funky
XS650 Junkie
i love that red bike ...I have been looking for an owners manual and a service booklet for my bike but never been able to find one If anyone can help please PM me i have a 1981 special 3L1-029589
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I finally pulled the trigger, it’s not perfect but it’s mine. How’d I do?
- Thread starter Srawl
- Start date
I've never had any screwdrivers last long enough to justify spending much on them. I got a Craftsman bit holder screwdriver at a pawn shop and use various bits. I have some jis bits for smaller more sensitive screws. One time I picked up a phillips bit laying in a parking lot and out of curiosity filed the end flat since I'd read it was a way to make a substitute jis. That is the bit I've used for almost everything for the last half a decade 
Grips nice. .
Grips nice. .
Srawl
XS650 Enthusiast
So I pulled my spark plugs and this is what I’m looking at. They’re black and a little wet. How bad is this?
What I found online, which in my very non expert opinion looks like the first picture, says excessive choking (possible but wouldn’t be my first thought), ignition system troubles (immediately seemed likely due to not easy to start), or oil getting past the piston rings and valve guides (sounds the worst).
What I found online, which in my very non expert opinion looks like the first picture, says excessive choking (possible but wouldn’t be my first thought), ignition system troubles (immediately seemed likely due to not easy to start), or oil getting past the piston rings and valve guides (sounds the worst).
It could be bad but may not be. When you use the choke, it blackens the plugs. Multiple starts using the choke in your driveway or garage will eventually get the plugs looking like that. A bit of a ride, several miles at least, is needed after starting with the choke to burn the plugs clean again. Make sure the plugs are the correct heat range too (#7). Colder plugs will burn darker and foul easier.
funky
XS650 Junkie
Definatley fouling there The trouble is with fueling issues and fouling of plugs you have to start at the begging and finish at the end
..... What i mean is everything has to be right you will never get a good plug if your getting blow by or you carbs are dirty or worn
timming,,, valve lash ,,,tensioner,, all come into play at some point.
those plugs are clearly coated in burnt oil .
first Compression test and leakage test first. strip carbs and clean clean clean, replace anything that is old or worn or broken .....Do not mess with jets at the moment just clean them.
That oil can only come from worn rings,,, head gasket blown normally timimg chain well area ,,,, or valve stem oil seals.
Process of elimination dont cut corners.
All the best
Funky
The trouble is with fueling issues and fouling of plugs you have to start at the begging and finish at the end ..... What i mean is everything has to be right you will never get a good plug if your getting blow by or you carbs are dirty or worn timming,,, valve lash ,,,tensioner,, all come into play at some point.those plugs are clearly coated in burnt oil .
first Compression test and leakage test first. strip carbs and clean clean clean, replace anything that is old or worn or broken .....Do not mess with jets at the moment just clean them.
That oil can only come from worn rings,,, head gasket blown normally timimg chain well area ,,,, or valve stem oil seals.
Process of elimination dont cut corners.
All the best
Funky
funky
XS650 Junkie
Oh what ever happens get rid of those cone filters on the carbs there trouble
Srawl
XS650 Enthusiast
I have the boxes (I believe factory) with similar pleated but more oval filters I will be putting on.
Are these good to use?
Last edited:
Srawl
XS650 Enthusiast
Which bike is yours in pics 1-6? We have a history with '77 owners here
Lol, that seems to be causing some confusion, it is the red one. I have removed those other pics to avoid confusion in the future.
Srawl
XS650 Enthusiast
Ok, I have some updates.
Here is a brief rundown of the issues I’m having and what I’ve done so far:
I’ve replaced the spark plugs, wires, and caps. I drained the old (and very yellow) gas and replaced it with ethanol free, cleaned out the rusty tank, cleaned the petcocks. Compression is about 158 on both cylinders.
Cleaned out float bowl, replaced jets to factory settings, put factory air boxes on with what appear to be k&n style pleated filters, and put in a new battery.
Checked cam chain tension, cleaned and adjusted points, set timing.
I will be checking/adjusting the valves tonight and looking into how to adjust check/adjust the floats.
When I get on the highway, I always die about a mile or two down the road (a minute or two). It starts up fine after (kick only, electric start cranks but won’t start the bike) but will die within a couple miles at highway speed. I drove around a rural neighborhood averaging 35-45 mph for about 30 minutes and at about the 25 minute mark had to slow fast for some deer and it died but restarted after downshifting and releasing the clutch. It then Died again once more after that after stopping, but kicked on fine. Up to that point it ran perfect.
