Yamaha Starbike Forum banner
  • Hey everyone! Enter your ride HERE to be a part of this month's Bike of the Month Challenge!
1 - 20 of 24 Posts

·
Registered
Joined
·
7 Posts
Discussion Starter · #1 ·
I bought my 02' vstar 1100 about 2 weeks ago, and I was noticing that it would backfire during deceleration. So after reading several threads, i decided to have it jetted and add a hypercharger and have the AIS plugged.
Now it has lots of power but it backfires even worse than before.
Does anybody have any ideas?
 

·
Registered
Joined
·
6 Posts
I bought my 02' vstar 1100 about 2 weeks ago, and I was noticing that it would backfire during deceleration. So after reading several threads, i decided to have it jetted and add a hypercharger and have the AIS plugged.
Now it has lots of power but it backfires even worse than before.
Does anybody have any ideas?
My VStar 1100 07 backfired right after I installed the Hard Krome slip-ons. After reading posts I learned that I needed to remove/plug the AIS. Once that was done the backfires stopped. Do you have after-market pipes and if so was the AIS plugged correctly? Also look for an exhaust leak that is sucking cold air in on deceleration.

SS
 

·
Registered
Joined
·
7 Posts
Discussion Starter · #3 ·
I have vance and hines pipes, My mechanic plugged the AIS with a golf tee near the tool pouch. Is that the right place? I'm trying regular gas like someone suggested, I've only got about 20 miles on this 87 octane but it does seem to backfire less I'll test it with a couple of tanks before I go into other things.
Thanks.
 

·
Registered
Joined
·
6 Posts
It is possible that your mechanic did not complete the AIS disable/removal. This was easy to do. I got all the parts and tools, took about an hour. At the bottom of the PDF he shows a "lazy" way to bypass the AIS. I did this first to test it and no backfire so I completed the removal.

I used this PDF by John A. Klopfenstein http://www.sloneservices.com/SilverBack/Other-Stuff/AIS Removal.pdf to remove mine and it worked PERFECTLY.

Please read it completely as it is VERY good.
 

·
Registered
Joined
·
21 Posts
What jet kit did they use and how much is the primary metering screw (pms) turned out on both carbs? Most dealership mechanics don't understand how to jet the 1100 carbs right, so they use the Cobra jet kit aka dyno jet kits (which are junk in my "opinion"). Plus the carbs need to be synchronized right after the carbs are jetted. To determine the main jets, the mechanic needs to know your elevation. If he does not know the elevation were you live, your carbs are not jetted right.

For me, I only use Mikuni jets. Here is my set-up. My bike has one K/N air filter (POD kit) per carburetor and I'm running full length exhaust (Bud Big Willy's).

My elevation is about 800 feet above sea level, so I had to use 150 main jets.
~Main Jets - 150
~Pilot Jets - 22.5
~Two .020 (.5mm) shims on each needle.
~I'm still using the stock Mikuni needles.
~The Primary Metering Screws (PMS) are turned out 3 full turns.

For one thing, if your bike is popping/backfiring during deceleration, your pms is not turned out enough or you have a vacuum leak. Meaning your bike is running lean.
 

·
Registered
Joined
·
21 Posts
I have vance and hines pipes, My mechanic plugged the AIS with a golf tee near the tool pouch. Is that the right place? I'm trying regular gas like someone suggested, I've only got about 20 miles on this 87 octane but it does seem to backfire less I'll test it with a couple of tanks before I go into other things.
Thanks.
Putting a gulf tee in the AIS hose is the wrong way to disable the AIS. The AIS needs to be taken completely off the bike. Just remember, the chrome tubes for the AIS will hold moisture and rust out over time.
 

·
Registered
Joined
·
4 Posts
2005 v star exhaust popping

new here,,,just bought a 2005 v star 1100 6 months ago,,,ran nice but needed more sound...baron slip ons was installed and i guess the troubles began....it seems to pop when i sometimes shift from first to second gear....also if its just sitting there and warmed up,,,just give it a little rev and it will pop when i let of the gas...not all the time,,,but enough were it bugs the crap out of you.....i dont really know anything yet on bikes yet,,,all new to me....i did have old hot rod cars that we did alot of street racing and stuff.20 years ago we ran 9s and 10s on the street/track...so i know a little i think about the plugs.....i pulled the plugs and to me,,they dont look bad at all...new exhaust gasket and even sealed the muffler to the exhaust pipe with hi-temp sealer...still no difference....carbs are stock and havent been messed with....the guy at the dealership said its either un burnt fuel or its a lean back fire....when i cruise around town and highway,,,it runs great...would appreciate any help....thanks guys
 

·
Registered
Joined
·
1,531 Posts
Popping

This is one of the most talked about topics on many Forums. It is hard for a reader like me to know how much or how loud the popping actually is but consider these.

Some things to think about that you probably know but just in case. The popping is unburned gas being ignited in the exhaust from the heat. When you "free up" the exhaust it gets a little worse. Air cooled V Twins seem to be intentionally run a little rich.

AIS (Air Injection System) injects a little air in the exhaust to burn off unburned gas and reduce emissions. So often after "freeing up" the exhaust, maybe eliminating the catalectic converter in newer bikes a little more popping occurs. Removing and plugging AIS helps some by eliminating oxygen in the exhaust.

