Hehehehe.....you guys wanted a new post, here goes. :cool:
When I put my new exhaust on this evening, I am going to take my carbs back off. I am going to install 107.5 main jets, put another shim on my needles for a total of 3, and not sync the carbs. Then I will turn my pilots out 3-1/4 turns from a light seat. From what I have gathered, I believe this will be real close on carburation. Opinions? Comments? :cool:
NOT SYNC THE CARBS, YIKES!! (http://i203.photobucket.com/albums/aa214/TLRam1/Smilies/Smiley-bugeye.gif) :P :P
Let us know how you come out.
http://www.youtube.com/watch?v=uh-UOplGXzU (http://www.youtube.com/watch?v=uh-UOplGXzU)
You real gear-heads probably won't get much out of this, but I did. I just wish I could find a video for the V45.
Too bad I'm blocked from you tube at work... :-x :-x
I just ordered the 115 jets for my setup. i plan on trying the 115 jets, 2 shims and 45 pilots turned down to about 2.5 turns for a starting point. probably wont get to ride much this year because of finances but wanted to at least run it a few times on the balding tires and get feel for more jetting uptop. i think the 45 pilots could be 42's but no smaller for sure. since i laready have the 45's i'll just go with them and turn them in a bit and check it then.
Quote from: chadschloss78 on February 11, 2009, 01:34:18 PM
I just ordered the 115 jets for my setup. i plan on trying the 115 jets, 2 shims and 45 pilots turned down to about 2.5 turns for a starting point. probably wont get to ride much this year because of finances but wanted to at least run it a few times on the balding tires and get feel for more jetting uptop. i think the 45 pilots could be 42's but no smaller for sure. since i laready have the 45's i'll just go with them and turn them in a bit and check it then.
115 main jets! :shock: :shock: Your making my upgrade look small. Wonder how much harder will it pull with those jets? Do you think you will be rich on mid and top end?
right now, for me, it's not rich at all except in the low end. i can baby this thing and get about 48-50 mpg. i can romp on it and get 30mpg. (even using a 15 tooth front sprocket/40 rear) i know the low end is rich, i have the pilots size 45 and 3 turns out. but that makes up for the top end. even at WOT you are still pulling from the slow speed jet. i can turn the slow speed jet up to 3.5 and the top end loves it, but after the bikes all warmed up, it's boggy down low off of take off. i can leave it at 3 turns out and it's a good spot, but i want more top end now that i know it will take it. the jetting is all relative to each other. the low is always in play, even at mid throttle and high end. the top end jetting has to be done first, then the midrange, then the float settings (if adjustable) but our magna's are not, then the slow jets. check out this article below. i think it's spot on after trying to do this myself, just by the feel of the bike and seat of the pants feel. i started at the bottom and worked my way up, but that seems to be wrong. if i up it to 115 mains, i think i MAY be too rich in the midrange, hence the 2 shims instead of the 3 i have now. i can cruise right now at speeds/gears most can't, like 2-3k in traffic in 3rd or 4th gear and not bog down. gently cruizing at 55 in 5th with the throttle barely open. i can't be too far off from ideal with my setup. when i've tried 2.5/2.375 turns out on the screws, it pops too much on decel and top end is not there as much, and with the throttle wide open in 4th gear, it lags a bit, but if i let up it picks up speed meaning the main jet is still too small. at 3 turns out, the top end is better, can go wide open with the throttle and not pick up speed, but the low end is too rich, sooty exaust pipes and not as crisp down low when rapping on the throttle. so i am going to try 115 mains, 2 shims and 2.5 turns on the screws. i also have the dyna 3000 ignition module, dyna coils, dyna wires, and pingel petcock which flows better than the stock petcock, bypassed fuel shutoff, k&n filter, vance& hines pipes. so i think i'm a little bit different from most. i wanted to build a 'sleeper' and i think i'm very close. if this works, i'll go up to a 17 tooth sprocket to save even more $$ on gas. i'd also like to try to advance the base timiing by moving the pickup coil a little bit and advance the timing by about 4 degrees. i think this is possible by slotting the bracket that the pickup mounts to. i've seen this done on other honda bikes and it works out good and saves money on gas, and speeds up the bike a bit.