I think some of the dying while stopping issues may be coming from the clutch cable or something related. It is very tight and when on the center stand it will shift through the gears fine or idle in 1st but sometimes it wants die when it’s on the ground and the clutch pulled. I don’t think it’s fully engaging and going too slow for whatever gear is killing it. I also can be next to impossible to shift into neutral without reaching down and pulling it up after it has been ridden a while.
On the highway I think the problem may be related to the vent hole/seal. The seal is about shot (anyone got a line on a good replacement? I guess the repros are junk) and the vent hole was caked closed and after about 30 minutes of messing with it I got a lot of that old rotted filter out. I haven’t ridden it since but air now passes through it so we’ll see. I read about using scotch bright as a filter but don’t really know how that is supposed to work.
That’s about it for now, I do think the carbs probably need synchronized.
Feel free to share your opinions or advice.
Here are some pictures of new plugs I put in with approximately 30 miles on them:
Left:
I also noticed the left side exhaust pops a little bit, the right sounds smoother.
Right:
Here is a brief rundown of the issues I’m having and what I’ve done so far:
I’ve replaced the spark plugs, wires, and caps. I drained the old (and very yellow) gas and replaced it with ethanol free, cleaned out the rusty tank, cleaned the petcocks. Compression is about 158 on both cylinders.
Cleaned out float bowl, replaced jets to factory settings, put factory air boxes on with what appear to be k&n style pleated filters, and put in a new battery.
Checked cam chain tension, cleaned and adjusted points, set timing.
I will be checking/adjusting the valves tonight and looking into how to adjust check/adjust the floats.
When I get on the highway, I always die about a mile or two down the road (a minute or two). It starts up fine after (kick only, electric start cranks but won’t start the bike) but will die within a couple miles at highway speed. I drove around a rural neighborhood averaging 35-45 mph for about 30 minutes and at about the 25 minute mark had to slow fast for some deer and it died but restarted after downshifting and releasing the clutch. It then Died again once more after that after stopping, but kicked on fine. Up to that point it ran perfect.
I think some of the dying while stopping issues may be coming from the clutch cable or something related. It is very tight and when on the center stand it will shift through the gears fine or idle in 1st but sometimes it wants die when it’s on the ground and the clutch pulled. I don’t think it’s fully engaging and going too slow for whatever gear is killing it. I also can be next to impossible to shift into neutral without reaching down and pulling it up after it has been ridden a while.
On the highway I think the problem may be related to the vent hole/seal. The seal is about shot (anyone got a line on a good replacement? I guess the repros are junk) and the vent hole was caked closed and after about 30 minutes of messing with it I got a lot of that old rotted filter out. I haven’t ridden it since but air now passes through it so we’ll see. I read about using scotch bright as a filter but don’t really know how that is supposed to work.
That’s about it for now, I do think the carbs probably need synchronized.
Feel free to share your opinions or advice.
Here are some pictures of new plugs I put in with approximately 30 miles on them:
Left:
I also noticed the left side exhaust pops a little bit, the right sounds smoother.
Right:
Last edited:
Sounds like progress SRawl - well done!
The popping on the left could be related to an exhaust leak on that side or possibly, the LH carb is a bit too lean.
The popping on the left could be related to an exhaust leak on that side or possibly, the LH carb is a bit too lean.
Tomterrific
XS650 Junkie
You hAve dirt blocking the idle jet in the left carb. Pull out the mixgure adjusting screw and spray in carb cleaner. Stick the little red tube right in the hole and give a short blast. Wait a bit and blast some more. The dirt should be blasted into the float bowl. This is the quick and easy method I came up with. The alternative is tearing into your carb.
Tom
Tom
Srawl
XS650 Enthusiast
I’ll give that a shot, I’m guessing you’re speaking from experience but what exactly tells you that’s the problem?
Actually a rather common thing, statistically. It's a cheap/quick fix, or diagnostic. My favorite kind. Here's a reverse-flush project for you:
http://www.xs650.com/threads/revers...bs38-carburetor-pilot-circuit-idle-jet.42002/
http://www.xs650.com/threads/revers...bs38-carburetor-pilot-circuit-idle-jet.42002/
Srawl
XS650 Enthusiast
Took the bike out after all that and it ran great, didn’t even sputter once. I think I have the major issues figured out.
I tried that carb cleaner in the mix hole and set the needles at two turns out after.
Here’s what the plugs look like after the ride.
Right:
Left:
I tried that carb cleaner in the mix hole and set the needles at two turns out after.
Here’s what the plugs look like after the ride.
Right:
Left:
