i need a lesson in jetting
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From: Western PA
Ok guys, so here are my dyno charts. I am pleased to see I picked up the horsepower I was looking for, however, the guy at the shop says I'm too rich. Unless I'm interpreting the charts wrong, I think I am lean. They did a 3rd gear roll on, a 10% throttle test, and ran through all 6 gears. Let me know what you guys think. Maybe it's time to switch to those 48 pilots as residentg suggested. The shop says turn the pilots out more and bring the needles down to 4th groove. I'm knida stumped. The bike pulls strong from idle to redline. I just want to ensure i'm tuned optimally. For those of you who havent read/forgot my settings here they are:
180 front
185 rear
45 pilots
needles 5th groove
pilot screw 2.5 turns out
Any advice is much appreciated. Thanks guys!!
180 front
185 rear
45 pilots
needles 5th groove
pilot screw 2.5 turns out
Any advice is much appreciated. Thanks guys!!
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Posts: 2,091
From: Lithia, FL
Ok guys, so here are my dyno charts. I am pleased to see I picked up the horsepower I was looking for, however, the guy at the shop says I'm too rich. Unless I'm interpreting the charts wrong, I think I am lean. They did a 3rd gear roll on, a 10% throttle test, and ran through all 6 gears. Let me know what you guys think. Maybe it's time to switch to those 48 pilots as residentg suggested. The shop says turn the pilots out more and bring the needles down to 4th groove. I'm knida stumped. The bike pulls strong from idle to redline. I just want to ensure i'm tuned optimally. For those of you who havent read/forgot my settings here they are:
180 front
185 rear
45 pilots
needles 5th groove
pilot screw 2.5 turns out
Any advice is much appreciated. Thanks guys!!
180 front
185 rear
45 pilots
needles 5th groove
pilot screw 2.5 turns out
Any advice is much appreciated. Thanks guys!!
Out of my mind, back in 5
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Joined: Nov 2006
Posts: 6,109
From: Skurup, Sweden
Ok guys, so here are my dyno charts. I am pleased to see I picked up the horsepower I was looking for, however, the guy at the shop says I'm too rich. Unless I'm interpreting the charts wrong, I think I am lean. They did a 3rd gear roll on, a 10% throttle test, and ran through all 6 gears. Let me know what you guys think. Maybe it's time to switch to those 48 pilots as residentg suggested. The shop says turn the pilots out more and bring the needles down to 4th groove. I'm knida stumped. The bike pulls strong from idle to redline. I just want to ensure i'm tuned optimally. For those of you who havent read/forgot my settings here they are:
180 front
185 rear
45 pilots
needles 5th groove
pilot screw 2.5 turns out
Any advice is much appreciated. Thanks guys!!
180 front
185 rear
45 pilots
needles 5th groove
pilot screw 2.5 turns out
Any advice is much appreciated. Thanks guys!!
To simplify a little, that red line there is at 13... I'd like that too be "midline" in your AF graph... Then you'd be making about the same power as now, and not wasting a lot of fuel... Because that midrange dip is definetly rich...
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From: Fulton, MO
The red dotted line is whatever you want it to be, i.e. whatever the tech is shooting for. I4's tend to run most power with a slightly leaner mixture, probably because the cylinders are smaller and you get better combustion. The twins like to be around a 12.5 ratio. So, in looking at your graphs, I'd say that the tech is spot on. You need to lower the needle a notch, your mains are perfect, and as long as it idles smoothly then your mixture and idle settings are good. BTW, you say 5th notch, but 5th notch from what? Top or bottom? Needle position highest or lowest?
[Edit] Looking at it again, you might be able to get a little more power by going one bigger on the mains, but it's based on your elevation too. You could play around with it to get the best top end power if you wanted to.
[Edit] Looking at it again, you might be able to get a little more power by going one bigger on the mains, but it's based on your elevation too. You could play around with it to get the best top end power if you wanted to.
Out of my mind, back in 5
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From: Skurup, Sweden
Like Hawkrider said, that line is setup as a "target" by the operator... On your graph it's set at 13... And in the middle there you are down to 11'ish... Like said, you will get a few dips below the line and a few small hills above... But if you try to even things out around that line, somewhere between 12-13 is where the hawk makes loads of power, a bit different from bike to bike where you end up... If you have the AF there where you need it in the revband, and around there through it all, it makes all the difference... But perfect is impossible...
BTW, thinking this through a second time I realize I could just have said "I agree with Hawkrider"... I'm not adding much of anything new...
Just one tidbit... Don't go staring at the numbers I post, or Hawkrider or anyone else post... 12.5 AF works good... So does 12.7... Or 13... None of it is set in stone... You will find a setup that gives your bike a "smooth" line on AF as well as torque/hp... And when you find that sweet spot which gives you small, smooth swings all over the revband it will give you the best possible result for your bike... But when the AF is going up or down in a specific area like that, it means you can improve on the setup...
BTW, thinking this through a second time I realize I could just have said "I agree with Hawkrider"...
I'm not adding much of anything new... Just one tidbit... Don't go staring at the numbers I post, or Hawkrider or anyone else post... 12.5 AF works good... So does 12.7... Or 13... None of it is set in stone... You will find a setup that gives your bike a "smooth" line on AF as well as torque/hp... And when you find that sweet spot which gives you small, smooth swings all over the revband it will give you the best possible result for your bike... But when the AF is going up or down in a specific area like that, it means you can improve on the setup...
Last edited by Tweety; Jun 2, 2010 at 04:34 PM.
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From: Western PA
Thanks for the input guys! Hawkrider, to answer your question, I'm set at 5th groove from top. Sorry I forgot to specify. Thanks again! I was thinking maybe a half step adjustment may be a good starting point. That is what those adjusting washers are for right? If I'm wrong please correct me.
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From: Western PA
Ok guys. Looking for some suggestions. As can be seen above my dyno graphs show that I was rich. Setting at time of dyno run were 180 front, 185 rear mains, 45 pilot jets, pilot screws 2.5 turns out, needles 5th groove from top. Today, I lowered the needles to 4.5 from the top. I put the clip on 4th groove from the top then put the small dynojet washer on the tapered end of the needle. This is how you accomplish half step adjustments, right? Anyway...it seemed to run great. Except one time when I first test rode it, I could feel a clunk under the tank between 3/4k rpms. Just like before when I was having carb backfires due to a lean condition. It didn't happen again while on a 120 mile ride. I repeatedly tried to make it happen again by holding the throttle in the spot where it occured. It didn't. The other thing I noticed was that the exhaust was occassionally popping on decel--whereas it mostly gurgled before. It is my understanding that if PAIR is removed and you have popping on decel, you are lean. Is this true? Time for 48 pilots, as residentg suggested? Or bigger mains? Could such a small adjustment cause me to go from very rich to lean? Any ideas or suggestions? Thanks all
Last edited by steve29; Jun 7, 2010 at 05:41 PM.
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Did you do a carb sync after all this jetting? Remember, those big carbs, even when jetted properly, still do strange things like backfire sometimes. I get one every once in a while too.
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Hey Steve, anytime that you make a change to your needle height there will be an effect on idle mixture as well. Since you took away a little fuel with the needles, I would think that putting some back with the mixture screws should cure the idle problem that you have described.
Try turning the mixture screws OUT 1/8 turn and see if it does not clear up the issue.
Try turning the mixture screws OUT 1/8 turn and see if it does not clear up the issue.
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From: Western PA
Tim, I will give that a shot. Thanks guys!
Last edited by steve29; Jun 8, 2010 at 05:15 PM.
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From: Western PA
Hello all. I'm starting to think I need to go up on my mains to 190/195. (current settings and dyno charts above and on previous page) According to the factory pro website and from what other forum members have stated, having incorrect mains often results in "severe tweaking" of the midrange. Which I definitely have encountered. No matter what I do with the needles and pilot screws, I'm either too rich, or too lean. Even tried half step incriments. I guess if I step up the mains, I will be safely rich and able to drop the needles a bit. I am considering a change to 48 pilots, but I'm conflicted on that. Guys have said that Dynojet doesn't recomend it. Kind of lost here. Thoughts? Thanks
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It's a good idea to sync the carbs every time you've pulled them up, regardless of what you did or didn't do while they were up.