READ THIS (COPIED FORM FACTORY PRO.com)
Follow steps in order....First, dial in:
1. Top end (full throttle / 7.5k to redline -
Best Main Jet must be selected before starting step 2 (needle height)!
Select Best Main Jet
To get the best, most even top end power (full throttle/after 7500 rpm), select the main jet that produces the hardest pull at high rpm.
If the bike pulls harder at high rpm when cold and less hard when fully warmed up, the main jet is too large. Install a smaller main jet and retest until you find the main jet that pulls the hardest at high rpm when fully warmed up. This must be done first - before moving on to the other tuning ranges.
If the bike doesn't pull well at high rpm when cold and gets only slightly better when fully warmed up, the main jet is too small.
In order to properly tune the midrange and low rpm carburetion, THE MAIN JET MUST FIRST BE PROPERLY SELECTED after 10 to 15 minutes of hard use!
Do not pay too much attention to the low-end richness when you are changing main jets - you still need to be using the main jets that produce the best power at high rpm. You will deal with the low-end / cruise later - after step 2.
2. Midrange (full throttle /5k-7k)
Step 1 (Best Main Jet) must be selected before starting step 2!
Select best needle clip position
To get the best power at full throttle / 5k-7k rpm, adjust the needle height, after you have already selected the best main jet.
If the engine pulls better or is smoother at full throttle/5k-7k in a full throttle roll-on starting at <3k when cool but soft and/or rough when at full operating temperature, it is too rich in the midrange and the needle should be lowered.
If the engine pulls better when fully warmed up but still not great between 5k-7k, try raising the needle to richen 5k-7k.
If the engine pulls equally well between 5k-7k when cooler as compared to fully warmed up, the needle height is probably properly set.
Do not pay too much attention to the low-end richness when you are changing needle clip positions - you still need to be using the clip position that produces the best full throttle / 5k-7k power in conjunction with the main jets (Step 1) that produce the best power at high rpm. You will deal with the low-end / cruise next.
3. Low end (full throttle / 2k-3k)
Step 1 (Best Main Jet) and Step 2 (needle height) must be selected before starting step 3!
Float height (AKA fuel level & how to..)
To get best low-end power, set float height (fuel level) so that the engine will accept full throttle, without missing or stumbling, in 2nd gear from 2.5k to 3k rpm at minimum.
Float heights, unless otherwise specified in the installation guide, are measured from the "gasket surface" of the carb body to the highest part of the top of the float - with the float tang touching but not compressing the float valve spring.
If the engine has a "wet" rhythmic, soggy area at full throttle / 3k-4k rpm, that gets worse as the engine heats up, lower the fuel level by resetting the float height 1mm greater (if the original was 13mm - go to 14mm). This will lower the fuel level, making full throttle / 2k-3k rpm leaner.
If the engine is "dry" and flat between 2k to 3k rpm, raise the fuel level.
Example: change float height from 15mm to 14mm to richen up that area.
REMEMBER, since the main jet WILL affect low speed operation, the MAIN JET has to be within 1 or 2 sizes of correct before final float setting.
Warning: If the engine is left with the fuel level too high,, the engine may foul plugs on the street and will be "soft" and boggy at part throttle operation. Adjust Floats to raise/ lower the Fuel Level.
Base settings are usually given if a particular application has a history of fuel level criticalness. The Fuel level height in the float bowl affects full throttle/low rpm and, also, richness or leanness at cruise/low rpm.
Reference: a bike that runs cleanly at small throttle openings when cold, but starts to show signs of richness as it heats up to full operating temperature, will usually be leaned out enough to be correct if the fuel level is LOWERED 1mm. Check out and RESET all: Suzuki (all), Yamaha (all) and Kawasaki (if low speed problems occur). Needless to say, FUEL LEVEL IS EXTREMELY IMPORTANT!!!
