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Offline cb750fbomb

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Help with stalling after warm up
« on: February 07, 2009, 12:34:54 PM »
Hi everyone. Any help anyone could give me with this problem would be great. If this is posted elsewhere feel free to link me up. I'm half asleep right now so I'm sorry if I'm confusing.
My bike keeps stalling and she seems to run rougher the warmer she gets. I had to start it and stop it several times today and she sounds rougher each time I start her up. I started her up and she runs a little rough, as to be expected. and then she starts running and sounding good. Turn off ignition, start it up and it sounds good. Turn off ignition, start it up and starts sounding rougher and rougher. After doing this the third or fourth time it sounds bad. This is just sitting parked in the back yard. When I get her out on the road it gets worse fast, stalling more and more until she just won't start at all. She cools down and the cycle can start over again.
It's firing on all cylinders, but from the little that I know it almost sounds like it just isn't getting enough fuel. It also seems to be using more fuel than it should. There's an in line fuel filter that I'm going to change for the heck of it, but it doesn't look filthy or clogged up.
She didn't do this when I first got her and the longest she's set with gas in the tank is 2 weeks. I rode one night and the next night she started doing this.
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Offline joeb

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Re: Help with stalling after warm up
« Reply #1 on: February 07, 2009, 01:32:03 PM »
Open up your float bowl drains and collect what comes out and see if you  got some crud in them.  How old are your ignition parts? just throwing out some things to look at.  I'm pretty sure someone else will jump in with some mor suggestions.
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Offline scondon

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Re: Help with stalling after warm up
« Reply #2 on: February 07, 2009, 02:12:15 PM »
Are you running pods? Is your choke linkage stuck open from interference with #2,#3 pods? I can't tell from your avatar whether that's a stock airbox or pods.

   Sounds like an over rich condition to me, which is why I think your choke is stuck. These carbs are jetted to run lean.
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Offline cb750fbomb

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Re: Help with stalling after warm up
« Reply #3 on: February 07, 2009, 10:59:19 PM »
Quote from: joeb on February 07, 2009, 01:32:03 PM
Open up your float bowl drains and collect what comes out and see if you  got some crud in them.  How old are your ignition parts? just throwing out some things to look at.  I'm pretty sure someone else will jump in with some mor suggestions.
I'll check those float bowls. I don't know how old the ignition parts are. I haven't had the bike long.
Quote from: scondon on February 07, 2009, 02:12:15 PM
Are you running pods? Is your choke linkage stuck open from interference with #2,#3 pods? I can't tell from your avatar whether that's a stock airbox or pods.

   Sounds like an over rich condition to me, which is why I think your choke is stuck. These carbs are jetted to run lean.
I am running K&N pods. Just cleaned and oiled them. I'll check out the choke linkage and spray some cleaner around as well. I've noticed that the valve under carb #2 drips as well. It doesn't always do it, but it did it today. What does it weeping gas mean?  

I'll try all of the above in the morning when I get home from work.
« Last Edit: February 08, 2009, 12:27:55 AM by cb750fbomb »
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Offline TwoTired

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Re: Help with stalling after warm up
« Reply #4 on: February 08, 2009, 12:32:54 AM »
Did you over-oil the pods, choking of the air intake?
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Offline cb750fbomb

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Re: Help with stalling after warm up
« Reply #5 on: February 08, 2009, 12:46:34 AM »
Quote from: TwoTired on February 08, 2009, 12:32:54 AM
Did you over-oil the pods, choking of the air intake?
I didn't know this was possible, but I don't think so. I really didn't go crazy with oiling them and followed directions. How would I know? Should I pull them and see if it does the same thing?
« Last Edit: February 08, 2009, 12:55:51 AM by cb750fbomb »
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Offline TwoTired

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Re: Help with stalling after warm up
« Reply #6 on: February 08, 2009, 12:50:41 AM »
Quote from: cb750fbomb on February 08, 2009, 12:46:34 AM
Quote from: TwoTired on February 08, 2009, 12:32:54 AM
Did you over-oil the pods, choking of the air intake?
I didn't know this was possible, but I don't think so. I really didn't go crazy with oiling them and followed directions. How would know? Should I pull them and see if it does the same thing?

