Desmog anybody?

[chief]

That is fairly typical of Drifters. It is venting as it is supposed to but makes a little racket when there is a lot to vent.  Pop open the gas cap, close it back up and that resolves the issue until next time!.

[Tfrank59]

OK will do. Thanks.

[gdrudd13]

There is a vent built into the gas cap. On the gas cap mount there is a small rubber gasket that coincides to a metal tube on the cap. Take off the gas cap and first run a wire or pipe cleaner or something through the hole in the tank. doesn't have to go all the way through, just enough to make sure there isn't any gunk. The easiest way to clean the cap is to take it apart. It's not hard. Just don't lose any of the pieces.

[Tfrank59]

OK also good info.  None of my hoses are kinked – I've double checked it.  But to test the gas cap vent, how would I do that?  While she was singing slowly venting the other day, I opened the gas cap and the singing all of a sudden stopped.  That tells me that it was venting, just not very fast until I opened it, right?  At any rate, I filled the tank with ethanol free 92 octane, and I also put in some fuel system cleaner, and since that fill up I've run her about 75 miles and she's running quite good.  I think if there were a problem with fuel flow I would've noticed it by now.

[gdrudd13]

One thing you might try is to make sure that the vent hose isn't kinked, and also that the vent in the gas cap is working properly. Both could possible cause the issue you have.

The hose that goes to the evap cannister isn't actually a vent per se. It's for trapping fuel vapors that are collected and then one of the other hoses that was removed is for returning the now condensed fuel back to the tank. The thing the vacuum line went to is a pump that pumps it back into the tank.

[Tfrank59]

OK good info. I thought that was the deal because I saw I have actually two vent hoses going from the tank.  Interestingly the desmog procedure that I followed (got from this forum) had me cap off a third tank hose – I think that went to the evap canister.  I'm just curious because I've never had a bike that sang for me like that when she was venting

[Troll]

Well, I got her back together with the baffles and back pressure now about where they should be, although I have nothing to compare it to    Actually what I've been comparing it to is my 1500 flat six Valkyrie, so the little drifter always comes up a bit short   Still for what it is I think it's running good.  After I kill it when it's hot, I hear the tank vent singing trying to suck more air into the gas tank than it can or maybe it's pushing out I'm not sure--I guess when it's venting it's pushing air out? (like an angry wife)   Anyways does your guys tank vent make a singing noise?  Elsewise I think my desmog went OK, the bike didn't quit or anything and it seems to be running pretty good like I said...

After the bike (or any vehicle) sits on a warm day, after it's been running up to temp, the system has to deal with expansion of fuel vapor. It's called "hot soak". If it DOESN'T vent, then you have a problem. The normal 49 state system vents to the atmosphere, and also has a vacuum vent to allow air back inside the tank as fuel is consumed. If it did not do that, too, you would get a vacuum lock on the fuel tank.

[CDNRatMan]

  On a hot day when I have shut down and am rolling the bike in or out of the shed I can hear it venting, and on a hot day when I move it or stand it up it vents.

[Tfrank59]

Well, I got her back together with the baffles and back pressure now about where they should be, although I have nothing to compare it to    Actually what I've been comparing it to is my 1500 flat six Valkyrie, so the little drifter always comes up a bit short   Still for what it is I think it's running good.  After I kill it when it's hot, I hear the tank vent singing trying to suck more air into the gas tank than it can or maybe it's pushing out I'm not sure--I guess when it's venting it's pushing air out? (like an angry wife)   Anyways does your guys tank vent make a singing noise?  Elsewise I think my desmog went OK, the bike didn't quit or anything and it seems to be running pretty good like I said...

[gdrudd13]

In my quest to figure out what to remove I capped a line that should have been open, and the bike didn't run at all, so it'll be obvious.

[Tfrank59]

Right, I'm not expecting any change – at least not for the better – but if I screwed up something it'll be a change for the worse

[gdrudd13]

If it's like mine, I doubt you'll notice a difference from it other than your bike just got about 5 lbs lighter from getting rid of all that crap.

[Tfrank59]

OK, I did the desmog per your diagram and instructions.  Exhaust is off the bike being worked on, so I can't try it yet but it won't be long.  I'll let you know how it runs, thanks again.

[Tfrank59]

Excellent – thank you, I'll let you know how it goes.  Haven't been under my tank yet, but if I can't see a color band on the hoses I might be back.

[gdrudd13]

Yellow hose at carb-This should be left open to vent
Green hose at intake-This can be capped
Blue hose at right hand of tank-This needs to stay, this is the tank vent.
Red hose on left hand side of tank-This can be capped
vacuum line- This can also be capped

This is exactly what I am running on my bike right now. All the hoses should have some sort of colored band if not, there is a diagram that I'll copy. The blue line that is being discussed is the tank vent. Run it to a place on your bike that is out of the way and you'll be fine. As for the hoses that are capped, I just used the silicon hose caps. you can buy a bunch off of Amazon for cheap. Hope this answers your question.

[Tfrank59]

I really appreciate that link, which brings up the discussion of a lot of things – especially an ongoing discussion about what to vent and what to cap off when ditching the emissions crap.  I'm just afraid that without an actual diagram showing what has to happen to all the hoses (and the final result of all of your tests and revisions) that I'll screw it up and it won't even run, or maybe like with troll it'll run until the tank is half empty and then quit.  You see I'm not that smart like you guys and can figure out stuff like that after-the-fact.

[gdrudd13]

I removed all the smog stuff on my bike. Unless you have a problem with some of the components, it doesn't really do anything other than open up the tool box area on the right side of the bike. That was one of the main reasons I did it to my bike.

http://www.vulcandrifterriders.com/forum/index.php?topic=32387.msg70698#msg70698

Scroll down and you'll find the post.

[LarryInSeattle]

I am in Lynnwood.  Where are you? 

[Tfrank59]

Not much to doing it. All you need to do is keep an atmospheric tank and carb bowl vent. Plugging off the AIR intakes to the reed valves stops the pop on decel

Well right now I have quite a bit of popping on decel.  Still, my exhaust back pressure isn't quite right even with baffles now in my straight pipes, so I'm going to buy some additional exhaust tips or something to help me tune my exhaust better.  I believe I'm moving in the right direction on engine performance by increasing back pressure.  And then once I got the exhaust where I want it, and the smog stuff is correctly removed, I can deal with rejetting the carb.

[greenbarn]

The "grampsize" mod walks you through getting rid of the additional hardware,  in addition to increasing the air flow and re-jetting.  You could drop the junk and leave the air box alone, if you wanted to.

http://www.vulcandrifterriders.com/mods/grampsize.pdf

[Troll]

Not much to doing it. All you need to do is keep an atmospheric tank and carb bowl vent. Plugging off the AIR intakes to the reed valves stops the pop on decel 

[CDNRatMan]

   Sorry new to me....never heard tell of this .....

[Tfrank59]

OK, I just checked on evil-Bay for a Drifter desmog kit – nope don't see one.

[Tfrank59]

Yeah, I'm just full of questions this weekend!  So evidently I have a California bike – it has the emissions canister and everything underneath the right side cover – does anybody know how to do the Desmog because I don't need that stuff here in Washington state.  I know that some of those vacuum hoses have to be rerouted or plugged or something, and it's way above my pay grade but I would like to do it because, well just because who likes a lot of extra junk under the hood that you don't have to have.    I know that for Valkyries and some other bikes there is a Desmog kit with detailed instructions – any such thing out there for 800 Drifters to your knowledge?