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Discussion Starter #1
Just bought a pretty nice 07 1100 Custom, bone stock, 5300 miles. First order of business was new exhaust (I need to hear it running). Bought a set of Cobra slip ons. Up to this point, I had no reason to believe the bike wasn't running right. I had it out for a ride and it seemed fine except for being too quiet. Got the new slip ons and installed them and was looking forward to hearing that sweet sound! (I had a Silverado 1600 before so I knew how it should sound). When I fired it up, I was sorely disappointed. It's sounds like it's running on one cylinder. First step was to check the plugs. They were not the plugs recommended for bike, they were not tight but didn't look bad. I got the right plugs and installed them. Also put some Seafoam in the gas to help any potential carb issues. Tried it again, no change. Ironically, it's seems to run ok, both pipes get hot etc. I'm stumped.
I've had a number of other bikes, done most of my own work and know for sure what this should sound like and it doesn't. Any help is greatly appreciated.
 

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getting the bike to run well and getting it to sound a specific way are two different things.

the first step is to make sure the bike is running correctly - if there is hot exhaust coming out both pipes then both cylinders are firing.

You should be able to take an 1100 out on the highway and it should peak its HP in 4th gear around 55 to 60mph,

peak HP in 5th gear should be around 75mph - the bike should be growling with glee with the throttle wide open at those speeds in those gears, and going like a bat outta hell.

If its doing that, its running right. If its bogging down check your air filter and see if its white like new paper, or grey like an old tee shirt. The stock air filters are somewhat small, and it doesnt take much to reduce their air flow and choke off your bike.

The only other thing I can think of, make sure there was no packing material stuck in one of the slip on pipes. Maybe it was packed in shipping peanuts and then packed in something else, and you got something wedged in one of them.
 

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Please elaborate. I read that it runs good, both pipes hot. How does it run on throttle? Does it accelerate good. Does it idle OK. Is the only issue the sound of new exhaust? Most of the time with slip on exhaust at idle speed it's still pretty quiet and only has a "bark" is upon acceleration.
 

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Discussion Starter #4
Ok, decided to take the bike to a reputable local shop. This is a first. I rode it to the shop and started telling them the problem I was having. Before I finished telling him, he looked at me and said, let's go hear it. We went out along with another guy (the owner) and I started the bike for them. They said yep, we've seen this a number of times before. The timing on one cylinder is out 180 degrees and both cylinders are firing at the same time causing it to sound like it's only running on one cylinder but yet both pipes are hot. Could've happen when someone else worked on the bike and they mentioned something else that I didn't understand. After reading some other posts related to this, it sounds like the timing on these is pretty complicated. They said it'll be a week plus before they get to it so when I hear back, I'll update as closely as possible as to exactly what was wrong. In the meantime, I'm relieved to hear that they're pretty certain what the problem is and I can't wait to ride my corrected motorcycle!
 

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Sounds unusual to me that both pipes are getting hot but only one cylinder is firing. Good luck and keep us informed.
 

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Our Yamahas utilizes a duel fire ignition. Both cylinders do fire at the same time but each cylinder is at a different part on stroke. From my experience when timing is off there is a lot of either exhaust or intake back firing and you did not mention this happening. Please keep us informed on fix as I'm very curious. Timing on these bikes don't get off without major outside assistance. The timing operation is a little complicated but extremely reliable. Here's a link taking about duel fire ignition, it's talking about Harley but our system is the same.
https://www.google.com/url?sa=t&source=web&rct=j&url=https://www.motor-talk.de/forum/aktion/Attachment.html?attachmentId=731058&ved=2ahUKEwiCnL-kkN7eAhWhx4MKHZ7xCM8QFjABegQIDhAE&usg=AOvVaw3gGQUfQVd6wucsrwPJNB-n
 

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Its a matter of wording, but the two cylinders on a V twin cannot both fire at the same time, because the front cylinder reaches top dead center 90+ something degrees after the rear cylinder (the 650 and 1100 engines spin the opposite direction from the front wheel).

What the mechanic is saying is: the cylinders are suppose to fire on alternate revolutions of the crankshaft. While one piston is on its compression revolution the other is on it exhaust revolution.

If someone accidentally or intentionally changed the position of the front cam shaft (timing) so the rear piston fires, then 90+ degrees forward the front piston fires, then the crank goes around and both exhaust on the same revolution... that is what the mechanic is saying. The two pistons would fire so close together it would sound like they fire at the same time. If you put your hands over the exhaust you should be able to feel it at idle speed.

Im not sure about this, but I think some Harley engines are set up this way, and that is why they vibrate like a paint can shaker.

Its possible a previous owner changed the timing on the bike intentionally to make it run this way. If thats the case you dont have to change it back, unless it bugs the hell out of you to ride it that way.

Its also possible someone changed the timing chain or tensioner, or replaced the starter clutch, and dropped the timing chain, had to align the timing again and got it off 360 degrees on the front cylinder.

Since the 1100 does have a problem with the starter clutch if you rev the engine will you are starting it... I guess both causes are equally possible.

BTW: this does not happen very often - I think this is the FIRST time this has come up with a Vstar bike.
 

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Discussion Starter #9 (Edited)
The guys at the shop said they had seen this 'a number of times before' on this particular year and also mentioned something about a recall. I can't find any info to substantiate that.They've been in business for over 50 years and their primary business is Yamaha. I realize that doesn't make them the hands down authority on Yamaha but...
I certainly have never heard of anything quite like this and will be very curious to learn what they find and how they resolve and will post here.
 

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The bike does fire both cylinders at the same time. Excerpt from old post.

"the reason they look out of sequence is because the ignition system is a waste spark system... meaning the the coils double fire. both coils fire each time the flywheel magnet passes the pick up coil. so one cylinder is firing near the top of the compression stroke and the other cylinder is firing at the exhaust stroke IE waste spark. even if you reverse the the plug wires the engine will run exactly the same, the reason there's a front coil a rear coil is for routing purposes"

https://www.starbikeforums.com/forums/49-v-star/81969-front-cylinder-not-firing.html

I'm sure your mechanics heard something we can't. On a bone stock bike with only 5300 miles it's hard to believe that it jumped timing, but stranger thinks have happened.
 

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Discussion Starter #11
OK, here's the conclusion. The shop discovered that the starter clutch had been replaced and the timing was set incorrectly when reassembled. They basically had to repeat the process, excluding replacing the starter clutch to correct the timing. NOW it sounds like it should and, of course, runs better.
Thanks to all who responded.
 

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OK, here's the conclusion. The shop discovered that the starter clutch had been replaced and the timing was set incorrectly when reassembled. They basically had to repeat the process, excluding replacing the starter clutch to correct the timing. NOW it sounds like it should and, of course, runs better.
Thanks to all who responded.
That's great it now running right. I find it interesting that the starter clutch had been replaced with only 5300 miles. Here's a link for starting an 1100 to eliminate starter clutch issues.

https://sites.google.com/site/vstar1100kb/home/new-owner-must-do-list/using-the-choke
 

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thats the damnedest thing Ive heard in a long time

good to hear you got the bike made right again.
 

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As lesblank pointed out many bikes have a 'wasted spark' ignition, that's typical for many bikes. My 2000 Sporty has that type of ignition where each cylinder's spark plug will fire twice for every combustion cycle, one spark actually ignites the air/fuel mix but the other does nothing since it occurs when there's nothing to ignite but that ignition system was updated with the next generation like my 2006 Sporty which fires once for each cylinder individually.
 
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