Seems a reasonable and fairly quick test.  It IS possible to over oil the pods.

Cheers,
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Offline cb750fbomb

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Re: Help with stalling after warm up
« Reply #7 on: February 08, 2009, 12:55:29 AM »
Quote from: TwoTired on February 08, 2009, 12:50:41 AM
Quote from: cb750fbomb on February 08, 2009, 12:46:34 AM
Quote from: TwoTired on February 08, 2009, 12:32:54 AM
Did you over-oil the pods, choking of the air intake?
I didn't know this was possible, but I don't think so. I really didn't go crazy with oiling them and followed directions. How would know? Should I pull them and see if it does the same thing?

Seems a reasonable and fairly quick test.  It IS possible to over oil the pods.

Cheers,

I'll try that when I get home from work.
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Offline cb750fbomb

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Re: Help with stalling after warm up
« Reply #8 on: February 08, 2009, 10:00:31 AM »
When I drained the bowls there was dark sediment with reddish flakes/bits that came out. Same results on each carb. Assuming that the red may be from the filter oil. (?)
The choke is working fine. The valves all move in unison through the range of the choke engage/disengage. But.....
I couldn't keep her running and the multimeter is showing that the battery is all the way down to 10 v. When I hit the starter it went down to 7 v and below with nothing but a click. This is a new battery that i picked up yesterday and the second new one in 2 months. I guess I need to learn more about electricity real quick. Any tips on checking alternator's, rectifiers and regulators? I'll be reading my Clymer and multimeter instructions.               
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Offline WFO

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Re: Help with stalling after warm up
« Reply #9 on: February 08, 2009, 10:06:15 AM »
Quote from: cb750fbomb on February 08, 2009, 10:00:31 AM
When I drained the bowls there was dark sediment with reddish flakes/bits that came out. Same results on each carb. Assuming that the red may be from the filter oil. (?)
The choke is working fine. The valves all move in unison through the range of the choke engage/disengage. But.....
I couldn't keep her running and the multimeter is showing that the battery is all the way down to 10 v. When I hit the starter it went down to 7 v and below with nothing but a click. This is a new battery that i picked up yesterday and the second new one in 2 months. I guess I need to learn more about electricity real quick. Any tips on checking alternator's, rectifiers and regulators? I'll be reading my Clymer and multimeter instructions.               

Heck if that stuff came out of the carbs you might be clogging up the jetsand lightly oil the pods i doubt those red flakes are oil but probably some old varnish that collected inside the carbs it may be starving for air as TT alluded.
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Offline Duke McDukiedook

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Re: Help with stalling after warm up
« Reply #10 on: February 08, 2009, 10:08:22 AM »
Check the faq section here to link to the Honda manual for download, Clymer and Haynes glosses over some of the details involved in checking these components. Sounds like you do have an electrical problem along with a possible fuel delivery problem. Check your fuel and spark.

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Re: Help with stalling after warm up
« Reply #11 on: February 08, 2009, 10:28:47 AM »
A guess might be that the lower the battery gets, the less voltage available for the ignition system to work properly. Try charging the battery and see if the running straightens out. Then find out why the battery is discharging. A recommendation: analyze ONE system at a time, and VERIFY your repairs before moving on to another system. my .02...jim
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Offline TwoTired

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Re: Help with stalling after warm up
« Reply #12 on: February 08, 2009, 10:31:56 AM »
Isn't K&N filter oil purple?

Reddish flakes in the bowls are usually from rust and dried fuel deposits.
Does your fuel tank have rust?

Electrical... 
Fully charge your battery disconnected from the bike, and let it rest 2 hours.   The voltage should be 12.6 v minimum, assuming the battery is at 70-ish degrees.  Anyway, measure and report.

Connect the battery to the bike and kick start the motor.  Electric starters draw 150 amps, depleting the battery.

Now measure the battery voltage at idle, 2000, 3000, 4000, and 5000 RPM.  It is handy to have those same set of numbers with the headlight off or the headlight fuse removed.

