I want to know how hard would it be for me to re-jet my own bike. I did my own exhaust and I had a little trouble with that. Also my bike is backfiring a little bit with the new exhaust. Is there any way to stop that without re-jetting? Could the cold weather be part of the backfiring problem?
Re-Jetting?
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Changing the exhaust will generally cause a popping or backfiring because you have changed the amount of air flowing though the cylinders without changing the amount of gas. A re-jet may be in order, or you may be able to remove the brass caps from the mixture screws and adjust out the problem.
Need more info! What year/ model bike do you have? Did you put on a slip-on system that only replaced the mufflers or a complete system from the cylinder heads back? Does the new system have baffles, or is it open drag pipes?
Need more info! What year/ model bike do you have? Did you put on a slip-on system that only replaced the mufflers or a complete system from the cylinder heads back? Does the new system have baffles, or is it open drag pipes?
I love the new sound. I'm relatively good with mechanical things would it be easy for me to adjust the mixture screws. If so Where should I start 2 and a 1/2 turns?This document http://www.therusks.com/Shared Documents/How To Files/Rejet Carb.pdf applies to the Volusia 800, you have a different carb setup but it shows how to do it on a single carb setup, including drilling out the cap on the mixture screw.
You're backfiring is caused by the pair valve. You can disable it pretty easily. The pair valve is behind the chrome cover on the left side of your jugs. There are three large hoses connected to the back of it. one of the hoses goes to the airbox, the other tow go to one of the two jugs each. It's pretty apparent which hose goes where so it's almost impossible to get confused. All you need to do it remove the hose that connects to the airbox, and plug the other two hoses.
This will not affect your bike or performance at all, other than the backfiring. The pair valve is basically there for emitions purposes only.
To plug the two hoses that lead to the jugs, all you need to do is 2 golf tees. shove one into each of them, head side first, and cut off the excess tip. You'll also need to plug the airbox where you removed the third hose. You can use duct tape there; it's at the back of the airbox so it's not visible from the front.
At this point you can either reinstall the pairvalve and shove the two hoses that you plugged back into it, or you can take the pair valve completely off to get the naked juggs look.
If you decide on the naked jugs look, just wedge the two hoses back between the jugs so that hey are out of site. As for the pair valve, it is connected to the pet**** by an "F" connector that connects three hoses. The only hose you need is the one leading back to the carb. Again it is pretty obvious which hose goes where. Remove all hoses from the "F" Connector and connect the carb hose directly to the pet**** and you're done!!!!! no more back firing!
As for the rejet, it's a pretty easy mod, but I suggest you have someone there who has done it before, just in case. There are a few odd tips and challenges that are involved with the Volusia carb, so if you do decide to do it yourself, just let me know and I'll give you a step by step. Good luck!!!!!
You can email me at [email protected]
AWW CRAP!!!! AFTER WRITING THIS I FINALLY REALIZE THAT YOU DON"T HAVE A VOLUSIA AFTER ALL!!!!! NEVERMIND!!!!!!! LOL
This will not affect your bike or performance at all, other than the backfiring. The pair valve is basically there for emitions purposes only.
To plug the two hoses that lead to the jugs, all you need to do is 2 golf tees. shove one into each of them, head side first, and cut off the excess tip. You'll also need to plug the airbox where you removed the third hose. You can use duct tape there; it's at the back of the airbox so it's not visible from the front.
At this point you can either reinstall the pairvalve and shove the two hoses that you plugged back into it, or you can take the pair valve completely off to get the naked juggs look.
If you decide on the naked jugs look, just wedge the two hoses back between the jugs so that hey are out of site. As for the pair valve, it is connected to the pet**** by an "F" connector that connects three hoses. The only hose you need is the one leading back to the carb. Again it is pretty obvious which hose goes where. Remove all hoses from the "F" Connector and connect the carb hose directly to the pet**** and you're done!!!!! no more back firing!
As for the rejet, it's a pretty easy mod, but I suggest you have someone there who has done it before, just in case. There are a few odd tips and challenges that are involved with the Volusia carb, so if you do decide to do it yourself, just let me know and I'll give you a step by step. Good luck!!!!!
