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My 60th birthday present
- Thread starter Mailman
- Start date
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- Tags
- 1977 xs 650d chain and sprockets clutch pushrod seal cranckcase seal new front master cylinder pamco e-advance pamco ultimate high output ignition rebuild brake caliper rebuild brakes rebuilt carburetors replace clutch solid state rectifier stainless steel braid front brake line starter gear fix steering head bearings vr-115 regulator
OK dammit, I'm comin' over.
Let's get this danged bike sorted out Bob.
Let's get this danged bike sorted out Bob.
Alright! Pete C'mon down! I'll fire up the barbie and put some beer on ice. Maybe we'll eventually get around to looking at the bike! Haha
....there is one other possibility Bob.....
Let me preface by saying that my Lucille starts very predictably on the first or second push of the button (if I remember to push the enrichener lever - oh yeah, and turn on the danged petcocks) and she idles between 1200 and 1600 rpm according to her mood. She backfires softly when I decelerate and occasionally a cylinder will drop out for a moment or two on cold mornings. If I ride the he!! out of her, she gets about 48 MPG and if I baby her, she gets about 51 MPG, so one might think that she has a few tuning problems.
...but she is, afterall, a 41 year old motorcycle with what can only be seen as a very primitive set of carburetors. She has no O2 sensor, no TPS, no MAP - no engine electronics or monitoring at all. Heck - she doesn't even have an oil pressure sensor.
I wonder if we're not being perhaps just a bit too picky about how these old bikes run....
My 2007 Honda ST1300 has closed loop EFI and she starts and runs EXACTLY the same - every single time I push the button (the ST doesn't even have a kick starter). The mileage never varies and she produces the same power rain or shine, night or day - no matter what.
Anyhow, I have decided that my dear old Lucille runs as well as she's going to, and I'm happy.
BTW - I am not, for a moment, suggesting that we give up on troubleshooting or correcting obvious flaws like fuel or oil leaks etc - or the type of air leak that Mailman tracked down and fixed so effectively last week.
However, as I recall it, back in 1978, my three year old, 6000 mile 1975 XS650B backfired a little, the odd time. As for odd occurrences, I do recall one very tense night ride from Sault Ste. Marie to Wawa, Ontario (truly a desolate 130 mile stretch of wilderness road) when the B-model simply quit for a few seconds for no apparent reason. I'll never forget that gut wrenching feeling of silence and NO power while my speed dropped from 60 down to about 10 mph.... But the bike picked up just before I pulled off the road in the dark at 1:45 AM, 50 miles from any town, and I made it to my destination (and very horney girlfriend
) just fine.
When I arrived in Wawa (after some activities which will not further be described) I checked the bike over thoroughly, but never did figure out what happened to cause her to cut-out in the middle of nowhere like that. She did the same damned thing several more times over the next few years, but needless to say - she never did it in daylight, nor did she ever do it when situated less than 100 km from a town. I did some very long trips on my B-model, and she always got me there - but there was always a bit of...adventure in the trip.
Anyhow, I would guess that nowadays, our XS650s are seldom used for really long haul trips - but the older owners can, I am sure, confirm that they are quite capable of such excursions. The key point is, these are old bikes and they really do use pretty primitive technology - so, I am pretty relaxed about the level of perfection I expect.
Pete
Let me preface by saying that my Lucille starts very predictably on the first or second push of the button (if I remember to push the enrichener lever - oh yeah, and turn on the danged petcocks) and she idles between 1200 and 1600 rpm according to her mood. She backfires softly when I decelerate and occasionally a cylinder will drop out for a moment or two on cold mornings. If I ride the he!! out of her, she gets about 48 MPG and if I baby her, she gets about 51 MPG, so one might think that she has a few tuning problems.
...but she is, afterall, a 41 year old motorcycle with what can only be seen as a very primitive set of carburetors. She has no O2 sensor, no TPS, no MAP - no engine electronics or monitoring at all. Heck - she doesn't even have an oil pressure sensor.
I wonder if we're not being perhaps just a bit too picky about how these old bikes run....
My 2007 Honda ST1300 has closed loop EFI and she starts and runs EXACTLY the same - every single time I push the button (the ST doesn't even have a kick starter). The mileage never varies and she produces the same power rain or shine, night or day - no matter what.
Anyhow, I have decided that my dear old Lucille runs as well as she's going to, and I'm happy.
BTW - I am not, for a moment, suggesting that we give up on troubleshooting or correcting obvious flaws like fuel or oil leaks etc - or the type of air leak that Mailman tracked down and fixed so effectively last week.
However, as I recall it, back in 1978, my three year old, 6000 mile 1975 XS650B backfired a little, the odd time. As for odd occurrences, I do recall one very tense night ride from Sault Ste. Marie to Wawa, Ontario (truly a desolate 130 mile stretch of wilderness road) when the B-model simply quit for a few seconds for no apparent reason. I'll never forget that gut wrenching feeling of silence and NO power while my speed dropped from 60 down to about 10 mph.... But the bike picked up just before I pulled off the road in the dark at 1:45 AM, 50 miles from any town, and I made it to my destination (and very horney girlfriend
) just fine. When I arrived in Wawa (after some activities which will not further be described) I checked the bike over thoroughly, but never did figure out what happened to cause her to cut-out in the middle of nowhere like that. She did the same damned thing several more times over the next few years, but needless to say - she never did it in daylight, nor did she ever do it when situated less than 100 km from a town. I did some very long trips on my B-model, and she always got me there - but there was always a bit of...adventure in the trip.
