Ron Atchison RZ500 Needles

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rzatch
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#31 Post by rzatch » Tue May 22, 2012 11:15 am

aaronmvrider wrote:the 5L1 needle you refer to.... i take it that is the standard neele for rz 500.....No the standard needle is a Yamaha only part. The 5L1 is a standard Mikuni needle though that you can get from any Mikuni carb parts dealer for about 6.00 each.

i am not a machinist etc.... You don't have to be the slots that are in the 5L1 will work as is. The only thing you may have to do is add some washers for shims as I said. The top two slots on the 5L1 would normally be cut off anyway so they are of no use. The slots you would be concerned with are the bottom two and that is where I would add the new slots but normally the very bottom one wouldn't get used so that leaves you with the the bottom two slots as the needle comes and then you would add the washer to make the bottom third slot if need be. anyone on the board doing these needles.....



it is a rich area at 5500 revs.... right at cruising speed :sad: :sad:

Yes that is exactly what your going to fix
pulls like a train once through this area

i have pods on the ears.... lomas pipes.... standard ignition and carbs...

might be time to get the carbs apart and have a go at this....

it really has put me off riding the rz 500...... such a shame...



Fix it then!!!!!

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aaronmvrider
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#32 Post by aaronmvrider » Tue May 22, 2012 7:55 pm

4 x 5l1 needles delivered to australia.... $40.... in australia they are $13 ea plus delivery

economy cycles..... post was nearly half of the cost.... $17
my rides
rz 500 1984
2 x rz 350 1984
mv agusta f4 1000 2004

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rzatch
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#33 Post by rzatch » Wed May 23, 2012 12:23 am


Jeppe500
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#34 Post by Jeppe500 » Wed May 23, 2012 3:40 am

Tryed to order from them.....
Money sent but no needles delivered.
They never answered any mail :-(

Bought my needles here in Sweden.
Approx 10 Usd each inc. pp
//Jeppe

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Marsupilami
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#35 Post by Marsupilami » Wed May 23, 2012 5:39 am

Jeppe500 wrote:Bought my needles here in Sweden.
Approx 10 Usd each inc. pp
//Jeppe
May I ask from who? After reading this thread, I want to do the same mods. :)

Jeppe500
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#36 Post by Jeppe500 » Wed May 23, 2012 1:28 pm

Marsupilami wrote:
Jeppe500 wrote:Bought my needles here in Sweden.
Approx 10 Usd each inc. pp
//Jeppe
May I ask from who? After reading this thread, I want to do the same mods. :)
Bought both mainjets and needles from "Bra i gasen".
Ordered online at
www.braigasen.se (or .com)

//Jeppe

Bengt Weil
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Re: Ron Atchison RZ500 Needles

#37 Post by Bengt Weil » Fri Jun 13, 2014 8:55 pm

I ran across a source in the U.S. for the Mikuni 5L1 needle, priced at $4.75 each. I inquired about their jet listings and they say that if their listing says they are genuine Mikuni, they are - otherwise they are aftermarket. Here is the link to their genuine Mikuni 5L1 needles:

http://www.partsreloaded.com/index.php? ... l1&x=0&y=0

Hard to beat the price and the USPS mailing is reasonable when ordering multiple items. Probably a good source for other carb parts as well, as long as they are listed as genuine...

HWY9CA
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Re: Ron Atchison RZ500 Needles

#38 Post by HWY9CA » Sat Aug 09, 2014 10:41 pm

Here is another vendor
http://www.jetsrus.com/individual_parts/002_297_su.html" onclick="window.open(this.href);return false;
$7.04 ea

JT
http://www.rdsonly.com/
JT
1975 RD350B
1975 RD250B -rough
1979 RD400 Race bike- in process
1985 RZ500 - flame bike
1993 TZ250 4DP2- to be restored

dbcjmc
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Re: Ron Atchison RZ500 Needles

#39 Post by dbcjmc » Sun Oct 01, 2017 11:33 pm

Hi! I'm new to the forum here and this is my first-time post. A couple quick questions :

1. Removing the anodized portion on the needles is easy. Buy why? Just curious.
2. Cutting c-clip grooves looks a little more daunting, so I'm going the route of shims. Is it necessary to cut the tip of the needle to make it the same length at the stock needle? What happens if I don't snip it off?

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busa1300
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Re: Ron Atchison RZ500 Needles

#40 Post by busa1300 » Wed Sep 11, 2019 8:50 pm

I did the mod for my RZV and it cleared up the 5000-6000 flat spot beautifully....
still have work to get the 4000 and under powerband to run smooth yet.
from 4000 to 11000 it is worlds better.
Thanks for the tip.

Using Jolly Moto's and Uni's on the stock ears.
Zeel ignition
230 mains
78 GS1000E
80 KD80
82 Katana
84 RZ350
84 RZV500R
86 GSXR1100
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88 FZR1000
89 RGV250 VJ21 SP
90 RGV250 VJ22 SP
91 TZR250 3XV2 SP
96 RGV250 VJ23 T SP
99 RS250
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FlyingBoat
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Re: Ron Atchison RZ500 Needles

#41 Post by FlyingBoat » Sun Dec 08, 2019 3:12 pm

I have a set of RD500LC carbs coming from Netherlands, I don’t know the year or the jetting and the information wasn’t available only they were very clean in photos so...

When they arrive I’ll look inside one and find out, if N-8 I’m happy but if not I’ll be looking the parts or making the changes noted above to achieve the same result. Then the question ok that’s the stock setting, but way back in 1986 I bought Toomeys that came with new jetting kit, I can’t remember if it was needles and jets or just one or the other, I’m sure someone knows what they were, but that’s where I’d really want to go all stock just with jetting for expansion chambers. My bike ran great with the Toomeys and I was happy.
1985 RZ500S Sold
1985 52X/RZV Project

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FlyingBoat
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Re: Ron Atchison RZ500 Needles

#42 Post by FlyingBoat » Sun Dec 08, 2019 3:20 pm

I found this page has a lot of info...

http://rd500lc.free.fr/technics/jet_size_en.htm
1985 RZ500S Sold
1985 52X/RZV Project

MK
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Re: Ron Atchison RZ500 Needles

#43 Post by MK » Sun Dec 08, 2019 4:20 pm

Just that the text is not written by a French guy, but one from Germany that I happen to know quite well :-)

At least it's an authorized extract. The original is here:
http://rd350.gmxhome.de/jet_size_problem_english.pdf
Bye
Martin

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rzatch
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Re: Ron Atchison RZ500 Needles

#44 Post by rzatch » Fri Apr 10, 2020 2:16 pm

Main jets are a whole different subject. This
Mod is to clean up the midrange only. Depending on the specs of your engine will determine which slot you use. My engine has a stage 2 tune but others have used them on bone stock motors and they work fine.

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