Carb Tuning at altitude

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Marc85

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I found an archived article related to carb tuning for people in Denver, however it appears to be for stock exhaust setups. I have a single K&N filter and UFO 4-2-1, I upped my main jets to 155 after putting the exhaust on. Does anyone have modification suggestions based on this document for my setup?


Hope you don't mind me jumping in here, but we recently redid the carbs on my V-max (I assume the Venture is very similar) and got some clarification from one of my friends that is a technical expert on the Max...keep in mind this is for an adjustment to Colorado altitude:

What we're going to do is replace the main jets in your float bowls with a 145 Mikuni jet. The stock jetting is a 152.5 which is a bit rich at sea level for a stock bike and WAY rich for a bike at 5000+ feet altitude. This will make the bike run more crisp along with giving it a better top end and better fuel mileage. Shane, you know what I mean by top end after seeing how easily I take my bike to 140+. It never pulled like that when I had the stock jetting in it. There is actually a calculation for determining jetting at altitude. Anyway, that's the story behind the main jet selection. The mains always have to be selected first. Without a good main jet selected, all the other 'circuits' of the carb will never be right. Now the 'pilot fuel jet' is the one that is size 42.5 Stock on a 49 state bike is 37.5 I don't know what a California bike has but I'll bet it's leaner if anything. With the 42.5 you won't have to have the idle mixture screws out so far and you'll also have a better crossover from idle to midrange. All in all, this means no more popping out the carb throats when you gas it from idle. The 'pilot air jet' is part of the same circuit that the we use the 'pilot fuel jet' in. Fuel jets let fuel in and air jets let air in to make a mixture that is fed down the carb throat at idle and slightly above. The 'pilot air jet' and the 'pilot fuel jet' both work together to give a proper mixture at idle and also up through midrange when using small throttle openings. In other words when you are cruising with the throttle held open just a bit. Like when you're going 30, 40, 50, or 60 MPH. It's this jetting arrangement that is too lean from the factory. This helps the factory get past missions testing. It's also the reason that the main is too big. They try and use a larger, too large in fact for best power, main jet to help compensate for a very lean idle mixture. As you can see from the popping that every stock jetted Vmax is plagued with, it's not a very good compromise. This is what we're attempting to fix. Now, this air jet I just mentioned is the same size (not the hole, but the physical size and the threads) as the main jet. That's why I told you guys to get 95 main jets. But Yamaha probably doesn't have a listing for a main of that size. Soooo, what you do is just order a 95 'pilot air jet,' because that is what it really is. You'll see when you get it that it's the EXACT same as your new main jets, just a number 95 and not a 145. The other 'pilot air jet' is called PAJ2,,, meaning 'pilot air jet number 2. It has an effect through the midrange before the jet needle takes over. This also is the same size as a main jet and that's also why I told you to get a 160 main jet. We just won't be using it in the main jet location. In this case, the stock jet (PAJ2) is a 170 and we are going to a 160. When fuel jets get larger, it means you're going richer. When air jets get larger, it means you're going leaner. Because fuel jets let in raw gas and air jets let in air. Basically, more fuel= richer,,, more air= leaner. What we really are dealing with is:

4 main jets in the size of '145' (3G2-14231-29-00)
4 pilot fuel jets in the size of '42.5' (4G0-14142-42-A0)
4 pilot air jets number 1 (PAJ1) in the size of '95' (3G2-14231-19-00)
4 pilot air jets number 2 (PAJ2) in the size of '160'" (3G2-14231-32-
00)

In addition you may also need the jet block gaskets (3JB-14199-00-00) depending on the age of your bike and the condition of your current gaskets.

Shane
 
I found an archived article related to carb tuning for people in Denver, however it appears to be for stock exhaust setups. I have a single K&N filter and UFO 4-2-1, I upped my main jets to 155 after putting the exhaust on. Does anyone have modification suggestions based on this document for my setup?


