1987 RZ350 mis-fire on right cylinder.

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MK
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Re: 1987 RZ350 mis-fire on right cylinder.

#16 Post by MK » Sun Mar 11, 2018 4:11 pm

Lots of clairvoyants these days.
And the usual "Don't have a clue so it must be the part I know the least about ... the CDI"
Bye
Martin

99hybrid
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Re: 1987 RZ350 mis-fire on right cylinder.

#17 Post by 99hybrid » Sun Mar 11, 2018 8:08 pm

Clairvoyant signing off.

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Redline Junkie
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Re: 1987 RZ350 mis-fire on right cylinder.

#18 Post by Redline Junkie » Sun Mar 11, 2018 9:07 pm

Ok so I just removed the air box to allow for easy access to the carb, plus I have a set of Uni Filter pods to install once sorted out. I used my new Syncometer1-30 to check the carbs and I had them very with close with the steel wire method under the slides. The next step will be to remove the carbs to check my work, float height, needle and seat, pilots clear, emulsion tubes clean, clear and round.

The right side seems really rich with goo coming out the right pipe or just un-burned fuel, while the left is nice and tan in color and dry at the end of the silencer. I must say that I’m surprised at how much gas is coming out of the intake side of the carbs while blipping the throttle to 4-5k RPM. (Fine atomized mist).

I’m currently running 230 mains on 1UA power jet carbs with 27.5 pilot and needle clip in middle position at sea level. Air screws at 1.75 turns.
1985 RZ350F being restored now!
1987 RZ350 Stock
1985 RZ350F basket case
1985 RZ500 Stock

MK
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Re: 1987 RZ350 mis-fire on right cylinder.

#19 Post by MK » Mon Mar 12, 2018 4:12 am

BTW: If you exchange the left/right plug wires and the issue is still on the right side, then it's 100% no electric issue.
If it changes the side, then change the spark plugs from left to right.
If BR plugs have run rich and fouled, it's a good idea to get a new set.

If it changed sides and it wasn't the plugs, I'll have to prepare a good excuse for anyone feeling offended.
Bye
Martin

99hybrid
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Re: 1987 RZ350 mis-fire on right cylinder.

#20 Post by 99hybrid » Mon Mar 12, 2018 9:12 am

No excuse necessary. My skin is thick.

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Redline Junkie
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Re: 1987 RZ350 mis-fire on right cylinder.

#21 Post by Redline Junkie » Thu Mar 15, 2018 8:24 pm

Update!!!!

Ok I got a bit of time today to dig into the bike. I pulled the stock air box out as my new UNI pods arrived. As I said I had a pair of 31K carbs ready to go but took them apart just to ensure everything was correct and clean. The mains were 270, 22.5 pilots, floats set to 21mm.

So before I pulled the 1UA carbs I removed the right spark plug cap to check for a poor connection or corrosion. The cap and wire look good.

So pulled the left carb first and then the right. As I pulled the right slide out of the carb and took a look at the jet needle and then compared it to the left and bingo, they are not a matched set!! The left carb had a 5K1 and the right 5L20 (thinner/richer). So I decided to continue with the carb swap to be sure and installed the 31k’s. Air screws set at 1.5, jet needle at clip 2nd grove from top.

Give her a few kicks and she fired up, next adjusted cable free play on throttle and used my Snail Syncometer to set the idle. Next used a ratcheting clamp to hold the throttle open at 5k RPM by letting it rest on the brake lever. Used the sync tool and and they we off by a bit so adjusted the cable on the left carb to match the right. I got to tell you it sounded very crisp and responsive and had a real nice idle Bing Bing Bing!!

Although it was only 3 degrees Celcius today I had to take it for a spin and boy does it work nice now, need to do a plug chop when it warms up to see where it stands but it runs really smooth now.

I guess I must have mis-matched the needles last fall, just goes to show double and triple check your work!

Thanks Guy

Rob
Last edited by Redline Junkie on Fri Mar 16, 2018 7:38 am, edited 1 time in total.
1985 RZ350F being restored now!
1987 RZ350 Stock
1985 RZ350F basket case
1985 RZ500 Stock

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JonW
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Re: 1987 RZ350 mis-fire on right cylinder.

#22 Post by JonW » Thu Mar 15, 2018 8:35 pm

Well done Rob, great news!
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Re: 1987 RZ350 mis-fire on right cylinder.

#23 Post by hondaror » Fri Mar 16, 2018 12:33 am

Yes, that's fantastic. Good work.
Rory
2 1984 RZ350s
1985 RZ350
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