Topic: please help..have to sell my bike

[jmill0823]

  I just bought an 81 CB650 Custom for $1100.  It runs pretty well, the body is in really good shape (paint is perfect).  The front brakes are out but I have a master cylinder kit on the way to repair them.  It also backfires quite a bit which I think would be solved by cleaning out the carbs and stuff (yes..no???).  The problem is I didn't think the purchase through-I'm in college, kind of broke, and I don't have a good place to park it at my apts, I'm thinking the smartest thing for me to do is sell it and buy another one when I'm in a better position to do so.  Could anyone tell me after I fix the problems what I should sell it for?? I was thinking 1400 or 1500..is that too high??  It comes with a rear luggage rack/padded seat, the original manual, and a helmet and it has a new battery. 

[douglascoolgrey]

I don't know what its worth. Where are you going to school? What did you pay for it?

By the way, college is the perfect place to not think before you do something. I say you keep the bike, skip out on your rent for a month or two until you're in the black again, and then maybe get another roommate. There's more room on the couch, right? If you really need money, you can skimp on some non-essentials like books and food.

Besides, you're in college. Nothing says "Take me back to your place" better than "Have you ever riden on the back of a motorcycle?"

[jmill0823]

Thanks for the advice..since I posted I have had a lot of second thoughts about selling it but now I'm very back and forth.  I paid $1100 for it, but it has 17000 miles and the front brakes are out.  I am about to fix the brakes, and I really do want to keep it but it might end up needing more work soon.  What should I sell it for?

[Gordon]

It will sell for less than you paid, I can almost guarantee.

I didn't want to be the one to say it, but he may be right.  The 650 custom, while a great bike, isn't really in great demand. 

I say keep it!  It's cheap transportation, gets great mileage, insurance is a drop in the bucket, and like Douglass said, chicks dig bikes.  As far as maintenance goes, you've got the best resource in the world for these bikes right here!  If you don't have a covered parking spot, buy an inexpensive cover to keep the elements off of it.  If you sell it, you'll regret it someday. 

[jmill0823]

well yall have me convinced, but after coming back from visiting home for the weekend...it wont start anymore.  It will run as long as I keep revving it and then it dies.  Carbs need cleaning?? Rebuilding??

[Gordon]

It will run as long as I keep revving it and then it dies.  Carbs need cleaning?? Rebuilding??

What are you asking us for?  You're on your own, man! 

But really, start with the simple solutions and work your way up.  It could be as easy as turning in the idle speed screw to keep it at a higher RPM until the engine is warm enough to idle where it's supposed to.  What exactly are you doing when you start it?  What does it sound like?  Are all the pipes getting warm, or are one or more still cold?  Give us a step-by-step, and we'll go from there. 

[jmill0823]

Well when I tried to crank it today the battery was dead.  After hooking it up to my cars battery it just turned over a lot and there was nothing. The guy who sold it to me had replaced the plugs and I assume he gapped them properly because he knows a thing or two about mechanics.  Who knows though.  It finally started up for a second and then died.  After that nothing.  I went and got some start fluid and it was able to start with that pretty easily but when I gave it gas it died down and then went back up.  This is all strange because the day I bought it (last thursday) and the next day I was able to get it cranked pretty easily and it idled okay.  Then it sat for three days while I was gone and all this is happening.  I see the idle screw but I don't know which way to turn it (I adjusted it slightly while it was running and the idle didnt change)  I am thinking the carbs are out of sync.  I saw in another post to fill the carbs with some combustion chamber cleaner and leave it for 24 hrs and then drain it out.  I am sure the carbs are dirty but I don't know if cleaning them without resyncronizing them will really help.  I am so lost-this is my first bike I have NO money to pay to have it worked on and I havent been able to ride it since I bought it.  I really really appreciate any help anyone can offer.   

[egar]

Get ready to invest a lot of time on your bike. I spent many nights and weekends getting mine to run, but I had the luxury of time and bought the bike to learn its mechanics, not necessarily as a main source of transportation. Now that it is running, I'm getting it registererd for the road, but I expect there will be many more long nights, which is OK, because they're fun bikes.

[Gordon]

OK. you're getting ahead of yourself.  If it idled fine a few days ago, chances are the carbs are at least still good enough to get it running now.  If your battery is dead, the bike won't idle once you disconnect it from your car's battery.  The ignition system needs power from the battery to run at low RPMs.  Either charge it up, or if it's a goner, get a new one. 

I'd still like a step-by-step of your starting procedure.  Are you using the choke?  The idle screw turns clockwise to raise idle, and counter-clockwise to lower.  There are many simple things that could cause this, but we need a starting point.

