipe vs. just installing the tip since an afermarket pipe should be engineered better.

Share this post


Link to post
Share on other sites

Thanks Keith, that's good to know. I was going to gut mine and slap on a 2" exhaust tip I have but thought maybe I'd splurge for a pipe while I'm at it. I'm not sure but would guess that there would be some kind of performance gain with an aftermarket pipe vs. just installing the tip since an afermarket pipe should be engineered better.

.... not by much. It's not about more power, it's about better throttle response and putting the power in the rpms where it can be used the most.

Share this post


Link to post
Share on other sites

Krannie,

Also, your saying the stock Needle Jet is NCVS which can be left in and just move the clip position correct?

Stock needle is NOT an NCVS. Order part # 16233-MEN-671. Run it on the 4th clip.

Two Brothers is alive and well. They make an excellent exhaust system, however I agree with Krannie that it's hard to beat the ProCircuit for all around value and performance.

Share this post


Link to post
Share on other sites

Krannie,

Glad to see you logged in right now. Perfect, I'm with you up until you talked about adjusting the APump. How is this done? Also, your saying the stock Needle Jet is NCVS which can be left in and just move the clip position correct?

The NCVS is not the Needle jet, it's the Jet Needle, and it's stock to the R model not the X.

Adjusting the pump is easy.

When you get your jetting done, your merge racing linkage spring installed, and your carb is back on with the subframe lifted up all the way so you can see the inside of the carb intake: you can see it squirt when you twist the throttle (dead engine).

You adjust the timing with the screw under the black throttle wheel cover.

You turn it clockwise to delay the squirt.

The squirt should NEVER hit the slide, BUT no later than just missing it.

Share this post


Link to post
Share on other sites

The PC and Dr. D pipes are also the loudest... by a lot.

That being said the PC pipe does run good.

Share this post


Link to post
Share on other sites

The PC and Dr. D pipes are also the loudest... by a lot.

That being said the PC pipe does run good.

Well, PC makes FIVE different pipes for the X, so you are right, but wrong.

Dr D makes THREE different pipes for the X, with THREE different noise inserts. So again.....

Share this post


Link to post
Share on other sites

Thanks for all of the input. The carb is detached and sitting in the saddle area waiting for the new jets and needle (good clarification on the NCVS Needle / not Needle Jet) and how to adjust the squirt. I may just install the 2" exhaust tip until after Christmas. Will I need to do any fine tuning when I switch over to a new exhaust (slip on)?

Share this post


Link to post
Share on other sites

Thanks for all of the input. The carb is detached and sitting in the saddle area waiting for the new jets and needle (good clarification on the NCVS Needle / not Needle Jet) and how to adjust the squirt. I may just install the 2" exhaust tip until after Christmas. Will I need to do any fine tuning when I switch over to a new exhaust (slip on)?

Probably not. Just the fuel screw.

You should get a R&D remote fuel screw too.

  • Like 1

Share this post


Link to post
Share on other sites

I just put in a CRF's only T-Handle. Is the R&D the flexible type that loops back towards you and is easier to adjust? The T-Handle still looks like a pain in the butt with the carb back in. I want to nut it the first time if possible.

Share this post


Link to post
Share on other sites

I understand that EVERYONE has there opinion & that's cool; but, when I see some thoughts thrown out there that contradict my own Baja-Experience & 5,000+ miles a year on the Penninsula...?

Well, the simple fact is FMF Pipes ain't Fragile and their silencers are among the VERY FEW that can make it all the way down to the "TIp" (LaPaz/Cabo) INTACT.

Been there, done that, got the pipes...only -2- over 3 years and that was simply to make the bike prettier: I like a Fresh Looking pipe! 17,000 miles: 3 Rips, 2 Beach Bashes, 2 Baja 500 + 2 Baja 1000 Pre-runs, 1 B-Day at the Beach Ride, 1 Hell Ride, 1 Catalina GP, 1 200 mile day "Sound-Testnig" for California State Parks, 1 250 mile Test Day in the Hi-Dez...etc.

That's some of what's in the Log-Book for the "17X"...btw...the Bike we're talking about is Affectionately referred to as my "Pre-Runner". This very same bike ran a Ti 5 PC "JCR" Pipe at the Glen Helen 24 HR and it worked damn nice, too!

