Honda Shadow 1100 Carburetor Jetting

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One of easiest ways to get more power out of a bike is to open up the restrictive stock exhaust and intake. The Honda Shadow 1100 is no exception. In fact Kerkers, a K&N and a jet kit will make this bike much more fun to ride and smooth out the throttle response so much that you'll think it's a new bike.

Jetting the bike isn't hard, but it does take some care. It's possible to try and tune the carbs yourself, however, you will probably save your self a lot of time by just buying a jet kit for it from somebody who has already spent the time and research to get the mods right. You can save a few bucks if you want to try and grow your own jet kit. It all depends on how valuable your time is to you and if you'd rather be riding, or jetting. Depending on the age of your bike, you may want to have an impact screwdriver on hand. The phillips head screws in japanese carbs can be a real pain to coax free if they've been around for a while. Big point.. NO SMOKING DURING THIS JOB!!! Beer may be consumed in place of smoke. Use your own judgment on that. But.. NO SMOKING!!! The seat is the first item that should be removed. It's not hard. There are three bolts that hold the seat in place on this bike, one on the back and two on the sides.

Remove the rear seat bolt.

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Remove the two side seat bolts.

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Once you have the seat off, it's time to work on the tank. There is a small bolt at the front of the tank that needs to be removed.

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Remove the rear tank bolt.

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Make sure you turn off the fuel and remove the fuel line.

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There is a vent hose on the right rear of the tank will have to come off as well. Sorry, I don't have a pic of it, but you'll notice it when you try and lift the tank off the bike. It will be easier to lift the tank if there isn't much fuel in it... so plan ahead and either drain the fuel out or run it till it's almost empty. Now you will see a mass of wires, hoses, cables and assorted plastic bits where the carbs should be. It's time to start removing stuff.

The mysterious area under the tank.

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Left side view of the carbs.. an you see em?

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Right side view of the carbs.

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Remove the resonating chamber, or is it a crankcase vent chamber?..hmm doesn't matter.

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Remove the two hoses from the chamber.

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Loosen the intake snorkel clamps.

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It's a tight fit. If you follow the end of the screwdriver in, you can see the gold colored clamp.

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More screws....

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With the snorkel removed, you can see the tops of the carbs.

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Remove the fuel inlet line.

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Remove the throttle cable mounting braket, cables and choke valve.

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Loosen the carb boot clamps.

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Note that there is a choke (enrichening valve) for each carb. You can see them sticking out of the carb with a cable attached. You should now be able to carefully loosen the carbs from the boots and wrangle the unit out of the frame. I was able to remove them from the right side of the frame. Make sure you don't knock anything into the intake boots while removing the carbs. If you do, you'll have to retrieve it, and if it's small enough, it may fall into the cylinder. Now that the carbs are out it's time to install the jet kit. The first thing you should do is dump the fuel out of the float bowls. Hold the carbs over a bucket or something and move the carbs around at all angels.. the fuel will run out. Once that's done you can start by removing the cv cover. Note that it only goes on one way.

Remove the CV cover.

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Gently pull the rubber away from the carb and pull the slide out.

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Look down in the top of the slide and you will see a keeper that needs to come out in order to remove the needle. Use a screwdriver to turn it counter clockwise and then it should come out.

Remove this piece from the slide.

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This is what you should see.

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Replace the needle following the instructions provided with the jet kit. Use the clip in the recommended slot and replace the washers in the correct order.

You can see the difference between the needles.

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Reinstall the plastic keeper in the slide. Very carefully replace the cv cover. Remember it and the slide only go in one way. Make sure you use the new cv springs included with the kit.

Pay attention to this tab. The slide and cover go on one way only.

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Next, remove the screws that hold the float bowl on, unscrew the main jet and replace it with the one from the kit.

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Replace the float bowl. The jet kit should come with a drill bit and a sheet metal screw that is used for removing the caps over the idle air mixture screw. After removing the cap, then adjust the air mixture screw to the specs in the kit.

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Replace everything you removed in the same order you removed it, and you are done. Now to ride the beast and see the improvements. I'm not really a cruiser enthusiest myself. If it's your thing then that's cool. I dressed up in my full leathers complete with knee sliders and went for a "cruise". The bike had a noticeable amount of extra juice. A hill I had crested before at about 90 was easily crested doing a tad over 100. I'd guess it had about 6 or 7 more horses at it's peak. The biggest thing that was noticed though was how smooth the throttle response was. Before, when you would blip the throttle for a down shift or try and rev match the bike it would hesitate and fumble around. NOw it was smooth as butter. The exhaust note and the K&N actually made the bike more fun to ride. I felt like a rebel terrorizing the town. While I wouldn't trade the Shadow for an RC, I'd consider swapping this bike for a day or so. The mods really did increase the grin factor enough to make it fun for me.

