Cold starting issue (still)

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bubbachicken
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Cold starting issue (still)

Postby bubbachicken » Wed Dec 19, 2012 2:07 am

I know there must be a lot of folks out there with a similar question, but here it is yet again.

My bike (like all of these seem to) has a cold start issue. I can shoot some MAP sensor cleaner into the air filter, and the bike will fire right up instantly. I would rather not be doing that because I don't know the long term effects of this highly volatile substance (that is plastic safe, fortunately) directly into the system, but I am at my wits end on this. Once the bike starts, all is hunkey dorey. In addition, once the bike has run, as long as it is within perhaps an hour of cutting it off, it will again start quickly, instantly in the case of the exhaust pipes still being hot. I barely get the button pushed and it is running. I don't think the carbs are the issue because the bike runs so well once going. However, I can kill the battery attempting to start it normally if I don't use the MAP sensor cleaner spray (I suppose I could use WD-40 instead...). As I am riding almost daily to work this winter, this is going to be an issue I must address. I rode it to work yesterday (29 miles round trip, what a blast to ride!) and though it was a booger to start going and returning, it ran like a champ all the way there and back. Nary a hiccup.

Who knows of any way otherwise to make this gal behave like she should, or at least, save me from pouring a lot of potentially chemistry into her throat in the misguided effort to help her get going each day?

Also, is this going to still be an issue when the weather warms up???

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Volker_P
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Re: Cold starting issue (still)

Postby Volker_P » Wed Dec 19, 2012 2:24 am

In fact cold starting a CB650 is a bit tricky.
I twist the throttle several times to get some additional fuel by the accelerator pump. Then try to start. It will run a few seconds and die. Same again a few times until it stays alive.
This is piston carbs however, but not that different with CV carbs.
It is normal that it runs only on two or so for the first time, but after 30 seconds it should run on all four.

If you still have the vacuum shutoff installed on the carbs, try to bypass it. Hoses or valve itself might be a bit leaky.

Make sure that the flaps of both halves of the choke cam move synchronous and close completely. It is normal that the choke flips out by itself, however the bike will die then.

Turn out the manual idle knob until it looses contact to the throttle. Then turn it back to contact and another 3/4 turn in. Cold start would be tough if turned in further. It is all right that the choke opens the throttle a bit just before it is completely closed.

Really poor carb synchronization may be an issue, too. A visual synchonization should be sufficient.

Try closing the petcock some 100m before you stop the bike. It may start better with fresh fuel.

Consider to clean the starter from inside and clean out all related contacts. However the more typical starter power issues occur at warm engine.

How old are your plugs?
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forum links to common technical issues

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bubbachicken
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Re: Cold starting issue (still)

Postby bubbachicken » Wed Dec 19, 2012 10:52 am

Volker, that is a wonderful question about the plugs. I just happen to have four brand new shiny NGK's here for the bike, I just had been so involved with everything else, I forgot to install them! Thanks! They will go in today!!

I am going to take a look at the vacuum thing too. Mine seems so blow little gas bubbles now and then when I am trying to start the bike from a hole that a hose presumable could attach to, had a nipple been created there. I was assuming it was a vent, but now I wonder if perhaps there is a diaphram in there that has a leak in it! I will get that bypass done too... Wonder what I have here at home to plug it... A screw in the hose perhaps... I will pick up some hose nipple caps at work. Oh well, at least they are cheap...

I will check on the manual idle too, I was told the previous owner went through the carbs, but I have NO idea if he knew what he was doing. The bike runs amazingly well for a thirty year old machine when warm, so maybe he got most of it right, but still...

The starter seems very strong, it has zero issue on warm engine, and will crank several minutes on a cold one before dying out. If I let it cool a while it will resume, but by then I already have the carb spray out in frustration and the bike is running, warming up.

Oh, by the way, I fixed the oil leak (well the major one) at that head bolt on the far left. There are NO copper washers under ANY of the head bolts that I can see. The stripped one (since I am probably some day going to have to heli-coil it anyway) was temporarily fixed by starting a 1/4"x20 bolt into the start of the threads, then reinsertion of the original bolt and threading into the deformity but with a rubber washer under the head. Bolt tightened up some (stopped short of tight, I am fairly certain that would not have held to tight!) and mashed rubber washer down under the bolt head flange, Viola, no oil leak around bolt head.

Now, there is an Allen screw on the same side of the bike, on the outboard side of that housing (one of the two screws that are the same type in that position on that side), that seems to be seeping oil, but I can live with it if I have to tear things apart to get into it. It is exceedingly minor seepage and I don't know what that screw is supposed to do ("leak" is assuredly not the right thing, as the other one on that side, and the two on the right side of the bike don't do it-maybe they are broken! :lol: ).

bubbachicken
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Re: Cold starting issue (still)

Postby bubbachicken » Wed Dec 19, 2012 1:46 pm

UGH!

I can't get the center two plugs out without removing the fuel tank and (I am assuming) the tach insert!!! Why the H E Double-toothpicks did they design this bike that way? Outboard plugs were tan but definitely had miles on them from electrode wear indications as well as the corrosion around them, but fortunately each was evenly worn and colored. No soot (nice!). I installed the two in that I could before I have to go to work, will have to work on the other two tomorrow morning... Bike runs great still, fortunately, even with two likely worn plugs still installed. Wires look great and connect solidly. That is one less heartache and a blessing in itself!

I am pretty stoked however about the cold starting solution Volker, it does take some throttle pumping, but the bike WILL start eventually with enough toying with the grip on a full choke application. It then runs at 4K for a while, until I can press the choke back in perhaps 1/4 inch from fully open. I imagine that after a few minutes under load I can close it the rest of the way, but to be honest, in my trip 2 days ago, by the time I thought about it, I was already at work.

I was looking at my saddle bag situation too. I think I can use some of those universal headlight clamps, some EMT conduit, some paint, and a pipe bender and make some rather cool saddle bag supports (I know, ratty, but hey, it IS a 30 year old machine, and I am not intentionally restoring it :roll: ).

I am thinking that I might be able to create some solid supports that will keep the bags off the shocks and at the same time keep them square to the bike. Right now....not so much... I am also not terribly fond of the X formed by bungees across the back of the seat, holding the saddle bag set down (because under the seat mounting puts them directly on top of the exhaust pipes). I find it interesting that though the pipes themselves get hot, the mufflers are barely warm to the touch after a 15 mile ride. I would have thought they would get hot, but they don't. Also, the exhaust gasses themselves are not hot either out of the mufflers, lukewarm at best. Is that strange? The exhaust off my truck gets hotter than that, and you SURE don't want to touch the hot muffler on that Silverado (2500 HD)....

So how do you guys keep the bags attached if you cannot run the connect under the seat? Are you using racks and doing something like I am considering, or have you come up with other ways of doing this?

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Folsoml
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Re: Cold starting issue (still)

Postby Folsoml » Wed Dec 19, 2012 8:47 pm

Volker_P wrote:In fact cold starting a CB650 is a bit tricky.
I twist the throttle several times to get some additional fuel by the accelerator pump. Then try to start. It will run a few seconds and die. Same again a few times until it stays alive.


This is exactly how I have to start mine the first time of the day.
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My Current Bikes: 2005 HD FLHTCUI Electra Glide Ultra Classic, 2007 Yamaha Vino,

bubbachicken
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Re: Cold starting issue (still)

Postby bubbachicken » Wed Dec 19, 2012 11:06 pm

Well, it works like a charm, so that is now how I will as well. It worked splendidly, in fact! No more starting fluids for me.. Just twist about ten times, then pull choke, press button, she fires up and the second or third time I can keep her running. I am then good for a couple hours after I shut her down. I am still fighting with the choke though, my bubba fix is not the best. I used a universal control cable (the kind in the metal coil with the homemade tie point at the choke lever end to keep it from coming loose??) and it seems to pinch at the clamp point over the choke control on the carbs. It sure is a bear to use. I am going to have to hunt me down a real choke cable someplace... This thing sux.... Herky jerky application at best, and a bear to adjust while in transit! :shock:

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Volker_P
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Re: Cold starting issue (still)

Postby Volker_P » Thu Dec 20, 2012 2:21 am

bubbachicken wrote:UGH!

I can't get the center two plugs out without removing the fuel tank and (I am assuming) the tach insert!!! Why the H E Double-toothpicks did they design this bike that way?


Get a nowadays sports bike and be happy about removing the fairing and sometimes even the radiator to get your plugs out. :lol:

In fact for a CB650 you have to use the choke longer than for most other bikes. So good to have a choke that does not flip back completely by itself. I bent the solid part of the choke cable a bit so it won't go back that easily. :wink:
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forum links to common technical issues

If you really like this site and you would not like to see it vanish soon, have a look there: Urgent: Future of HondaCB650.com Forum

bubbachicken
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Re: Cold starting issue (still)

Postby bubbachicken » Thu Dec 20, 2012 10:05 pm

Volker_P wrote:
bubbachicken wrote:UGH!

I can't get the center two plugs out without removing the fuel tank and (I am assuming) the tach insert!!! Why the H E Double-toothpicks did they design this bike that way?


