02 Yamaha V Star 1100 backfiring

[tomosborne]

My 1100 did that exactly. 3 turns out on the idle air mixture and it ran silk smooth. No popping or backfire. Carbs need to come off and idle air plugs removed. Set the screws as close as you can. Install carb . Special idle screws are available so metering is more precise. You can set while running.

[Nycalboy]

My bike did the same thing. I jetted and tuned the carbs. Now she runs good.

[willebiggz]

the reason you back firing might be cause you are running to lean.. this is an easy fix.. you do not have to re jet the carbs if you are keeping the stock exhaust. you need to adjust the fuel to air mixture on the carbs.. first you would need to remove the welch plugs. then that will expose the pms (pilot mix screw) use the pms to richin up the mix.. your bike comes from the factory with the pms 2 1/2 turns out. with the bike running and warm turn the pms all the way in untill they are lightly seated and then turn them out 3 to 3 1/2 turns until bike stops poping. any more then that and you have to put bigger jets. i also would sync the carbs after your done. i know this sound like a pain in the ass but there are a few vids on youtube that will help u do this.. good luck

[mannysalazar]

I have a 2005 doing the same thing. haven't fixed mine since it just started doing it today after I pulled the carbs to replace a leaking seal on one of the carb bowls after installing running and synchronizing the carbs the bike started acting up out of the no where. I believe in my case is 1 of 2 things either I have a vaccum leak after carbs I noticed the boots are dry rotting possibly allow leaks in creating a lean effect or the only other thing is the mix screw got spinned (doubt it, but never know) I have external MaxMix air screws easy access for adjustment check em out if you don't have em already. things I noticed were the popping when letting of the gas and popping at idle constantly with a blue flame just out of one pipe (rear cylinder) what I'm gonna do next is run it a bit shoot the pipes with a temp gun a lean cylinder will run hotter also it helps that my dad has an 08 vstar easy compare temps between all cylinders see what kind of issue I have and second pull the plugs and read them to see/verify if it's a lean or rich issue (honestly guys I think I'm running lean on that rear cylinder should be an easy fix I'll report back. @ OP brother not trying to jack your post but it's the only way we can fix each other's vstar's these things are awesome but delicate as hell in the fueling department.

[bvgb]

When you put after market pipes on a dragstar you need to disable the AIS system as it's no longer required, leaving it in place will cause your bike to backfire. The AIS is only needed for the stock exhaust, it pumps air in to the cylinder heads when the exhaust valves open to help burn the gases that get trapped due to the catalytic converter within the exhaust, as your after market exhausts don't have catalytic converters fitted you no longer need this process to happen.

[TheLordbal]

looking deeper into the scoot i found that i had a loose spark plug wire not fully seated onto the plug, once i secured it the popping had greatly diminished, still there a lil bit bit almost not. check ur connections peeps. ;)

[bryannoble]

I started my bike up after sitting all winter and now it does this but from only the front cylinder.

[bobe]

You could check your valve adjustment but sounds like air getting in some where. I personally do not like noisy after market pipes. They take too much setting up at the carbs and you have to get the jets spot on or there will be problems.

[rudymacias]

Sync the carbs. That is your problem. I did a lot of research syncing the carbs fixed it.

[TheLordbal]

A bunch of biker friends told me that it is normal for some bikes to do that, also said I shouldn't worry about it. Also noticed a lil flame coming out of the pipes, will not harm the bike at all.

[DanBlackRacing]

Tighten all your exhaust pipe connections (5 min). Get your carbs synced and TPS adjusted.

[phill]

I had the same issue .The other mager thing that can cause this is a vaccum leak and the rubber inlet manifolds that hold the carbs to the heads they are prone to cracking or splitting id start there before you touch anything else as i had a small split that i couldnt even see so i got a new one and it stopped straight away

[tomosborne]

Static compression test cold may be 160 lbs throttle open wide ignition wires disconnected. The 10.6 pistons can give up to 200 lbs.

[tomosborne]

All other thoughts below are good points. It can have a plugged carb jetting. Many other things

[rickwoods]

It is the rubber on your carburetor mounts you should replace both of them you will see cracks in the rubber

[danielocallaghan]

I had moisture in the gas. Once the tank was near empty, it happened a lot so I let the tank run dry. Refilled the tank with fresh gas, added some Seafoam and she runs great again. Still the odd popping and burping, but almost par for the course for a Vstar.

[bikerclivew]

Hi bud, just came across your video. My bike is sounding exactly the same! Did you find the problem? Merry Christmas 🇬🇧

[pepelepew]

i got exactly the same problem on a 2005 and i thought the same thing you point out on the pipes mine is smoking on the conection!

[geezermoto]

Intake manifolds crack on vstars, sucks air, too lean, backfires. Same with air cut off valve. Strip and vat carbs, new cut off diaphragms and new manifolds, a couple rebuild kits, your good.

[jerrypeal]

Did you sync your carburetors, mine did that until I did mine . I’d check