Topic: Mo the 80 CB650 Custom: "As the Spanner Turns..."

[Kurlon]

Did it fire back up after sitting for a bit?  What you're describing sounds like fuel starvation.

[manjisann]

No, I didn't get it to fire up even after my lovely walk (damn it's a good thing I've started exersizing or else that wouldn't have been so much fun  ) I checked the fuel filter and it had fuel in it, and I could hear some sloshing in the tank so I'm relatively sure that isn't the case. However, I haven't really done much to verify what it was otherwise so I'm not going to say it definately isn't fuel starvation, just that I don't think it was. It was a bit too late to try figuring it out.

At this point I'm going to try and do some basic plug chopping and see where I go. Like I said, the way it was handling with the duct tape on has me very puzzled, I'd have sworn that it was rich, but after this and what Scunny is saying, maybe I'm completely off. I just wish I knew of a good place around here to do plug chops.

Do you think riding it till it bogs really bad and then killing the engine and pulling the plugs would tell me anything?

Brandon

[Hush]

I'd say it running extremely (read sieze you #$%*) lean, if it was so rich it "bogged" your plugs would be a lovely fluffy black and they wouldn't be firing to happily but you describe a lean condition Brandon.
It may not be the carb fault either, check your fuel delivery hose (listen to Auntie Kit young man!) for kinks or bends.
Also you had to do some major work on your tank so maybe check that tap you did all the work around, you may have melted the inside filter into a blob.
Those strangely shaped tanks are a pure sod to get the crud out of, I drained mine 4 times and was still getting crap out of it, I blame the shape.
Thinking about your problem, the reason rejetting (going bigger) is important after fitting pods is I believe because the pods allow a lot more air in (therefore leaning the mixture) than the stock airbox that allows for a still area for the air to accumulate before being drawn into the carbs.

[manjisann]

No intank filter to melt into a lovely blob of fuel stopage so that's not an issue. I also made a spiffy line T that pretty much gets rid of the hose kinking, instead of a T, it's got the top part 90 degrees toward the petcock (I swear I have a pic somewhere, I'll post it if I haven't already.

I'm beginning to suspect that all of you may be right and I seriously underestimated the effects of the pods on the jetting. I'm going to call around to the local dealerships this week and see if anyone carries the jets I need and has them for cheaper than $6.50 per jet. I'll also attempt to do a plug chop (although I honestly have no idea where I'm going to find a place to do a WOT chop.) I may just get her running again and ride her till she bogs and pull the plugs at that point and see what it tells me.

Ahh the joys of customizing stuff 

Brandon

[The_Crippler]

I hear you there.  I've also wondered what the heck to do when I have no idea where to do a WOT plugchop.

[Kurlon]

If you pull the plugs while it's bogging, the reading won't be any good.  You need to pull'em BEFORE it starts acting up.  I agree with the others, I think you're lean.  The bike started getting warm, so you richened it up by taping over the filters.  That plus the time it sat while you did so allowed it to cool a touch, and with the richer mixture being closer to right it ran longer... but still being lean it got hot enough to get pissy.  The white plug electrode/strap points to the lean theory.  If you're seeing fluffy/dirty plugs normally after bogging thats because you're already at a point where it's misfiring, wrecking plug reading accuracy.

The next time it acts up, make sure you have a spare plug in your pocket.  Check to see if you have spark on each of the leads.  Also carry a screwdriver long enough to open each of the bowl drains, turn the gas off and open each drain.  It should piss itself out of each carb for a bit if the bowls are full.  Having working carb drain hoses in place are handy for this test. : )  (I don't bother, but I do carry a clear hose I can put in place to test each carb as needed.)

On jets, call Sudco, they sell jets in packs of 4, and I wanna say they are only $4 a pack?

[manjisann]

Ok, so good news. I found a local shop that carries Keihin mains, actual name brand Keihins with the K and star stamped on them, and they were only $3.95 a piece    Having realized the error of my thinking (courtesy of Kurlon and everyone else pounding it into my backward thinking mind, I went and picked up some 120 mains. I also picked up a spiffy jet driver by motion pro, this way I won't bugger the jets.

Before picking up the jets I had started the bike after confirming there was fuel in the tank. She fired right up.

I got home, dropped the bowls, and installed the bigger jets. Started her up and off I rode. I noticed a huge difference right off even with her not completely warmed up. She wasn't as responsive on the top end, however she would still pull a lot higher revs even once warmed. Once she warmed up she still burbled a little when the throttle was opened a lot but she would slowly pull up the rpms. She still isn't responding how I would like her to, but with the 120's in there is an enormous improvement over how she has been performing. I've decided to let her rest tonight and not press my luck (basically it's getting late and will start getting dark soon.) In the next couple days or so I'll drop the needles down to richen her up and see how she reacts before getting bigger jets. I think I'm getting a lot closer though. At some point I may do a plug chop. I just really don't know where to do one around here, and I'm sorta lazy. With it improving like this I'm pleased. Thanks everyone for helping to set me straight!

