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Discussion Starter #1
I have a 97 Classic and it needs minor love. New fuel / Vacuum lines, fuel sensor, turn signals. Replacing old plugs and wires. All fluids to be changed. Added MAC Fat Stakker pipes.

Pulling off the dog bowls and cross over tube and adding a bigger air intake. Kuryakyn Pro Hypercharger.
Anyone added one of these that may add info. Ad says the kit comes with jets. Form what I’m learning (I’m a newb) one has to figure out the best jet size by trial and error.
How do I know when “perfect” is?
Besides changing jets 12 times.

Thanks folks,
Lonestar
 

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Discussion Starter #2
The build continues:

Pulled Dog bowls and cross pipe out.
Pulled Intake manifold Boot- had a chip-ordered new w/O rings
Ordered new Fuel pump and filter kit.
Ordered 6 ft Fuel and vacuum lines.
Ordered new turn signals front (already replaced rear)
 

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I have a 97 Classic and it needs minor love. New fuel / Vacuum lines, fuel sensor, turn signals. Replacing old plugs and wires. All fluids to be changed. Added MAC Fat Stakker pipes.

Pulling off the dog bowls and cross over tube and adding a bigger air intake. Kuryakyn Pro Hypercharger.
Anyone added one of these that may add info. Ad says the kit comes with jets. Form what I’m learning (I’m a newb) one has to figure out the best jet size by trial and error.
How do I know when “perfect” is?
Besides changing jets 12 times.

Thanks folks,
Lonestar
Sorry, there isn't a one size fits all approach. Jetting depends on where you ride, how you ride, the humidity, altitude, the motorcycle itself.

I can tell you that there are lots of guys who will tell you "all you need to do is _____", but it seldom is the case that what works for a cautious 65-year-old retired accountant in the Phoenix suburbs will work the same for a 27-year-old speed demon living in the mountain twisties. They ride for different reasons in different places, so the requirements are different. It also depends o0n whether you're looking for low w end power or top-end cruising efficiency. It seems to be the nature of V-twin cruisers that you can have one or the other, but not a huge amount of both.

My advice is to first, don't make multiple changes at once. Take them one at a time so that you can see if each change makes things better or worse. Multiple changes make it hard to determine what caused the changes, and you can get fouled up really fast and have to start all over. Guess how I found this out?

Also, small changes make a big difference. I've seen guys jump 10 notches on their main jets and go with way big pilot jets (stock is 42 in my 1500, some guys jump to a 48 or 50 and then say it runs great, but now they're only getting 32 mpg and they just wish it got better mileage.) Guess how I found this out?

This brings us to jets themselves: different manufacturers of jets use different numbers to indicate the sizes for the same jets. Thus, a Keihin (stock carbs in Kaws) 138 stock main jet is a 128 in a Dynojet and a 120 in a Mikuni. Here's a handy chart to show you what I mean.


When I got my jet kit, I heard all kinds of guys on forums talking about going with a 170 main. So I ordered a kit from Dynojet and put the 170 main in. Only it turns out that Keihin calls the same jet a 190, WAY too big. The bike ran so boggy it would barely accelerate. I called an old retired Japanese bike mechanic I know and he said he only bumps up mains one or two increments at a time. So I pulled the 138 main and with various different jets until I settled on a Dynojet 140, which is a Keihin 152. Because I live and ride almost exclusively between 2200 and 6000 feet, and I live in the foothills of the Rockies, we have a lot of mountainous terrain and thinner air. So I need less fuel than someone living at 90 degrees and sea level. After a bit of trial and error, I went t with a 45 pilot jet and the 140 Keihin main. I bought an EZ-Just mixture screw so I can reach back and turn the fuel-air mix as needed. Today, the bike runs like a champ but I get about 45 mpg average with it.

