CL360 Cafe Carb Stumble

[Sonreir]

Possible that you have something still draining the battery. Anytime you mess with the red wires, you're modifying the direct connections to the battery. Red wires carry current even when the key is turned off, so if there's something drawing on them, it will drain the battery.

Might be worth checking the fuses over, too.

 

[Ply318ci]

Checked the fuses they are all good. Charged the battery over night so it is good. Going to check spark when I get home from work and go from there. Also going to re-check timing just incase.

 

[Ply318ci]

Ok so by a miracle I got it running last night. Checked the timing it is good, the left cylinder gap on the points was out of spec (over .016 gap) so I tightened it up to .012-.013 the right points gap was at .012-.013 the whole time.

I pulled the spark plugs and cranked the engine over and I have great spark, the right spark plug was black and wet, so I know it is getting gas. I tried a trick I saw on Top Gear (probably not the best place to get advice but it worked) and I used a lighter to burn off the excess gas and liquid on the plug. The right cylinder was a light brown. I reinstalled everything and it fired right up. So I began tuning the pilot screw.

The pilot screw on the left carb I had to turn out a full 3.25 turns to before it stopped climbing in RPMs. I turned the idle down to around 1200 and did the right carb, no matter how much I turned it the RPM never changed, got all the way to 4.5 turns out and nothing. I know this has been posted here before so I will start digging gopher style but if anyone as any suggestions I am all ears, thanks.

 

[Sonreir]

If the fuel screws aren't doing anything, it usually means your timing is retarded. It might be time to use a timing light and see how close or far you are?

 

[Ply318ci]

Ok I will see if I can get one, thanks.

 

[Ply318ci]

Ok so I took it for a short ride today and it would bog and sputter and run poorly until about 5,000 rpm and then it would run great straight up to redline. I was looking at the intake boots and noticed that they are cracked all over. I am going to order new boots here soon to see if that changed things. It looks like the left boot has been "sealed" with some red colored silicon as a bodge job and the right one was just left along, might explain why the right pilot screw didn't change the rpm when I was tuning it, just to much of a vacuum leak.

Does that sound like a possible issue, it still doesn't explain why the bike ran great a few weeks ago, unless getting warm causes the intake boots to expand and seal up the cracks(?) or why it runs bad until about 5000 rpm and then revs clean after that.

 

[Ply318ci]

Ok so I decided to mess around with my bike more and pulled the plugs to see the color. They are both brown (as you can see in the picture this is after a 5-6 mile ride) I am not sure if they are a good color or not, it looks ok to me considering the left one was black last time I pulled them. Are these good looking, the bike has the UNI pod filters and straight exhaust. I gaped them at .030 inches, they were at .035.

Also I got some carb cleaner and sprayed the intake boots while the bike was running and there was not noticeable difference in rpm, so I figure there are no vacuum leaks even though the intake boots have cracks in them.

Now the major problem, when I kick the bike over it starts no problem, I let it warm up and then tried to tune the pilot screws, I started them at 2 full turns out and went from there. The left screw peaked in rpm at 3 turns out, but the right one peaked in rpms at 1.5 turns out. Any advice at all would be appreciated, I am going to remove the cabs and bench sync them and clean them and set the floats again, is there anything else I should be looking for. The jetting is stock as far as I know for a 1975 CL360 so I am going to get some more jets and spark plugs.

The left plug is the first pic, the right plug is the second pic.

 

[Sonreir]

I usually like to see less than one turn difference between the screws. Have you only bench synced the carbs or do you have some vacuum gauges you can use?

 

[Ply318ci]

I do not have vacuum gauges as of right now, so I am going to take the carbs off this weekend and do a complete clean/bench sync/float adjustment/new bigger jets on them. Do the plugs look ok?

 

[Sonreir]

It's hard to tell mixture without a dedicated chop, but just for running around town they look OK.

 

[Ply318ci]

Ok cool. One more thing, when I first started the bike it had a little bit of white smoke coming out of the exhaust, not a lot just a little. After it got warm it went away. It didn't smell like burning oil just like normal exhaust so I am pretty sure it isn't a oil leak. It was cold in the garage I was working on so could it just be condensation from a cold start up and the normal waste products of combustion?

 

[Sonreir]

Exactly. Just water vapor.

If it were oil, it would usually get worse as the bike warms up, and the smell of burning oil is unmistakable.

 

[Ply318ci]

Got it, I was pretty sure it wasn't oil, I had an old car that would burn oil and this smelled nothing like that. Thanks.

 

[trek97]

Ok so I took it for a short ride today and it would bog and sputter and run poorly until about 5,000 rpm and then it would run great straight up to redline.

I would make sure everything else is correct before messing w the carbs. Like Sonreir stated" Retarded timing along w everything else can give false plug reads"

With the stock carbs and stock jetting + pods + pipes, 360s MAY TEND to run rich below 5000. then may go leaner as RPMs increase above 7000 +.

Thats the reason it runs poorly below 5000 and improves w higher rpm. the "F'ed" up air pressures w the pods (?whatever?) is causing the main primary jet to feed more fuel than needed and the vacuum slides to rise a bit more slowly at low rpms. Below 5000 the engine simply isn't ready to consume the mix its being fed. then once the engine rpm "catches up" the mix its being fed becomes closer to proper.

