Yamaha XS650 help needed

Yamaha XS650 help needed

Hi all,

I have a 1980 XS 650 sidecar rig in need of some diagnostic expertise.
Cutting to the case.... . it runs at idle, but will not rev beyond idle. It
just falls flat on its face. Burbles, pops, spits. The problem started
about 5 miles after filling the tank. Cleared up briefly, than reverted back
to the not running above idle. I drained the tank and put in fresh gas. I
pulled the carbs X2 and cleaned them to no avail. I replaced the CDI unit
suspecting there was a problem with the ignition not advancing. I have had a
CDI unit puke before causing intermittent problems. . I can pull either
plug wire and the revs drop, from idle, the same amount. What ever the
problem is, it effects both cylinders equally. I see a strong spark at the
plug at idle, and it weakens as I attempt to rev the engine. I have cleaned
the plugs and tried a fresh battery. Actually, I run it off a car battery
in the sidecar trunk. Coil, perhaps? Also, I do not think there is a
problem with the tank petcock. I tried running the bike with the petcock
set in the prime position. Any help much appreciated. I cannot afford to
take it to a shop, but I really would like to get the beast running again.
FYI, here is a link to pictures of the rig.
* webpages.charter . net /clickfam/pictures.htm

Thanks,

Ron
w w w .mondo-ron . com

Re: Yamaha XS650 help needed


"Ron" <mondo_ron@yahoo . com > wrote in message
news:XWtNh.2$KN3.0@newsfe03.lga...
> Hi all,
>
> I have a 1980 XS 650 sidecar rig in need of some diagnostic expertise.
> Cutting to the case.... . it runs at idle, but will not rev beyond idle. It
> just falls flat on its face. Burbles, pops, spits. The problem started
> about 5 miles after filling the tank. Cleared up briefly, than reverted
> back
> to the not running above idle. I drained the tank and put in fresh gas.
> I
> pulled the carbs X2 and cleaned them to no avail.

You could have petcock flow problems... verify
that fuel gushes out the petcocks when on. This
is not as simple as it sounds, since your bike (I
owned a '79) has vacuum-operated fuel. See
if the symptoms go away when you turn the
petcocks from Auto to On. My XS petcocks
ended up giving up the ghost when I ran
gasahol through them... had to glue up the
weep holes with epoxy and use them manually
from then on.

You could also have fuel passages or jets plugged...
the low-speed mixture needles may need to come
out. Did you find lots of grot in the fuel bowls?

Look for symptoms of rich or lean... the 'pop'
sounds lean, the 'spit' sounds rich... more research
is necessary.
__
Steve
.

Re: Yamaha XS650 help needed


"Stephen Cowell" <scowell@sbcglobal . net > wrote in message
news:GsyNh.1625$YL5.855@newssvr29.news.prodigy . net ...
>
> "Ron" <mondo_ron@yahoo . com > wrote in message
> news:XWtNh.2$KN3.0@newsfe03.lga...
>> Hi all,
>>
>> I have a 1980 XS 650 sidecar rig in need of some diagnostic expertise.
>> Cutting to the case.... . it runs at idle, but will not rev beyond idle.
>> It
>> just falls flat on its face. Burbles, pops, spits. The problem started
>> about 5 miles after filling the tank. Cleared up briefly, than reverted
>> back
>> to the not running above idle. I drained the tank and put in fresh gas.
>> I
>> pulled the carbs X2 and cleaned them to no avail.
>
> You could have petcock flow problems... verify
> that fuel gushes out the petcocks when on. This
> is not as simple as it sounds, since your bike (I
> owned a '79) has vacuum-operated fuel. See
> if the symptoms go away when you turn the
> petcocks from Auto to On. My XS petcocks
> ended up giving up the ghost when I ran
> gasahol through them... had to glue up the
> weep holes with epoxy and use them manually
> from then on.
>
> You could also have fuel passages or jets plugged...
> the low-speed mixture needles may need to come
> out. Did you find lots of grot in the fuel bowls?
>
> Look for symptoms of rich or lean... the 'pop'
> sounds lean, the 'spit' sounds rich... more research
> is necessary.
> __
> Steve

Hi Steve,

Yea, I ran the bike with the petcock on 'prime' and gas flowed freely. When
I pulled the carbs, I did not not see any junk in the bowls and I cleaned
the jets. The thing that makes me think it may be an electrical issue is
the fact that both cylinders seem to be equally effected and both carbs seem
to be getting gas. If one carb was junked up, I should still be able to rev
a bit above idle. But there again.......