On the other-hand: One of the Brands that's been suggested BROKE-OFF at the HEADER-FLANGE right n the middle of the Santa Rita Whoops. DOH! Btw, it wasn't DrD or PC.

So to Re-Cap: I've run an FMF for THOUSANDSof Miles & it's a Power-Maker, it's quiet, it LASTS.

I'm jus' sayin'...

Share this post


Link to post
Share on other sites

I understand that EVERYONE has there opinion & that's cool; but, when I see some thoughts thrown out there that contradict my own Baja-Experience & 5,000+ miles a year on the Penninsula...?

Well, the simple fact is FMF Pipes ain't Fragile and their silencers are among the VERY FEW that can make it all the way down to the "TIp" (LaPaz/Cabo) INTACT.

Been there, done that, got the pipes...only -2- over 3 years and that was simply to make the bike prettier: I like a Fresh Looking pipe! 17,000 miles: 3 Rips, 2 Beach Bashes, 2 Baja 500 + 2 Baja 1000 Pre-runs, 1 B-Day at the Beach Ride, 1 Hell Ride, 1 Catalina GP, 1 200 mile day "Sound-Testnig" for California State Parks, 1 250 mile Test Day in the Hi-Dez...etc.

That's some of what's in the Log-Book for the "17X"...btw...the Bike we're talking about is Affectionately referred to as my "Pre-Runner". This very same bike ran a Ti 5 PC "JCR" Pipe at the Glen Helen 24 HR and it worked damn nice, too!

On the other-hand: One of the Brands that's been suggested BROKE-OFF at the HEADER-FLANGE right n the middle of the Santa Rita Whoops. DOH! Btw, it wasn't DrD or PC.

So to Re-Cap: I've run an FMF for THOUSANDSof Miles & it's a Power-Maker, it's quiet, it LASTS.

I'm jus' sayin'...

Very good.

I've had the exact opposite experience in 1/10 the miles. Specifically, the can deforms, and then if you try and take it apart to re-pack it, you can't get it back together cleanly, and then the rivets oval out. The FMF can's I've use are also thinner, so if you fall on them, or back into a hill, the can is destroyed. I see this on the trail too, guys with FMF cans that are just falling apart, and are un-repairable.

I've never had any issues with the mid pipes or headers. I ride about 3,500 miles a year, but no 'tip-ripping'.

I currently run DR D on one bike, and Stock KTM on the other.

My last KTM had the PC T-5 and it was amazingly strong and quiet.

The KTM stock can is beefy and heavy, and restrictive..

The Dr D can is beefy too, but light, but the internal spot welds that held the perf core in place broke, and the core no longer lines up. But then, it has over 400 hours on it......

I've had Big Gun (total junk), Two Brothers (extremely nice and great power spread), Dr D, PC, MRD, Barnum, White Bros, FMF Q, Q-4, Powercore, Powercore II, Shorty, 4.0, 4.1, and probably others I forgot about. Of all of them, the FMF product was the most fragile, for me.

Your mileage may vary.

Edited by Krannie

Share this post


Link to post
Share on other sites

I understand that EVERYONE has there opinion & that's cool; but, when I see some thoughts thrown out there that contradict my own Baja-Experience & 5,000+ miles a year on the Penninsula...?

Well, the simple fact is FMF Pipes ain't Fragile and their silencers are among the VERY FEW that can make it all the way down to the "TIp" (LaPaz/Cabo) INTACT.

Been there, done that, got the pipes...only -2- over 3 years and that was simply to make the bike prettier: I like a Fresh Looking pipe! 17,000 miles: 3 Rips, 2 Beach Bashes, 2 Baja 500 + 2 Baja 1000 Pre-runs, 1 B-Day at the Beach Ride, 1 Hell Ride, 1 Catalina GP, 1 200 mile day "Sound-Testnig" for California State Parks, 1 250 mile Test Day in the Hi-Dez...etc.

That's some of what's in the Log-Book for the "17X"...btw...the Bike we're talking about is Affectionately referred to as my "Pre-Runner". This very same bike ran a Ti 5 PC "JCR" Pipe at the Glen Helen 24 HR and it worked damn nice, too!

On the other-hand: One of the Brands that's been suggested BROKE-OFF at the HEADER-FLANGE right n the middle of the Santa Rita Whoops. DOH! Btw, it wasn't DrD or PC.