Brandon

[Zaipai]

Thats great Brandon I love it when there is progress don't you? Now just to hone her in and you will be all set.

.: Scott :.

[Hush]

You mean you are gonna drop the wee clips on the needles down don't you!
Thus RAISING the needle..............

[manjisann]

Some progress on the bike today... well sorta. I pulled the carbs off and dropped the clips down to the lowest setting so the mixture is richer now. I also fixed the threads on one of the vacuum testing plugs (where you hook up the carbs sync gauge), it was a little buggered so I ran a tap through it and cleaned them up. I also set the pickups back to normal settings so it shouldn't be retarded or advanced anymore.

I also lubed the cables and routed them differently, which apparently was a mistake as the carbs will no longer return on their own. Since everything was already off I checked and adjusted the valves again, they were really close, only maybe off by .001 either direction, so a promising sign.

I started her up and she was making an odd noise. I determined that cylinder 2 wasn't firing by touching the pipes, all others quite toasty, cylinder 2 was barely warm. I pulled the plug and checked it, also checked it for spark by holding it against the engine, plenty of spark it seemed, so that wasn't it. I cracked the float drain screw and fuel came out of there, so it's at least getting fuel to the bowls. I ran out of time so I put everything back. I'm thinking I'll have to go into the carbs again, kinda a bummer but no biggie since it will give me an opportunity to redo the cable routing and get it corrected. After checking all of the above I did start her again and revved it to 5k and abruptly killed it and pulled the plug. The plug seemed dry, so I'm thinking somehow no fuel to the cylinder.

Brandon

[Hush]

Your cable routing may have left one carb slide not working Brandon, check that first.

[manjisann]

I pulled the carbs and checked the suction on all the cylinders by placing my hand on the intake side, and they all had plenty of vaccum. I checked the carbs and everything was good. I pulled the plugs and cleaned them, checked gapping, and checked that all of them sparked, everything good there. I also set the pickups back to stock and reset the gap on them, it was pretty open. Rerouted the control cables, mounted the carbs and fired her up... #2 still was only just luke warm while all the others were VERY toasty.... GRRRRRR

Since I was pretty sure that the carbs were flowing properly and everything was sparking I decided to do a carb sync to see if Hush was right. I had bench synced them before so it seemed odd that the carbs would be so off that it would prevent any of the cylinders from firing, but that's what it turned out to be. I synced them all up and locked everything in, and she runs better AND cylinder 2 was toasty!! I also set the airscrews to only 1/2 turn out from seated, since the plugs were still looking really lean. I took the bike for a ride and with the 120's and the clip all the way to the bottom so the needles were raised as much as possible, she ran pretty well and was pretty responsive, but after a while she began to bog down again, but it was still more responsive than before. I also suspect my idle circuit is lean, so I may be upping the idle jet as well. I'm just trying to decide how much I need to go up on the main jet size.

Brandon

[manjisann]

I purchased some 125 mains, put them in and went for a ride, She felt super responsive and everything was going well. I went to get onto a road that has a speed limit of 40 mph and suddenly the bike started to bog really badly.Even though she was bogging she was still willing to accellerate, albeit slowly. I got the bike home and pulled the plugs. I wasn't too surprised to see the 1-4 plugs looked super lean, but when I pulled the inner two they looked very dark, almost rich.

I touched the pipes and the outer two were VERY warm but 2-3 were not. I tried to get 2-3 to spark but they wouldn't, I thought it was because I had them both out, but even after putting number 3 back in I couldn't get #2 to spark. I put the plug into the #1 line and it sparked very well. I'm really beginning to suspect some sort of electrical issue, like maybe the coil or something is causing the 2-3 cylinders to only spark some of the time which would make those plugs look rich. It only seems to happen after I've been riding for 5-10 minutes, putting the bike through its paces.

I think I'll start swapping parts and see if the issue follows the swap or what. In some ways I'm hoping it's just a coil, cause I'm getting very discouraged. I just have a hard time believing that the carbs being non stock with pods could be causing THIS many problems.

I also don't understand why the plugs are showing the deposits they are unless there is something other than A/F mixture wrong. The pods are 2 into 1's so there shouldn't be an airflow issue like individual pods. I have no real problem believing that I was running lean, but at this point I am having a seriously hard time believing that the inner two cylinders are running near correct while the outer two are showing so lean. I'd almost think the outer two cylinders weren't firing if it wasn't for the fact that the exhaust pipes are scalding hot.

I did check that there is fuel in the 2-3 bowls by cracking the drain screws and gas dribbled out (I didn't open them a ton, just enough to leak.)

Here's pics of the plugs, 1 is first.

Any thoughts?

Thanks

Brandon

[Kurlon]

Swap the coils, see if the problem follows the coil (would make sense, coil warms up and thats when it craps out) and causes 1 and 4 to fail out.  If it doesn't, points?

