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I have a '99 California emmisions bike. I marbled it over the weekend and it runs great. My question is in regards to the tube coming off the right side of the tank. It seems like old dog said to pull the hose and cap the tank. If so, do I then need to plug the hose as well or just remove it? Finally, the tube coming from the left side of the tank can just run straight down under the engine as a vent (remove it from the seperator/ return pump)?

Thanks!:zzz:
 

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The Professor
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Plug right tank vent, right carb vacuum port and let left tank vent to atmosphere.:beerchug:
 

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Lance is right, but you are mixing 2 different systems. CA bikes (mine was one) have 2 completely separate systems, the air injection system that all VN750s have, and an evap emissions system. The best thing to do is to COMPLETELY remove both systems. That's what I did. Eliminated about 100' of hose and 20 pounds of junk. You will need to plug the reed valve ports on each head (I used rubber caps, but a neater way to do it is to use "coasters". You will need to plug the vacuum fitting on the rear carb, a couple of holes in the airbox, the right tank vent, and then run a line from the left tank vent down below the bike somewhere, and leave the end open. I even went so far as to remove the bracket that the evap cannister attaches to, which is difficult, because the swing arm gets in the way of removing the bolts. I unscrewed them part of the way, then cut the heads off, and unscrewed what was left of them was needle nose pliers. I was determined to get all that EPA crap off my bike. And it makes me feel so much better now that it is gone. Not only is the bike a LOT less cluttered, but the exhaust runs cooler, doesn't backfire on deceleration anymore, and the engine no longer suffers from starting/running problems if you fill the gas tank more than 3/4 full.


BTW, I live in the only county in the U.S. that emissions tests motorcycles, and mine still passes. A state law was passed almost 2 years ago eliminating the motorcycle emissions tests, but was contingent upon federal EPA approval. They have until July 31st 2010 to approve it. I'm sure hoping they do. I have 5 street bikes, and they all pass, but it is a real hassle, and very expensive. Jerry.
 

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I'm new with engine's so please bear with me! My evap system is gone, so now for the removal of the Air Injection system. So i need to remove the surge tank(Air injection System?)? Also, If I'm going to put K&N filters on, I will need to remove the air boxes as well?
 

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'85 Bobber
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Yes, remove surge tank and also remove air boxes.
 

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Thanks for the confirmation. I think I'm going to read through the site more and then attempt this ear shave i keep seeing everywhere. The damn airboxes bug the hell outa me!
 

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Look at pictures of bikes without them first. IMO, something needs to go there. I am considering removing the airbox and going with individual filters, but I either want the stock filter housings or something to replace them with to remain. It's the airbox and it's associated plumbing I don't like, not the "ears". It's kind of like the evap system and air injection I already removed. IMO, the simpler the better.


But. I just recently installed V&H Cruzers, and rejetted the carbs, and am concerned how that will affect it passing the emissions test, if we still have them when it comes due again in October. Most bikes here have aftermarket pipes, and still pass, but I still want to be sure before making any more jetting changes. Jerry.
 

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So i decided to wait on the attempt to modify my carbs with the K&N pods and just thought I should at least try to get it running first. I plugged the right gas tank vent, vacuum fitting on the rear carb (the right side correct?), and plugged the holes in the surge tank (this is the airbox correct?). I tried to start it up from there but it just would fire up. The electrical is all good and it turns over. The bike did have old gas in it when I bought it so my friend and I put some new gas to mix with the old and hoped that would help. My friend are going to try using some starter fluid and see if anything happens. If this doesn't do anything, can anyone help with some suggestions? Also, Jerry mentioned that I need to plug the Reed Valve Ports on each head, but I don't where or what these are. Someone please point me in the right direction!!! Thanks a ton!
 

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How old was the old gas? If it was more than six months or you don't know, get rid of all the gas and start with fresh. But before you do, look in the tank to see if there is any rust in it. If so, you'll need to clean the tank before proceeding. You can do a search on tank cleaning here and get several methods that work. Have you cleaned the carbs or at least soaked them with Sea Foam?
 

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I want to say it was around 5 months old. I haven't cleaned the carbs at all or soaked them. Would I need to remove them to do this? Also on a side note, we sprayed some starter fluid in the airbox and BOOM, it started right up! I rode it around the block for bit to get a feel for it. I noticed that it seems like it's lacking some power. Even with the choke on and the Idle screw turned all the way up, it just barely stays over 1rpm. I let it warm up for a good 10 min and then took it around the block and the same thing it was idling low and whenever I took the choke off it would die. Also it seems that the warmer it was, the more it wanted to die. Any idea what this could be caused by or what I can mess around with to try and get idling higher?
 

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The reed valve ports are on the heads, front on the right, rear on the left. They are where the BIG hoses go to from the air injection valve under the seat. You can get "coasters" to do a really neat clean job, I just went down to Pep Boys, in the HELP! section, and picked a couple of the rubber caps made to plug off car heater hose connections. I don't remember the size, but there are 2 sizes, and these were the smaller ones.


I would remove the tank, pour out all the gas, pour in about a gallon of fresh gas, close the cap, shake the hell out of it for a couple of minutes, then pour out that gas. Next, remove, disassemble, and clean the carbs. They are probably filthy inside. It is not an easy or fun job on a Vulcan 750, but it is the only way to get them clean. Once that is done, put everything back, pour 4 oz of Seafoam in the tank, and fill it up with gas. If the carbs are clean, and gas is getting to them, it should fire right up. Here, a 16 oz can of Seafoam costs $10, but that is enough to treat 4 tankfuls of gas on the Vulcan. By then, everything should be clean. Use a can about every 3 months. I drain the gas out of my carbs about every 3 months, remove the fuel lines from the tank, and use them to fill the carbs full of Seafoam. I let it soak for 24 hours, drain it out, hook the fuel lines back up, and fill the carbs back up with gas. I then use the rest of the can of Seafoam in the next 3 tanks of gas. That pretty well keeps the fuel system clean. Jerry.
 

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Thanks a ton Jerry, I'll definitely clean the carbs and keep maintaining them like you said. Do you think the old gas and dirty carbs has something to do with what I mentioned about the idling issue?
 
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