[douglascoolgrey]

Where do you live, jmil? Know anyone with tools / experience / place to work on the bike? Who do you ride with? (I'm sorry, you're a college boy... With whom do you ride?) Is there a motorcycle club at your school? How about the geeks in the engineering department. They guys may be clueless, but they've got access to tools, killer shops, and big books.

Do you have a manual?

You may have paid too much for a bike with issues, but you'll never forget the first time you get your own bike running again. Or the first time it breaks down far away from home and you have to make it home somehow. Or the first time you drop it. Or the first time you can't remember where you parked and you think its stolen. Or the first time your future wife washes and waxes it for you wearing only a bikini (maybe that's just me).

[jmill0823]

okay i did buy a battery charger, just havent used it yet, i will now.  The guy who sold it to me said most hondas that old take a long time to warm up and the only way it will run is to keep the choke all the way out.  i am just pulling the choke out, turning everything on (key, switch, fuel) and turning it over.  after it wont start i give it a little gas, but i was told that doesnt help because it has a fuel pump deal.  i live in athens, ga (UGA town).  I have decent tools and Ive done a lot of work on cars, but I am not great at diagnosing problems. 

[Gordon]

Is your battery charger a low-amp one?  Anything over 2 amps will fry a motorcycle battery.  The bike's P.O. was right about needing the choke.  The later model sohc4's are jetted pretty lean, so are usually cold-blooded. 

Once you get the battery charged up, if it still won't start, check to make sure you have fuel to all the cylinders.  Open up the carb drain screws and see if gas comes out of each float bowl.  If you have fuel to all cylinders, pull the spark plugs.  If they're wet with fuel, dry them off and check to see if they're sparking.  A lot of times, if the engine doesn't start right away, the plugs just get soaked with fuel and won't spark under compression. 

You'll get it figured out!

[DammitDan]

Whoop, another 650!  We're gonna take this forum over, ya hear me?  Burn baby, Burn!

Ahem.  Back to business.

CB650s don't have a fuel pump, but rather a gravity delivery system... On models after 1981 the carbs maintain a constant vacuum on the fuel line, so it takes the engine running to get fuel sucked from the tank and through the carbs.  That's why you had to inject starter into the carbs initially (and also why we don't have to turn off our petcocks like all those other SOHC suckas out there! )

If only Athens were closer to Nashville...  I would make a hop skip and a jump right down there and bring all my tools with me!

[pmpski_1]

I overpaid for a bike that ran when the dude sold it to me too. If you're a good listener and can figure things out these guys will have you up and running in no time. If you're hard headed like me then maybe you'll be riding sometime next fall.

Either way, keep it and fix it. You'll never pay too much for a bike again.

[Geeto67]

Well when I tried to crank it today the battery was dead.  After hooking it up to my cars battery it just turned over a lot and there was nothing. The guy who sold it to me had replaced the plugs and I assume he gapped them properly because he knows a thing or two about mechanics.  Who knows though.  It finally started up for a second and then died.  After that nothing.  I went and got some start fluid and it was able to start with that pretty easily but when I gave it gas it died down and then went back up.  This is all strange because the day I bought it (last thursday) and the next day I was able to get it cranked pretty easily and it idled okay.  Then it sat for three days while I was gone and all this is happening.  I see the idle screw but I don't know which way to turn it (I adjusted it slightly while it was running and the idle didnt change)  I am thinking the carbs are out of sync.  I saw in another post to fill the carbs with some combustion chamber cleaner and leave it for 24 hrs and then drain it out.  I am sure the carbs are dirty but I don't know if cleaning them without resyncronizing them will really help.  I am so lost-this is my first bike I have NO money to pay to have it worked on and I havent been able to ride it since I bought it.  I really really appreciate any help anyone can offer.   

dude, check 1) fuel petcock - make sure it is on or in res. Most likely it is clogged so pull it out and clean it, and  2) that the bike actually has gas in it. Your problem doesn't sound like carbs - it sounds like fuel delivery. carbs are a big job for a noob so chec the fuel system first. I once bought a cb750 that wouldn't start for $360. the problem - 2 feet of fuel line under the tank, kinked in a lot of spots.

The brake rebuild isn't a big job but if you are new to working on bikes you may want to take it to the shop for it's first time. After that maintain it and get comfortable with it. If you are familar with bleeding brakes on cars it's the same on bikes so maybe you would be up to the job after all. .

I'm not going to pussyfoot around you overpaid for your rig. That puts you between a rock and a hard place. If you sell it you lose money and if you keep it you lose money but maybe not as much. Remember why you bought it in the first place - if you still have the passion for it take a deep breath and face your fear of being in over your head. This thing should never get inthe way of your school work (your drinking and partying it can get in the way of), you pay more for college than for your bike. Buy a cover - find a parking spot, wrench on the thing and have some fun.