Hypothetically, its feeding a 6000 rpm mix to a 3000 rpm situation. Once the engine reaches 6000 rpm things come together nicely. then above 7000 rpm, the slides are pert near if not all the way up, however w the stock 110 main secondaries now its getting more air due to the pods, so it may still be feeding the now leaner rpm mix and things might tend to become lean. Due to the leaner mix it begins to burn hotter giving more power...in the event things become too lean for too long it over heats.

Due to the fact that in most "NORMAL" riding situations you're only gonna run her over 8000 + rpm for a few seconds at a time. The fact that its running rich at "cruising" rpm will be the most bothersome.

I have no doubts that both Sonreir and PJ will argue w me about "Normal" riding situations. Spending most of their riding time above 8000 rpms. :

W Pjs carb Voodoo and some jet tweaking of my own my 360 runs good. But this past fall I found my machine is having trouble getting over 85 mph. And w this winter being what it has been. I haven't had any opprotunities to begin troubleshooting the situation.

 

[Ply318ci]

Thanks Trek97. It is funny after I posted my last post I started just cruising the site about jetting and timing and other peoples build threads and saw a post you made describing the effect pods have on jetting and it cleared it up a lot. I also have been reading your blog a lot (I really like your brat style and the twin high pipes) and you have your list of things to check before messing with the carbs, I was going to go through that first because I really don't want to remove the carbs. Then if none of that works I will pull the carbs. I really appreciate the advice and any more you got. Thanks.

 

[Ply318ci]

Ok so I set the point gap again and then did the static timing using a light, it was way off. Turns out my points are at the very end of their useful life cycle, the gap has to be .016 for the timing to stay on. I also gapped the valves to the proper setting. The bike runs a lot better now, still burbles and farts between 3000-5000 rpm, (due to the pods) then clears up fine and then struggles to get past 8000 rpm due to the secondary being the stock jet size and the motor is getting lean.

Now the only problem is the battery won't hold a charge, not sure if it is an electrical issue or a battery issue, the guy I bought it from disconnected the kill switch and the one/off switch on the right handle bar, and the horn and who knows what else, there is about a dozen disconnected wires under the tank. With that said, the lights (hi and low beam) work, the turn signals work, the brake light works, the neutral light works, and the orange turn signal signal in the Tach works. I also always run the bike with the HI beams on to charge the battery, I read on this forum that is how the bike charges.

The questions I have are, I still have the stock air boxes and I was wondering what would happen if I put them back on with new filters (the old ones are full of dirt), and ran the bike like that. Would that solve a lot of the jetting issues, even if I left it with the open exhaust? And now that I changed the timing and valves, and points gap, the right carb pilot screw seems to actually do something. I have set the left side carb to 2.5 turns out as that seems to be the best rpm, and the left one wants to be around 2 turns out, does that sound better? I pulled the screws and both are clean and then I shot some carb cleaner into where the screws went in, should I look for anything else?

Thanks.

 

[rockcitycafe]

If your battery isn't holding a charge, fix that first before even thinking about carbs, otherwise you'll be chasing your tail, low batteries can cause lots of issues that are easily mistaken for carb problems


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[trek97]

Roc City is RIGHT get everything set up correctly before messing w the carbs. And pick up a cheap strobe timing light. you will be surprised how poor even the best static timing can be. amazon or HF sells em pretty cheap.
As long as she's hitting the marks .016 will be fine. I think mine are about .011 to hit the marks dead nuts right now. I have a set of NOS points Im planning to install next time I rip into her....sooner than later. Maybe make a blog post about it.

also, Be careful bubba. The blog can make you go blind.

 

[Ply318ci]

After my battery died on me on a short test ride yesterday leaving me stranded about a half mile from home (lucky me it was downhill the whole way back) I remembered on another build thread you guys talking about the battery and how sensitive the bike is to a bad one. I am going to get a strobe light then first before the points just to make sure my timing is good. I already wasted money once buying a part I didn't need. I got a factory manual I downloaded I will look to see how to check the charging system after I connect all the wires. Also how can I test to see if the battery is bad? It is to small for the auto parts store and they won't test it. Anything else I should be looking for? Thanks.

 

[Ply318ci]

Alright so I messed with it some more over the weekend, followed all your advice and the bike runs great. The electrical problems it turned out was an easy fix, the main fuse for the ignition kept disconnecting from the wire. The previous owner broke the plastic fuse box so the lid won't close all the way and he used electrical tape to fix it, unfortunately that means when the super stiff rear shocks hit a bump and bounce around the wires get jiggled and as a result the main wire going to the main fuse gets disconnected and the bike dies or the wires is barley touching and i get a bad connection. I fixed it by using some more tape. Now i just need to buy a new fuse box and fix it for real. Thanks for the help.

Just curious the bike starts up with one kick hot or cold no choke but for the first few minutes the mid range burble is really bad, like I can't hardly get it to rev past 5000 rpm. Then after a few minutes and it is warm, the bike runs great, just a small mid range burble and then it is clean, any suggestions? Thanks.