So to Re-Cap: I've run an FMF for THOUSANDSof Miles & it's a Power-Maker, it's quiet, it LASTS.

I'm jus' sayin'...

I guess you just have better luck with FMF than others. I live in Baja and ride at least 3 days a week thousands of miles a year on 3 different 450X's. I've gone through three different FMF Q4's that broke off during crashes and weren't repairable. Now I run the PC JCR full exhaust and I love it! I crashed hard last month prerunning the 1000 and bent the crap out of the slip on. When I got back I bent it back and straightened it all out like new. Very tough pipe! The FMF does make great power and probably lasts if you never crash, but if you don't ever crash, your not going fast enough.

Share this post


Link to post
Share on other sites

I've had both PC and FMF on different bikes. Both have been durable during regular use and crashes. I've had aluminum cans (PC on CRF230F), carbon fiber cans (FMF on WR250F), and titanium cans (FMF on 450X). I've run both SS (on PC) and Ti (on FMFs) headers.

Here's some curves done a few years ago by a dirt bike mag for a 450X. Note that stock pipe has a flat spot at 6-7K and a peak at 8k, so it feels like it has a "hit" at high rpm.

FMF pipe pulls smooth from low rpm (3500) to peak. Couple extra hp at peak. Much more linear and smooth than stock.

Also below is Pro Circuit curve. Again, more linear and a couple extra hp at peak. Not sure if it's a test artifact, but shows power rolls on ~500 rpm later than FMF pipe. Otherwise, FMF and PC curves are very similar.

450Pipespage3.jpg

450Pipespage4.jpg

FMF Ti muffler can tucks up well behind 450X plastic.

PowerCoreInsert.jpg

Ti Powerbomb header covered by Eline carbon fiber heat shield. Suprisingly robust. It's durability has suprised me.

DSCN0480.jpg

Share this post


Link to post
Share on other sites

Well, PC makes FIVE different pipes for the X, so you are right, but wrong.

Dr D makes THREE different pipes for the X, with THREE different noise inserts. So again.....

I was referring to the Ti5 PC pipe which is loud but in my opinion runs among the best of any pipe. I will agree that it seems to be built the most "beefy" of the bunch.

Not sure of the name, but the full race Dr D with no insert is the loudest pipe I have ever heard. Doesn't really bother me, but could bother some.

Currently I am running a Ti Powercore and love the spread. My pipe has thousands of miles on it with no issues so far. Maybe a 1000 or so with Teamgreen himself. I will admit to seeing one fail however while "ripping".

My FMF gripe has to do with the fact that they will not sell parts. If you do crash and bust a muffler hanger they force you to buy a whole new muffler, or go to ebay and buy a broken one for parts...

Edited by dbedy

Share this post


Link to post
Share on other sites

I understand that EVERYONE has there opinion & that's cool; but, when I see some thoughts thrown out there that contradict my own Baja-Experience & 5,000+ miles a year on the Penninsula...?

Well, the simple fact is FMF Pipes ain't Fragile and their silencers are among the VERY FEW that can make it all the way down to the "TIp" (LaPaz/Cabo) INTACT.

Been there, done that, got the pipes...only -2- over 3 years and that was simply to make the bike prettier: I like a Fresh Looking pipe! 17,000 miles: 3 Rips, 2 Beach Bashes, 2 Baja 500 + 2 Baja 1000 Pre-runs, 1 B-Day at the Beach Ride, 1 Hell Ride, 1 Catalina GP, 1 200 mile day "Sound-Testnig" for California State Parks, 1 250 mile Test Day in the Hi-Dez...etc.

That's some of what's in the Log-Book for the "17X"...btw...the Bike we're talking about is Affectionately referred to as my "Pre-Runner". This very same bike ran a Ti 5 PC "JCR" Pipe at the Glen Helen 24 HR and it worked damn nice, too!

On the other-hand: One of the Brands that's been suggested BROKE-OFF at the HEADER-FLANGE right n the middle of the Santa Rita Whoops. DOH! Btw, it wasn't DrD or PC.

So to Re-Cap: I've run an FMF for THOUSANDSof Miles & it's a Power-Maker, it's quiet, it LASTS.

I'm jus' sayin'...

Hey Manny, how bout those carbon cans?? :)

  • Like 1

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:

Sign in to follow this  

×