If there are low-end richness problems, even after lowering the fuel level much more than 1.5mm from our initial settings, check for needle wear and needle jet (part of the emulsion tube). See Worn Needle and Worn Needle Jet diagram. It is VERY common for the brass needle jets (in the top of the "emulsion tube") in 36mm, 38mm and 40mm Mikuni CV carbs to wear out in as little as 5,000 miles. Check them for "oblong" wear - the needle jet orifice starts out round! Factory Pro produces stock replacement needle jets / emulsion tubes for 36mm and 38mm Mikuni carbs. Click here
4. Idle and low rpm cruise
Fuel Screw setting (AKA mixture screws)
There is usually a machined brass or aluminum cap over the fuel screws on all but newer Honda. It's about the diameter of a pencil. Cap removal details. Newer Honda carbs have no caps, but use a special "D" shaped driver, usually supplied in the carb recal kit. We do have them available separately, too. 800 869-0497 to order -
Set for smoothest idle and 2nd gear, 4k rpm, steady state cruise operation. Set mixture screws at recommended settings, as a starting point. For smoothest idle, 2nd gear 4000 rpm steady state cruise , and 1/8 throttle high rpm operation. (pj tuning information)
Pilot fuel mixture screw settings, float level (but, you've "fixed" the fuel level in Step 3 - which you have already done!) AND pilot jet size are the primary sources of mixture delivery during 4000 rpm steady state cruise operation.
If lean surging is encountered, richen mixture screws (turn out) in 1/2 turn increments. Alternative pilot jets are supplied when normally required.
Pilot fuel mixture screw settings, float level and pilot jet size also affect high-rpm, 0 to 1/8 throttle maneuvers. Too lean, will cause surging problems when the engine is operated at high rpm at small throttle openings! Opening the mixture screws and/or increasing pilot jet size will usually cure the problem.
NOTE: A rich problem gets worse as the engine heats up.
If the throttle is lightly "blipped" at idle, and the rpm drops below the set idle speed, then rises up to the set idle speed, the low speed mixture screws are probably set too rich: try 1/2 turn in, to lean the idle mixture.
NOTE: A lean problem gets better as the engine heats up.
If the throttle is lightly "blipped" at idle, and the rpm "hangs up" before dropping to the set idle speed, and there are no intake leaks and the idle speed is set at less than 1000 rpm, the mixture screws are probably too lean: try 1/2 turn out, to richen mixture. Be sure there are no intake leaks and the idle speed is set at less than 1000 rpm!
Carb Kit Design is a combination of science, art, intuition and and at times, a fair dose of wizardry. There is no dyno that "tells" one how to assemble or modify the carb to deliver proper power and response.
Perfect Carb Kit TUNING requires patience and perseverance and "reasonable" feel to feel the changes - of which - most motorcycle riders have a good ability to do.
When a dyno "operator" says he/she has to ride the bike after dyno tuning to do the final tune for cruise smoothness - that's what they are doing. Avoid any dyno operator who says that they don't have to do that!!!
The only dyno that I know of that will duplicate and visually display the engine smoothness is the EC997 dyno (yes, I know, we make it) - that's one reason why, if you can, you'd like to use one for tuning - a smoother engine IS getting the best mixture. Other dynos claim to "tune to an "A/F Ratio" - probably the biggest marketing scheme in the dyno industry at this time - and they never can equal the quality of tune as designed -
These tuning kits have been thoroughly tested to ensure easy, trouble-free, optimized performance.
Please note: If you have installed the kit and gone through the optional screw settings, clip positions and main jets, and still have a persistent flat spot/problem, we ask you to call us. Unique engine / exhaust / filter / altitude / temperature combinations may require individualized setups. We are here to help. The information gained to your solution will be installed in our computerized reference database. PLEASE CALL!
We ask that upon completion of installation and tuning, that you call us with specifications of your installation, (pipe brand, filters, advancer, altitude, humidity, temperature and final carb settings) to be entered in our TUNING DATABASE. The database allows us to include the "most used" jet sizes and setup specifications in every kit.
Use (415) 491-5920, (800) 869-0497 or fax (415) 492-8803.