I'm more interested in top-end performance and cruising comfort than I am low-end torque. I'm not going to be doing much drag racing or sudden acceleration bursts. But tuning a bike depends on what you're after, a consideration lots of guys don't think about when they start. They just want to sound good and perform decently, but don't consider that the set up for distance cruising is different than for errand hopping. Anyway, hope this helps!
 

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Discussion Starter #4
Hey Patrick,

Sir thank you so much for your info!

Will keep this thread up to date on progress.

Appreciate ya buddy!

Lonestar
 

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Discussion Starter #5
The build continues:

Pulled Dog bowls and cross pipe out.
Pulled Intake manifold Boot- had a chip-ordered new w/O rings
Ordered new Fuel pump and filter kit.
Ordered 6 ft Fuel and vacuum lines.
Ordered new turn signals front (already replaced rear)
8/2
Pro Series Hypercharger Kit - 9404 - arrived missing EZ adjust in the same shipment- Denniskirk.com sending another asap. (Great service)
This is a fairly hefty hunk of intake- seems well built- We'll see how the install goes.
https://www.denniskirk.com/kuryakyn/pro-series-hypercharger-kit-9404.p304434.prd/304434.sku
 

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Discussion Starter #6
Kuryakyn Pro Hyper Charger install. - QUESTION

Sorry, there isn't a one size fits all approach. Jetting depends on where you ride, how you ride, the humidity, altitude, the motorcycle itself.

I can tell you that there are lots of guys who will tell you "all you need to do is _____", but it seldom is the case that what works for a cautious 65-year-old retired accountant in the Phoenix suburbs will work the same for a 27-year-old speed demon living in the mountain twisties. They ride for different reasons in different places, so the requirements are different. It also depends o0n whether you're looking for low w end power or top-end cruising efficiency. It seems to be the nature of V-twin cruisers that you can have one or the other, but not a huge amount of both.

My advice is to first, don't make multiple changes at once. Take them one at a time so that you can see if each change makes things better or worse. Multiple changes make it hard to determine what caused the changes, and you can get fouled up really fast and have to start all over. Guess how I found this out?

Also, small changes make a big difference. I've seen guys jump 10 notches on their main jets and go with way big pilot jets (stock is 42 in my 1500, some guys jump to a 48 or 50 and then say it runs great, but now they're only getting 32 mpg and they just wish it got better mileage.) Guess how I found this out?

This brings us to jets themselves: different manufacturers of jets use different numbers to indicate the sizes for the same jets. Thus, a Keihin (stock carbs in Kaws) 138 stock main jet is a 128 in a Dynojet and a 120 in a Mikuni. Here's a handy chart to show you what I mean.


When I got my jet kit, I heard all kinds of guys on forums talking about going with a 170 main. So I ordered a kit from Dynojet and put the 170 main in. Only it turns out that Keihin calls the same jet a 190, WAY too big. The bike ran so boggy it would barely accelerate. I called an old retired Japanese bike mechanic I know and he said he only bumps up mains one or two increments at a time. So I pulled the 138 main and with various different jets until I settled on a Dynojet 140, which is a Keihin 152. Because I live and ride almost exclusively between 2200 and 6000 feet, and I live in the foothills of the Rockies, we have a lot of mountainous terrains and thinner air. So I need less fuel than someone living at 90 degrees and sea level. After a bit of trial and error, I went t with a 45 pilot jet and the 140 Keihin main. I bought an EZ-Just mixture screw so I can reach back and turn the fuel-air mix as needed. Today, the bike runs like a champ but I get about 45 mpg average with it.

I'm more interested in top-end performance and cruising comfort than I am low-end torque. I'm not going to be doing much drag racing or sudden acceleration bursts. But tuning a bike depends on what you're after, a consideration lots of guys don't think about when they start. They just want to sound good and perform decently, but don't consider that the set up for distance cruising is different than for errand hopping. Anyway, hope this helps!

