korider.com | Hyosung Motorcycle Owners Forum

korider.com | Hyosung Motorcycle Owners Forum

  • July 17, 2018, 12:29:35 PM
  • Welcome, Guest
Please login or register.

Login with username, password and session length
Advanced search

News:

Welcome to Korider.com!

Pages: 1 2 3 [4]

Author Topic: Misfire  (Read 2112 times)

umop-ǝpisdn

  • Global Moderator
  • Forum Addict
  • *****
  • Online Online
  • Posts: 7149
Re: Misfire
« Reply #30 on: December 01, 2017, 08:18:50 PM »

That's pretty damn serious actually.

..where did you get such exotic valves from by the way?
Logged
I used to be a sensitive, new age guy, but times have changed and now I am more of a caring, understanding, ninties type.

Register and log in and the Ads below will be gone! :D

BikeBandit.com

Rider97

  • Training Wheels
  • *
  • Offline Offline
  • Posts: 12
Re: Misfire
« Reply #31 on: December 03, 2017, 06:31:46 PM »

had this issue before, kept getting worse till my rear cylinder wouldn't even fire anymore, rinse the tank through, change filter, rip the carbs apart and clean them, just make sure you don't break the pipe between the two float bowls because it's a right bastard. Give it a little heat and use a small flathead screwdriver. And it also costs a bit for a tiny pipe.

I feel it's efi then it's defo electrical.
Logged

Cloud

  • Korider's Fastest GT125R.
  • Forum Addict
  • *****
  • Offline Offline
  • Posts: 2523
  • Head removal specialist.
Re: Misfire
« Reply #32 on: December 05, 2017, 12:08:05 PM »


Valves came with the engine. I got it from some workshoppy type guy who was putting it together for racing, but I got the lump cheap because the tensioner failed in the front so they switched to Suzuki engines or something.

I'm not too worried about the scuffs in the bore. If they're all doing it, then it's normal enough, if a bit... odd. Did no-one at Hyosung R&D ever think to see if the valves were whacking the bores? Pretty fundamental.

*

I'm convinced the problem is electrical. Did your rev needle drop out every time it misfired?

I cannot stress this enough:
the needle is not dropping simply because of the engine speed reducing as a result of a misfire, it's switching off, like hitting the killswitch, but doesn't go all the way to the bottom so it's not actually killswitching itself. The bike only misses a single bang at a time, but the needle flicks way down.

Could this possibly be anything other than electrical?
Logged

Rider97

  • Training Wheels
  • *
  • Offline Offline
  • Posts: 12
Re: Misfire
« Reply #33 on: December 09, 2017, 12:41:46 AM »

I did have another problem with the older 125 I had, sept that one has the digital clocks (same engine; I put that into the latest bike) the old one did have some electrical issues, especially in the crappy weather; the needle would drop out; and sometimes even spazz out, the engine would hunt at idle like every other 4 or 5 cycles then dip and recompose (wasn't carbs) AND MISSFIRE when throttling up;  I eventually tracked all these problems down to the connectors on the cdi box; the middle one if i remember correctly; but I took both off leaving the clock connected. This became common procedure for a while, wd 40 fixed the problem every time. I also re did the coil connections.
Logged

umop-ǝpisdn

  • Global Moderator
  • Forum Addict
  • *****
  • Online Online
  • Posts: 7149
Re: Misfire
« Reply #34 on: December 09, 2017, 12:34:45 PM »

AFAIK the tacho reads from the front cylinder.

If power or signal(ground) to the coil is interrupted, then the tacho would indeed see a stationary motor.
Logged
I used to be a sensitive, new age guy, but times have changed and now I am more of a caring, understanding, ninties type.

Cloud

  • Korider's Fastest GT125R.
  • Forum Addict
  • *****
  • Offline Offline
  • Posts: 2523
  • Head removal specialist.
Re: Misfire
« Reply #35 on: December 11, 2017, 01:06:17 PM »

AFAIK the tacho reads from the front cylinder.

If power or signal(ground) to the coil is interrupted, then the tacho would indeed see a stationary motor.

I'm still waiting for gaskets to arrive.

It's been months. I've paid hundreds and hundreds to insure and make-legal a bike that I can't use because some cack-fingered gimbophiliac took three shitting weeks to put something in the slow-ass mail.
Logged

Pages: 1 2 3 [4]