Jetting question RZ350

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zorba75482
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Re: Jetting question RZ350

#151 Post by zorba75482 » Mon May 25, 2015 4:40 pm

Finally got some time to ride again. Bike runs fine for a while at all revs and loads but after wide open throttle for about 10 seconds seems to lose power. Initially thought was seizing but checked plugs and they are fine. Good color. Starts right up after a minute or so and runs like a top again for as long as necessary up to 5000 rpm. But when nailed again I get the same symptoms. Did plug chops while suffering symptoms and both plugs clean and dry. Tried opening filler cap while suffering symptoms to no avail. Tried running on prime but same problem. Continues to be down on power until stopped and switched off for a couple of minutes. Will occasionally pick up when holding throttle open as if it is electrical and is intermittently trying to fire. Swapped plug leads but same problem. Beginning to think coil or cdi. Any theories appreciated
Steve

RZ350 1984 project D&Gs, Y Boot
Laverda 750 SF2 1974
BMW R90S 1974
Ducati GT1000 2009

silverstrom
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Re: Jetting question RZ350

#152 Post by silverstrom » Mon May 25, 2015 6:36 pm

Being an 84 it is very likely the CDI. Your symptoms are typical for early CDI failure.

zorba75482
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Location: Texas

Re: Jetting question RZ350

#153 Post by zorba75482 » Tue Sep 13, 2016 10:31 pm

Resurrecting this old issue as I finally have time to get back on this project. before I fork out for a new CDI I thought I would check coils and stator.
not even sure if I have the right components so here is what I found.

Generator. 29L-50-03200-3441-1DZ
CDI 29K-50
Stator 1DY

I checked against a compatibility table I found here but 1DY or 29K-50 is not mentioned

checked pick up coil at 115 Ohms
Charge coil 0.8 ohms
Source coil
Red/Brown 5.1 ohms
brown/green 168 ohms

Here's the kicker. I checked the ignition coil and found the test on primary between both sides or pigtail 0.5 ohms using the 200 ohm range on multimeter. Problem is when I test pigtail to one of the plug caps I am reading an open circuit on the 2000 or 20K meter setting. Surprised to see this as I am getting a spark and decent running for a while..

Would appreciate any thoughts as I don't know if to buy a coil or CDI or both or neither!
Steve

RZ350 1984 project D&Gs, Y Boot
Laverda 750 SF2 1974
BMW R90S 1974
Ducati GT1000 2009

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two-stroke-brit
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Re: Jetting question RZ350

#154 Post by two-stroke-brit » Wed Sep 14, 2016 8:09 am

Hey Zorba where are you in Texas ?
i am in Houston.
mark
350LC,Athena 392 big bore,stock porting,swiss cheese air box,stock reeds,spec11 pipes.(now TSA big bore pipes)
She might not be pretty but she will always be a fun ride


1982 YAMA RD350LC
98KDX 220R
1967 TRIUMPH TIGER
2001 TRIUMPH TT600

zorba75482
Posts: 112
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Re: Jetting question RZ350

#155 Post by zorba75482 » Wed Sep 14, 2016 8:45 am

two-stroke-brit wrote:Hey Zorba where are you in Texas ?
i am in Houston.
mark

Mark. I am in Sulphur Springs, East Texas
Steve
Steve

RZ350 1984 project D&Gs, Y Boot
Laverda 750 SF2 1974
BMW R90S 1974
Ducati GT1000 2009

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two-stroke-brit
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Re: Jetting question RZ350

#156 Post by two-stroke-brit » Wed Sep 14, 2016 2:08 pm

Hi Steve, up by Dallas eh.
I think there are a couple of members in the DFW area.
that might be able to help
hopefully one will chime in.
mark
350LC,Athena 392 big bore,stock porting,swiss cheese air box,stock reeds,spec11 pipes.(now TSA big bore pipes)
She might not be pretty but she will always be a fun ride


1982 YAMA RD350LC
98KDX 220R
1967 TRIUMPH TIGER
2001 TRIUMPH TT600

zorba75482
Posts: 112
Joined: Tue Mar 12, 2013 11:50 pm
Location: Texas

Re: Jetting question RZ350

#157 Post by zorba75482 » Sun Sep 18, 2016 3:51 pm

Anyone have thoughts on ignition coil test results. Bike starts an revs but won't pull away with any load
Steve

RZ350 1984 project D&Gs, Y Boot
Laverda 750 SF2 1974
BMW R90S 1974
Ducati GT1000 2009

zorba75482
Posts: 112
Joined: Tue Mar 12, 2013 11:50 pm
Location: Texas

Re: Jetting question RZ350

#158 Post by zorba75482 » Sat Jun 24, 2017 11:47 pm

Still persevering. New dyna coil CDI checked good by running in another bike. Runs fine until sustained running over 5k. Going through carbs again. HavecY boot with 420 mains. Dynojet needles on 2nd clip from top.
Sound about right?
Steve

RZ350 1984 project D&Gs, Y Boot
Laverda 750 SF2 1974
BMW R90S 1974
Ducati GT1000 2009

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pushstartrearset
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Re: Jetting question RZ350

#159 Post by pushstartrearset » Tue Jun 27, 2017 12:41 pm

I've always thought the DGs ran leaner on the mains than the toomey pipes. Never really found any solid jetting advice for DGs. I suspect and highly recommend changing to old school or new toomeys. I wasn't satisfied w/ Spec II pipes on the RZ either.

