Victory Motorcycle Forum banner

1 - 16 of 16 Posts

·
Registered
Joined
·
586 Posts
Discussion Starter #1
My new used 2008 Vision has the Stage 1 upgrade. It backfires occasionally. Is this due to a rich gas mixture or a lean gas mixture? Should I take it in to reflash? I run premium 91 octane.
 

·
Registered
Joined
·
12,202 Posts
Are you talking about backfiring (which is thru the carb) or exhaust popping (thru the pipes)? If its the latter, you may be too rich. Or you "chop" the throttle between shifts. Try being a lot easier with the throttle and make less movements when shifting.
 

·
Premium Member
Joined
·
4,875 Posts
Let me guess... 1750 rpm on deceleration?

The fuel injectors are off on deceleration... they come back on at around 1750 rpm... BANG!

In your case you have no way to tune it out. The first thing to do is unplug the O2 sensors in the exhaust pipes. Just follow the wire up to the connectors and unplug them. There will be no FI light or issue.

You can also try this:
http://www.lloydz.com/store/item_view.asp?estore_itemid=1000078

Or this will definitely be worth doing:
http://www.lloydz.com/store/item_view.asp?estore_itemid=1000125
http://www.lloydz.com/store/item_view.asp?estore_itemid=1000131


Other causes are:
Exhaust leak at the header connections (failure to use new gaskets if the pipes were ever loose).
Intake vacuum leaks
Bikes as old as yours... the cap-offs on the throttle body may be rotted, or you may need to replace the rubber throttle body adaptor (rubber intake manifold). Rubber parts don't last forever.
 

·
Registered
Joined
·
12,202 Posts
The fuel injectors are off on deceleration... they come back on at around 1750 rpm... BANG!
Good reason to keep the revs above 2,000.thumb up
 

·
Registered
Joined
·
586 Posts
Discussion Starter #5
Are you talking about backfiring (which is thru the carb) or exhaust popping (thru the pipes)? If its the latter, you may be too rich. Or you "chop" the throttle between shifts. Try being a lot easier with the throttle and make less movements when shifting.
I'm hearing it through the pipes, so I figure it is the pipes. Rich running may make sense, cuz if you idle, I think it's loading up with too much fuel.
 

·
Registered
Joined
·
12,202 Posts
I'm hearing it through the pipes, so I figure it is the pipes. Rich running may make sense, cuz if you idle, I think it's loading up with too much fuel.
Disconnecting the O2 sensors and installing the Lloydz adjustable idle air valve will help reduce exhaust popping. I had some explosive popping and the above, along with the Lloydz adjustable timing wheel, has all but eliminated it.
 

·
Moderator
Joined
·
13,002 Posts
when shifting "don't" close the throttle all the way to the stop.
Other wards try doing a mild speed shift. Closing the throttle all the way cause it. We have a poor vacuum system that doesn't respond fast enough
 

·
Registered
Joined
·
586 Posts
Discussion Starter #8
when shifting "don't" close the throttle all the way to the stop.
Other wards try doing a mild speed shift. Closing the throttle all the way cause it. We have a poor vacuum system that doesn't respond fast enough
Will give that a try. It's not continuous or every ride.
 

·
Premium Member
Joined
·
9,684 Posts
This is why I am contemplating keeping my exhaust stock . I realize its ultra quiet but I can not stand the popping .
 

·
Registered
Joined
·
586 Posts
Discussion Starter #10
This is why I am contemplating keeping my exhaust stock . I realize its ultra quiet but I can not stand the popping .
I left my Kingpin stock and it was quiet and never had a backfire. Not a bad idea. I had thought about undoing the Stage 1 if anyone had the stock pipes. Will try a few of the other suggestions. Didn't have a single backfire this morning. I ran a little SeaFoam through and that probably wasn't helping the situation.
 

·
Premium Member
Joined
·
9,684 Posts
I have the timing wheel from Lloyds and gasket that HC posted , and the 1/4 turn throttle ring I may install soon . My Hammer sounded like a beast , and I loved it , but would always let off a gunshot at the worst possible time , making it sound like a crap can . I loathe this . I plan on having this bike for a very long time , and can make a plan for this slowly and methodically . If I do it , it must be done right the first time . Its upsetting that even if you shell out 1000.00 for the tri ovals or such from MA VIC , the guys say they still get popping ....
 

·
Premium Member
Joined
·
9,684 Posts
Didn't have a single backfire this morning.
I don't want to have to alter my riding style anymore in hopes my bike don't let off a big "BOOM ! " because I didn't speed shift it . It hasn't made a peep in the 1200 mi it has on it already . I like this .
 

·
Premium Member
Joined
·
4,875 Posts
I have the timing wheel from Lloyds and gasket that HC posted , and the 1/4 turn throttle ring I may install soon . My Hammer sounded like a beast , and I loved it , but would always let off a gunshot at the worst possible time , making it sound like a crap can . I loathe this . I plan on having this bike for a very long time , and can make a plan for this slowly and methodically . If I do it , it must be done right the first time . Its upsetting that even if you shell out 1000.00 for the tri ovals or such from MA VIC , the guys say they still get popping ....
With a Power Commander and adjustable IAV you can get rid of all of it... if you know how.
 

·
Registered
Joined
·
1,638 Posts
I've recently had to cold start my bike just to move it from garage to another area and then kill it. Once I later hit the starter... POW!

That one loud pop shakes me but I understand it is unburned gas in exhaust. This is the only time it happens. I'm sure letting it warm up first then shutting down would fix it but I ain't got no patience. :eek:

I'm going to wait until there are a bunch of 'exercisers' in front of my house next time and see if they hit the deck when I start it. :D
 

·
Premium Member
Joined
·
13,158 Posts
This is why I am contemplating keeping my exhaust stock . I realize its ultra quiet but I can not stand the popping .
Nah! You are still young bro. Step out and give it a go!

I understand the bike is still brand new and you are concerned about the warranty and see those dang payments every month but you don't need to worry about all that. They can only void the drive train warranty if they can prove you did something to cause an issue with it.

These motors are practically bullet proof. The weak area is the clutch and then only if it isn't adjusted right or people don't know how to let the lever all the way out. :D Seriously. Some people feather their clutch constantly just like some people ride their brakes. It's usually an unconscious habit but there nonetheless.
 
1 - 16 of 16 Posts
Top