Introduction & question

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pendrecht
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Joined: Tue Nov 07, 2017 4:39 am

Introduction & question

#1 Post by pendrecht » Tue Nov 07, 2017 12:47 pm

Hi All,

My first name is Gerard and I am currently quite busy with a liquid cooled two-stroke Zundapp enigine.

It is a Zundapp KS125 LC with a big-bore cilinder of 154CC, tailormade exhaust, membrane and poort mapping has been change and a VM 28 Minuni carburetor. The tuning looks a lot like a RD 350 cilinder.

My question is can any help me out with the dimension of the below mentioned Needles acc to attached picture.
4H16
4N10
5CK2
5K1
5L20


That would be most helpfull.

regards

Gerard
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Needle Mikuni.png
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Palolo
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Re: Introduction & question

#2 Post by Palolo » Tue Nov 07, 2017 5:06 pm

I thought I could help but I couldn't find any of those needles in various charts. Here's an example: http://www.pjmotorsports.com/mikuni-jet-needles.html" onclick="window.open(this.href);return false;

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T.RexRacing
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Re: Introduction & question

#3 Post by T.RexRacing » Wed Nov 08, 2017 12:15 am

Same here. Cannot find anything on any of those numbers posted. Where did you find them?
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MK
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Re: Introduction & question

#4 Post by MK » Thu Nov 09, 2017 5:42 pm

The last 3 needles are RD350LC, YPVS '83 and YPVS '86.
The 5L20 is richer than the 5K1.
I guess "measuring" them will not be helpful as a vernier will not be enough and depending on temperature or calibration differnt measurements will be a few 1/100 mm off.
On the needle jet about 5/100 mm is the difference between two sizes like N-8 and N-6.

Here's some other needles:
http://www.sudco.com/images/Tuning%20Je ... pg%202.jpg" onclick="window.open(this.href);return false;

Here a general info:
https://thumpertalk.com/forums/topic/12 ... -decoding/" onclick="window.open(this.href);return false;

If you need advice on the KS125 try here:
https://www.facebook.com/groups/7367893 ... 2/?fref=ts" onclick="window.open(this.href);return false;
Bye
Martin

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