2 dead cylinders?

[M_Hills]

Here is my update.... I can not get #2 to run.... 1,3,&4, are running. I pulled the #2 plug and it has good spark (i picked up the appropriate socket ) I also rented a compression checker (i am sure that is the technical name for it) but it does not have a small enough fitting to go into the plug hole . FREAK, one hiccup after another!!!

I do have gas in all of my float bowls and they can drain continuously so I think that means my fuel flow is good? How do I know if the #2 carb is getting gas from the bowl to the cylinder?

I tried the small bursts of starter fluid and the bike did sound different (smoother) but i can not really tell if that is the #2 picking up or if it is just the different type of fuel burning differently. Any ideas?

One more ? ..... If I charge my battery the bike turns over nicely..... I can even let it set for a couple of days and it still has a nice charge on it. This all changed when I was working on it, letting it run as i screwed around with the #2 plug, wire, etc. (and I rode it around the block a couple of times to see if that would do anything (wishful thinking, I know))..... When I got it back to the garage and shut it off, the battery was dead and needed a jump to get it started again. If this was my car I would guess that it has an alternator problem too. Does that sound probable, or do I just have a bad battery?

Well, thanks again for all of the help on this!!! I going off the grid for a week and a half as of Monday night. (I am going to my property in the bush!!! No cell, no internet, no power, no problems ) So, don't think that I gave up on my bike.... Just taking a break from life!!!

[M_Hills]

BTW Volker... I did have a fuel issue too. My gas line had a kink in it and was restricting flow. At least one thing so far has had an easy remedy ....

[Folsoml]

One more ? ..... If I charge my battery the bike turns over nicely..... I can even let it set for a couple of days and it still has a nice charge on it. This all changed when I was working on it, letting it run as i screwed around with the #2 plug, wire, etc. (and I rode it around the block a couple of times to see if that would do anything (wishful thinking, I know))..... When I got it back to the garage and shut it off, the battery was dead and needed a jump to get it started again. If this was my car I would guess that it has an alternator problem too. Does that sound probable, or do I just have a bad battery?

You are having the problem I just encountered. I would fully charge the battery and could ride around until the battery died. The bike was not charging the battery. Turns out my rotor was bad. Rotor should test 4.5 to 5 ohms across the slip rings (don't believe your Clymer Manual!!). I had mine rebuilt and it fixed the problem. Check out this thread for a discussion on the topic:

http://www.hondacb650.com/viewtopic.php?f=4&t=6508

Also, a bad rotor can also short out your regulator/rectifier.

[Volker_P]

Now my 1,2,&4 cylinders are firing and my #3 is not....

So obviously #2 did fire some time ago.
You may try to swap ignition components between 1+4 and 2+3 circuit, possibly something is too weak to fire both plugs at compression, too.

Insufficient charging may also cause weak ignition, so start there. I you are lucky, it just runs on all four then, if not still time to care for #2.

Check out if the headlight gets brighter when you rev up and measure charging voltage.
Possibly this is related to your work so verify all cables and contacts are clean and in place.

[M_Hills]

I'm back!!! Now after a week of meditation...... I have no more clarity than I did when I left!!!!

My headlight does get brighter with higher rpm. (what does that mean?)

I would like to test my charging system today and post my results. (how do I do that?)

I am going to track down a compression gauge today that fits my plug hole too. (do i check my compression with the bike running or just turing over?)

Also, I am assuming that I was screwed up when I thought that #2 was running. With what I have learned along the way, I don't believe that I was qualified to make that judgment at that point in time

[M_Hills]

So, here is the new news.... I have compression! Yay

I do believe that I have good spark on all cylinders so I just jumped on in and ripped the carb out. Not knowing what to do, I just pulled the float bowls off and started spraying carb cleaner in all the different orifices. (including my eye ) With this extremely technical approach, I was not all that confident. However, I think that I may have found my problem (or at least part of it).... On #2 carb, when I spray carb cleaner into the jet orifice nothing comes through the ports. All of my other carbs shoot carb cleaner through the 4 little port holes freely when I do this. I believe that this is how the gas is supposed to go through the carb and into the cylinder right?

This is the pressed in jet that I am referring to. I guess that this is the "slow jet"? What is the difference between jets?

Also, how the freak am I supposed to un-clog these nearly microscopic holes????

Another idea that I have is to replace that carb with a #2 carb off of my back-up carb.... I don't know which will be the easiest path forward

[cgswss10]

What about just replacing the JET that is clogged from your back up (assuming it is not clogged)

Your in the area we all get ot when cleaning carbs. and there are a lot of way that the collective "we" got them un clogged. The Good news is that you can get them out. Those with'81 carbs (like me) are not near so lucky.