Hope you don't mind me jumping in here, but we recently redid the carbs on my V-max (I assume the Venture is very similar) and got some clarification from one of my friends that is a technical expert on the Max...keep in mind this is for an adjustment to Colorado altitude:

What we're going to do is replace the main jets in your float bowls with a 145 Mikuni jet. The stock jetting is a 152.5 which is a bit rich at sea level for a stock bike and WAY rich for a bike at 5000+ feet altitude. This will make the bike run more crisp along with giving it a better top end and better fuel mileage. Shane, you know what I mean by top end after seeing how easily I take my bike to 140+. It never pulled like that when I had the stock jetting in it. There is actually a calculation for determining jetting at altitude. Anyway, that's the story behind the main jet selection. The mains always have to be selected first. Without a good main jet selected, all the other 'circuits' of the carb will never be right. Now the 'pilot fuel jet' is the one that is size 42.5 Stock on a 49 state bike is 37.5 I don't know what a California bike has but I'll bet it's leaner if anything. With the 42.5 you won't have to have the idle mixture screws out so far and you'll also have a better crossover from idle to midrange. All in all, this means no more popping out the carb throats when you gas it from idle. The 'pilot air jet' is part of the same circuit that the we use the 'pilot fuel jet' in. Fuel jets let fuel in and air jets let air in to make a mixture that is fed down the carb throat at idle and slightly above. The 'pilot air jet' and the 'pilot fuel jet' both work together to give a proper mixture at idle and also up through midrange when using small throttle openings. In other words when you are cruising with the throttle held open just a bit. Like when you're going 30, 40, 50, or 60 MPH. It's this jetting arrangement that is too lean from the factory. This helps the factory get past missions testing. It's also the reason that the main is too big. They try and use a larger, too large in fact for best power, main jet to help compensate for a very lean idle mixture. As you can see from the popping that every stock jetted Vmax is plagued with, it's not a very good compromise. This is what we're attempting to fix. Now, this air jet I just mentioned is the same size (not the hole, but the physical size and the threads) as the main jet. That's why I told you guys to get 95 main jets. But Yamaha probably doesn't have a listing for a main of that size. Soooo, what you do is just order a 95 'pilot air jet,' because that is what it really is. You'll see when you get it that it's the EXACT same as your new main jets, just a number 95 and not a 145. The other 'pilot air jet' is called PAJ2,,, meaning 'pilot air jet number 2. It has an effect through the midrange before the jet needle takes over. This also is the same size as a main jet and that's also why I told you to get a 160 main jet. We just won't be using it in the main jet location. In this case, the stock jet (PAJ2) is a 170 and we are going to a 160. When fuel jets get larger, it means you're going richer. When air jets get larger, it means you're going leaner. Because fuel jets let in raw gas and air jets let in air. Basically, more fuel= richer,,, more air= leaner. What we really are dealing with is:

4 main jets in the size of '145' (3G2-14231-29-00)
4 pilot fuel jets in the size of '42.5' (4G0-14142-42-A0)
4 pilot air jets number 1 (PAJ1) in the size of '95' (3G2-14231-19-00)
4 pilot air jets number 2 (PAJ2) in the size of '160'" (3G2-14231-32-
00)

In addition you may also need the jet block gaskets (3JB-14199-00-00) depending on the age of your bike and the condition of your current gaskets.

Shane

Nimalex?
 
You can compare to some of our other members in high altitudes:

Current setup at 5280' Broomfield, Colorado:

(Setup has flawless carburetion going from the Denver Metro area all the way up to Mt. Evans at 14,000'+ altitude)

I get about 145-150 miles before low fuel light comes on.
Stock box with stock air filter. Modified with half-moon piece cut out of box top for better breathing at high end. 'Y' piece is on box top.
Stock 2001 Vmax exhaust (non-modified).

main jets = 145 Mikuni
pilot fuel jets = 42.5
pilot air jets number 1 (PAJ1) = 95
pilot air jets number 2 (PAJ2) = 170
(I tried running 160's on PAJ2's but lost my crisp midrange throttle response)
Stock needles (no shims)
Stock (non-drilled) slides with Dynojet springs from a Stage I kit
Idle fuel screws out about 1.5 turns each

All the sync ports are tied together on all 4 carbs with vacuum hose for a smooth idle.

