bog at 3k

[banditom]

Hi Guys,
I have the rebuilt carbs back on the GLZ 82,1100,with 29k miles on it. The bike started up like it should and idled nicely. I have the idle mix screws set three turns out.

I discovered that it bogs dead at about three thousand rpm, although I dont have a tach working to confirm the actual engine speed. I dont have any air filters on, and it has straight thru shorty mufflers. It runs great up to about that three thousand mark. I rebuilt the carbs with a new, absolutely stock set of jets. I havnt ridden it at high rpm yet, but on the stand it seems to rev up ok, with no load.

I have pods, a stock airbox as well as more restrictive mufflers available to put on if needed. I do like the sound like it is, but thought I would want quieter, ergo the harley sporty muffs not yet put on. I expect youz all to say, put the airbox on, but I would like to use the pods if possible.

The floats are set to stock, by the clymer manual, cant remember what that is. That is with the bowl gasket off and at the base surface, not the little rise on that gasket surface.

Should I just break down and put bigger mains in, should I reset the needle if thats possible, reset the fuel level in the bowls such that its higher, if so how much higher. Maybe I should restrict airflow into the carbs, to see if that will improve things?? Maybe I should try to plug off the exhaust pipes such that there is a little more backpressure ?? All pipes get hot equally of course. Sorry to be so needy about this thing, but youz all are sure a great help.

[BassCliff]

Hi,

Yes, it sounds like you are running lean because of the lack of any kind of airbox or air filters and modified exhaust. Are you going to install pod filters? Are you going to use the good ones or the cheap ones? Are you going to use velocity stacks? These bikes barely run, if at all, without the airbox when using stock jetting. Just about any modification to the intake or exhaust of your engine will require re-jetting. As a general rule, when using the good K&N pod filters and a Vance and Hines 4-in-1 exhaust system you will increase the main jet by three or four sizes, increase the pilot jet by one size, and possibly shim the needles to help the midrange. Then perform plug chops to dial it in.

Your jetting will depend on what you use for air filters and exhaust. You just have to jet for your configuration. I have collected some tips HERE and HERE. These are general guidelines. Perhaps Mr. chef1366, Mr. KEITH KRAUSE, or other guru will help you with the fine points. Keep us informed.

Thank you for your indulgence,

BassCliff

[banditom]

more data

Hi Cliff and all,

Ok, got the bike running, totally stock jetting, this bike has not been run in three years at all so I am thinking that the rings may be a little sticky.

In any case, the bog that I had yesterday, is today just replaced by relatively slow acceleration. I am comparing this to my XS yam 11 and it accelerates slow. I have put the pods on, I think they are emgo brand but there are no markings, I got them with the bike. I also stuffed copper wool in those open pipes, and that even seemed to help, but I cant keep it in anyways once off idle, smile.

I am going to put an original airbox on, since I got one of those too with the bike and put the more restrictive sporty 18 inch muffs on to replace those earsplitters, this ought to bring it back to a semblence of stock, and maybe I will pick up some acceleration. I pulled the plugs, and was amazed, they are tan to gray, they look great, not white like I figured, but I do have the mixture screws out three turns and a lot of that ride was a quarter throttle or less. Also, I checked the compression after a first ten mile test ride, WOT, numbers one three and four are about 120 all of them, but number two is at 100. When I put atf in the cyls, number two climbed to 130 but the others stayed about the same or maybe five or psi higher.

I am going to leave this bike set,for a week or so, let the atf do whatever its magic is with the rings, put the official air box on and do the hardley mufffs, who knows, maybe this will be the charm.

[BassCliff]

Hi,

Yes, it is generally "best practice" to get the bike running well in its stock configuration first. Then you have a baseline for modifications, changing one thing at a time in order to ease troubleshooting. If everything is running great, you change one thing and it runs like crap, then you pretty much know where the problem might be. If you change a bunch of things at the same time it makes troubleshooting much harder.

Reading your plugs will give you insight into the last throttle setting at which they were run. In order to test all carb circuits you'll need to perform "plug chops". Run the bike at a certain throttle opening (1/4, 1/2, 3/4, or wide open) for a minute then hit the kill switch, pull in the clutch, park on the side of the road, and pull the plugs to see how they reed. Do this for each throttle opening. For a more complete explanation, CLICK HERE.

Forgive me if I state the obvious.

Thank you for your indulgence,

BassCliff