Long soaks in things like pure Pine sol and Simple green are top on the list. I soaked my carb bodies for 3 day and blew the ports out on a regular basis with carb cleaner and an air compressor before they "came clean" Many have good results using a .012" guitar string poking thru the hole. By far the best results come from dropping the stuff in a ultrasonic cleaner. I happen to pick a small one up at a yard sale for $3, you can get new ones from Harbor Freight for around $30

I "sharpen" the tip of the little straw on the carb cleaner so I can force the tip into the tiny ports when spraying.

I'm guessing you haven't seen this. it doesn't exactly shoe your carbs, but it shows a lat of info that you should have

http://www.cb750c.com/publicdocs/SeanG/Honda_Carb_Manual_revD.pdf

[M_Hills]

I have an 81 myself... What does that mean for me?

[cgswss10]

The '81 carbs have press in jets, but they are berried inside the the tubes so you can't get them out (with out modifying them) This means that most that have the 44A carbs strip the whole carb and soak the whole boy to get the low speed jet clean. Takes a lot bigger Ultrasonic cleaner too.

N ow there is a way to get them out. You need a 4-40 tap, a 4-40 screw, nut, and a couple of washers. Basically you tap the jet (before it goes down to the tiny hole). Then you screw in the 4-4-0 screw with a couple of washers and a nut on the shaft. once you bottom out the 4-40 screw, you turn the nut to pull the jet out. There is the theory that the screw threads in front of the opening will effect the flow. I did this on my spare carb bodies and my original 44A carbs and frankly they ran just fine. I happened into a deal on some 44C carbs (from the '82) which have screw in low speed jets, and those are now on my bike. (I have a perfectly good set of 44A carbs sitting around waiting for me to do something with them.)

I think there are a LOT of people driving around with '81s that have at least one low speed jet clogged and compensate by bumping up the idle speed

[M_Hills]

I got them all running!!!
Thanks to the guitar string and a can of carb cleaner in my slow jet I'm totally pumped!!!

I have a long way to go on this thing though.... I still have a charging problem, I now have a fuel leak out of my # 2 float bowl , and my eye still hurts from the carb cleaner last night
The motor also leaks oil out of every seal and gasket possible!!! I want to synch my carbs and check my timing... I also feel like I should check over my valve positioning.

I need to do my fork seals, my master cylinder reservoir, and rear tire.

I pretty much know how to deal with most of these things, just parts, time, and effort.

My biggest problem at this point is that just have so much to do on this thing, I do not even know where to go from here.....

I don't know what to do as I have more things come up. Should I start a new thread, or just keep this one going?

Thanks for all the help on this guys!!!

Does anyone have any advise on how to approach a project like this?

[cgswss10]

I would start with the carb leak. You may be able to fix this by just removing the float bowl.

To make the bike rideable, you next step is the charging issue. Most of the time this boils down to the Rotor. There are two slip rings on the end of the rotor. clean them up a take an ohm reading across the two bands. The reading should be very low. I get 5 ohms on mine which I think is about normal. If you get an open (infinity reading) start looking for a rotor, or have your rebuild. Next check each slip ring to the center core. In this case you WANT an infinity reading. If this is not an open, you need a new rotor or to have yours rebuild. If you want to rebuild check out this site

http://www.tpe-usa.com/

[onepieceatatime]

I would start with the carb leak. You may be able to fix this by just removing the float bowl.

To make the bike rideable, you next step is the charging issue. Most of the time this boils down to the Rotor. There are two slip rings on the end of the rotor. clean them up a take an ohm reading across the two bands. The reading should be very low. I get 5 ohms on mine which I think is about normal. If you get an open (infinity reading) start looking for a rotor, or have your rebuild. Next check each slip ring to the center core. In this case you WANT an infinity reading. If this is not an open, you need a new rotor or to have yours rebuild. If you want to rebuild check out this site

http://www.tpe-usa.com/

+1 on this.

The rotor should measure between 4 and 10 ohms ring to ring. Remember to subtract the value your meter reads with the leads shorted together. If the rotor is bad, it often takes out the rectifier regulator also.

[hondamark]

a welding tip cleaner works great for cleaning carb jets!

[M_Hills]

So, I fixed my carb leak. Now there will be no epic explosions like in the movies!!!

I need to get one of those" ohmometers" (another technical term by me ) to check over my rotor..... I am sure that something is screwed here.

I have probably seen 50 warnings that bad rotors can cause the rectifier to fail too. How do I test the condition of my rectifier to know if i need to replace it?

After I get my charging system working properly, I will move into the realm of smoothing out the kinks in how she runs..... I am sure that I will need tons of direction in that arena.

[onepieceatatime]

I have probably seen 50 warnings that bad rotors can cause the rectifier to fail too. How do I test the condition of my rectifier to know if i need to replace it?

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