Author Topic: Not impressed with jetting or Kymco.  (Read 9531 times)

zombie

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Re: Not impressed with jetting or Kymco.
« Reply #15 on: April 01, 2012, 01:06:58 AM »
Wanna Bet?
Tire pressure effects jetting...
"They have nothing in their whole imperial arsenal that can break the spirit of one Irishman who doesn't want to be broken."   Bobby Sands...

misfit77

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Re: Not impressed with jetting or Kymco.
« Reply #16 on: April 01, 2012, 01:25:41 AM »
well the weights, spring and muffler are no longer variables.

While tire pressure has effect I say its neglible. If jetting was that sensitive......I would have to jet twice a day one in the morning for cool temps and again in the evening for warmer temps.

Here is a pic of 38/115 jets, no shims. weights, spring, stock air box and homemade muffler. The plug looks fine, its the dam top speed that is bugging me.



This is same setup with 110 jet.



This is stock everything except muffler.

zombie

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Re: Not impressed with jetting or Kymco.
« Reply #17 on: April 01, 2012, 01:30:14 AM »
Something is WAY weird. The plug case is black, and the insulator is white.
Have you done a compression test? Adjusted the valves?
"They have nothing in their whole imperial arsenal that can break the spirit of one Irishman who doesn't want to be broken."   Bobby Sands...

zombie

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Re: Not impressed with jetting or Kymco.
« Reply #18 on: April 01, 2012, 01:31:43 AM »
Also a running vacuum test! If there is a vacuum leak in the intake system you will read weird fluctuations in the gauge
"They have nothing in their whole imperial arsenal that can break the spirit of one Irishman who doesn't want to be broken."   Bobby Sands...

misfit77

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Re: Not impressed with jetting or Kymco.
« Reply #19 on: April 01, 2012, 03:45:42 AM »
well I put a new plug in. That's why one looks new, but I was thinking the same thing. the original jets look like I was running rich while new jets look a little lean.

I double checked hoses and connections. Remember this scooter has 1800 or so miles...possibly Km. Things are new and untouched except by me.

wordslinger

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Re: Not impressed with jetting or Kymco.
« Reply #20 on: April 01, 2012, 03:50:35 AM »
Wanna Bet?
Tire pressure effects jetting...


..you best believe it CAN!!
..every mod (action) necessitates a (reaction) mod..

misfit77

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Re: Not impressed with jetting or Kymco.
« Reply #21 on: April 02, 2012, 02:42:05 AM »
"Here is a pic of 38/115 jets, no shims. weights, spring, stock air box and homemade muffler."

So what is the difference between your stock setup and your current setup.

What has been done to the intake that would need a 115 main jet.  And why does it look lean if your going up 13 on the main jet and your using the stock airbox.

Something is not right and your just gonna be frustrated with it.

Just put it back to stock if it runs better at stock.  ;)


Stock with ghetto muffler 60mph. Changed jets (38/110) and shimmed the needle...scoot got slower, about 58 on speedo. Removed air box lid  and scoot would go maybe 62mph. Removed shims, reinstalled lid. Added dr pulley and yellow spring... 62 mph. Tried 115 jet, 62mph.

Just seems like something holding me back. Does the CDI have a limiter?

zombie

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Re: Not impressed with jetting or Kymco.
« Reply #22 on: April 02, 2012, 03:55:47 AM »
Your bottle neck may be in the rear gears. What is the tire size, and final drive ratio? What rpm's are you at (wot).
You've said "homemade muffler" Pipes are KEY to power. They are designed to make power at certain rpm's/temp. Maybe your Ghetto pipe is at fault.
"They have nothing in their whole imperial arsenal that can break the spirit of one Irishman who doesn't want to be broken."   Bobby Sands...

misfit77

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Re: Not impressed with jetting or Kymco.
« Reply #23 on: April 02, 2012, 07:13:59 PM »
these are definelty WOT values....the last 1/4 turn or so do not seem to do much.

My muffler uses a small diameter pipe and a baffled kawasaki muffler. It might to restrictive.

Gearing?....you got me.

old mod

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Re: Not impressed with jetting or Kymco.
« Reply #24 on: April 02, 2012, 09:12:21 PM »
Kymco 125/150 is geared to do about 60-65 wot. i did a 170 big bore it was fast but only got to 68 indicated before it destroyed itself! and at that speed the belt was climbing over the cvt. If anyone knows how to change the final drive gearing i'm interested

misfit77

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Re: Not impressed with jetting or Kymco.
« Reply #25 on: April 02, 2012, 11:45:48 PM »
speaking of...I calipered the amount of untraveled variator...I have about .25 left"

Too soon to see if the dr pulley did anything.


Also, I am just disappointed becuase my old cheapo Tank 150 hauled ass with less time an money invested.
I never jetted the carb and I know that it lasted 2 more owners before I lost track.

zombie

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Re: Not impressed with jetting or Kymco.
« Reply #26 on: April 03, 2012, 02:23:53 AM »
Kymco 125/150 is geared to do about 60-65 wot. i did a 170 big bore it was fast but only got to 68 indicated before it destroyed itself! and at that speed the belt was climbing over the cvt. If anyone knows how to change the final drive gearing i'm interested
Try Louie at http://www.spi-parts.com/ Mention the forum for 10% off your order. I worked real hard to get us the discount
"They have nothing in their whole imperial arsenal that can break the spirit of one Irishman who doesn't want to be broken."   Bobby Sands...

zombie

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Re: Not impressed with jetting or Kymco.
« Reply #27 on: April 03, 2012, 02:28:58 AM »
speaking of...I calipered the amount of untraveled variator...I have about .25 left"

Too soon to see if the dr pulley did anything.


Also, I am just disappointed becuase my old cheapo Tank 150 hauled ass with less time an money invested.
I never jetted the carb and I know that it lasted 2 more owners before I lost track.
.25" is not bad but you should find out why you have extra room. I would remove the contra spring, and re assemble the parts loosely. You can the manually open the torque drive to see if the belt has enough travel. Could be too short. Could also be the Drive boss is too long, or the rollers are worn too far/too light. Check the torque drive first to verify it works, and the belt is long enough... Don't assume.
"They have nothing in their whole imperial arsenal that can break the spirit of one Irishman who doesn't want to be broken."   Bobby Sands...

misfit77

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Re: Not impressed with jetting or Kymco.
« Reply #28 on: April 03, 2012, 02:59:29 PM »
hmmmm good idea about the belt.

Taken else apart....I think.


I will check belt p/n later this week. I do know the current one is a kymco part, but that means not much.

zombie

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Re: Not impressed with jetting or Kymco.
« Reply #29 on: April 04, 2012, 08:18:22 AM »
 I do know the current one is a kymco part, but that means not much.

Now you got it!
"They have nothing in their whole imperial arsenal that can break the spirit of one Irishman who doesn't want to be broken."   Bobby Sands...

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