[jmill0823]

the battery charger is made for motorcycles, so that should be okay.  I have a full tank of premium gas, and the petcock (i assume that is the fuel switch) is in the on position, i dont think anything is wrong with that.  the battery is charging now.  Ill go start it and see what it does

[jmill0823]

Okay now what in the world is going on.  When I hook the battery charger up it says charging, and when I come back the red light indicating "trouble" is on.  The charging seems to be working as the bike will turn over, but why doesnt it say charged instead of "trouble".  Anyways when it is turning over Im getting nothing.   

[jmill0823]

well the guy is telling me that i burned up the rectifier brigde and fried the battery by hooking it up to my car battery(while car was off) to charge the battery.  is he right??

[jmill0823]

i just took the battery to auto zone and its bad!!!!  it was someones advice on this forum to jump a bike off using your car battery (with the car not running)...i did so and now im out a new battery..ill try to get it replaced but geez.  like i said the guy who sold me the bike thinks i burnt up the rectifier bridge when i did that..but if i take a spark plug out and touch it to the cylinder hole i see spark.  so that couldnt be the problem coudl it?  it has to be a fuel issue right???

[douglascoolgrey]

Is the guy who sold you the bike the same guy who said there was a problem with the fuel pump? Is he also the guy that told you the bike was running fine when he sold it to you? That's the same guy who charged you too much, right?

[Geeto67]

i just took the battery to auto zone and its bad!!!!  it was someones advice on this forum to jump a bike off using your car battery (with the car not running)...i did so and now im out a new battery..ill try to get it replaced but geez.  like i said the guy who sold me the bike thinks i burnt up the rectifier bridge when i did that..but if i take a spark plug out and touch it to the cylinder hole i see spark.  so that couldnt be the problem coudl it?  it has to be a fuel issue right???

I jump bike batteries off of car batteries all the time (while the car is off). Deosn't fry the battery unless you leave it on there for a long time. Chances are your battery was bad to begin with (it was probably sulfated from sitting). You know the rules about internal combustion engines If you have air and have spark you have two of the three things to make it run. The problem is in your fuel delivery somewhere. When you unhook the fuel line and turn the petcock on does it dump fuel? Is the fuel hooked up to the right feed (on those carbs there is a fuel inlet and a vacume inlet. You would not believe how many 550s and 650s I have seen with fuel going into the vacume inlet. IF you burned up the rectifier you should not have spark.

[jmill0823]

I will try doing what you said Geeto.  I did leave the car battery hooked to it for like 30 min while i was trying to get it cranked.  While everyone is looking here instead of starting a new thread -> I just got my master cylinder rebuild kit in the mail.  I think I can figure it out from most of the posts Ive read, but am slightly confused. Is the ACTUAL master cylinder itself under the master cylinder reservoir or is it somewhere else on the bike?? What do I remove to replace with the new parts?? I sound like an idiot I know.

[jmill0823]

EUREKA!! The first good news to come from my mouth (fingers in this case)!!!  The guy who sold me this is starting to lose his credibility.  I already ordered the master cylinder kit at 30 bucks.  I went out to start installing it and I had zip tied the brake handle down to build up air.  I cracked the nut on the line that goes from the cylinder down the calipers and a lot of air came out.  So i just tightened it back down and the brakes work amazingly!!  Hopefully I can get my money back on this kit.  Now to get the bike running

[Gordon]

Glad to hear the good news on the brakes!  I think at this point it's best to forget anything the PO told you and start fresh.  Do what Geeto says and check that fuel is flowing from the tank.  After confirming that, you need to open the carb drain screws and make sure that the fuel is getting into the carbs.  If the carbs have gas in them, and the plugs are wet when you pull them out after attempting to start, and they are getting spark, then you need to check for compression in each cylinder.  If you have fuel, spark, and compression, then it's safe to say that your problem is not with the carbs or coils/spark plugs.  The next step is to check and adjust the ignition timing and valve clearances, but chances are the problem lies somewhere within the combustion engine "triangle". 

[cub]

I bought myself an overpriced CB500/650 last year which didn't run properly. I've put more money into it than I had planned but I have also learned loads of things so I'm happy. Well, not all the time but over all. 

If you're on a budget then check out http://cb650.net/ where you'll find much information as well as manuals. I have some stuff on my comp that might be useful and the Clymer in my bookshelf so I might be able to provide some info.

Don't sell it! Like the others already have said you probably won't get what you paid for it. Keep it, learn and make it run. That way you'll more things out if it than just a bike. You just noticed the nice feeling you get when you fixed the brakes. =) Then you will learn more which is always good. And last but not least you can tell all the girls that you fixed it yourself. SCORE!