sputters above 4500 rpms.

[jimgreenguy1]

Whether in 1+2+3+4 or 5th gear the bike quits giving power above about 4500 rpms, and sounds like a cylinder isn't firing. or maybe a messed up spark order.
I've read the other threads about this similar problem, but my 79xs11 special does get good spark when at idle. It starts just fine and revs normally, although i dont rev it above 3500 rpm at stand still. This problem happened litterally overnight, and no, it didn't rain. The left side cover flew off during a ride and i wasnt able to get a new one for awhile. There is some corrosion and rust inside where the pickup coil is. The bike has been rejetted, with k&n air filters and a 4 into 1 exhaust. I was told that was the cause of this, but it's been running fine for at least 4 years that i know of. I put new spark plug caps on and the ignition coils and wires look to be aftermarket.

[Phill the strat]

Re: sputters above 4500 rpms.

Originally posted by jimgreenguy1
Whether in 1+2+3+4 or 5th gear the bike quits giving power above about 4500 rpms, and sounds like a cylinder isn't firing. or maybe a messed up spark order.
I've read the other threads about this similar problem, but my 79xs11 special does get good spark when at idle. It starts just fine and revs normally, although i dont rev it above 3500 rpm at stand still. This problem happened litterally overnight, and no, it didn't rain. The left side cover flew off during a ride and i wasnt able to get a new one for awhile. There is some corrosion and rust inside where the pickup coil is. The bike has been rejetted, with k&n air filters and a 4 into 1 exhaust. I was told that was the cause of this, but it's been running fine for at least 4 years that i know of. I put new spark plug caps on and the ignition coils and wires look to be aftermarket.

Hi Jim
well that was gonna be the first point I was gonna suggest to look at..air filters and main jets... BUT you seem convinced it aint that....fuel starvation due to crap inside yer tank, blocked fuel line, pinched fuel line even.... you will need to remove the carbs and thoroughly pull em apart to clean an inspect. then when you "think" you have done this as best you can you'll then need to give them to amother XS'ive who has done this before and he'll then do it properly,...and so it goes on.....eventually you will become one of the learned XS'ives that get given a set of carbs to clean.... it all takes time an patience, and a lotta carb cleaner .......with an ultra sonic bath.

Phill

[Dennyz]

sounds like those pesky pickup coil wires to me.

[jimgreenguy1]

stupid carbs

When I bought the bike 2 years ago, it had the number one carb dumping gas and after tearing into it i found the float needle bolt loose causing the floats to stick down. I didnt have fun taking them off and cleaning all 4 carbs. I'm good with electronics and wanted to exhaust that possibility before diving into the carbs again.

[jimgreenguy1]

busted wires

wow. Okay, I just went to look at the pickup coil wires, they were all taped up and everything, i pulled off all the tape and found the biggest mess ever. I have oil and fuel leaking down to were the wires run and they are barely connected to each other. There are 3 types of wire spliced into just one line! and there is a section of milspec aircraft wire too, but that splice is a twist and tape job. I'm going to rewire all the mess and let you know if it's fixed.

[jimgreenguy1]

Odd

You know, this bike and I have a love/hate relationship. Sometimes it loves me, sometimes it hates all things sacred. The problem was not fixed after repairing the wires, however a short ride 3 hours later was fine. I adjusted the cam chain, installed new spark plugs and topped off the oil. I think she likes me again, the 91 octane gas might have something to do with it. But I think there was a kink that was worked out during my fiddling around or possibly some gunk that worked through the system.

[Mike Hart]

Jim, I clicked to get the url of your pic, and pasted it in a browser window, and saw your great looking bike. Is that a SuperTrapp 4 into 1? Nice color blue, is that a Ford color?

Not sure why it wouldn't show in your post, perhaps geocities doesn't allow outside direct links that avoid their ads? I bet that's it

[sixtysix]

Yep, no links from geocities sites! I have tried

[Dennyz]

Mike Wrote:

"Is that a SuperTrapp 4 into 1?"

Nope, it's a Kerker. At least back then. Now Super Trapp and Kerker are together.

I like the blue! (did what Mike did to view it).

[kenkrieger]

I had this problem after working on my carbs,while vacationing in New York,,,,,came back home and riding conservatively,,,,,,,as I had no place to tear it apart, in NY. I found one of the main jet bottoms rolling around in the bottom of the carb,,,,heard it as soon as I got the carbs free,,,,,,,,,I didn't tighten it up,,,,put it back in and Jeds a millionaire,,,,,,,back on the road in an hour or so.

[TopCatGr58]

Missing Picture??

Hey Mike and Gary,
I, too, did the get properties process to find the URL link address for his picture, then pasted it into the browser, went there to look, and then when I did a back click on the browser, the picture was displayed in the FORUM in his message!?!?

I then went to another thread, then came back to this thread, and the picture is still there. I wonder how this is working if Geocities doesn't allow direct links? I wonder if he didn't use the correct script in his message, putting in a Web Page link/command instead of an IMG link/command....so lets see, I'm going to put in the IMG command and try to put his link in and see if it will post/display!



Okay, just did a preview and the picture is showing in the message window!?!? YET....after submitting it, the picture disappeared again!?!? Strange

Yes, nice rich blue color, pipes, Indy filters, Plug wires, etc!!

[Dragonrider]

Once you loaded the image, it is cached on your machine, and the reference works, until your cache is cleared or overwritten.

[jimgreenguy1]

howdy

The picture works fine for me, but html can be odd at times. The pipes are Kerker, K&N filters and I have since replaced the plug caps with ngk's and that shelving unit in the rear has found a new home on the garage floor. Unfortunately the great looking blue was a lacquer based spray from a rattle can, it was eaten at first gas spill. I needed something quickly last spring and repainted with rustoleum bright yellow. Nothing gets through that paint. I was also in an accident this summer and now I need to bondo and repaint. In case anyone was wondering, the bike can be launched off a curb at 30mph, land from 10 feet up on it's side and run fine with a new foot peg, mirror and straightened handlebars. I really don't like the way people drive in South Dakota....

[kenkrieger]

Sputters

I just finished putting my carbs and airbox back on the bike. Cleaned em up after half a year riding,,,when trying to fire her up,,,no go,,,just massive back fires,,,,,so went in to check the ignition system and no spark to 1 and 4, good spark to 2 and 3,. Dam, off with the tank, to check all my connections,,all ok, went into the site and got the troubleshooting procedure on the tech tips for the missing 1 and 4 problem,,,,,went to the pickup coil connector on the Black box and the top two had on open, bottom two 740 ohms, so here we go,,,already fixed the pickup coils so started checking the harness,,,,pulled the airbox,and as it fell my meter change up to 740 ohms ont the top two, I left it plugged in as I went to see if what happened would happen. Pulled the carbs and airbox, to find the orange wire in the six pin connector hanging out the back, the tine that holds it was flattened out so it was just sliding in and out,,,bent it back out and reassembled all to find she cranked right up,,,,,,,that dam airbox and its tight fit caused this no doubt,,, lol, couldn't have been my rough handling when putting the carbs back in. You know how far back you gotta get that airbox to manuver those carbs in there,,,,,,airbox is the next amputation. thanks to the tech tips found this problem quick.
Had I had just a bit more contact there no doubt I would have had the sputters when the vibrations got going at speed. Its a good sign all my connectors will be replaced this winter as well.