Like Hawkrider intimated, I wouldn't draw any big, sweeping conclusions from the fact that you're bike hiccuped once, especially since you tried and failed to get it to repeat. Actually, unless it started happening repeatedly, I'd forget about it.
Dynojet recommends needles 5 from the top with free flow exhaust and filter, so if it runs well that way it's fine.
If the dyno tech and experienced tuners/graph readers on the forum think you're running slightly rich now, I don't understand why you'd consider going up two sizes on the main jets.
Like Hawkrider intimated, I wouldn't draw any big, sweeping conclusions from the fact that you're bike hiccuped once, especially since you tried and failed to get it to repeat. Actually, unless it started happening repeatedly, I'd forget about it.
Dynojet recommends needles 5 from the top with free flow exhaust and filter, so if it runs well that way it's fine.
If the dyno tech and experienced tuners/graph readers on the forum think you're running slightly rich now, I don't understand why you'd consider going up two sizes on the main jets.
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From: Western PA
After dropping the needles to 4.5 from top by using the dynojet washers (if i did that correctly) the bike feels more responsive, but like I said before I'm getting the occasional lean stumble. Got a few today. Only in first gear though. I'm just lost.
What if I went 175/180 and raised the needles back to 5th groove from top? The bike never stumbled on that needle position, but it was rich. Dropping down a half step caused some stumbles. Would the smaller main size lean the mixture enough that going back to 5th groove from top would no longer be too rich? I just can't believe a half step on the needles changed that much. It kind of seems like no matter what else i do, I need to be on the 5th from top to avoid lean stumbles. If that position was too rich with 180/185 mains, it seems like the only thing left to do is go to 175/180. I don't profess to be an expert on this, so if that sounds idiotic, please correct me.
Last edited by steve29; Jun 8, 2010 at 08:30 PM.
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Unless I interpret it incorrectly, from what I gathered from the factory pro website and from some of the forum members, you want to use bigger mains so you can avoid raising the needles to fix lean holes. I'm probably wrong on that.
After dropping the needles to 4.5 from top by using the dynojet washers (if i did that correctly) the bike feels more responsive, but like I said before I'm getting the occasional lean stumble. Got a few today. Only in first gear though. I'm just lost.
What if I went 175/180 and raised the needles back to 5th groove from top? The bike never stumbled on that needle position, but it was rich. Dropping down a half step caused some stumbles. Would the smaller main size lean the mixture enough that going back to 5th groove from top would no longer be too rich? I just can't believe a half step on the needles changed that much. It kind of seems like no matter what else i do, I need to be on the 5th from top to avoid lean stumbles. If that position was too rich with 180/185 mains, it seems like the only thing left to do is go to 170/175. I don't profess to be an expert on this, so if that sounds idiotic, please correct me.
After dropping the needles to 4.5 from top by using the dynojet washers (if i did that correctly) the bike feels more responsive, but like I said before I'm getting the occasional lean stumble. Got a few today. Only in first gear though. I'm just lost.
What if I went 175/180 and raised the needles back to 5th groove from top? The bike never stumbled on that needle position, but it was rich. Dropping down a half step caused some stumbles. Would the smaller main size lean the mixture enough that going back to 5th groove from top would no longer be too rich? I just can't believe a half step on the needles changed that much. It kind of seems like no matter what else i do, I need to be on the 5th from top to avoid lean stumbles. If that position was too rich with 180/185 mains, it seems like the only thing left to do is go to 170/175. I don't profess to be an expert on this, so if that sounds idiotic, please correct me.
First, are you using the OEM air filter?
Second, I don't know as much about all this as some other folks here, I just know what worked really well for me.
With slip ons and the OEM air filter I've got 175f/180r and needles 5th from top with Dynojet kit. Never been on a dyno or had the exhaust gas analysed, but it runs perfectly everywhere. When I shut down, pull over, pull and examine the plugs, they look like the "ideal" photos in the spark plug brochures.
I don't know. If my bike was running as well and getting as good mileage as you reported with 180/185 and needles 5 from the top, I'd probably leave it alone and just go ride the thing.
