running issue

Message
Author
bshannon_1
Rookie
Rookie
Posts: 4
Joined: Sat Aug 16, 2014 4:41 pm
Real Name: william shannon
Sex: Male
Years Riding: 34
My Motorcycle: 1983 honda cb650sc nighthawk

running issue

#1 Unread post by bshannon_1 »

I have an '83 Honda cb650sc nighthawk. I recently replaced the voltage rectifier with a new one and had the stator rebuilt. I aslo checked the battery and made sure it had a full charge on it. The battery is only a couple of months old. When I start the bike it runs fine at first but after a couple of minutes it shuts off as though one of the switches were turned to the off position even though they haven't been. After it quits the power is still on but when you depress the start button nothing happens. I then turn the ignition off and the kill switch to the off position. after a few minutes I power the bike back up hit the start button and the bike starts runs for a couple of minutes the shuts off again. Does anyone have an idea what the problem is, for I'm at my whits end. you can respond to my email address: [email protected]

GS_in_CO
Legendary 300
Legendary 300
Posts: 300
Joined: Thu Jun 27, 2013 2:10 pm
Real Name: Ron
Sex: Male
Years Riding: 34
My Motorcycle: 1988 BMW R100GS
Location: Ft. Collins, CO.

Re: running issue

#2 Unread post by GS_in_CO »

sounds like the battery isn't holding a charge. (but I'm not going to email the answer)
Ron

Current: 1988 BMW R100GS (the 'numberplate' model)

Past: 1987 Yamaha XT350
1983 Honda CB900F
1980 Honda XL185S
1979 Suzuki GS425E

User avatar
Johnj
Site Supporter - Platinum
Site Supporter - Platinum
Posts: 3806
Joined: Fri Nov 17, 2006 7:34 am
Real Name: Johnny Strabler
Sex: Male
Years Riding: 34
My Motorcycle: A Bolt of Lightning
Location: Kansas City KS

Re: running issue

#3 Unread post by Johnj »

"SOMETHING" is getting HOT and shutting down. Like a regulator or a rectifier. Try using your hand to see which is hot.
People say I'm stupid and apathetic. I don't know what that means, and I don't care.
Image
Always wear a helmet, eye protection, and protective clothing. Never ride under the influence of drugs or alcohol.

bshannon_1
Rookie
Rookie
Posts: 4
Joined: Sat Aug 16, 2014 4:41 pm
Real Name: william shannon
Sex: Male
Years Riding: 34
My Motorcycle: 1983 honda cb650sc nighthawk

Re: running issue

#4 Unread post by bshannon_1 »

No, the rectifier is not even warm and is brand new as well as the stator. Moreover, the bike will not run long enough to even get to operating temp.

GS_in_CO
Legendary 300
Legendary 300
Posts: 300
Joined: Thu Jun 27, 2013 2:10 pm
Real Name: Ron
Sex: Male
Years Riding: 34
My Motorcycle: 1988 BMW R100GS
Location: Ft. Collins, CO.

Re: running issue

#5 Unread post by GS_in_CO »

Are you charging the battery before attempting to run the bike?
Are you monitoring the voltage on the battery as it runs?

Since you replaced voltage regulation/generating parts before this problem..... chances are real good that the two are related.

I should add that the battery could have been damaged by leaving it discharged for several months if the reason it sat idle was because of the charging system not working. lead-acid batteries really, really, really don't take well to staying discharged.
Ron

Current: 1988 BMW R100GS (the 'numberplate' model)

Past: 1987 Yamaha XT350
1983 Honda CB900F
1980 Honda XL185S
1979 Suzuki GS425E

bshannon_1
Rookie
Rookie
Posts: 4
Joined: Sat Aug 16, 2014 4:41 pm
Real Name: william shannon
Sex: Male
Years Riding: 34
My Motorcycle: 1983 honda cb650sc nighthawk

Re: running issue

#6 Unread post by bshannon_1 »

No, I've kept the battery charged, and I'm not sure if it is getting charged due to the fact that the bike will not stay running long enough to test it. It will only run for A minute or two. However, I feel that the battery has continued to keep a charge since it has not been drained.

User avatar
BRUMBEAR
Legendary 1000
Legendary 1000
Posts: 1227
Joined: Sat Feb 04, 2006 3:27 am
Real Name: Dave
Sex: Male
Years Riding: 40
My Motorcycle: 2009 Buell 1125 CR
Location: in limbo

Re: running issue

#7 Unread post by BRUMBEAR »

hmmm that sounds like it could be the new stator heating up and shorting but the main power fuse should blow you don't have one of the circuit breaker style fuses in there do ya?
there aint nothin like it

GS_in_CO
Legendary 300
Legendary 300
Posts: 300
Joined: Thu Jun 27, 2013 2:10 pm
Real Name: Ron
Sex: Male
Years Riding: 34
My Motorcycle: 1988 BMW R100GS
Location: Ft. Collins, CO.

Re: running issue

#8 Unread post by GS_in_CO »

Well - there's still the classic plugged fuel tank vent so that the fuel isn't flowing quickly enough into the carbs....
Or plugged petcock strainer, or contaminated fuel in the carb bowl so there isn't enough good fuel to run for long....
Ron

Current: 1988 BMW R100GS (the 'numberplate' model)

Past: 1987 Yamaha XT350
1983 Honda CB900F
1980 Honda XL185S
1979 Suzuki GS425E

User avatar
dr_bar
Site Supporter - Diamond
Site Supporter - Diamond
Posts: 4532
Joined: Mon May 23, 2005 4:37 am
Real Name: Doug
Sex: Male
Years Riding: 44
My Motorcycle: 2007 Yamaha Royal Star Venture
Location: Surrey BC, Canada

Re: running issue

#9 Unread post by dr_bar »

I'm going to say it has to do with the rectifier/ regulator. Possibly faulty, it sounds like there is no charge going to the battery and the engine is running off the battery instead of the stator, which would be why the battery drops dead so quick...
~~~~~~~~~~~~~~~~~~~~~~~~~~~

"Four wheels move the body.
Two wheels move the soul!"

GS_in_CO
Legendary 300
Legendary 300
Posts: 300
Joined: Thu Jun 27, 2013 2:10 pm
Real Name: Ron
Sex: Male
Years Riding: 34
My Motorcycle: 1988 BMW R100GS
Location: Ft. Collins, CO.

Re: running issue

#10 Unread post by GS_in_CO »

dr_bar wrote:I'm going to say it has to do with the rectifier/ regulator. Possibly faulty, it sounds like there is no charge going to the battery and the engine is running off the battery instead of the stator, which would be why the battery drops dead so quick...
The duration of the run seems too short for this to be the case unless the battery has no capacity.
(BTW- the charging system doesn't carry the load when at idle on most bikes - the battery does.)

But a way to double-check it - other than using the correct tool for the job (a voltmeter) - might be to disconnect the headlight so as to reduce the electrical load while running.


On the other hand- I once stored my XT350 with an additional Marvel Mystery Oil in the gasoline.
During the storage period the oil separated and went to the bottom of the tank. At restart time it would only run a short time. There was oil instead of gas in the carb bowl. Draining the bowl fixed the problem. That's probably not the case here but odd things can happen.
Ron

Current: 1988 BMW R100GS (the 'numberplate' model)

Past: 1987 Yamaha XT350
1983 Honda CB900F
1980 Honda XL185S
1979 Suzuki GS425E

Post Reply