Thanks!

Ron
w w w .mondo-ron . com

Re: Yamaha XS650 help needed


"Ron" <mondo_ron@yahoo . com > wrote in message
news:eHyNh.160$k_4.10@newsfe06.lga...
>
> "Stephen Cowell" <scowell@sbcglobal . net > wrote in message
> news:GsyNh.1625$YL5.855@newssvr29.news.prodigy . net ...
>>
>> "Ron" <mondo_ron@yahoo . com > wrote in message
>> news:XWtNh.2$KN3.0@newsfe03.lga...
>>> Hi all,
>>>
>>> I have a 1980 XS 650 sidecar rig in need of some diagnostic expertise.
>>> Cutting to the case.... . it runs at idle, but will not rev beyond idle.
>>> It
>>> just falls flat on its face. Burbles, pops, spits. The problem started
>>> about 5 miles after filling the tank. Cleared up briefly, than reverted
>>> back
>>> to the not running above idle. I drained the tank and put in fresh gas.
>>> I
>>> pulled the carbs X2 and cleaned them to no avail.
>>
>> You could have petcock flow problems... verify
>> that fuel gushes out the petcocks when on. This
>> is not as simple as it sounds, since your bike (I
>> owned a '79) has vacuum-operated fuel. See
>> if the symptoms go away when you turn the
>> petcocks from Auto to On. My XS petcocks
>> ended up giving up the ghost when I ran
>> gasahol through them... had to glue up the
>> weep holes with epoxy and use them manually
>> from then on.
>>
>> You could also have fuel passages or jets plugged...
>> the low-speed mixture needles may need to come
>> out. Did you find lots of grot in the fuel bowls?
>>
>> Look for symptoms of rich or lean... the 'pop'
>> sounds lean, the 'spit' sounds rich... more research
>> is necessary.
>> __
>> Steve
>
> Hi Steve,
>
> Yea, I ran the bike with the petcock on 'prime' and gas flowed freely.
> When I pulled the carbs, I did not not see any junk in the bowls and I
> cleaned the jets. The thing that makes me think it may be an electrical
> issue is the fact that both cylinders seem to be equally effected and both
> carbs seem to be getting gas. If one carb was junked up, I should still
> be able to rev a bit above idle. But there again.......

How do the plugs look? Got timing light?
Verify the centrifugal advance/points are OK...
check battery voltage. You may have done
the headlight switch mod... does it idle the
same with the headlight on? GL...
--
__
Steve
KI5YG
'06 FXDI
#0627
.

Re: Yamaha XS650 help needed


"Stephen Cowell" <scowell@sbcglobal . net > wrote in message
news:AyzNh.3135$Kd3.348@newssvr27.news.prodigy . net ...
>
> "Ron" <mondo_ron@yahoo . com > wrote in message
> news:eHyNh.160$k_4.10@newsfe06.lga...
>>
>> "Stephen Cowell" <scowell@sbcglobal . net > wrote in message
>> news:GsyNh.1625$YL5.855@newssvr29.news.prodigy . net ...
>>>
>>> "Ron" <mondo_ron@yahoo . com > wrote in message
>>> news:XWtNh.2$KN3.0@newsfe03.lga...
>>>> Hi all,
>>>>
>>>> I have a 1980 XS 650 sidecar rig in need of some diagnostic expertise.
>>>> Cutting to the case.... . it runs at idle, but will not rev beyond idle.
>>>> It
>>>> just falls flat on its face. Burbles, pops, spits. The problem
>>>> started
>>>> about 5 miles after filling the tank. Cleared up briefly, than reverted
>>>> back
>>>> to the not running above idle. I drained the tank and put in fresh
>>>> gas. I
>>>> pulled the carbs X2 and cleaned them to no avail.
>>>
>>> You could have petcock flow problems... verify
>>> that fuel gushes out the petcocks when on. This
>>> is not as simple as it sounds, since your bike (I
>>> owned a '79) has vacuum-operated fuel. See
>>> if the symptoms go away when you turn the
>>> petcocks from Auto to On. My XS petcocks
>>> ended up giving up the ghost when I ran
>>> gasahol through them... had to glue up the
>>> weep holes with epoxy and use them manually
>>> from then on.
>>>
>>> You could also have fuel passages or jets plugged...
>>> the low-speed mixture needles may need to come
>>> out. Did you find lots of grot in the fuel bowls?
>>>
>>> Look for symptoms of rich or lean... the 'pop'
>>> sounds lean, the 'spit' sounds rich... more research
>>> is necessary.
>>> __
>>> Steve
>>
>> Hi Steve,
>>
>> Yea, I ran the bike with the petcock on 'prime' and gas flowed freely.
>> When I pulled the carbs, I did not not see any junk in the bowls and I
>> cleaned the jets. The thing that makes me think it may be an electrical
>> issue is the fact that both cylinders seem to be equally effected and
>> both carbs seem to be getting gas. If one carb was junked up, I should
>> still be able to rev a bit above idle. But there again.......
>
> How do the plugs look? Got timing light?
> Verify the centrifugal advance/points are OK...
> check battery voltage. You may have done
> the headlight switch mod... does it idle the
> same with the headlight on? GL...
> --
> __
> Steve
> KI5YG
> '06 FXDI
> #0627

