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Bike got more responsive/powerful out of nowhere

Discussion in 'The Garage' started by wingstar, Sep 19, 2020.

  1. wingstar

    wingstar XS400 Member

    I was practicing on my 81 xs400 (first bike) and out of nowhere it began to idle really well, and doesnt bog down when i initially give it throttle (been trying to fix this, but im kinda inexperienced). At first i was like 'cool!' But then i looked behind me and there was a decent sized cloud of exhaust gas behind me. It didnt have that blue tinge that it would have if oil is being burned, but theres just a lot more exhaust gas coming out in general. Should this worry me at all? Because the bike is performing so much better than it was before
     
  2. amc49

    amc49 XS400 Addict

    If you have been running with a fouled plug and suddenly it began to work then you just doubled the engine size.

    I remember nextdoor neighbor who had a Kaw 750-3 and always driving it around on only 2 cylinders and bragging about how fast it was. I talked him into letting me tune it up and then with number 3 working he became so terrified of how fast it was he sold it to me. Hunh.
     
  3. wingstar

    wingstar XS400 Member

    Don't believe either of the plugs were fouled... They are basically brand new
     
  4. amc49

    amc49 XS400 Addict

    That means literally nothing. I've had so many people swear that then I prove them wrong I cannot count. That may mean nothing as well though. My point is that I have a viable explanation for it and you..........do NOT.

    Pull a plug wire and see if the way it runs is familiar.
     
  5. wingstar

    wingstar XS400 Member

    Alright ill give it a try probably tomorrow. Now that I think of it, that might have been what was happening. After I saw the puff of smoke I checked at the end of the muffler and it was wet with a lot of fuel. Probably just excess fuel caused the smoke
     
  6. amc49

    amc49 XS400 Addict

    Beware, that can be a deadly fire issue if you backfire into liquid fuel to ignite it.
     
  7. wingstar

    wingstar XS400 Member

    Im well aware of that, it has evaporated by now
     
  8. amc49

    amc49 XS400 Addict

    I'm at this moment thinking of someone who said something very similar to that seconds before he burned about half of his face off............not kidding on this.

    The fuel only evaps when/where it is exposed to air, deeper inside the muffler you could have a lot of it still.
     
  9. wingstar

    wingstar XS400 Member

    Alright so tested it put, and it is a fouled plug as you suggested. I pulled off the spark plug wire on the left side and literally nothing happened. Bike was running the same.
     
  10. wingstar

    wingstar XS400 Member

    Alright I will keep this in mind, maybe I will take the exhaust off for now and let it air out a bit. I replaced both plugs just to be safe and now she runs like a dream
     
  11. amc49

    amc49 XS400 Addict

    Are you even able to think? If it is running right you have already tested the pipe to be working. Not to mention you would have already blown yourself up if it was going to happen. You are about a year too late with that.

    What are the schools putting out now for educated???? GEEZ.............
     
  12. wingstar

    wingstar XS400 Member

    You coulda just kept that to yourself. Pipe is fine, never said anything about it being broken. Looks like someone needs to do a bit ofreading comprehension lol
     
    xschris likes this.
  13. amc49

    amc49 XS400 Addict

    LOL I had the reading comprehension of past college exit when I was in the 7th grade.

    And if YOU reread the entire thread, you will find I never mentioned one word about a broken exhaust. We were worried about it being full of raw fuel, at least until you hit damaged synapses to go off into deep space. I seem to be all alone now.

    Look here, I'm trying to keep you from killing yourself and you witlessly lit the stick of dynamite anyway. Where I come from we don't call that smart. Not looking to hurt you at all but you need the shove, clearly not looking out for your own best interests. And then changing the post up to then make a wild claim about a broken pipe? I'm old but I'm not THAT old. Pull your head out.

    I'll leave you alone now, hoping you don't hurt yourself.
     
  14. wingstar

    wingstar XS400 Member

    "If it is running right you have already tested the pipe to be working."
     
  15. amc49

    amc49 XS400 Addict

    That in no way at all says the pipe was ever broken. You pulled english out of context to say that and as well ignored the greater part of the thread doing it.

    We were talking about a pipe that had the potential to be heavily clogged with vaporous and possible liquid fuel, which is not broken at all (at least until it explodes) but a definite safety issue. I guess that went right over your head. You even now seem to be more worried about proving your illogical thought than the fact that you but for the grace of God could have hurt yourself. I take note of the fact that a stupid little propane log fire starter leaked into a house to blow the entire home into toothpicks in the last day or so. I've seen muffler explosions rip off an entire exhaust pipe before. I've as well seen somebody trying to re-index a V-8 distributor back into the hole while having girlfriend bump the starter and the open fuel pump line sending small shots of fuel over engine to run into the hole. The distributor was wired up and at some point the points opened to flash arc and the whole thing exploded into the engine case to blow the friend some 15 foot backwards and both valve covers ripped completely off the engine to fly out like tissue paper. They never found the distributor, it landed out in field somewhere. I know of other more violent incidents.

    The danger is rare but extremely real when it happens.
     
    Last edited: Sep 25, 2020
  16. wingstar

    wingstar XS400 Member

    Sorry i misunderstood you saying the pipe was working, but the way you wrote id made it seem like it was broken in the first place. I took your warnings into consideration, im not stupid
     
  17. amc49

    amc49 XS400 Addict

    Enough said, nobody thinks you are stupid, but even people like me can do sometimes stupid things.
     

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