Higher wattage headlights, 3 ohm coils, etc., can make the RPM where the battery starts charging, higher, even with a good charging system.

Cheers,
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Offline cb750fbomb

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Re: Help with stalling after warm up
« Reply #13 on: February 08, 2009, 11:01:17 AM »
Quote from: TwoTired on February 08, 2009, 10:31:56 AM
Isn't K&N filter oil purple?

Reddish flakes in the bowls are usually from rust and dried fuel deposits.
Does your fuel tank have rust?

Electrical... 
Fully charge your battery disconnected from the bike, and let it rest 2 hours.   The voltage should be 12.6 v minimum, assuming the battery is at 70-ish degrees.  Anyway, measure and report.

Connect the battery to the bike and kick start the motor.  Electric starters draw 150 amps, depleting the battery.

Now measure the battery voltage at idle, 2000, 3000, 4000, and 5000 RPM.  It is handy to have those same set of numbers with the headlight off or the headlight fuse removed.

Higher wattage headlights, 3 ohm coils, etc., can make the RPM where the battery starts charging, higher, even with a good charging system.

Cheers,

No rust in my tank that I know of. I'll report back soon with results from the rest. I hope it stays warm so I can fix my ride. :)
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Offline cb750fbomb

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Re: Help with stalling after warm up
« Reply #14 on: February 10, 2009, 09:13:29 AM »
Quote from: TwoTired on February 08, 2009, 10:31:56 AM
Isn't K&N filter oil purple?

Reddish flakes in the bowls are usually from rust and dried fuel deposits.
Does your fuel tank have rust?

Electrical... 
Fully charge your battery disconnected from the bike, and let it rest 2 hours.   The voltage should be 12.6 v minimum, assuming the battery is at 70-ish degrees.  Anyway, measure and report.

Connect the battery to the bike and kick start the motor.  Electric starters draw 150 amps, depleting the battery.

Now measure the battery voltage at idle, 2000, 3000, 4000, and 5000 RPM.  It is handy to have those same set of numbers with the headlight off or the headlight fuse removed.

Higher wattage headlights, 3 ohm coils, etc., can make the RPM where the battery starts charging, higher, even with a good charging system.

Cheers,

The readings with the headlight:
2000 - 12.68
3000 - 13.14
4000 - 14.15
5000 - 13.94
I went to take the same readings with the headlight fuse out and got 12.69 @2000 rpm. It then started running very rough, LOUD and it was popping getting up to 3000 rpm. So loud that I released the throttle and it then immediately died. Anyone know a good shop in Nashville? What did I get myself into getting a motorcycle without getting a motorcycle mechanics certification or something? I'm not giving up, but.............
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Offline TwoTired

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Re: Help with stalling after warm up
« Reply #15 on: February 10, 2009, 09:52:53 AM »
Quote from: cb750fbomb on February 10, 2009, 09:13:29 AM
Quote from: TwoTired on February 08, 2009, 10:31:56 AM
Isn't K&N filter oil purple?

Reddish flakes in the bowls are usually from rust and dried fuel deposits.
Does your fuel tank have rust?

Electrical... 
Fully charge your battery disconnected from the bike, and let it rest 2 hours.   The voltage should be 12.6 v minimum, assuming the battery is at 70-ish degrees.  Anyway, measure and report.

Connect the battery to the bike and kick start the motor.  Electric starters draw 150 amps, depleting the battery.

Now measure the battery voltage at idle, 2000, 3000, 4000, and 5000 RPM.  It is handy to have those same set of numbers with the headlight off or the headlight fuse removed.

Higher wattage headlights, 3 ohm coils, etc., can make the RPM where the battery starts charging, higher, even with a good charging system.

Cheers,

The readings with the headlight:
2000 - 12.68
3000 - 13.14
4000 - 14.15
5000 - 13.94
I went to take the same readings with the headlight fuse out and got 12.69 @2000 rpm. It then started running very rough, LOUD and it was popping getting up to 3000 rpm. So loud that I released the throttle and it then immediately died. Anyone know a good shop in Nashville? What did I get myself into getting a motorcycle without getting a motorcycle mechanics certification or something? I'm not giving up, but.............

