aperry62
Active member
Ok guys, this bike is starting to be the bain of my existance. It's a pretty long story that can be read on the NAGF site (https://www.northamericangoldwings.com/v ... orum_id=25). To make a long story short the bike seems to have not bottom end at all and stumbles and grumbles below 1200rpm. Once you through the choke on or give it throttle it goes like a raped ape from about 1400rpm through redline.
The problem was originally very intermitent like once every few months but then it degreaded to a point where it is happening constantly. It first manifested itself right when I started it up on a cool night on my way home from work (had run beautifully on the way to work). The next time was a few months later when it was hotter than blazes and it happened immediately at a stop light after getting gas. So I shut it off waited a couple of minutes and then started it back up again. Rode fine all the way back to my parents place but did it again later in the afternoon (still hot). Later that fall I was getting ready to ride it to early morning practice and it did it to me again and made me late for rehearsal so I put it in the garage until I could figure what was wrong with it. At that point it was doing this problem all the time.
So I tore the covers off and started looking to see if it was possibly a fuel problem. I was thinking that maybe it had a vacuum leak on the under side of the carbs that was resulting in an ultra-lean situation until the main jets opened and riched the mixture. I sprayed carb cleaner all around the underside of the carbs to see it that would make the problem go away and sure enough there were several hoses with cracked ends. So I took the carbs off and rebuilt them using the kit from Randakk. They were a little dirty but cleaned up really well and all the passages were nice and clean. Reisntall carbs on the bike and no luck, same thing happening.
I checked for spark on each cylinder and they were all firing nicely and the engine would stumble when I took the plug boot off, and recover when reinstalled. I replaced ALL the vac hoses on the carbs so I know that there isn't any problems with the vac system. I finally gave up and took the old girl into my buddy at the motorcycle shop. My buddy started by scoping each cylinder and he noticed that the #4 cyclinder looke like it was cracked and had a chunk missing. Several explitives later I talked to his boss and asked him if he thought it was the same thing, which he did. So I told them to stop working on it and I would grab it and bring it home. I found a guy with a spare motor through the NAGF and GWRRA forum (same guy) and made arrangements to meet up and pick up the motor.
I then tore into the bike and took off the left cyl head to see the carnage for myself. Nothing except a little discoloration (I had looked through the scope and thought there was a piece missing also) and you could still see crosshatch marks. Well there goes that idea. I thought that I would still pickup the other motor because #1:it was a good deal and #2 it had another set of carbs along with it.
So I swapped out the original motor, put the donor motor in, put on the original set of carbs, fired it up and guess what.....SAME PROBLEM. I had to leave because the string of expletives coming out of my mouth and flying around was making it hard to breathe. So I thought, I have another set of carbs, I'll throw them on and see what happens. What happened was a fuel leak like i took a bunch of gas and dumped it out. Old carbs out, repair main leak, reinstall, new fuel leak from the left side transfer tube. Revist original carbs and blow out all the fuel passages again with the air compressor (didn't have it hooked up when I rebuilt them the first time) and reinstalled. Fire it up...SAME PROBLEM. Everyone that has posted about the same problem has had a plugged pilot jet. Mine are clear and set to 2.5 turns out from a soft seat.
Anyway I better quit typing before the keyboard melts. I took a video today and posted it on youtube https://youtu.be/p3UMdnY_mog
Here are links to the previous videos that I have posted throughout this project:
https://www.youtube.com/watch?v=Ypo0EvAgET0
https://www.youtube.com/watch?v=Vo7pV5VYxEo
I have tryed to sync the carbs also but really hard to do when it won't idle. When I have the guages hooked up all cylinders seem to be right close to each other. Compression in the cylinders was about 160ish on the original engine and probably a bit lower in the donor motor (I don't really trust my guage giving me an accurate reading but they were all about the same.
I would definately welcome any and all suggestions as to the cause of the problem. If you can't tell I'm getting pretty sick of this bike and if I can't get things figured out soon I might see how well it floats when I run it into the river!
The problem was originally very intermitent like once every few months but then it degreaded to a point where it is happening constantly. It first manifested itself right when I started it up on a cool night on my way home from work (had run beautifully on the way to work). The next time was a few months later when it was hotter than blazes and it happened immediately at a stop light after getting gas. So I shut it off waited a couple of minutes and then started it back up again. Rode fine all the way back to my parents place but did it again later in the afternoon (still hot). Later that fall I was getting ready to ride it to early morning practice and it did it to me again and made me late for rehearsal so I put it in the garage until I could figure what was wrong with it. At that point it was doing this problem all the time.
So I tore the covers off and started looking to see if it was possibly a fuel problem. I was thinking that maybe it had a vacuum leak on the under side of the carbs that was resulting in an ultra-lean situation until the main jets opened and riched the mixture. I sprayed carb cleaner all around the underside of the carbs to see it that would make the problem go away and sure enough there were several hoses with cracked ends. So I took the carbs off and rebuilt them using the kit from Randakk. They were a little dirty but cleaned up really well and all the passages were nice and clean. Reisntall carbs on the bike and no luck, same thing happening.
I checked for spark on each cylinder and they were all firing nicely and the engine would stumble when I took the plug boot off, and recover when reinstalled. I replaced ALL the vac hoses on the carbs so I know that there isn't any problems with the vac system. I finally gave up and took the old girl into my buddy at the motorcycle shop. My buddy started by scoping each cylinder and he noticed that the #4 cyclinder looke like it was cracked and had a chunk missing. Several explitives later I talked to his boss and asked him if he thought it was the same thing, which he did. So I told them to stop working on it and I would grab it and bring it home. I found a guy with a spare motor through the NAGF and GWRRA forum (same guy) and made arrangements to meet up and pick up the motor.
I then tore into the bike and took off the left cyl head to see the carnage for myself. Nothing except a little discoloration (I had looked through the scope and thought there was a piece missing also) and you could still see crosshatch marks. Well there goes that idea. I thought that I would still pickup the other motor because #1:it was a good deal and #2 it had another set of carbs along with it.
So I swapped out the original motor, put the donor motor in, put on the original set of carbs, fired it up and guess what.....SAME PROBLEM. I had to leave because the string of expletives coming out of my mouth and flying around was making it hard to breathe. So I thought, I have another set of carbs, I'll throw them on and see what happens. What happened was a fuel leak like i took a bunch of gas and dumped it out. Old carbs out, repair main leak, reinstall, new fuel leak from the left side transfer tube. Revist original carbs and blow out all the fuel passages again with the air compressor (didn't have it hooked up when I rebuilt them the first time) and reinstalled. Fire it up...SAME PROBLEM. Everyone that has posted about the same problem has had a plugged pilot jet. Mine are clear and set to 2.5 turns out from a soft seat.
Anyway I better quit typing before the keyboard melts. I took a video today and posted it on youtube https://youtu.be/p3UMdnY_mog
Here are links to the previous videos that I have posted throughout this project:
https://www.youtube.com/watch?v=Ypo0EvAgET0
https://www.youtube.com/watch?v=Vo7pV5VYxEo
I have tryed to sync the carbs also but really hard to do when it won't idle. When I have the guages hooked up all cylinders seem to be right close to each other. Compression in the cylinders was about 160ish on the original engine and probably a bit lower in the donor motor (I don't really trust my guage giving me an accurate reading but they were all about the same.
I would definately welcome any and all suggestions as to the cause of the problem. If you can't tell I'm getting pretty sick of this bike and if I can't get things figured out soon I might see how well it floats when I run it into the river!
