Need help....weird engine issue

General forum on engines, transmissions, gearing and modifications to each

Moderator: rztom

Post Reply
Message
Author
User avatar
RZed
Posts: 307
Joined: Fri Dec 04, 2009 12:32 am
Location: Oregon City, Oregon

Need help....weird engine issue

#1 Post by RZed » Sat Sep 23, 2017 4:30 pm

So, I was on a ride with my buddies last weekend and all was going well for the first 60 miles. The bike was running great as usual. We stopped for a lunch break, and went to leave....that's when the trouble started. I kicked it over and it was idling, but when I gave it some throttle it died. Tried it again, same thing. I could get it to idle and then crack the throttle and it would run in the upper RPM's (above 4000). But would die below that.
I was able to limp it over to my friends house where I pulled the carbs thinking it was some bad gas. (Had the same thing happen about a year ago and it was from bad gas. Slime in the float bowl from Ethanol gas.) Carbs looked clean, put it back together, and limped it home.
I've since pulled the carbs again and totally disassembled them checking for anything suspicious. Found nothing, cleaned all the jets and body passages, then reinstalled on the bike.
Today I tried to start it and it would fire on the first kick, but would not stay running. Same thing every time. I pulled the plugs to see if I had good spark and it looked good when kicking it over. I checked my electrical connections to see if I had a bad wire or something but everything looked to be ok.
I'm still running the original stator/CDI, maybe it's going bad. So I'm at a loss as to what it could be. Any ideas on what it might be or what I should be looking at would be greatly appreciated. :smt023

Thanks in advance,

Charlie
1985 RZ 421 Hybrid viewtopic.php?t=9655
99 R1 USD front end
Tarrozi Hi-rise clipons
TrailTech Endurance II Speedo/Odometer
VJ23 swingarm
CBR F4i rear shock/custom dogbones
JL GP stainless pipes
2018 XSR 900

seahorse
-----
-----
Posts: 1352
Joined: Sun Sep 11, 2011 7:25 pm
Location: Perth Western Australia

Re: Need help....weird engine issue

#2 Post by seahorse » Sat Sep 23, 2017 7:16 pm

Reading your blurb I would have came to the same conclusions.
Double, triple check your pilot jets. Blow them out with air or aerosol CRC lube or something like that. You need to see that they are not blocked. It does not take much to block them. Are you running an inline fuel filter, if not I would suggest it.

Check all wiring connectors, particularly stator connectors under seat near battery box.

If that fails, and you can get your hands on a replacement CDI to try, then give that a go.

I still think, like you, that it is fuel/pilots.
Good luck
81 RD 250 LC Hybrid .Widened frame with Aprilia RS250 Back end & Front end, strokd RZ 421, Kennys TSA's, 31KVM26SS Carbs M-360 P-25 ALBA Ndl Pos 3, Air 1.3/4
81Rd350lc resto 2016
81 Rd250lc resto 2017
1999 ZRX 1100

User avatar
RZed
Posts: 307
Joined: Fri Dec 04, 2009 12:32 am
Location: Oregon City, Oregon

Re: Need help....weird engine issue

#3 Post by RZed » Sat Sep 23, 2017 7:39 pm

Thanks Seahorse!!
I'll pull the carbs and check the pilots again. I had used a small tip cleaner from a Oxy/Act torch set that I used to make sure they weren't plugged. Seemed clear, but I'll check again. And I'll recheck everything that you suggested. I think I can get hold of a buddies CDI if needed too.
Any recommendations for good fuel filters? I'm running a Pingel Hi-flo petcock with duel outlets so I'll need to 2.

Thanks again,

Charlie
1985 RZ 421 Hybrid viewtopic.php?t=9655
99 R1 USD front end
Tarrozi Hi-rise clipons
TrailTech Endurance II Speedo/Odometer
VJ23 swingarm
CBR F4i rear shock/custom dogbones
JL GP stainless pipes
2018 XSR 900

JackB
Posts: 182
Joined: Thu Sep 15, 2011 9:06 pm
Location: Chicago Il.

Re: Need help....weird engine issue

#4 Post by JackB » Sat Sep 23, 2017 11:09 pm

I had something identical to that once and it was the spark plugs fouled out. They looked fine-werent all oilyand nasty looking.I had a new set with me so I changed them and it fixed it. Its something simple to try.
1984 Rz350, Wicked Toomey rep pipes, Dynojet kit,Zeel unit,Toomey Y boot filter.

User avatar
RZed
Posts: 307
Joined: Fri Dec 04, 2009 12:32 am
Location: Oregon City, Oregon

Re: Need help....weird engine issue

#5 Post by RZed » Sun Sep 24, 2017 1:37 am

JackB wrote:I had something identical to that once and it was the spark plugs fouled out. They looked fine-werent all oilyand nasty looking.I had a new set with me so I changed them and it fixed it. Its something simple to try.
I had just put in a new set of plugs before the ride and they looked ok when I checked them afterwards, but I'll try a new set just to make sure.

Charlie
1985 RZ 421 Hybrid viewtopic.php?t=9655
99 R1 USD front end
Tarrozi Hi-rise clipons
TrailTech Endurance II Speedo/Odometer
VJ23 swingarm
CBR F4i rear shock/custom dogbones
JL GP stainless pipes
2018 XSR 900

hondaror
Posts: 2828
Joined: Mon Mar 03, 2014 8:44 pm
Location: Alberta, Canada

Re: Need help....weird engine issue

#6 Post by hondaror » Sun Sep 24, 2017 2:21 am

JackB wrote:I had something identical to that once and it was the spark plugs fouled out. They looked fine-werent all oilyand nasty looking.I had a new set with me so I changed them and it fixed it. Its something simple to try.
I recently went through this as well. My issue is fat pilot jets, since setting up on the dyno.the pilots may not be plugged. Could be too rice depending on your set up.
Rory
2 1984 RZ350s
1985 RZ350
9 1986-1990 RZ350s
2000 ST2
2005 749
2005 749 with 999 engine

Post Reply