Hi Steve,

The plugs look good. First, I cleaned them. Later, I had one spare new
plug, and tried it, also. No points and condensor on the
bike.....electronic ignition (CDI)....replaced it X2 with used units....no
such thing as a new CDI, anymore. Lights are bright and the horn is loud. I
have an air horn as well as a bright running light on the sidecar. Tried a
known good car battery just recently, too.

Thanks!

Ron

Re: Yamaha XS650 help needed


"Ron" <mondo_ron@yahoo . com > wrote in message
news:XWtNh.2$KN3.0@newsfe03.lga...
> Hi all,
>
> I have a 1980 XS 650 sidecar rig in need of some diagnostic expertise.
> Cutting to the case.... . it runs at idle, but will not rev beyond idle.
> It
> just falls flat on its face. Burbles, pops, spits. The problem started
> about 5 miles after filling the tank. Cleared up briefly, than reverted
> back
> to the not running above idle. I drained the tank and put in fresh gas.
> I
> pulled the carbs X2 and cleaned them to no avail. I replaced the CDI
> unit
> suspecting there was a problem with the ignition not advancing. I have
> had a
> CDI unit puke before causing intermittent problems. . I can pull either
> plug wire and the revs drop, from idle, the same amount. What ever the
> problem is, it effects both cylinders equally. I see a strong spark at
> the
> plug at idle, and it weakens as I attempt to rev the engine. I have
> cleaned
> the plugs and tried a fresh battery. Actually, I run it off a car
> battery
> in the sidecar trunk. Coil, perhaps? Also, I do not think there is a
> problem with the tank petcock. I tried running the bike with the
> petcock
> set in the prime position. Any help much appreciated. I cannot afford
> to
> take it to a shop, but I really would like to get the beast running
> again.
> FYI, here is a link to pictures of the rig.
> * webpages.charter . net /clickfam/pictures.htm
>
I had an old van that sat in my driveway for a few years before I got
around to getting it ready to sell. It would hardly run above an idle
too. It turned out that all the rust that had accumulated in the exhaust
blew into the catalytic converter when I started it, plugging the exhaust.

Don't know how your exhaust could have plugged up.

Robert

Re: Yamaha XS650 help needed

On Mar 25, 7:29 am, "Ron" <mondo ...@yahoo . com > wrote:

> I have a 1980 XS 650 sidecar rig in need of some diagnostic expertise.

Have you talked to the folks at the Society of the 650?

* beaver.vinu.edu/650.htm

How about the XS650 discussion group?

* beaver.vinu.edu/650list.HTM

Sometimes a marque/model expert can be really valuable. Good luck!

Tim

Re: Yamaha XS650 help needed

try this site if you can't find a new part for your 650 these guys know
where they are or know what will work * w w w .650motorcycles . com
they have alot of people around the world and a a dealer that knows
where you can the new ignition parts for your bike ,and try these guys
too * w w w .yamatopdog . com they have original OEM and reproduction
stuff for the older Yamahas that you can't find anywhere ,they are
located in Bloomsburg ,PA they guys there are pretty cool they will try
to help you out best they can .
Good Luck and keep riding