Update-
After speaking with Carl at C&P Cycles (Tech Mechanic) and looking at the setup that worked well for Patrick at 2000-6000 FT (Colorado) As I live in the Dallas area (600 ft Above sea level) we decided to start at a 50 main jet (ordered a 60 as well as they're $3) and ordered a 142,145,148 pilot jets.
Installed new fuel pump and filter. They worked fine but did not cost much and I'm looking for serious reliability and had it all open so why not.
New front turn signals and the Hypercharger is assembled and will mount.

QUESTION: - Can I install jets, run for 30-40 miles, check plugs looking for white, tan, or black and change jets accordingly without the Hyperchager (open carb) and then add it back on after?
The Hyperchager seems to be pretty unrestrictive. The main jet is used mostly for low throttle (highway etc)
I'm unsure just how much air increase there is as the scoop nature of the Hypercharger effect will apply at speed.
 

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The carb works so that the first third of the throttle range is mostly pilot jet, the second third is a variable mixture of pilot and main, and at highway speed, you're mostly running on the main.

I get a lot of flak for telling folks this, but it's true: if you look at your hyper charger, there is likely an exit slot or hole to the rear of it. This is to help keep water from being scooped into the carb and instead forced out the back. I love the look of them, and I tried one, but my legs are such that I kept banging my right knee on it so I went with a Baron's that sits closer to the motor out of the way.

All that is to say I don't think your hyper charger is going to affect the air volume much more than any other aftermarket hi-flow air system. As for running it without an air kit to test it, it should be fine. I put a piece of pantyhose over the carb opening with a rubber band to keep the bugs and stuff out when I test ride.
 

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Discussion Starter #8
Thanks folks,
Patrick you’ve been a big help.

Looking to wrap it up this weekend.
Will test and check jet sizes.
 

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Discussion Starter #9
Seems I need a different Emulsion tube.

All of the main jets I purchased do not fit the emulsion tube. GRRRRRR.
 

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That's weird. Mine just screwed right in. I'd also urge you to put a dab of blue loc-tite on the main. Once when I was fiddling with the jets I took it out for a spin and all of a sudden it bogged down really bad and started bucking and it finally died. Fortunately, I was half a block from the house so I pushed it home. Pulled the carb and the main jet had vibrated out and was laying in the bottom of the float bowl.

I don't know about ordering jets. I ordered my first rebuild kit from Dynojet when I did my pipes and air, but generally, I just go to a motorcycle shop and buy jets singly. Since the numbers vary by manufacturer, I take my needle with me, and the jet I'm replacing, and then I look to see how far the needle goes into the new jet compared to the older one. This method, while unusual, worked out for me. They cost about 4 or 5 bucks. My Honda dealer carries them, the HD dealer carries them and most sportbike/snow sled or ATV places carry them. They may have the part you need too. Or you could pull the emulsion tube and take it to a dealer/shop and see if they have any jets that fit. We are blessed with a place called "Recycled Cycles", which is a wrecking yard for bikes and they also fix them up and resell them. They dip cleaned my carb for 40 bucks. But they have parts for pretty much everything except the newest bikes.
 

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Discussion Starter #11
Yeah, I’ve tried several jets for the main and none thread. Odd. I tried to call support today at J&P Cycles and the recording had some lame excuse about a hurricane
😂😂😂😂. I hope all fair we’ll from Dorian.

When they reopen a guy named Carl seems to know his trade well. I see what his input is.

Thanks for the lock tight advise

Lonestar
 

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Yeah, I’ve tried several jets for the main and none thread. Odd. I tried to call support today at J&P Cycles and the recording had some lame excuse about a hurricane
😂😂😂😂. I hope all fair we’ll from Dorian.

When they reopen a guy named Carl seems to know his trade well. I see what his input is.

Thanks for the lock tight advise

Lonestar

Yep. The loc tite was because the aftermarket ket was k just a fuzz undersize on the threads. As you are finding out, they arentl always exact.
 
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