I run Denso COP's with a stock 2001 ignitor box.

Perfect starting in all weather and temps. I use the choke/idle enrichment for about a minute on cold starts. Great midrange throttle response. I can consistently pull 135mph with no low, mid, or high end hiccups. I've hit 142.7mph with this setup at about 7000' altitude.

Vinnie

Here is another one from a morley muscle kit user
Well folks, this post is gonna wrap up the Adventure.

So here are my final settings.

Mikuini Mains-140 (4,300ft)
Paj 1,2-stock
Needles, Stg 7-3.5 clips from blunt.
Stock slide holes and stock slide springs.

Bike has run great since the fine tuning is complete.
I was amazed the other day I took a highway ride and the light came on @ 137 miles. Best I have ever got, so far.

Bike has quit burning that slight bit of oil it used to between oil changes.
Start up now requires a bit of choke sometimes (a good thing) but rides great after start up.

Dyno was a bit low but I am at 4,300ft. 107hp/72tq we all suffer up here.

My only gripe was the "Pex" pipe.
I let it do its thing and it completely melted on me, totally blocking the ventilation it was supposed to create?
I have since switched to a black (heat resistant) hose picked up at the local parts store.

So If you want a air/jet kit that will shock you into thinking you have a whole new bike I strongly suggest the Morley kit.....

Thank you and good night.

VmaxID
 
Thanks, I'm still unsure how much my pipes change those jet numbers though. It leaned out far too much after the exhaust system, the 155s seem to have corrected that, which contradicts the main jet changes they suggest for these stock systems at altitude.
 
A lot of times people will confuse rich....with lean....because rich is smooth. The directions for setting up the dynojet kits.....are super rich....and people are fine with that.....until they get to a dyno and find out that they've lost 15 hp.



Sent from my SCH-R890 using Tapatalk
 
See this is the problem I have, everyone has a different opinion, I'm looking for the person who knows what I need for MY setup.. Mike, after I put on the UFO 4-2-1 pipes it was way too damn lean, the one guy said up it to 155, beyond that he had no recommendations short of a stage 7 (which I don't want to do). He also said at lower altitude with my pipes I should take a set of larger jets with me if I'm road tripping or change them before I leave. Dragmaxster confirmed that one!

I'm wondering what I should do to the other jets to make it perfect.
 
OK. ...look at it this way...fact...on a motorcycle with aftermarket exhaust and cv carbs you will run richer...not leaner. On an automobile you add headers and a good exhaust...you will run leaner because because those carbs flow a set amount of air....600 cfm. ...750 cfm...etc. cv carbs don't act like that. With an aftermarket motorcycle exhaust you flow more air out.....so you will pull more INTO THE CARBS...and with that you will pull more fuel making you RICH. You have to understand that before you can jet cv carbs. Plus...the higher in elevation you go...you have to jet leaner due to elevation . Beyond that....you will have to experiment because every bike is different. There have been some good recommendations. ..it's up to you if you follow them. Also.....you have a main fuel jets......and 2 primary air jets....which you can also change... but make it easy on yourself and don't because you don't have to. Also the A/F screws also act as a tuning tool and cover from 0-4000 rpm at 1/4 throttle on the vmax.

If you want the perfect set up and don't want to mess with the bike....you might need to find a tuner...and drop the bike off.....pay them.....and pick it back up.

People on here have told you to go leaner the higher up you go.....if you don't want to follow the advice...that's up to you....but there are people on this forum that routinely dyno their bikes.


