« previous next »
Pages: [1]

Author Topic: Unknown issue at 30mph+  (Read 1802 times)

ParaIndiana

  • Jr. Member
  • **
  • Posts: 66
    • View Profile
Unknown issue at 30mph+
« on: November 06, 2014, 06:52:52 AM »
Ok. I have a problem that I cannot figure out. I have great acceleration from 0-30. Nothing any different than it has ever been. As soon as I get near 30mph, (on the flat, up hill, down hill, it doesn't matter), it starts missing out badly. Even then it is still making power enough to eventually get me near my usual top speed. I pre-mix, and have not changed the ratio at all. I have taken the carb apart and thoroughly cleaned it even though I have recently done that. I still have great compression. The plug has about 500 miles on it and doesn't look terrible at all. The reeds are new within about 500 miles as well. The only things I haven't checked is an air leak or the fuel filter. Can anyone point me to something obvious that I might be missing?  Build details are current in the sig.
Logged
2011 Kymco Like 50 2t
Malossi 70 BBK
Malossi 19MM Carb
Stage 6 Sport Pro Clutch
Pod air filter
Malossi CF Reeds
Polini torque spring: Blue
Naraku Sport Variator
Naraku Sport Torque Driver
Naraku Half Pulley
5.5G Dr. Pully Sliders
Stage 6 +15% Primary Gear Kit
Malossi Belt
Pre-mix Fuel  45:1

BettinANDlosing

  • Hero Member
  • *****
  • Posts: 2235
  • Carter Merz
    • View Profile
    • Columbia Scooters
Re: Unknown issue at 30mph+
« Reply #1 on: November 06, 2014, 07:03:16 AM »
Sounds like a cdi issue possibly. If its cutting out like that and was running fine before. Does it do it without load like on the center stand?
Logged
2002 Kymco B&W 300; MRP 78MM "300CC", Naraku cam, Yoshimura rS3 exhaust, 17g Sliders, Yellow torque spring drilled airbox, stock carb #115 main #40 pj.

2001 "Yamaha" Zuma AKA MBK Booster; MHR OverRange, Dellorto 19mm BHBG, Polini "big" intake, RS-3 Rear shock, Stock cylinder.

ParaIndiana

  • Jr. Member
  • **
  • Posts: 66
    • View Profile
Re: Unknown issue at 30mph+
« Reply #2 on: November 07, 2014, 02:21:50 AM »
It's been rainy and cold, so I haven't had a lot of time to get out and mess with it. I haven't put it up on the center stand and run it out to see if it has the same issue yet, but I will as soon as I get a chance. I would guess that load makes no difference just from riding it.  It's always right at 30mph. If I back out of the throttle I can get it to smooth out. My RPM before the issue max out at WOT top speed at about 11k. Cruising good at about 8k RPM. The issue seems to be RPM related. It just so happens that 30mph corresponds to around 8500 rpm, under load or not. So my guess is a center stand test will prove this.
Logged
2011 Kymco Like 50 2t
Malossi 70 BBK
Malossi 19MM Carb
Stage 6 Sport Pro Clutch
Pod air filter
Malossi CF Reeds
Polini torque spring: Blue
Naraku Sport Variator
Naraku Sport Torque Driver
Naraku Half Pulley
5.5G Dr. Pully Sliders
Stage 6 +15% Primary Gear Kit
Malossi Belt
Pre-mix Fuel  45:1

BettinANDlosing

  • Hero Member
  • *****
  • Posts: 2235
  • Carter Merz
    • View Profile
    • Columbia Scooters
Re: Unknown issue at 30mph+
« Reply #3 on: November 07, 2014, 02:52:42 AM »
Yeah i would look into getting a new CDI. sounds like a timing issue. How many miles on the bike?
Logged
2002 Kymco B&W 300; MRP 78MM "300CC", Naraku cam, Yoshimura rS3 exhaust, 17g Sliders, Yellow torque spring drilled airbox, stock carb #115 main #40 pj.

2001 "Yamaha" Zuma AKA MBK Booster; MHR OverRange, Dellorto 19mm BHBG, Polini "big" intake, RS-3 Rear shock, Stock cylinder.

ParaIndiana

  • Jr. Member
  • **
  • Posts: 66
    • View Profile
Re: Unknown issue at 30mph+
« Reply #4 on: November 07, 2014, 03:15:15 AM »
Just under 4000 miles.
Logged
2011 Kymco Like 50 2t
Malossi 70 BBK
Malossi 19MM Carb
Stage 6 Sport Pro Clutch
Pod air filter
Malossi CF Reeds
Polini torque spring: Blue
Naraku Sport Variator
Naraku Sport Torque Driver
Naraku Half Pulley
5.5G Dr. Pully Sliders
Stage 6 +15% Primary Gear Kit
Malossi Belt
Pre-mix Fuel  45:1

ParaIndiana

  • Jr. Member
  • **
  • Posts: 66
    • View Profile
Re: Unknown issue at 30mph+
« Reply #5 on: March 22, 2015, 08:07:37 PM »
Just to close out this thread out with the fix. I discovered that not all new plugs are necessarily good plugs. Good thing I bought a set of 3. Swapped plugs, and the issue went away. Just to be sure, I put the other plug back in. Problem returned. Same brand. Same gap. The bad plug had about 10 miles on it, and every one of those miles it gave me troubles.

And stay tuned...I'll be adding to my other main thread soon as I'm expecting a few new springtime goodies to add to my build. 
Logged
2011 Kymco Like 50 2t
Malossi 70 BBK
Malossi 19MM Carb
Stage 6 Sport Pro Clutch
Pod air filter
Malossi CF Reeds
Polini torque spring: Blue
Naraku Sport Variator
Naraku Sport Torque Driver
Naraku Half Pulley
5.5G Dr. Pully Sliders
Stage 6 +15% Primary Gear Kit
Malossi Belt
Pre-mix Fuel  45:1

An Error Has Occurred!

Call to undefined function split()
Back