You can email me at [email protected]
AWW CRAP!!!! AFTER WRITING THIS I FINALLY REALIZE THAT YOU DON"T HAVE A VOLUSIA AFTER ALL!!!!! NEVERMIND!!!!!!! LOL
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9,731 Posts
Ripped from Migcruisers.com
The PAIR valve on the Marauder and Intruder LC is used to burn off hydrocarbon emissions from incomplete combustion that occurs during deceleration in gear. It works like this:
When you open the throttle on your bike, manifold vacuum drops off since air is entering through the carbs. This air mixes with fuel that is burned in the combustion chambers, more or less completely. When you let off the throttle, particularly in gear, the throttle plate closes, restricting airflow to the combustion chambers, and the manifold vacuum goes way up. This is particularly the case when coasting in gear since the engine is being pushed by the rear wheel at speeds above idle. Since the throttle plates are closed, a high vacuum is developed. This vacuum pulls fuel from the carbs into the engine, but the mixture is too rich for it to burn. It's dumped unburned into the exhaust system.
This is where the PAIR valve comes in. The valve is controlled by manifold vacuum. When vacuum increases (pressure decreases), the valve is pulled open. On the Marauder, fresh air is drawn in through the PAIR's air filter and fed into the exhaust port of the cylinder heads. On the LC, the source of fresh air is from the rear cylinder airbox. That air provides the right mixture to spontaneously ignite the hot unburned fuel exiting from the exhaust valve.
If you have stock pipes, you won't notice this effect. However, change to less restrictive aftermarket exhaust, and the combustion takes place futher down the pipe, resulting in sounds that people describe as backfiring, burbling, popping, etc., during deceleration. The sound you're hearing is the sound of the exhaust gasses burning off. Some folks kinda like the sound, others can't take it.
What can be done about it? You can disable or remove the PAIR valve from your bike. This will in no way affect performance, even a little. All it will do is remove the backfire, and of course, increase hydrocarbon emissions. The valve can be disabled by disconnecting and PLUGGING the vacuum line that controls it, or by blocking its fresh air intake. The valve can also be completely removed from the engine, revealing those beautiful V-twin jugs hiding underneath.
In order to remove the valve, though, the vacuum lines must be properly plugged to prevent air leakage into the manifold, the fresh air inlets into the cylinder heads must be blocked, and in the case of the LC, the fresh air port on the rear airbox must be plugged. You can probably fabricate everything you need to do this, but there's a better way...
Check out Moccasin Mike's website for information on his PAIR valve removal kit. It's a great deal at only $15 and contains everything you need. Detailed instructions for the Marauder and the LC are also included. Mike's website is:
http://www.moccsplace.com/images/pair/pair.htm
The PAIR valve on the Marauder and Intruder LC is used to burn off hydrocarbon emissions from incomplete combustion that occurs during deceleration in gear. It works like this:
When you open the throttle on your bike, manifold vacuum drops off since air is entering through the carbs. This air mixes with fuel that is burned in the combustion chambers, more or less completely. When you let off the throttle, particularly in gear, the throttle plate closes, restricting airflow to the combustion chambers, and the manifold vacuum goes way up. This is particularly the case when coasting in gear since the engine is being pushed by the rear wheel at speeds above idle. Since the throttle plates are closed, a high vacuum is developed. This vacuum pulls fuel from the carbs into the engine, but the mixture is too rich for it to burn. It's dumped unburned into the exhaust system.
This is where the PAIR valve comes in. The valve is controlled by manifold vacuum. When vacuum increases (pressure decreases), the valve is pulled open. On the Marauder, fresh air is drawn in through the PAIR's air filter and fed into the exhaust port of the cylinder heads. On the LC, the source of fresh air is from the rear cylinder airbox. That air provides the right mixture to spontaneously ignite the hot unburned fuel exiting from the exhaust valve.
If you have stock pipes, you won't notice this effect. However, change to less restrictive aftermarket exhaust, and the combustion takes place futher down the pipe, resulting in sounds that people describe as backfiring, burbling, popping, etc., during deceleration. The sound you're hearing is the sound of the exhaust gasses burning off. Some folks kinda like the sound, others can't take it.
What can be done about it? You can disable or remove the PAIR valve from your bike. This will in no way affect performance, even a little. All it will do is remove the backfire, and of course, increase hydrocarbon emissions. The valve can be disabled by disconnecting and PLUGGING the vacuum line that controls it, or by blocking its fresh air intake. The valve can also be completely removed from the engine, revealing those beautiful V-twin jugs hiding underneath.
In order to remove the valve, though, the vacuum lines must be properly plugged to prevent air leakage into the manifold, the fresh air inlets into the cylinder heads must be blocked, and in the case of the LC, the fresh air port on the rear airbox must be plugged. You can probably fabricate everything you need to do this, but there's a better way...
Check out Moccasin Mike's website for information on his PAIR valve removal kit. It's a great deal at only $15 and contains everything you need. Detailed instructions for the Marauder and the LC are also included. Mike's website is:
http://www.moccsplace.com/images/pair/pair.htm
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