Sent from my SCH-R890 using Tapatalk
 
See this is the problem I have, everyone has a different opinion, I'm looking for the person who knows what I need for MY setup.. Mike, after I put on the UFO 4-2-1 pipes it was way too damn lean, the one guy said up it to 155, beyond that he had no recommendations short of a stage 7 (which I don't want to do). He also said at lower altitude with my pipes I should take a set of larger jets with me if I'm road tripping or change them before I leave. Dragmaxster confirmed that one!

I'm wondering what I should do to the other jets to make it perfect.

Don't they still rent out bandimere on the weekdays?
 
I ride the palms to pines road behind my house that goes from the california desert to the pacific ocean in san juan capistrano. It is known as biker heaven. It is 125 miles and is hiway 74, ortega hwy. From my house at below sea level to idillwyld at 5500 ft
(that's higher than denver) i ran stock pipe K&N single filter 152.5 main jets with 100 air jet. The jets in the jet block were all stock also. a/f 2 1/2 turn out. Drilled pipe but that just made it louder-not much more airflow. You could feel the difference in pull go away as the altitude increased as we all know.

If you are going to stay in denver your setup should be-
145 mains
42.5 fj
paj1-100
paj2-175
a/f-#2-2 turns out
a/f-#1-2 1/4 turns out
sync carbs first after jet change then set a/f mixture screws
 
I ride the palms to pines road behind my house that goes from the california desert to the pacific ocean in san juan capistrano. It is known as biker heaven. It is 125 miles and is hiway 74, ortega hwy. From my house at below sea level to idillwyld at 5500 ft
(that's higher than denver) i ran stock pipe K&N single filter 152.5 main jets with 100 air jet. The jets in the jet block were all stock also. a/f 2 1/2 turn out. Drilled pipe but that just made it louder-not much more airflow. You could feel the difference in pull go away as the altitude increased as we all know.

If you are going to stay in denver your setup should be-
155 mains
42.5 fj
paj1-100
paj2-175
a/f-#2&#3-2 turns out
a/f-#1&#4-2 1/4 turns out
sync carbs first after jet change then set a/f mixture screws
The interesting thing about that set up. Your richening up the mains.....and then leaning out everything by letting in more air by changing out the air jets. Most people don't change all the variables.

Sent from my SCH-R890 using Tapatalk
 
The interesting thing about that set up. Your richening up the mains.....and then leaning out everything by letting in more air by changing out the air jets. Most people don't change all the variables.

Sent from my SCH-R890 using Tapatalk

I meant 145 mains- sorry.
 
OK. ...look at it this way...fact...on a motorcycle with aftermarket exhaust and cv carbs you will run richer...not leaner. On an automobile you add headers and a good exhaust...you will run leaner because those carbs flow a set amount of air....600 cfm. ...750 cfm...etc. cv carbs don't act like that. With an aftermarket motorcycle exhaust you flow more air out.....so you will pull more INTO THE CARBS...and with that you will pull more fuel making you RICH. You have to understand that before you can jet cv carbs. Plus...the higher in elevation you go...you have to jet leaner due to elevation . Beyond that....you will have to experiment because every bike is different. There have been some good recommendations. ..it's up to you if you follow them. Also.....you have a main fuel jets......and 2 primary air jets....which you can also change... but make it easy on yourself and don't because you don't have to. Also the A/F screws also act as a tuning tool and cover from 0-4000 rpm at 1/4 throttle on the vmax.

If you want the perfect set up and don't want to mess with the bike....you might need to find a tuner...and drop the bike off.....pay them.....and pick it back up.

People on here have told you to go leaner the higher up you go.....if you don't want to follow the advice...that's up to you....but there are people on this forum that routinely dyno their bikes.


Sent from my SCH-R890 using Tapatalk

Good explanation Eric! :thumbs up:
 
I'm using the 145 mains at 3500' and loving it. I had the stage 1 kit which was obscenely rich, rich enough to miss and stumble on the main jets. I still have the stage one needles installed at the leanest mark and it runs great. I'll see between 30 and 40mpg depending on conditions and it now runs amazing.
 
