89 RZ 350 CDN

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troyg143
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89 RZ 350 CDN

#1 Post by troyg143 » Sat May 14, 2016 1:22 pm

Looking for some help with jetting suggestions on an RZ with the following; 1UA Carbs, Wicked pipes, 2 into 1 air filter, Cool head with 22cc domes? Currently has 420 mains, 27.5 pilots. Thx!

troyg143
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Re: 89 RZ 350 CDN

#2 Post by troyg143 » Tue May 17, 2016 12:16 pm

Ok....Getting an education on 1UA cylinders and carbs...Going to go down to a 320 main and try 25 pilots...also have the 4 degree plate in to advance the timing...any comments would be appreciated!

Misfitmechanic
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Re: 89 RZ 350 CDN

#3 Post by Misfitmechanic » Tue May 24, 2016 4:17 pm

I'm currently putting a 1988 rz350 together and I'm also looking for some jetting advice for the 1ua power jet carbs. My bike currently has a 27.5 pilot (stock) and 230 mains. I'd like to find a good go to size and jet down from there.

evan_calgary
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Re: 89 RZ 350 CDN

#4 Post by evan_calgary » Tue May 24, 2016 6:18 pm

Troy. provide your location or at LEAST altitude. Carbs require different jetting based on altitude.

troyg143
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Re: 89 RZ 350 CDN

#5 Post by troyg143 » Sat May 28, 2016 11:08 am

Sorry...I am in Edmonton at 2000' elevation. thx for reply

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Off Road
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Re: 89 RZ 350 CDN

#6 Post by Off Road » Sat May 28, 2016 9:19 pm

Misfitmechanic wrote:... the 1ua power jet carbs in stock trim would have been 185 mains, 60 left power jet, 65right power jet, 27.5 pilots and needle clip on the second from the top...
At WOT the Main and Power jets add to give a total of 245 left, and 250 right in the 1UA carbs.
The stock Main jet on the 31K carbs is 240.

On my bike with 31K carbs, Toomey pipes & Y-boot, I'm running 420 main jets, 25 pilots, 5K1 needle on the 4th clip with a washer under the clip.
My elevation is 3500'.

Since the power jet is adding 60 to the main jet size, then I would start with 360 main jets in the 1UA carbs.
(360 + 60 = 420, same as the 31K carbs)

The clip on your needle has already been lowered 1 position from stock, so this will make the mid-range richer.

I would leave the needles where they are and see how they work. Better to have it running rich.

Note: I am Not a mechanic or engine tuner. This information is just my best guess. Use at your own risk. :smt003

troyg143
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Re: 89 RZ 350 CDN

#7 Post by troyg143 » Sun May 29, 2016 12:55 pm

Cool....I am just waiting on new exhaust gaskets and once I have those will try 360 mains and let you know. Thx!

Forzfed
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Re: 89 RZ 350 CDN

#8 Post by Forzfed » Wed Jun 01, 2016 11:35 pm

Misfitmechanic wrote:I'm currently putting a 1988 rz350 together and I'm also looking for some jetting advice for the 1ua power jet carbs. My bike currently has a 27.5 pilot (stock) and 230 mains. I'd like to find a good go to size and jet down from there.
What all is done to the engine? I'm running 410's with 22.5 pilots and 4th clip, that gives me the power jet mid range, when you just get into the throttle in 3rd gear or higher at a little over 6K and it just keeps pulling and pulling like a big cc bike. This is stock with the toomey pipes and y-boot. Elevation here is around 700ft but the weather machine will record as low as 800ft below sea level on a cold day.
90 RZ Race Bike
86 RZ daily driver
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troyg143
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Re: 89 RZ 350 CDN

#9 Post by troyg143 » Mon Jun 06, 2016 1:58 am

If you have 1UA carbs like all CDN bikes, they have a powerjet and do not require such a large main. My mistake was reading these forums and not recognizing that the pre 85 bikes in the USA have a 31k carb with no powerjets. So, most tech tips do not put these powerjets [ 60] into consideration?

evan_calgary
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Re: 89 RZ 350 CDN

#10 Post by evan_calgary » Mon Jun 06, 2016 9:25 pm

Good to see another Alberta member. Lots of us around! I have not spent enough time with carbs but had enough knowledge to know the mains should not fall out when taking off a float bowl working on my project yesterday :)

RuZty
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Re: 89 RZ 350 CDN

#11 Post by RuZty » Tue Jun 07, 2016 8:10 am

troyg143 wrote:If you have 1UA carbs like all CDN bikes, they have a powerjet and do not require such a large main. My mistake was reading these forums and not recognizing that the pre 85 bikes in the USA have a 31k carb with no powerjets. So, most tech tips do not put these powerjets [ 60] into consideration?
Actually all non-US bikes up to and including '85 (31K model bikes) have non power jet carbs. The US bikes had different carbs, pipes and cylinders (48H model) to satisfy the EPA.

Forzfed
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Re: 89 RZ 350 CDN

#12 Post by Forzfed » Tue Jun 07, 2016 3:47 pm

I'm use to tuning with a laptop on my car. You don't need a big main. For some reason my bike doesn't pull well on the top with out a bigger main. Smaller mains makes my bike feel like a stocker. With the big mains it pulls the tires off the ground in 4 gears. Going to have to take it to the drag strip and test it. Those numbers don't lie.
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two-stroke-brit
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Re: 89 RZ 350 CDN

#13 Post by two-stroke-brit » Tue Jun 07, 2016 7:23 pm

Forzfed wrote:I'm use to tuning with a laptop on my car. You don't need a big main. For some reason my bike doesn't pull well on the top with out a bigger main. Smaller mains makes my bike feel like a stocker. With the big mains it pulls the tires off the ground in 4 gears. Going to have to take it to the drag strip and test it. Those numbers don't lie.
DYNO is your friend :smt023
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Forzfed
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Re: 89 RZ 350 CDN

#14 Post by Forzfed » Wed Jun 08, 2016 3:54 pm

two-stroke-brit wrote:
Forzfed wrote:I'm use to tuning with a laptop on my car. You don't need a big main. For some reason my bike doesn't pull well on the top with out a bigger main. Smaller mains makes my bike feel like a stocker. With the big mains it pulls the tires off the ground in 4 gears. Going to have to take it to the drag strip and test it. Those numbers don't lie.
DYNO is your friend :smt023
Dynos are only accurate if you put in all the proper correction factors, but if the operator knows what they are doing they can be very accurate. There is one of the car dyno shops here that inflates everyones rwhp. They show up at the drag strip brag about the power they put down and run a pathetic 1/4 mile. When you ask these people what is done to their car, it has all the little stuff like exhaust, intake and tune.
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OldTZracer
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Re: 89 RZ 350 CDN

#15 Post by OldTZracer » Sat Jun 11, 2016 7:22 pm

360s should be a safe starting point for around here. You may end up coming down a few sizes, but jets are cheaper than pistons... You'll probably end up juggling pilot sizes & needle position to smooth out the midrange transition.
"...its a 2-stroke ya twit - Its supposed to smoke..."

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