I did find one post on a banshee forum where a guy was running 310 main jets w/ 4th clip (rich) on his banshee.

That misfire could be from too much fuel up top. (could explain why the CDI / coil swap had no effect) did you every pull out the needle jets (physical removal from carb) to see if they weren't gunked up also? check also the connection by under right side cover that goes to stator...I had a real bad or frayed? connector there. the RZ carb also has a very weird horizontal passage (emulsion tube/ 3-way skinny ass passageway..EASY to miss...you need to check that!!!) that goes from the tiny hole in the side overflow in the carb body (not bowls) horizontally to the needle jet tunnel (if you look inside the NJ tunnel w/ NJ removed, you'll see the tiny hole in the side that eventually leads out to the side overflow), if this is clogged like our 84 was...you need to chemically soak and then compressed air blow the passage out...took me a year to figure out that fiasco...same symptoms as yours...see if i can find the old link.

viewtopic.php?p=70127#p70127



DISCLAIMER: I don't want to recommend a jetting change I haven't tried, so might be a good idea to hear from a few other people to see, but if they all agree on something, I'd go w/i. Not responsible if motor blows. Just still BAFFLED that there isn''t a shitload of detailed jetting info on DG pipes...wtf?
Last edited by pushstartrearset on Tue Jun 27, 2017 1:07 pm, edited 2 times in total.
1984 RZ350L (U.S.) Old Toomeys, oil injected!, Y-boot K&N. loctite throttle cable holder on left carb!! , 410 mains, Dynojet needles 2.0 clip, #20 pilot @ 1.5 turn a.s., 240/512 p.v.

zorba75482
Posts: 112
Joined: Tue Mar 12, 2013 11:50 pm
Location: Texas

Re: Jetting question RZ350

#160 Post by zorba75482 » Tue Jun 27, 2017 12:52 pm

Carbs cleaned a few times but just ultrasonic cleaned them but not fitted yet. Last time I had the issue I hit the kill switch and plugs were dry and a little light in color.
One thing I discovered while cleaning carbs this time, is that I had measured the float height from the raised ridge on the face instead of the gasket sealing surface, so was about 1.5 mm too low on float height. Guess this cut the fuel off too soon but not convinced it will make that much difference as the bike takes too long to recover after it dies
Steve

RZ350 1984 project D&Gs, Y Boot
Laverda 750 SF2 1974
BMW R90S 1974
Ducati GT1000 2009

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pushstartrearset
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Re: Jetting question RZ350

#161 Post by pushstartrearset » Tue Jun 27, 2017 1:14 pm

if the needle jet is clogged, all the fuel won't make it's way that blockage will keep the fuel from flowing....on the flipside, if the main is too rich, then it will misfire / four stroke and you won't have a chance to make top end, possibly only when it is cold for a short time, but then it will soon burble out like a mad dog.. I wish someone on here had solid main jet advice for DG's and the Y-boot...speak up!!! Sometimes bike problems can be stubborn. Don't neglect that passage way I talked about. The previous owner that sold us our 84, gave up and sold us an RZ w/ 3k ORIGINAL miles for 1500 only a few years ago. <---how often do you find a deal like that...score of a lifetime....but i put in many a night trying to figure wtf was going on...had to look real close to see the details.

Problem w/ old repairable stuff is sometimes you really have to burn the midnight oil (bust yer as, bloody knuckles, swear like a drunken sailor). I fixed that puppy after 1 year of fiddling (dimwit, i know and slow), but the bike ripped like a mother*ucker after that blob removale, change to toomeys (keep the K&N Ypboot as the dynojet needles are jetted to that).
1984 RZ350L (U.S.) Old Toomeys, oil injected!, Y-boot K&N. loctite throttle cable holder on left carb!! , 410 mains, Dynojet needles 2.0 clip, #20 pilot @ 1.5 turn a.s., 240/512 p.v.

hondaror
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Re: Jetting question RZ350

#162 Post by hondaror » Wed Jun 28, 2017 3:44 am

There is no ideal jetting for any set-up for everyone. Depends where you live, for weather, atmospheric conditions, state of your engine, the way you ride, set-up combinations. There are just too many factors.
For making changes, keep it simple. Leave the pilot alone, it's primary function is the idle circuit and it won't make much difference across the board. Mess with the clip position on your needle jet. Move it up one notch to lower the needle. This will lean out the middle half of your throttle. It should feel crisp and throttle in the mid range should be responsive and rev quickly. Try lowering the clip to raise the needle. See what that does. Remember, you want fast response, crisp sound. Once your needle is set, time to tackle the main. Only go up or down by one size at a time. You want a crisp dry sound. This is where plug chops enter the picture. Before you even do a chop, check the plugs after running it and revving it on the new jet. White, you are too lean. Do not attempt a chop. Black and wet, you might as well go down another size. I think you get the idea.
Rory
2 1984 RZ350s
1985 RZ350
9 1986-1990 RZ350s
2000 ST2
2005 749
2005 749 with 999 engine

zorba75482
Posts: 112
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Re: Jetting question RZ350

#163 Post by zorba75482 » Fri Jun 30, 2017 12:21 pm

Will fit carbs and try later. Also want to replace pick up wires as they are hard and brittle at the ends
Steve

RZ350 1984 project D&Gs, Y Boot
Laverda 750 SF2 1974
BMW R90S 1974
Ducati GT1000 2009

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