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Yep OEM filter. How many turns out are your screws? If you are running great on 5th from top with 175/180, I may have to try that. It's about the only thing left to do other than changing pilots. I seem to be right on that line where one small change either way throws everything out of whack. I don't know that putting the needles back to 5th clip from top and leaving it at that is an option for me personally. Mostly because I know its not correct as shown by the dyno (although it ran without lean holes). I'm willing to bet with 175/180s like you have, I can lose the lean holes and not be overly rich like I was on 5th from top, 180/185.
Last edited by steve29; Jun 8, 2010 at 08:59 PM.
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Yep OEM filter. How many tunrs out are your screws? If you are running great on 5th from top with 175/180, I may have to try that. It's about the only thing left to do other than changing pilots. I seem to be right on that line where one small change either way throws everything out of whack.
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I recently got Yoshimura slip-ons, and even with the street baffles removed, it's running a little rich at idle but great everywhere else. I had shimmed the needles .020" about a year ago, and installed 48 pilot jets after getting the slip-ons (courtesy of the distracted 19 year old who rear ended me at a red light). I had a tech adjust the idle mixture, but its still rich, stalls at idle at 2000 feet or higher. I've got the Honda pilot screw tool on order from the dealer so I can solve that problem.
Bottom line, even with just the .020" needle shim and before installing the 48 pilots, I noticed stronger top end and it revved freely. I've got stock mains and an OEM filter.
Bottom line, even with just the .020" needle shim and before installing the 48 pilots, I noticed stronger top end and it revved freely. I've got stock mains and an OEM filter.
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Have you cleaned your carbs? I'm guessing yes, but if not, removing the jets and soaking them in carb spray may help.
My '05, with 38k miles at the time, had a completely plugged pilot jet on #2 carb, and #1 was barely open when I cleaned them just a week before I was hit.
My '05, with 38k miles at the time, had a completely plugged pilot jet on #2 carb, and #1 was barely open when I cleaned them just a week before I was hit.
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I recently got Yoshimura slip-ons, and even with the street baffles removed, it's running a little rich at idle but great everywhere else. I had shimmed the needles .020" about a year ago, and installed 48 pilot jets after getting the slip-ons (courtesy of the distracted 19 year old who rear ended me at a red light). I had a tech adjust the idle mixture, but its still rich, stalls at idle at 2000 feet or higher. I've got the Honda pilot screw tool on order from the dealer so I can solve that problem.
Bottom line, even with just the .020" needle shim and before installing the 48 pilots, I noticed stronger top end and it revved freely. I've got stock mains and an OEM filter.
Bottom line, even with just the .020" needle shim and before installing the 48 pilots, I noticed stronger top end and it revved freely. I've got stock mains and an OEM filter.
On the D-ring thing, what many of us have done once we removed the pilot screw is dremel a screwdriver slot in the head, perpendicular to the D, so that we never have to use the D-tool again.
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Thanks all. I guess I just have to accept the fact that I am gonna need to use those 48 pilots. There's really nothing else I can do. The only other options I came up with where going up to 185/190 and leaning out the midrange by dropping the needle to 4th from top. Or going 175/180 and fattening up the mid by going 5th from top. Which one to persue is a mystery to me, if I should even try one or both of them. In my head these theories make sense, but maybe that's why I'm still dicking around with this thing. Haha. I'm willing to bet that using 48s would cure the problem. I'm just kinda stuck on dynojet's claim that if you go that route, you obviously didn't get something right. I'm learning quickly that the hawk is difficult to tune. Anybody else using a DJ kit go to 48 pilots? If so, what was your experience with it?
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I recently got Yoshimura slip-ons, and even with the street baffles removed, it's running a little rich at idle but great everywhere else. I had shimmed the needles .020" about a year ago, and installed 48 pilot jets after getting the slip-ons (courtesy of the distracted 19 year old who rear ended me at a red light). I had a tech adjust the idle mixture, but its still rich, stalls at idle at 2000 feet or higher. I've got the Honda pilot screw tool on order from the dealer so I can solve that problem.
Bottom line, even with just the .020" needle shim and before installing the 48 pilots, I noticed stronger top end and it revved freely. I've got stock mains and an OEM filter.
Bottom line, even with just the .020" needle shim and before installing the 48 pilots, I noticed stronger top end and it revved freely. I've got stock mains and an OEM filter.