Get a nowadays sports bike and be happy about removing the fairing and sometimes even the radiator to get your plugs out. :lol:

In fact for a CB650 you have to use the choke longer than for most other bikes. So good to have a choke that does not flip back completely by itself. I bent the solid part of the choke cable a bit so it won't go back that easily. :wink:


I have to literally tap/pound the choke closed or open. That is with the NEW cable too... It is jerky as heck and there is NO way to think I am consistent with it. The end is not even precise. I need to look for some of those universal ends to clamp onto the cable or something, right now it is a wad of wire wrapped around a discarded piece of the spring sleeve that was removed from the original length of the aftermarket cable, so if not careful, fully depressing the choke unhooks the cable from the lever!

I have the original cable, but the knob is missing and the cable itself is solidly jammed in place within the black plastic casing. I wonder, is there a graceful way to remove it from the sleeve housing and lube it up, reinstall it, and get use of it as it was supposed to be? I could then use some chain lube or white lithium grease or something and it should stay decent I would think... Have you ever tried anything like that?

At this point, I am considering even attempting to relocate the control or make a mechanical linkage for it, so that I can make it work smoothly. The carb part is smooth as silk, the cable SUCKS (granted, it IS an aftermarket, non-proper for application, generic, lawn equipment or remote release control cable I am using in place of the real deal).

onepieceatatime
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Re: Cold starting issue (still)

Postby onepieceatatime » Thu Dec 20, 2012 10:23 pm

Choke cables are still available from the Honda Dealer at reasonable prices.
Folsoml wrote: Good judgement comes from experience. Experience comes from bad judgement. :lol:


1977 CB750K
1977 CB750K
1978 CB400A
1980 CB650C
1980 CB650
1982 CB900F
1982 CM450A
1997 GL1500SE

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Volker_P
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Re: Cold starting issue (still)

Postby Volker_P » Fri Dec 21, 2012 2:22 am

One could try to boil it in oil (and make use of this opportunity burning down your home, too :lol:) but I am not sure if it is worth it because the wires will be brittle from corrosion anyway.
Cosky's great (free) online manual: http://cosky0.tripod.com

forum links to common technical issues

If you really like this site and you would not like to see it vanish soon, have a look there: Urgent: Future of HondaCB650.com Forum

bubbachicken
Posts: 368
Joined: Tue Nov 13, 2012 2:19 pm

Re: Cold starting issue (still)

Postby bubbachicken » Fri Dec 21, 2012 10:48 am

onepieceatatime wrote:Choke cables are still available from the Honda Dealer at reasonable prices.


Yeah, that is what I thought. MY Honda dealer told me they had very few items left, and that this cable was not one of them. He did have the headlight bulb, but I had that at work too, as it turned out-the one they sold me was precisely the same one I bought at work (same wattage and all)!

I guess I have to go to another part of the state for a different Honda dealer. This is one of the downsides to living in a part of the state with such low population, service is usually crap and inventories are not far behind...

bubbachicken
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Re: Cold starting issue (still)

Postby bubbachicken » Fri Dec 21, 2012 10:55 am

Volker_P wrote:One could try to boil it in oil (and make use of this opportunity burning down your home, too :lol:) but I am not sure if it is worth it because the wires will be brittle from corrosion anyway.



Yeah, that was my thought too. I know there is rust at the top end (the PO had been using a pair of Vice Grips to operate the choke, so there is no way short of epoxy to put an end on it, assuming I could locate one somehow) and he had to pull like heck to get the thing to move for him, which is why I replaced it to begin with. The problem is that my replacement cable is stiff too, and it just is not very limber internally. The least bend and it catches, and that is a problem I am not happy with. I have considered rerouting it, but I don't know how to eliminate that last bend to get to vertical at the carbs (that is where it catches). I suppose I could soak the new cable in something, but I already doused it in WD-40 before installation, that worked for, oh, maybe NOT AT ALL.

Seems someone could get rich making universal cables that are silky smooth inside but that can do full loops and stay smooth. Make them like the universal one I got, so that the length can be trimmed, but that have a little end piece that can be set-screwed or otherwise attached for the sort of connection you need. I would have paid 20 bucks to get that, no problem! I know a lot of other people would too!

onepieceatatime
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Re: Cold starting issue (still)

Postby onepieceatatime » Fri Dec 21, 2012 12:02 pm

bubbachicken wrote:
Volker_P wrote:One could try to boil it in oil (and make use of this opportunity burning down your home, too :lol:) but I am not sure if it is worth it because the wires will be brittle from corrosion anyway.