Me I think a little low level popping is normal and even like it a little at times, like when engine braking going down a long hill. Does anybody remember the days of the old V eights with glass packs popping if you ran them up tight and let off allowing it to decelerate in second gear. (Before the days of emissions controls.) Lots of popping and cracking, and there were no AIS in those days. Just raw gas getting through to the exhaust.

I am sure the right fuel air mix has a lot to do with it.
Dave
 

·
Registered
Joined
·
6 Posts
Poppng

new here,,,just bought a 2005 v star 1100 6 months ago,,,ran nice but needed more sound...baron slip ons was installed and i guess the troubles began....it seems to pop when i sometimes shift from first to second gear....also if its just sitting there and warmed up,,,just give it a little rev and it will pop when i let of the gas...not all the time,,,but enough were it bugs the crap out of you.....i dont really know anything yet on bikes yet,,,all new to me....i did have old hot rod cars that we did alot of street racing and stuff.20 years ago we ran 9s and 10s on the street/track...so i know a little i think about the plugs.....i pulled the plugs and to me,,they dont look bad at all...new exhaust gasket and even sealed the muffler to the exhaust pipe with hi-temp sealer...still no difference....carbs are stock and havent been messed with....the guy at the dealership said its either un burnt fuel or its a lean back fire....when i cruise around town and highway,,,it runs great...would appreciate any help....thanks guys
PIEMAN
As in my thread above I had the EXACT problem (except Hard Chrome pipes) driving me crazy. I am positive it is your AIS system.

I used this PDF by John A. Klopfenstein http://www.sloneservices.com/SilverBack/Other-Stuff/AIS Removal.pdf to remove mine and it worked PERFECTLY.
This is EASY to do. I got all the parts and tools, took about an hour.

At the bottom of the PDF he shows a "lazy" way to bypass the AIS. I did this first to test it and no backfire so I completed the removal.

Please read it completely as it is VERY good AND you can put everything back later if you save the parts! Good luck.

SS
 

·
Registered
Joined
·
4 Posts
glad i joined this site,,,immediate help,,,thanks for your help and i'm going to give it a try,,,,thanks a bunch,,,keith
 

·
Registered
Joined
·
1,530 Posts
Had the same problem with my 05 1100 Custom. AIS was the key. Its a fine line to walk to get rid of completely. Some unburned fuel is washed overboard on purpose as a coolant in aircooled engines. Just a warning that when you go adjusting your fuel system slower is better. You can get all the info you need here. http://www.sloneservices.com/SilverBack/VStar1100-FAQ.htm
 

·
Registered
Joined
·
4 Posts
hey guys,,,i did remove the ais system and no more back fires or popping out the exhaust,,,,very very happy. i did order the parts from maxair,,,,not here yet...i did do it the other way for now,,remove the system and leave the elbows in and plug and cap them, this will allow me to put the ais system back on if needed....will put the maxair plugs in later.....want to make sure i'm 100% happy and seem to be on my little test ride...thanks again guys for the immediate help,,,,keith
 

·
Registered
Joined
·
166 Posts
Just redid mine on my 650... again, had it disabled, had the popping again, put it back to enabled and no problem...well low and behold it started again this week... so I pulled it off again this time completely removed it all and plugged the ports, while I was removing stuff I also removed the exhaust and replaced the exhaust gaskets. Now it purrs like a lion, man oh man, I love the sound of them unbaffled 2.5 inch pipes and the Hypercharger!
I have to say I think some will get some popping due to either bad exhaust gaskets or minimum vacuum leaks as well as improper jetting...you should check all the torque specs as well for the exhaust, them copper "crush" gaskets can be a problem for exhaust leaks if not properly seated or if you try to resue them instead of replacing them like you are supposed to.
 

·
Registered
Joined
·
26 Posts
If the AIS is working properly, it shouldn't matter what exhaust you have on the bike. That is the whole purpose of the reed valve system. To shut off the airflow on deceleration. I would look to the common problem of the tubes rusting out. Or the exhaust gasket problem. That is why I am considering the oil filter relocation system for mine, so I don't have to mess with the front exhaust gasket when I change it. Then there is always the common sense answer that the aftermaerket pipes are junk, and why did one waste their money on the horrible sounding things in the first place? I did the cheap mod on my stock pipes, and I love the sound. And that staggered exhaust looks great!
Mike
 

·
Registered
Joined
·
166 Posts
I agree; that Jardine oil filter relocation is nice.......very nice,...my next mod for sure.....
anything to not have to keep giving the dealer $6.00 each time for a new exhaust gasket.
 

·
Registered
Joined
·
15 Posts
What's up everyone picked up a star 1100 hadn't run in five years went through the carbs took it out today for the first time pops and sputters at low speeds runs great at higher rpm's I sprayed some ether around the breather box and carbs at idol it didn't change the idol. So no vacuum leak I removed the ais system and plugged the ports like I said it's been sitting for years don't want to go crazy and rip it apart right away. Want to wait till I put 40 or 50 miles on it. What Is your experience with this bike I've been a Honda guy for years, so I'll defer to your opinions. Thanks
 
1 - 20 of 24 Posts
Top