Pulsing at speed.
07-07-2013, 07:04 AM
#1
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Pulsing at speed.
when crusing down the road at about 4K RPM I notice the bike has a pulse to it.. kind of revs up and down a very minor bit when held steady. Also at times it feels like the motor is sluggish, when you TTW it takes off with out hesitation.
I have read here over a dozen times that K&N air filters are bad, yes its a k&N. uptill now no issus.. but now I'm wondering..
it was very hot humid weather, might that be enough to do it?
On another note, some spoke of lifting the front end in second (16f 43R gearing).. it can't do that, normal?
I have read here over a dozen times that K&N air filters are bad, yes its a k&N. uptill now no issus.. but now I'm wondering..
it was very hot humid weather, might that be enough to do it?
On another note, some spoke of lifting the front end in second (16f 43R gearing).. it can't do that, normal?
07-08-2013, 05:43 PM
#5
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You may have a little dip at 4thou because of the K&N.
When hot and humid this can make things run a little richer which also ties in with your symptoms as an overly rich condition can make an engine feel a bit flat and not so crisp, it can also make the idle a bit rough or lumpy.
When was the last time the filter was cleaned and re-oiled because if this is blocked it will also richen things up as there is less air flow. If that is all clean and good then maybe you could do with tweaking the fuel mixture screws a 1/4 turn in to lean things off at that end of the rev range. Setting the TPS to 500 also helps with low speed steady state cruise.
(:-})
When hot and humid this can make things run a little richer which also ties in with your symptoms as an overly rich condition can make an engine feel a bit flat and not so crisp, it can also make the idle a bit rough or lumpy.
When was the last time the filter was cleaned and re-oiled because if this is blocked it will also richen things up as there is less air flow. If that is all clean and good then maybe you could do with tweaking the fuel mixture screws a 1/4 turn in to lean things off at that end of the rev range. Setting the TPS to 500 also helps with low speed steady state cruise.
(:-})
07-08-2013, 09:54 PM
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Just a thought,mine was pulsing the other day. I could feel it in the seat of my pants and hear the pulsing sound !My storm has 45000KMs on the stock chain and sprockets,sprockets still looked good but the chain was Fugged!!New drivetrain and no more pulse!
07-09-2013, 05:40 PM
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Well I think I found it and it was really stupid! I forget to reconnect the TPS last time I was working on it.. I took the carbs apart anyways to see what I could see.. ya one of the previous owners has done some serius tunning on this thing.. the K&N and the two brothers pipes were followed with block off plates a 188,183 main. that I assume came in a carb kit as the mains are marked "factory" so I'm guessing this was a "factory pro" carb kit that came with needles, not sure how he got to 188, 183 seems like a big difference but I'm sure he must have been testing it some how, dyno?.. I'm not going to play with it.. I'll put it back together sync the carbs and ride! it's got 78,000km on it right now so I'm guessing the setup works. still can't take a 954 though 
I get the jump on him everytime leave him a bike length or two behind then he flies by.. ah well.. fun little bike just the same.
I get the jump on him everytime leave him a bike length or two behind then he flies by.. ah well.. fun little bike just the same.
07-09-2013, 05:53 PM
#9
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I forget to reconnect the TPS last time I was working on it.
Yeh that is a factory pro kit and those jet sizes are about right so you good to go by the sounds of it. Don't forget FP use the same jets as Keihin and the same scaling so they are not much bigger than standard and you have a K&N.
Out of curiosity did you note what size pilot jets where in there. Did the they use the 50s by any chance? And have you got a Two Brothers full system or just end cans?
(:-})
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