Ron Atchison RZ500 Needles

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smurph
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Ron Atchison RZ500 Needles

#1 Post by smurph » Mon Mar 30, 2009 10:16 pm

Ron Atchison was kind enough to provide his needle instructions.

It's useful info like this that makes this site what it is.

Thanks Ron!

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Fuel Injected RZ350

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rzatch
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#2 Post by rzatch » Mon Mar 30, 2009 10:56 pm

As you can see there are two different needles for the N-8 or 0-0 jets. These are also being sold as A&B jets. As a rule of thumb the 84's had the 0-0 and the 85's had the N-8's. But there were transition year bikes that were sold as 85's that had the 84 jetting so to be sure it's best to check your carbs. :grin:

Masterbill
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#3 Post by Masterbill » Tue Mar 31, 2009 9:29 am

Hello,

Any more information please?

Are these needles like Ivan's - do they do they same sort of job etc.

Cheers
RZV 500R .... I had one for 13 years
Thundercat Brakes.
Stan Stevens Stage 3
BDK ignition
Nikon Pipes .

350 F2 Zeeltronic, kenny's pipes, PWK,s

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rzatch
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#4 Post by rzatch » Tue Mar 31, 2009 10:53 am

I knew this was going to come up and it's why I have held off in offering this information but to answer your question. Yes and No. These were developed almost two years before Ivan started selling his but I don't want to go into all of that. I'm sure Gus can understand that end of it..... So if we can, lets just keep this as an option to make your own or have someone else do the machining and still be money way ahead.

I don't know what more info you want, maybe these links will help out. If not let me know what it is you need.

http://home.comcast.net/~rzmike/id17.htm

http://www.rzrd500.com/500phpBB3/viewto ... 37c2f0f355

Masterbill
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#5 Post by Masterbill » Tue Mar 31, 2009 11:18 am

Hello,

Thanks for the info - I don't need to know anymore. Just curious thats all.

Cheers
RZV 500R .... I had one for 13 years
Thundercat Brakes.
Stan Stevens Stage 3
BDK ignition
Nikon Pipes .

350 F2 Zeeltronic, kenny's pipes, PWK,s

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rzatch
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#6 Post by rzatch » Tue Mar 31, 2009 12:22 pm

:smt023

trix
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#7 Post by trix » Tue Mar 31, 2009 6:29 pm

Hi Ron
I have a few questions. Hope you dont mind!

I have N-8 jets in my 1984 RZ.

Whats the purpose of removing the anodising; is it just to reduce the diameter of the needle?

If it is possible that the modified needles could work on the 3rd clip of the "new" 5 clip positions, then its possible that you could make this work without machining new clip grooves; i.e. run it in the lowest existing groove?? (the implication being that I could make these without machine tools?)

A further question based on your link to an archived thread. I have a standard engine with Jolly Motos. If I wanted to run pod filters (straight onto the carbs) would these needles and 230 mains be a good starting point?

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rzatch
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#8 Post by rzatch » Tue Mar 31, 2009 8:58 pm

1. yes

2. yes you could you may just get lucky! If it's not right then you could go the machining route. Either way you have to take the carbs apart don't you. :sad:

3. yes, but pod filters right into the carbs has caused a lot of people grief. Unless you just have to have them a better route to go is to use the ears and a Uni filter on each ear, part #UP-4229 will fit perfectly.

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#9 Post by adr1an » Tue Mar 31, 2009 9:24 pm

Hi Ron,
Are there any real benefits running the unifilter pods rather than the standard filter apart from maybe the induction noise?
If using a set of Jolly's or JL's which you need to rejet for, I assume you would require further jetting for the unifilters?
What might you recommend?

Many thanks,
Adrian

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rzatch
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#10 Post by rzatch » Tue Mar 31, 2009 10:19 pm

Yes, they allow the motor to breath, there's not as much induction noise as you might think as your still using the ears. As you know a engine is nothing more than an air pump. Allowing your motor to breath better will also make your exhaust system more efficient. Without changing anything on the intake side a simple 1 or 2 jet size increase on the mains is all you would need with a set of pipes. But with intake changes then the game starts over and then you need to start using bigger jets like in the 220 range for starters with a stock motor. When I was using stock bored carbs and a stage 2 tune I was running 260 mains with Jolly pipes and Uni filters.

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#11 Post by Luther » Thu Apr 02, 2009 4:16 pm

There are several things that control fuel flow at closed throttle to about 1/8th throttle like Pilot Jet, Pilot Air Jet, Slide Cutaway, Float Bowl Level, Annular Orifice between Needle top straight diameter and Needle Jet. Leaning any of these out could help get rid of the rough running at idle and just off idle. Its been found that a larger needle helps best without causing problems somewhere else.

Here are all the original jetting specs I have found.

Main Jet 195 (1984) 165 (1985)
Main Air Jet 1.8 upper cyl, 1.6 lower cyl for all years
Needle 5LT14-3 for all years
Needle Jet O-0 (1984) N-8 (1985)
Pilot Jet 22.5 for all years
Pilot air Jet 1.1 (1984) 1.4 (1985)
They don't have Mixture Screws

Here is a link with Mikuni 5 series needles.

http://www.geocities.com/mraxl/carb/mikunineedle.html

The Y dimension is the length from the top of the needle to where the taper starts. The stock 5LT14-3 are about 23mm. Only one of the needles on the list has a short Y. They are not available. Less than 10 of the 29 on the list can be bought through Sudco.

The 10 dimension is the straight top diameter of the needle. My stock 5LT14-3 needles measure 2.515mm and my Ivan's needles measure 2.535mm. Thats the same as 4 needle jet sizes. Ron modified the taper to start early on needles with a larger top straight diameter because its cheaper than needle jets that probably aren't available.

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#12 Post by rzatch » Thu Apr 02, 2009 9:44 pm

A set of 4 can be bought at Parts Unlimited for $18.00. :grin: Even if you have to pay someone to cut the new slots for you at say $10.00 a needle, which is probably on the high side your going to save a ton of money and have better running bike. Then with the extra money you saved you can get in on the raffle Gus started. Just think all of that for under a hundred bucks! :grin: :grin: Now that's a real triple play!

http://offroad.parts-unlimited.com/16/254/6340844

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#13 Post by trix » Fri Apr 03, 2009 5:07 pm

Luther; am I right in thinking that the main air jets cannot be removed?

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#14 Post by Luther » Mon Apr 06, 2009 12:39 pm

Well there not supposed to but i'm going to try anyway. :grin:

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#15 Post by aaronmvrider » Mon Apr 06, 2009 6:59 pm

3. yes, but pod filters right into the carbs has caused a lot of people grief. Unless you just have to have them a better route to go is to use the ears and a Uni filter on each ear, part #UP-4229 will fit perfectly.
G'day
with this air box / ears set up does this mean you retain the ears and dont install the center box ?

if so where do i look to purchase these air pods to fit onto the ears, what brand is the part number from

any photos ?? sounds like a route i would like to take i am running lomas pies but i believe the standard jets (165) are still in carbs from previous owner but he seems to think they (jets) have been drilled might be safer to purchase a new set of 230's etc..

Cheers
Aaron
my rides
rz 500 1984
2 x rz 350 1984
mv agusta f4 1000 2004

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