1980 1100ET Carb Issues

[Anonymous]

Gentalmen,
I am finally at the end of the complete rebuild of my 1980 1100ET. At this time I seam to have a little problem with my carbs. I have the origanl air box with a Dyno-Jet Stage 1 jet kit a Vance & Hines Megaphone Header and the carbs were totally rebuilt by a professioal. The bike starts with no problem, idles fine after warm up and runs great. My problems start when I get around 5000 rpms where it srarts to spuder. It I stay on it past 5500 to 6000 most of the time it clears up but not allways. At this time that is the least of my two problems. The other I belive is related to the first. While traveling and a constant rate of speed normally around 4500 and up the bike will start to spuder and will lose power all together. The only way to correct it while rideing is to reduce speed and down shift which seams to correct it for the moment. As long as I do not resume the hard running the bike runs fine.
At this time I ride it all over but will normally try to stay off of open highway's for that problem. Any help would be great. I am getting ready to send a photo of the BEAST as I call it so I can show off all of my hard work.

Thanks for the GS Resources and all of your help!!!!!!
Greg

[daveo]

sounds like not enough fuel flow, I would remove and disassemble the petcock, check the diaphragm controlled valve for full travel, and the screen inside tank for crud build up

[Jethro]

I made the mistake of diagnosing a simaler problem of my own as a carb problem. It turned out to be an ignition problem. My bike idled fine and went wide open fine, but the mid range was a mess. It was the advancer and the little springs holding the arms to the crankshaft. These were bad and screwed up the timing at strange RPM's. Carbs really only have two functions- idle (or closed) and open. Usually, if the carbs are to blame, they won't run at any point that well. I just read your post again and I gotta say, this is exactly the same thing that was happening with my bike. Maybe it is the carbs (floats maybe?) but don't spend 40 hours on them like I did only to discover it was the timing.

[Anonymous]

Thanks for the replys. As for the petcock issue I rebuilt it this year and it was gone over by the Pro that rebuilt the carbs. I belive that Jethro may have hit the nail on the head. I was going over some past post about rejetting and it is quite common to have spuddering around 5000 rpms. As for the problem with the lose in power in long rides I was thinging that it may be a problem with the ignition coils. Jethero if you have the time can you give me a little more info. on how you figured the problem and what it took to correct. If I can offer any more info just let me know what you need.

Greg

[first timer]

sounds like not enough air flow into the carbs. Easy test, take the filter out of the air box and try running it see if your problem gets better or worse. a stage 1 kit usally lets you run stock air box but maybe your filter is to dirty or to oiled up, or maybe the stage 3 jets got installed by mistake. i may be totally off but it's a easy test to do. i learned that the hard way and wasted 12 hours of carb tinkering to come and find out the filters i had weren't letting enough air in. tell us what the plugs look like too please.

ryan

[Anonymous]

Thanks Ryan,
I am posting from work so can't give you the answers at this time but when I get home I will try your Idea and let you know the results tommorrow.

Greg

[Anonymous]

Thanks for the advice. I took the airbox filter out and it cleared up my problem with spuddering over 5000 rpm's. Will a K&N high flow filter help my problem or give me more of the same issues? I have not had time to see if this fix will help me with the problem of power loss during long high speed rides. I guess that will come this weekend.

Thanks again,
Greg