I raced the nhra circuit around the usa and canada going from gainesville at 120ft to bandimere at a mile high and the rule of thumb for JUST the altitude change was to change mains every 1000ft then calculate the rest from there. Many more factors involved though as i'm sure you know.
You gets increments of 2.5 w/mikuni and 2 w/keihin for the mains.
Dyno jets are measured in mm's as are precision engineering-dyno being .02 and pe being .025.
Start with the main jet as a rule of thumb below-
Get the engine rpm high enough that it is on the cam and in its power band. This may need to be as high as 4000 rpm with some cam choices. Apply full throttle. Let the engine accelerate for a couple of seconds until it has settled in and is pulling hard. Quickly roll the throttle off to about the 7/8ths position. When you do this, the mixture richens slightly for a second or so.
If the engine gains power as you roll the throttle off, then the main jet is too small and you need to fit a larger one.
If the engine staggers slightly or has a hard hesitation, then the main jet is too large and you need to fit a smaller one.
However, once you start zeroing in on the correct jetting specs, you should be basing your jetting changes based on what the bike is telling you--not what someone else (who isn't testing with you) says is right for your bike/situation. There aren't really any shortcuts to getting jetting right.
 
Here is something that is a bit more Vmax orientated. It was originally posted by Maleko89 (Mark) one helluva tuner. Its also a sticky in the carb section

Originally Posted by maleko89
You should probably be able to accept WOT in any gear above 2K w/o any bucking or complaint.

Do the following tests.

1) Cruise at 4K in 5th gear .. hold RPM steady (count to 5) and then whack it WOT as quickly as you can. You shouldn't feel the slightest delay or hesitation. If you do, too rich. This does not work at 3.5K or 4.5K, only at 4K because the slides will start to retract at 4.5K even at the lightest throttle angle. 4K sets us up on the threshold and gives us a big jump when we whack it. there is no other RPM to do this where you will get as big a slide jump when rapidly moving to WOT.
This tests for too rich of needle.

2) Verify that starting cold .. that the engine is weak .. and will complain if you try to hold the RPM at 1800 rpms. Within 1-2 min or no later than when the temp needle touches the first mark you should be able to hold the engine between 1500 and 2K w/o complaint or popping back through the carbs. At the least you should be able to do this by the time the engine is fully warmed up but if you are more than 1/2 way between the dot and cold on the temp gauge your pilots are plugged or too lean... (clean or reduce the PAJ2). If you can hold 1.5-2K as soon as you start cold then your pilots are set too rich and you will suffer rich symptoms when it comes to operating temp (clean or enlarge the PAJ2). Only change PAJ2 bigger/smaller if you mixture screws are out or in too far already.
This is how you set your pilot mixture.

3) Do a hard WOT pull in 2nd or 3rd gear from below 3K. Look for a smooth pull all the way up. If it seems to lag in the 4-5K range then too much needle. If we sputter going past 4.5K you don't have enough needle.
This tests for needle richness and leanness.

4) Verify you can cruise "nice and deliberate" at 5K .. if you stumble around and are OK everywhere else you don't have enough pilot.
Another pilot mixture test.

As for your mains, I'd at least go to 147.5's. General rule is to subtract main jet size by 1% for every 1000 feet above sea level. So, need to decrease main jet size of 152.5 by 4.5%. 95.5% times 152.5 = 145.6. I'm thinking 145's would work best at 4500 feet above sea level.
 
Here is factory Pro's guide to tuning...which is very relevant. You tune a motorcycle from the top down.

Factory Pro, CV Carb Tuning

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 highest top speed / pulls hardest 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.

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.
 
No idea about bandameir I have an OD 5th so I kind of killed the notion of racing her...

My friend with a similar setup jetted his according to the information I posted. It was too lean and cooked his engine.
 
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