Yeah, that was my thought too. I know there is rust at the top end (the PO had been using a pair of Vice Grips to operate the choke, so there is no way short of epoxy to put an end on it, assuming I could locate one somehow) and he had to pull like heck to get the thing to move for him, which is why I replaced it to begin with. The problem is that my replacement cable is stiff too, and it just is not very limber internally. The least bend and it catches, and that is a problem I am not happy with. I have considered rerouting it, but I don't know how to eliminate that last bend to get to vertical at the carbs (that is where it catches). I suppose I could soak the new cable in something, but I already doused it in WD-40 before installation, that worked for, oh, maybe NOT AT ALL.

Seems someone could get rich making universal cables that are silky smooth inside but that can do full loops and stay smooth. Make them like the universal one I got, so that the length can be trimmed, but that have a little end piece that can be set-screwed or otherwise attached for the sort of connection you need. I would have paid 20 bucks to get that, no problem! I know a lot of other people would too!



I bought an aftermarket one (can't remember where) that was not very good, so I went to the dealer and they ordered one for me. Here is the online parts listing. You can order from them, or get the part number and tell your dealer to order it for you.

http://www.servicehondapsn.com/fiche_select.asp
Folsoml wrote: Good judgement comes from experience. Experience comes from bad judgement. :lol:


1977 CB750K
1977 CB750K
1978 CB400A
1980 CB650C
1980 CB650
1982 CB900F
1982 CM450A
1997 GL1500SE

bubbachicken
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Re: Cold starting issue (still)

Postby bubbachicken » Fri Dec 21, 2012 10:13 pm

onepieceatatime wrote:
bubbachicken wrote:
Volker_P wrote:One could try to boil it in oil (and make use of this opportunity burning down your home, too :lol:) but I am not sure if it is worth it because the wires will be brittle from corrosion anyway.



Yeah, that was my thought too. I know there is rust at the top end (the PO had been using a pair of Vice Grips to operate the choke, so there is no way short of epoxy to put an end on it, assuming I could locate one somehow) and he had to pull like heck to get the thing to move for him, which is why I replaced it to begin with. The problem is that my replacement cable is stiff too, and it just is not very limber internally. The least bend and it catches, and that is a problem I am not happy with. I have considered rerouting it, but I don't know how to eliminate that last bend to get to vertical at the carbs (that is where it catches). I suppose I could soak the new cable in something, but I already doused it in WD-40 before installation, that worked for, oh, maybe NOT AT ALL.

Seems someone could get rich making universal cables that are silky smooth inside but that can do full loops and stay smooth. Make them like the universal one I got, so that the length can be trimmed, but that have a little end piece that can be set-screwed or otherwise attached for the sort of connection you need. I would have paid 20 bucks to get that, no problem! I know a lot of other people would too!



I bought an aftermarket one (can't remember where) that was not very good, so I went to the dealer and they ordered one for me. Here is the online parts listing. You can order from them, or get the part number and tell your dealer to order it for you.

http://www.servicehondapsn.com/fiche_select.asp


I must be half moronic, because I cannot get that link to show me the cable, let alone tell me a part number. All the vehicles listed in that link are modern or are ATVs and such, and the only listings for the CB650C are for a few items (most are discontinued of course) but do not even MENTION a choke cable... Maybe I missed it somehow, but I don't know if that is the site you were thinking it was..?

onepieceatatime
Posts: 323
Joined: Wed Nov 02, 2011 5:12 am
Location: Franklin County, Pennsylvania, USA

Re: Cold starting issue (still)

Postby onepieceatatime » Sat Dec 22, 2012 8:43 am

bubbachicken wrote:I must be half moronic, because I cannot get that link to show me the cable, let alone tell me a part number. All the vehicles listed in that link are modern or are ATVs and such, and the only listings for the CB650C are for a few items (most are discontinued of course) but do not even MENTION a choke cable... Maybe I missed it somehow, but I don't know if that is the site you were thinking it was..?



I think you said your bike was an '81 Custom...
http://www.servicehondapsn.com/fiche_select2.asp?category=Motorcycles&make=Honda&year=1981&fveh=132941

That should take you directly to the listings for that bike, but when I looked, it is showing the choke cable discontinued now...

Choke cable is listed under Handlebar@Topbridge
Part number 17950-460-730

I bought mine about 4 months ago, the dealer ordered it for me, so I figured they were still around and didn't actually look before I posted that. :oops:

I think the aftermarket one I bought was motion pro, but I can't find one from them now either.
Folsoml wrote: Good judgement comes from experience. Experience comes from bad judgement. :lol:


1977 CB750K
1977 CB750K
1978 CB400A
1980 CB650C
1980 CB650
1982 CB900F
1982 CM450A
1997 GL1500SE


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