Thanks!
Marc W. Salvisberg
(copied form factorypro.com)
Pilot Jets
The affect of pj size change on idle and cruise operation
Question:
Greg Johnson wrote:
> I have installed one of your 1.0 jet kits on my R6 and I am coming to the final parts of tuning it.
> It runs well and passes most of the tests as provided on your tuning guide. It does, however, appear to be lean low down, as there is a "hole" when cracking the throttle wide open at below 2500rpm and at high rpm/part throttle, it shows some surging. I have though set the fuel screws, so that it idles correctly and returns to the correct rpm, when the idle is set below 1000rpm and the throttle is blipped.
> To fix the lean patch, is it better to go the next step up in pilot jets, rather than adjust the fuel screw?
> Will upsizing the pilot jet, require re-adjustment of the fuel screw and thus negating some of or all of the gains made by the larger pilot jet?
> Thanks,
> Greg J
Answer:
Greg - Good diagnosis on the pilot jet size -
As far as the pilot... Look at it this way...
There are 4 outlet holes for the pilot mixture. ~3-4 at the butterfly and one "downstream" of that (for 75% of the idle mixture).
1 hole is controlled by the mixture screw and with the other 3 or 4, max flow is limited by the size of the pilot jet.
At idle, 1 hole (metered by the fuel screw) and 1 un metered hole are open.
At cruise, when the "butterfly" is just "cracked", all 3-4 unmetered holes + the 1 metered one are uncovered -
So.....
At cruise, you get those 3 unmetered holes + the metered hole... So, at least 75% of the fuel delivered at cruise is limited by the size of the pilot jet.
At idle, you get 100% of the trimmed 1 hole + a butterfly valve-trimmed amount of the other 3-4 metered holes.
Rule of thumb....
If you go 1 size larger or smaller on the size of the pilot jet, you will change the fuel screw ~1.5x richer or leaner to retain the original idle mixture -
Example:
You have a #40 pilot jet installed (with the proper main, needle height and fuel level already done) and to get best idle, you are 4.0 turns out (from lightly bottomed out).
(Using another "rule of thumb", if you have the correct pilot jet, the fuel screw will end up at between 1.5x and 3.0x when set for best idle.)
Cruise seems lean....
So, I'd expect that I could richen the cruise with 1 size larger (42) pilot jet (size of pj is 75% of cruise mixture) and the "trim" the fuel screw "in" for best mixture for best idle (size of pilot is 25% of idle mixture).
To go back to ~ the same idle mixture, after going from 40 pj/4.0x to the 42........ try 2.5x
40 pj / 4.0x = our reference idle mixture
42 pj / 2.5x = ~ same idle mixture
38 pj /5.5x = ~ same idle mixture (this is a "stretch - after 4.5x, not much changes)
Marc
http://www.sa750.com/timingmod/timingmod.htm (advanceing the timing)
I put on the Vance and Hines exhaust thursday night. I had to modify the right rear exhaust header. Cut slots longer and grind on it some. Finally got it to fit properly. Other than that, beautiful exhaust. Started the bike, :shock: :shock: :shock: I had no idea how good this exhaust was going to sound. Like everyone says, you have to hear them to understand. One word, phenomenal. This is the best money I have spent on my bike hands down. I highly recommend this exhaust for any 3rd gen bike.
After riding on Friday,(vacation day) I noticed this exhaust flows extremely well. I need more midrange carburation. Carbs coming off this week. Once again, very pleased with the sound and detail of this exhaust!! :grin:
I would also so say you will need to go with a bigger Idle jet probably a 42 and one shim if you have a K&N then you might try the 108 mains!!!!
Ok, last night installed 108 main jets. Put another shim on the needles for a total of 3 shims per needle. Backed out the pilot's to 3-1/4 turns. I did not change the pilot jets to 42. Rode to work this morning, did not notice much difference. It did start a little easier this morning. I will give it time to adjust to the changes. I only live 6 miles from work. I will try to put some mileage on the setup this weekend sometime. I just can't get over the sound of this exhaust, very happy. :grin: