[elgaot5]

Hey everyone,

Long time lurker, first time poster. I tend to ramble so I'll try to keep this to the point. I bought an 81 CX500 in November and it was in running order. It's my first bike and I ran out of gas a few times and had to switch to the res to get home. It was running fine until a few weeks ago when I was on a ride and the bike cut out on the freeway after riding for about 30 mins. I had learned my lesson and had a full tank. Pulled over, looked at the bike in confusion, and it started back up. This happened 4 times but I finally got it home. Looked up symptoms on the forum and I'm thinking there might be some crud in the carbs. Last night I finally figured out how to take the seat off (yay me!) and got the tank emptied and off.

I have a pretty long list of things I want to do to the bike and I feel like most of them are within my skill level. I am really just afraid of attempting something that will leave the bike inoperable, but I guess there's only one way to learn. Here's the list of things I've noticed:

-Tank has some rust but doesn't look terrible. I will be rinsing it out as best I can with vinegar and some screws (unless there is caution against vinegar). Also I'm wondering if I NEED to coat the tank after cleaning it. I'm trying to do it without any really harsh chemicals (vinegar then rubbing alcohol to dry it out) but think I've read that you have to neutralize the metal at some point. Is that only for sealants or will I have to prime before adding gas?

-Carbs are the scariest thing for me simply because of the multitude of issues one can face when working on them. I am going to drain the bowls today and see if I get any rust out but I'm thinking about just going for it and attempting a full cleaning. I've seen a bunch of success stories and there doesn't seem to be an issue that hasn't already come up that I could reference, so I might give it a go.

-Forks have no spring to them. If I lift the front end up they move a little but for the most part they are not bouncing like they should. I have no idea how they work so the threads haven't helped me a whole lot. From what I've gathered there are springs... and oil... and air inside?

-Cables: I bought throttle, brake, and clutch cables and these seem like they aren't too difficult to replace but I'm not sure about the fine tuning adjustments.

-Brakes: I want to replace these soon.

-Radiator has half a dragon fly sticking out of it and there is a very small coolant leak coming from an undetermined source. I noticed some smoke coming from underneath the engine block and later found a small puddle of coolant under the bike. I couldnt see where the coolant was coming from but now with the tank off that might be a little easier. I'm not sure what condition the radiator is in but I haven't read up too much on the topic so I'll wait until I'm more informed to ask about it.

Anyhow, that's my current list. Tank should be mostly ready by tomorrow night and I'm hoping the carb drain will help some. I really try to read as much as I can before posting (I've been reading since November!) but I apologize if repeat some questions. I'm really excited to get this thing back up and running, especially with all this San Diego sun! Thanks for all the help you guys have already provided!!

[Ranger]

Check out the quick reference guide in the General Discussion area of the forum.
This is a good link to start with Bike checklist
HTH

Ride Safe

[bandit]

welcome from spain....what a great first post

[Blue Fox]

Welcome to the forum. We will take good care of you here. And don't worry about your skill level right now, start simple and work your way up.

It could be your tank causing your stalling issue. Or a multitude of other things. The very first thing I would do would be to do the main fuse modification. Very simple, very inexpensive to do. Since your bike is a 81, the ignition doesn't depend on the main fuse for getting power. So that probably isn't your stalling issue.

I would suggest visiting the Wiki site. It contains the Quick Reference section of the forum plus many other topics regarding our bikes. Take your time in there, there is much to learn. From carb cleaning to Zerk fitting.

[fibonacci]

Welcome aboard. You've come to the right place and it sounds like you have a pretty good list. There is lots of help to be found here, as you already know.

Fib

[elgaot5]

Vinegar in the tank actually seemed to do a pretty god job of getting that rust out. The tank wasn't in horrible condition but I'm glad I could skip using those crazy chemicals. Rinsed with water, then rubbing alcohol, then some gas. Popped the tank back on but battery had been sitting for too long so I'm trying it today after charging it.

I tend to just get into some things without the proper research (while other things I overdo) and I pulled the brake cable without realizing the line is full of fluid! I have a new brake cable I want to put in so I'm thinking I'll reverse fill it from the bleeder valve and then bleed it a few times with new fluid. Does anyone know what size hose fits on the bleeder nipple?

[anothervenue]

I would just get a new battery. They don't always last that long, and who knows how old that one is or what its been through.

My order goes:

Running
Safety
Mods/Looks

So make it run first (carbs cleaned, tappets adjusted, carbs synced, cooling system flushed/descaled, a pass of clean oil).

If its running pretty well, work on safety (Front end. Brakes, Forks, Steering Bearings, wheel bearings, Tires)

Then do mods and bling it out (Electric fan mod, fork preload spacers, shock)

[TXDrummer]

Welcome aboard! Glad to have you with us!

elgaot5, on 07 March 2012 - 02:32 PM, said:

-Tank has some rust but doesn't look terrible. I will be rinsing it out as best I can with vinegar and some screws (unless there is caution against vinegar). Also I'm wondering if I NEED to coat the tank after cleaning it. I'm trying to do it without any really harsh chemicals (vinegar then rubbing alcohol to dry it out) but think I've read that you have to neutralize the metal at some point. Is that only for sealants or will I have to prime before adding gas?

-Carbs are the scariest thing for me simply because of the multitude of issues one can face when working on them. I am going to drain the bowls today and see if I get any rust out but I'm thinking about just going for it and attempting a full cleaning. I've seen a bunch of success stories and there doesn't seem to be an issue that hasn't already come up that I could reference, so I might give it a go.

-Forks have no spring to them. If I lift the front end up they move a little but for the most part they are not bouncing like they should. I have no idea how they work so the threads haven't helped me a whole lot. From what I've gathered there are springs... and oil... and air inside?

-Cables: I bought throttle, brake, and clutch cables and these seem like they aren't too difficult to replace but I'm not sure about the fine tuning adjustments.

-Brakes: I want to replace these soon.

-Radiator has half a dragon fly sticking out of it and there is a very small coolant leak coming from an undetermined source. I noticed some smoke coming from underneath the engine block and later found a small puddle of coolant under the bike. I couldn't see where the coolant was coming from but now with the tank off that might be a little easier. I'm not sure what condition the radiator is in but I haven't read up too much on the topic so I'll wait until I'm more informed to ask about it.

Fuel tank - IMHO these tanks are three decades old and have had who knows what kind of gunk and crud in them in the past. While it is good to clean it out and get the rust knocked down, you'll continue having problems until you do a proper coating inside the tank. I just finished doing mine, and have more of the sealant coming for other fuel tanks I have on some equipment. I used POR-15 on the bike and will use it for the other stuff. The kit came with water soluble chemicals and as long as you are careful, is isn't a huge deal to coat your tank. I think it cost me $50 for the whole job (including new fuel line and filter). With the methanol in fuels these days, moisture is only going to be harder to control in the tanks and thus there will be more opportunity for rust. Do it right; do it once.

Carbs - Order the carb book from Larry. It will walk you through the whole process step by step and very well done. You can order it right here. Plan on this taking a few days to do properly. It can be a tedious and slow process to do well and do correctly, but the results are very much worth the effort. If you'd rather have him do it, PM him for the details. His screen name is LCRXed.

Forks - Without seeing it first hand, I can't comment on the shape of your bike. Maybe you can get an opinion from someone local and go from there. The forks likely need to have the seals replaced and oil changed. Not hard to do, just pay attention to the details.

Cables - Good plan. Follow the instructions in the service manual for installation. Make sure that they are free in movement once installed, and if not work with them until they are. Ask if you need guidance.

Brakes - If you can't steer or stop, your screwed. Rebuilding the brakes on the bike isn't a hard task. Plenty of info here on rebuilds. Some are replacing their master cylinders and going to dual disk set ups on the front. Myself, I rebuilt the master cylinder and caliper, then replaced the brake line with a stainless braided hose. I'm not racing around and find the brakes more than adequate. I think the parts and all were about $100 or so.

Radiator - You would probably do well to flush it out and get it clean. Drain your coolant and flush the engine as well. As for the leak, there are plenty of places that can leak, you;ll just have to locate the source and make the appropriate fix. Again, this is not a hard task.


Outside of that, go the Wiki site (link in my signature) and find the new owner's checklist, and start through that stuff. You'll spend some time and some money getting things up to par, but you'll also have a very reliable (and easy to work on) bike in the end.


Don't be afraid to do this stuff. All you have to do is ask, and the guys here will chime in and help. Pictures are your friend (ours, too) when it comes time for assistance! In a few weeks, you'll know your bike and won't be afraid to turn a wrench or two on it. That is a lot of the fun, at least for me!

[muzza]

Did you check that the air admission hole in the tank cap was clear? If not the bike will run until the vacuum in the tank overcomes the gravitation weight of the petrol in the fuel line and the petrol stops flowing - which sounds like your symptoms. BTDT.....

[murrayf]

you cleaned the tank but did you clean the petcock and the fuel filter screen in the petcock?

also do you have the vacuum petcock it will have 3 lines going to it vent vacuum to the intake manifold and fuel if so it may be causing your problem

[Thumper]

elgaot5, on 07 March 2012 - 02:32 PM, said:

Hey everyone,

Long time lurker, first time poster. I tend to ramble so I'll try to keep this to the point. I bought an 81 CX500 in November and it was in running order. It's my first bike and I ran out of gas a few times and had to switch to the res to get home. It was running fine until a few weeks ago when I was on a ride and the bike cut out on the freeway after riding for about 30 mins. I had learned my lesson and had a full tank. Pulled over, looked at the bike in confusion, and it started back up. This happened 4 times but I finally got it home. Looked up symptoms on the forum and I'm thinking there might be some crud in the carbs. Last night I finally figured out how to take the seat off (yay me!) and got the tank emptied and off.

I have a pretty long list of things I want to do to the bike and I feel like most of them are within my skill level. I am really just afraid of attempting something that will leave the bike inoperable, but I guess there's only one way to learn. Here's the list of things I've noticed:

-Tank has some rust but doesn't look terrible. I will be rinsing it out as best I can with vinegar and some screws (unless there is caution against vinegar). Also I'm wondering if I NEED to coat the tank after cleaning it. I'm trying to do it without any really harsh chemicals (vinegar then rubbing alcohol to dry it out) but think I've read that you have to neutralize the metal at some point. Is that only for sealants or will I have to prime before adding gas?

-Carbs are the scariest thing for me simply because of the multitude of issues one can face when working on them. I am going to drain the bowls today and see if I get any rust out but I'm thinking about just going for it and attempting a full cleaning. I've seen a bunch of success stories and there doesn't seem to be an issue that hasn't already come up that I could reference, so I might give it a go.

-Forks have no spring to them. If I lift the front end up they move a little but for the most part they are not bouncing like they should. I have no idea how they work so the threads haven't helped me a whole lot. From what I've gathered there are springs... and oil... and air inside?

-Cables: I bought throttle, brake, and clutch cables and these seem like they aren't too difficult to replace but I'm not sure about the fine tuning adjustments.

-Brakes: I want to replace these soon.

-Radiator has half a dragon fly sticking out of it and there is a very small coolant leak coming from an undetermined source. I noticed some smoke coming from underneath the engine block and later found a small puddle of coolant under the bike. I couldnt see where the coolant was coming from but now with the tank off that might be a little easier. I'm not sure what condition the radiator is in but I haven't read up too much on the topic so I'll wait until I'm more informed to ask about it.

Anyhow, that's my current list. Tank should be mostly ready by tomorrow night and I'm hoping the carb drain will help some. I really try to read as much as I can before posting (I've been reading since November!) but I apologize if repeat some questions. I'm really excited to get this thing back up and running, especially with all this San Diego sun! Thanks for all the help you guys have already provided!!

[Thumper]

Last fall got a 1972 Yamaha G7S for $100. with a LOT of surface rust in the gas tank. After trying several things had decent results with a cheap sand blaster from Menards, my 100 psi compressor (with decent enough tank size), and a bucket of cheap play sand that I strained thru a kitchen collander. You can get the nozzle easily enough into the tank and get it blasted pretty good just working your way around. Just be sure to keep your finger off the trigger until the nozzle is completely in the tank, of course. I am skeptical about tank liners and like the simplicity of sand blasting.

[CXPHREAK]

A dirty killswitch will cause your bike to stop running and then restart again after a little while, disconnecting the black/white wire coming from the CDI unit under the seat will isolate this as a cause.

+1 to the suggestion above concerning the fuel cap breather.

[MZM]

elgaot5, on 07 March 2012 - 03:32 PM, said:

Hey everyone,

Long time lurker, first time poster. I tend to ramble so I'll try to keep this to the point. I bought an 81 CX500 in November and it was in running order. It's my first bike and I ran out of gas a few times and had to switch to the res to get home. It was running fine until a few weeks ago when I was on a ride and the bike cut out on the freeway after riding for about 30 mins. I had learned my lesson and had a full tank. Pulled over, looked at the bike in confusion, and it started back up. This happened 4 times but I finally got it home. Looked up symptoms on the forum and I'm thinking there might be some crud in the carbs. Last night I finally figured out how to take the seat off (yay me!) and got the tank emptied and off.

I have a pretty long list of things I want to do to the bike and I feel like most of them are within my skill level. I am really just afraid of attempting something that will leave the bike inoperable, but I guess there's only one way to learn. Here's the list of things I've noticed:

-Tank has some rust but doesn't look terrible. I will be rinsing it out as best I can with vinegar and some screws (unless there is caution against vinegar). Also I'm wondering if I NEED to coat the tank after cleaning it. I'm trying to do it without any really harsh chemicals (vinegar then rubbing alcohol to dry it out) but think I've read that you have to neutralize the metal at some point. Is that only for sealants or will I have to prime before adding gas?

-Carbs are the scariest thing for me simply because of the multitude of issues one can face when working on them. I am going to drain the bowls today and see if I get any rust out but I'm thinking about just going for it and attempting a full cleaning. I've seen a bunch of success stories and there doesn't seem to be an issue that hasn't already come up that I could reference, so I might give it a go.

-Forks have no spring to them. If I lift the front end up they move a little but for the most part they are not bouncing like they should. I have no idea how they work so the threads haven't helped me a whole lot. From what I've gathered there are springs... and oil... and air inside?

-Cables: I bought throttle, brake, and clutch cables and these seem like they aren't too difficult to replace but I'm not sure about the fine tuning adjustments.

-Brakes: I want to replace these soon.

-Radiator has half a dragon fly sticking out of it and there is a very small coolant leak coming from an undetermined source. I noticed some smoke coming from underneath the engine block and later found a small puddle of coolant under the bike. I couldnt see where the coolant was coming from but now with the tank off that might be a little easier. I'm not sure what condition the radiator is in but I haven't read up too much on the topic so I'll wait until I'm more informed to ask about it.

Anyhow, that's my current list. Tank should be mostly ready by tomorrow night and I'm hoping the carb drain will help some. I really try to read as much as I can before posting (I've been reading since November!) but I apologize if repeat some questions. I'm really excited to get this thing back up and running, especially with all this San Diego sun! Thanks for all the help you guys have already provided!!

elgaot5,

Welcome aboard...This forum is top notch... members are very dedicated and knowlegable. I've benefited considerably from participating here - as my situtation is very similar to yours (first bike, etc.). I may have gotten very luck with my first buy (only 4,600mi and the original owner - totally pampered bike).

Do you have a copy of the Honda Factory Service Manual? (see link): http://ftso.net/cx-gl/service_manuals/

Good luck!

[bearman1]

Didn't read anything about an "inline" fuel filter. After your cleaning of the fuel tank, is strongly advised to install an inline filter between the petcock and carbs. This will keep you from having to pull the carbs countless times to reclean 'em.

[elgaot5]

Woah! Thanks for all the suggestions guys!

So last night I went and got an in-line filter and it was slightly bigger than the previous one so I was messing with the lines trying to get it to fit and found there was a piece of something stuck in the line. It might have been a piece of a previous filter but I did my best to wiggle it out but ended up cutting off that last bit and refitting it all. I didn't have enough gas to get the petcock to ON but when I switched it over to RES it filled up nicely. Had a newly recharged battery and after checking that there was gas in the carbs it started right up. It was quieter than normal but I think it's because there's still something wrong with the amount of gas getting in there. More on that in a bit.

I put in a new clutch line and it's a little longer than my original. I ran it the same way the original line was run and it was really stiff. I jumped on another thread and got some lube and that helped a lot but it was still scary stiff. Finally I undid the routing and when the cable was just hanging out it was smooth as silk. I messed with the routing some more and got it to the point where it's pretty nice.
-Question: I noticed that I had a LOT more play with my old cable and it would engage about half way through but now it engages almost when I let the lever go. Is this something I can adjust?

I finally remembered what happened just before I started having issues. My choke cable would not stay engaged in the fully open position. It would bounce back to half open so I would just manually hold it up and let it down slowly. I read that the knob (or base) could be turned to lock the choke cable so I turned the actual knob and it locked up top but it didn't seem quite right. Since then I've been experiencing issues. The bike was warmed up and I closed the choke and the bike was barely running. I would give it gas and the RPMs didn't move up until I was almost fully engaged and then they would shoot up to the expected full throttle. This happened in every gear so it was a little crazy kicking into gear that high every time. As I was approaching home I popped the choke open a bit and the bike sounded a LOT happier but I didn't get a chance to test the shifting.
-Question: I'm wondering if I messed something up with the choke... Could the idle or gas regulation with the throttle have been affected with me twisting or over pulling the choke cable? I must say I am writing this without reading so I'll go ahead and do that next.

Lastly, I think I may have done something right! I read up on brakes a bit and while I was not prepared for a full overhaul I did take the calipers off and checked the pads and they were huge, but I had very little front brake stopping power. I read a few posts on how to bleed lines and decided on reverse filling a new line. I drained original fluid, replaced the cable, and pushed new fluid in from the bleed nipple until the master cylinder filled up. Then I did the manual open-squeeze-close-release bleeding through 3 full cylinders and when I closed everything up I had brakes! (I apologize for the unwarranted celebration. This is a routine procedure but it's exciting for me, haha )

[elgaot5]

Update: I hopped on just now and adjusted the clutch cable and got it to engage much sooner so that's taken care of. Still feels a little sticky though, not as smooth as my old one. Do they wear in over time?

I was able to push the choke in today after giving it a nice up hill ride. There was minimal stuttering and it idled fine. When I give it gas I will hold the throttle at the same position and the bike will rev slowly, then faster, then faster still until it gets to the correct rmp for the amount of gas I'm giving it. The rpms jump and aren't smooth so there is some jerking when getting into 1st and I can't fully engage quickly so it's a slow roll then kinda jumps into full speed. The other gears aren't as bad but there is that initial lack of power. Gonna check up on the forums for these symptoms. I have not done anything to the carbs other than drain the old gas and I'm dreading doing this but if that's what I've gotta do...

[bearman1]

........that what you gotta do!

Kinda sounds like you may want to check the routing on your throttle/choke cables too. Almost sounds like your throttle cable is binding up, somewhere along the way. I'd check that, before ya start on the carbs.

[TXDrummer]

elgaot5, on 10 March 2012 - 01:23 PM, said:

Update: I hopped on just now and adjusted the clutch cable and got it to engage much sooner so that's taken care of. Still feels a little sticky though, not as smooth as my old one. Do they wear in over time?

I was able to push the choke in today after giving it a nice up hill ride. There was minimal stuttering and it idled fine. When I give it gas I will hold the throttle at the same position and the bike will rev slowly, then faster, then faster still until it gets to the correct rmp for the amount of gas I'm giving it. The rpms jump and aren't smooth so there is some jerking when getting into 1st and I can't fully engage quickly so it's a slow roll then kinda jumps into full speed. The other gears aren't as bad but there is that initial lack of power. Gonna check up on the forums for these symptoms. I have not done anything to the carbs other than drain the old gas and I'm dreading doing this but if that's what I've gotta do...

Your low speed circuits in the carbs are probably mucked up. Dirt and debris can restrict the tiny passages in the low circuits very easily, and that is not uncommon for these old bikes. It can also be the pistons not sliding freely in the carbs. Either will take a thorough carb job to clear up. Larry is the man, either the book or send them his way.

As for the jerking going into first, make sure your clutch is adjusted properly. Mine sometimes will jump into first very very slightly, but it doesn't "pull" with the clutch handle pulled in.

[ramprat06]

Courtesy Larry

[muzza]

The clutch cable issue is cos you got the wrong cable when you ordered a new one. You have a cable for a custom , probably - with higher bars so the cable has to be longer to suit. It will work the same but just stick out more because of the extra length.

I would also add that if you pulled something out of your fuel line then your carbs definately need a clean. Best to replace all the replaceables whilst you have them apart , that way you will know that all is right inside.

[elgaot5]

So I took the plunge and got Larry's book and an ultrasonic cleaner and wouldn't you know it - After weeks of waiting, debating, frustration, alleviation and a lot of patience the bike started right up! I was so nervous about pushing the button that I forgot to pull the choke out and it still started up strong!! This was my first "major" mechanical experience and it feels great to have actually pulled it off!

Unfortunately my tank picked up some more surface rust from just sitting there for 3 months. I'm debating whether or not I should try to get a liner on it, especially with the mixed reviews I've seen on the forum and online. I have an inline filter in place but I wouldn't want all that work to go to waste because of a rusty tank.

I only had it running for a couple of minutes but it sounded better than I remember. I'm excited to get the tank back on and get the carbs balanced.

[FADM Stern GNSF]

Once you complete;y clean a tank of rust the only way from stopping the rust from comming back is to

a) - ALways keep it full of gas
- line the tank

I lined mine with Kreem and it has worked great for 3 years and counting. Im not really sure what peoples complaints are about lining, just heard a lot of "my buddy said" and "my friend used it and it sucked" sort of things. Would be nice for anyone that has actually USED it to comment on the problems with the stuff (asside from it being expensive)

[lt1]

I would caution against Kreem. It's fine while it works, but it will start peeling loose and a Kreemed tank is seldom worth the effort, time and money to clean again. I would never by a bike with a Kreemed tank unless I had already budgeted for a new tank.

[ramprat06]

While I don't want to turn the debate to the tank liner issue, regarding Kreem, all the anecdotal things I've seen are preparation is the key to any lining. And we all know that each tank is going to be just as individual as the person doing the task. That alone is a lot of variables.

So, whether it is Kreem, Por-15, or the others mentioned in this forum....the key still resides in the amount of preparation, and limiting the variables. RTF instructions, I guess.

[elgaot5]

I think you're right Ramp, but unfortunately I am in a pretty cramped complex with no garage and I feel bad enough with the smell of gas, vinegar, carb spray, etc let alone acid and other crazy chemicals all over the place. I did a full night's vinegar wash and the tank got pretty darn clean. Got it filled up and took it for a spin and it sounded great!

I noticed my fuel filter was sitting right on my carbs and the heat was softening the plastic so I cut my ride and am going to be getting some longer fuel lines at lunch.

My clutch cable is still a little sticky since it's too long... I'll be messing with placement sooner than later but it's useable.

I have my idle adjustment needles pulled back to 2 1/2 turns per the cleaning instructions... Do I need to adjust these?