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Comments

JETTING

DAVID
I JUST FOUND YOUR SITE TONIGHT AND IT IS BY FAR THE BEST INFO I'VE SEEN ON JETTING.
I OWN A 97 HONDA SHADOW ACE WITH 14M MILES. HAD ABOUT 1YR. PREVIOUS OWNER TOOK OUT BAFFLES IT HAS ALWAYS RAN WELL BUT NO POWER OR THROTTLE RESPONSE AND I'M TOLD RE-JETTING SHOULD HELP. I READ YOUR INFO AND FEEL LIKE I CAN DO THIS. MY QUESTIONS ARE
1. DO YOU FEEL RE-JETTING WILL HELP
2. WHAT BRAND OF JETT DO YOU SUGGEST AND STAGE
3. AND WHAT ABOUT A KN AIR FILTER. SOMEONE SAID THIS WOULD HELP

I JUST WANT THE POWER THE BIKE DESERVES

I GREATLY APPRECIATE YOUR HELP AND ADVICE

RIC
MEMPHIS TN

dpotts's picture

Jetting it should make an

Jetting it should make an improvement. Most carbureted bikes come rather lean from the factory. Removing baffles and or de-restricting the intake make them run even leaner. Dynojet are the kits I've used unless I'm rolling my own. I think for the Ace they only make one kit, which should work fine unless you're going to drop some cams and do some porting. In that single kit it provides for enough adjustment to handle most tuning needs. I'd go with a K&N too.

jetting issues

great breakdown on how to jet!! i have a 97 shadow spirit 1100 and i wanted to do some mods. so i installed hard chrome exhaust with baffels,, k/n air cleaner and a dyno-jet carb kit.the kit was easy to read and install but every since these mods i have no top end...the bike just falls on its face and it cruises with the sensation that its trying to hold itself back..the dealer said its the side affects of straight pipes but i find it hard to believe cuz the cleaner and kit are made to compinsate.. if you have any ideas or little tricks up your sleave that might help ,, i would sure be appreciative before i take this stuff back off..thanks

dpotts's picture

I know I'm way late

I know I'm way late responding to this. There could be any number of things causing the loss of top end. My first guess would be that the K&N has opened up the intake a bit more than the carb kit was designed for. Raising the needle and or using a larger main jet might help. I'm just guessing though. Without the bike being here it'll be hard to know for sure.

easy mods for stock 95 VT1100C

I picked up a 95 shadow that appears to be all stock. I'd like to see if I can get any increase in anything (low or high end torque). Can I get any improvements by replacing the air filter and rejetting alone (with no exhaust replacement or by modifying the stock exhaust)? Also, what are the Kerkers you refered to (slip-ons, 2-1 full exhaust?) Sorry for my ignorance of the lingo.

A couple notes: This is the only shadow i've ever been on so I don't have a frame of reference but I don't notice any "blips" you mentioned. However, I do notice (in addition to overall lack of power) that I get next to zero torque in upper midrange to high RPM (it basically just revs with no power gain from rolling on the throttle at midrange RPM).

As a side question: The first thing I noticed when picking up the bike is the engine breaking (holy cow, I barely have to use the breaks), during which it sounds like the resonator (or whatever is in there) really goes to town (sounds like a semi engine breaking). Is this normal?

dpotts's picture

Yes, replacing the air filter

Yes, replacing the air filter and/or opening up the airbox to get more flow along with rejetting will get you some power improvements. An exhaust replacement isn't necessary. I honestly can't remember if the Kerker exhaust on that bike were slip ons or full exhaust.

Blipping the throttle refers to a quick twist of the throttle and then releasing it to rapidly bring the revs up. Usually it's done during a down shift to match the rpms with the next lower gear ratio in order to avoid the massive engine braking you noticed from making the rear tire slide as the clutch is released.

These engines are not designed to make much more power above the mid-range. They're tuned for very low end torque and power. The only way to get them to make more power at the top end would be to install some different cams. But, doing so would most likely make the engine less reliable since the internal components, pistons, valves etc are not designed to take the abuse of the higher rpm ranges.

Massive engine braking is normal from this engine. With most v-twins, rear brakes are optional.