Can you remove the spark plugs and make note of the deposits you see on them?

Looks like your charging system is working.  :)

Cheers,
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Offline cb750fbomb

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Re: Help with stalling after warm up
« Reply #16 on: February 10, 2009, 10:33:37 AM »
I've tried a 16 and a 17 socket and neither seems to fit. The 16 is a spark plug specific socket and the 17 is really deep. What am I doing wrong here?
« Last Edit: February 10, 2009, 10:39:01 AM by cb750fbomb »
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Offline Duke McDukiedook

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Re: Help with stalling after warm up
« Reply #17 on: February 10, 2009, 10:40:54 AM »
If I remember right the spark plug socket is a deep 18mm, Honda makes a special spark plug tool for easy removal. Can be a bit of a pain with a standard socket and wrench, but once you do it a fews times it get easy, just gotta get the feel for it.
Have patience with it, you'll get it running fine with some help with the people on this board.
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Offline cb750fbomb

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Re: Help with stalling after warm up
« Reply #18 on: February 10, 2009, 10:57:04 AM »

[/quote]

Can you remove the spark plugs and make note of the deposits you see on them?

Looks like your charging system is working.  :)

Cheers,
[/quote]
I'm all over that when i get my hands on a deep 18mm socket.  :) Thanks a lot for the help :) I will take pics of the plugs when they're pulled. 
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Offline TwoTired

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Re: Help with stalling after warm up
« Reply #19 on: February 10, 2009, 11:01:04 AM »
Quote from: cb750fbomb on February 10, 2009, 10:33:37 AM
I've tried a 16 and a 17 socket and neither seems to fit. The 16 is a spark plug specific socket and the 17 is really deep. What am I doing wrong here?


The plugs require an 18mm socket.  The stock tool kit includes a spark plug tool that can dodge the obstacles in the spark plug access tunnel.
Beware installation.   Cross threading spark plugs is a hang your head and cry affair.

Cheers,
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Offline cb750fbomb

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Re: Help with stalling after warm up
« Reply #20 on: February 10, 2009, 11:01:56 AM »
Quote from: Dukiedook on February 10, 2009, 10:40:54 AM
If I remember right the spark plug socket is a deep 18mm, Honda makes a special spark plug tool for easy removal. Can be a bit of a pain with a standard socket and wrench, but once you do it a fews times it get easy, just gotta get the feel for it.
Have patience with it, you'll get it running fine with some help with the people on this board.
Thanks for that spark plug socket info and thanks for the encouragement  :) Thank god for hardware store chains with tons of tools  :D
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Offline cb750fbomb

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Re: Help with stalling after warm up
« Reply #21 on: February 10, 2009, 11:08:26 AM »


The plugs require an 18mm socket.  The stock tool kit includes a spark plug tool that can dodge the obstacles in the spark plug access tunnel.
Beware installation.   Cross threading spark plugs is a hang your head and cry affair.

Cheers,
[/quote]
Is it worth it to order one and wait for it to be shipped or just get a socket? A quick google finds a 12 mm Honda spark plug tool, but not an 18 mm.
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Offline TwoTired

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Re: Help with stalling after warm up
« Reply #22 on: February 10, 2009, 11:18:21 AM »
Some on this forum have stated they can get a thin walled socket to work ok.

I have several of the Honda ones.  So, I don't bother with straight walled sockets.
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Offline Duke McDukiedook

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Re: Help with stalling after warm up
« Reply #23 on: February 10, 2009, 11:20:35 AM »
I just use a deep 18 on mine.
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Offline cb750fbomb

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Re: Help with stalling after warm up
« Reply #24 on: February 10, 2009, 11:42:03 AM »
I ordered the Honda tool from Western Hills Honda. Terry was a lot friendlier than my local Honda guys. I wanted to get the whole tool set that comes with the bike, but it's discontinued. :( He found the wrench for me immediately though. It would be awfully cool to have the whole OEM tool set. I'm still going to get the 18 mm deep socket so I can get to work. ;D
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