[Hush]

It's a 650, they don't have points!
But yep I'd be suspecting a coil fault too as #1 and #4 run off the same coil and #2 and #3 run off the other coil.
It might not be a duff coil, could be just some loose wiring around the coil.
The way your bike behaved I'd say it was only running on 2 cylinders when you rode it today Brandon, these bikes will run happily on 1 cylinder...no #$%* I've done it when I accidentally fired up the bike with 3 plugs out and only one connected.
The "bogging" would be excess gas being delivered to plugs that weren't firing at all.

[Zaipai]

It's a 650, they don't have points!
But yep I'd be suspecting a coil fault too as #1 and #4 run off the same coil and #2 and #3 run off the other coil.
It might not be a duff coil, could be just some loose wiring around the coil.
The way your bike behaved I'd say it was only running on 2 cylinders when you rode it today Brandon, these bikes will run happily on 1 cylinder...no #$%* I've done it when I accidentally fired up the bike with 3 plugs out and only one connected.
The "bogging" would be excess gas being delivered to plugs that weren't firing at all.

Yes I was thinking the same thing. New coils may not be very cheap but worth the money. Do check the wiring first however. I have seen this before with just mixed up wiring, where one was just shorting out enough to cause problems..

.: Scott :.

[manjisann]

Thanks for weighing in guys    I don't think it's a short, at least not from the coils to the plugs, however, it's cheaper to check and be wrong than to not check, buy new parts and find out that it was a short. Sadly I probably won't have time to check this until Monday, assuming the weather holds. Guess I'll just relax and try and find a zen state and just let all the frustration melt away. I'm going to get this going and running, I just wish it wouldn't cost so much 

Brandon

[traveler]

I'm betting someone may have some good used coils that you could get and save a few coin......no sense buying brand new when quality used will suffice.

I too thinkt hat is the problem.  125 mains......yeah, you have plenty of jet......timing has been checked......the plugs are good....no cracks, right?

You could use an ohmmeter and troubleshoot the 1-4 coil, or as stated earlier, swap coil and check.

again, my bet......swap out the bad coil, and you'll be happy riding....in fact, you may have to change that main jet....125 is HUGE for a stock 650.

~Joe

[manjisann]

Traveler, Plugs are pretty new, I put them in so they have less than a few hundred miles on them. I replaced the wires and caps a month or so ago. So from the coils forward I'm pretty sure it's good. What has me puzzled is why the outer two cylinder plugs are so lean looking while the inside ones were fouled. When the two middle ones cut out would it cause the outer two to burn hotter due to having to work harder?? We'll see what swapping the wires finds out.

The only issue with checking the coil with an ohm meter is the bike seems to run fine until it's had a chance to really warm up, so with the coil cold it would in theory at least, check out fine.

In many ways I'm really hoping that the coil turns out to be it, otherwise I'm back to square one.

Brandon

[traveler]

Have the carbs been sync'ed?

The plugs that are fouled......are you getting spark?

~Joe

[manjisann]

I had synced the carbs just the day before. When I saw the fouled plugs I started suspecting that the plugs were the reason it wasn't firing, but when I put the fouled plug in the #1 wire it sparked just fine, however, when I put one of the clean plugs in the center cylinder wire it wouldn't fire.

I couldn't help it, I got home and fired the bike up just to see what happened. She fired right up and all 4 pipes were toasty, I only idled it for a few minutes. This doesn't really confirm my suspicions about the coil acting up once it's hot, however it doesn't prove it wrong.

Once I get the coil issue figured out I'm going to try running the pods with some tape on them again. I'm suspecting that when moving the outer carbs are getting significantly more air than the inner two and is one of the reasons for the plugs looking so different. I'm just going to leave a small portion of the tops open and most of the bottom (somewhat like the way the old 750 airboxes had their air intake on the bottom, I know it's not the same, but..). Anyhow, I'm hoping that will help to even out the air to the carbs. It would also have the added benefit of reducing problems with rain and side winds.

Brandon

[manjisann]

OHHHH and on the bright side of things, I scored a speedo on eBay for $29.99 including shipping, and it looks to be in excellent physical condition, so I'm really hoping it will fix my buggered speedo issue!

Brandon

[Frankenkit]

omg. this was the one, wasn't it?

[Kurlon]

The reason the plugs are reading differently is you're pulling them AFTER the trouble has started.  If the inners aren't firing, they'll turn dark REAL fast.

[manjisann]

HAHAHAHAH of course, and it matches the paint, what are the odds 

Kurlon, you have mentioned that I need to pull the plugs before it starts to bog, but since it's not really predictable, would pulling the plugs right after it starts to bog down tell me anything useful? Or should I just ride it around for like 10 minutes or so and pull the plugs and just see how they look?

I may go ahead and do the tape test and possibly make the side covers anyhow. Is it really likely that I need larger jets than 125's? That is just enormous for my stock motor. Cutting down the air would help I think. I know that I can't really hope to emulate the stock airbox performance, but well, a little more restriction couldn't be bad. But one thing at a time, gotta get the firing issue sorted out first.

Brandon