Anyhow, I would guess that nowadays, our XS650s are seldom used for really long haul trips - but the older owners can, I am sure, confirm that they are quite capable of such excursions. The key point is, these are old bikes and they really do use pretty primitive technology - so, I am pretty relaxed about the level of perfection I expect.
Pete
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queenslegs
XS650 Addict
I couldn't agree more Pete. I've still got a bit of an oil leak, bit of a hanging idle, but I'm OK with that atm. I ride the bike, it's awesome!
Oh man I'd be happy just to have it run as good as I had it running before. It ran so nice, and started easily. It ran just like a '70s bike should.
But the last time I tried to start it , it wouldn't run at all.
I'll figure it out. It's not rocket science. Haha
But the last time I tried to start it , it wouldn't run at all.
I'll figure it out. It's not rocket science. Haha
My (unsolicited) advice...once you get it running, just stop messing with it and enjoy it.
That's actually a good sign. Assuming that your work has been confined to the carbs, that would be where the problem(s) lie. I'm sure you'll get it licked.
Here's a diagnostics flowchart to hang on the wall:
Something interesting happened to me with regard to a leaky float recently. When I shook it, no sound of internal fuel but when I rotated them slowly one got wet. Hairline crack that wasn't noticeable to the naked eye.
Probably would have shown up if I submerged looking for air bubbles but didn't bother once I saw the wet.
Good luck, you'll get em figured out.
Happy 4th.
Yes, this is an old bike and the design was relatively old even when it was new. They can be made to run well but may not run totally smooth and be well behaved 100% of the time. I still get an occasional backfire through the carbs when starting, usually if the bike is in that "gray" area somewhere between hot and cold. My idle is a little off. It doesn't wander or hang high, or stall, but it's just not really smooth. If you stand behind the bike and listen to the pipes, the right side is a nice steady bap, bap, bap, the left side not so much. The left sounds like it has an occasional minor misfire or stumble. It doesn't stall the bike or anything, it's just not smooth like the right side. It's always been like this, with the original points and now with a Pamco, with the original coils and 2 different aftermarket dual output coils, with 3 different sets of carbs I've tried. I've pretty much come to the conclusion that's just the way it idles. There's no fixing it it seems, but there probably is nothing to fix. It's just the way it is, one of the machine's "quirks". The bike runs quite well otherwise, no break-up or misfires throughout the RPM range, no plug fouling.
I have learned to quit declaring victory over a problem, as soon as I do it just bites me in the ass and makes me look like a dope. So, I am declaring cautious optimism!
The carbs are back together, I set all the adjustments to factory spec. Put them back on the bike and hooked everything up and fired that puppy up. Here's a little video.
When it fired up it was still running rough, coughing, reluctant to idle, but I got to idle well enough to check my timing and was surprised to see that my Pamco ignition was off a little, just outside the F marks, so I loosened up the timing plate and reset it, and it ran better, but the left cylinder was still coughing. So one side at a time I adjusted the air mixture screws, then back and forth a couple times and before you know it , it smoothed right out.
Throttle doesn't seem to be hanging up anymore. I haven't had it out for a ride yet because it's 111 degrees out right now and it's just not much fun. But next weekend early.
I'll let you know how it goes.
Here's to cautious optimists everywhere!
By the way Robin as I said, we are persistent,
We keep swinging until we wear 'em down.
Keep swinging buddy you're almost there.
Until next time
Bob
The carbs are back together, I set all the adjustments to factory spec. Put them back on the bike and hooked everything up and fired that puppy up. Here's a little video.
When it fired up it was still running rough, coughing, reluctant to idle, but I got to idle well enough to check my timing and was surprised to see that my Pamco ignition was off a little, just outside the F marks, so I loosened up the timing plate and reset it, and it ran better, but the left cylinder was still coughing. So one side at a time I adjusted the air mixture screws, then back and forth a couple times and before you know it , it smoothed right out.
Throttle doesn't seem to be hanging up anymore. I haven't had it out for a ride yet because it's 111 degrees out right now and it's just not much fun. But next weekend early.
I'll let you know how it goes.
Here's to cautious optimists everywhere!
By the way Robin as I said, we are persistent,
We keep swinging until we wear 'em down.
Keep swinging buddy you're almost there.
Until next time
Bob
WAY TO G........ooooppps, I will say this in a hushed, sedate, reserved manner so as to not bring that posting Murphy around again.
That is maybe, potentially, perhaps, positive news.
That is maybe, potentially, perhaps, positive news.
A couple of notes for those of you that are more detail oriented. I want to talk about my shim. My little handmade shim that nobody likes.
The whole reason for making it was to try to keep the butterfly from wearing into the throttle body.
2M said he thought it looked too thick. 5Twins suggested removing it entirely. When these guys talk I certainly listen. So when I had it apart this last time , I left it out. I had both carburetors assembled individually and bolted together with all the linkages in place ready to install. Then I started working the throttle, really looking at the action, specifically the butterfly in the worn carburetor and what I noticed was that, without the shim, even though the butterfly was centered perfectly in the bore when the throttle was shut, as soon as I opened the throttle the side pressure from the spring would cause the butterfly to deflect into the worn groove inside the body of the carburetor.
Also note, that I did not install the butterfly until I had the spring in place so that I would be centering the butterfly plate under loaded conditions.
What I wound up doing was thinning down my shim to about half of its original thickness using a Dremel and re installing it. After doing so and re assembling everything. I again checked the throttle action and the butterfly plate no longer deflects into the worn groove and it is perfectly centered in the bore.
On another note. The last time I had the carburetors off, I tried to kinda do a quickly clean without completely tearing them down. I wouldn't do that again. I think the only way to do it right is to completely dis assemble and be thorough about it.
And one other thought. I really thought that an electronic ignition was " Set it and forget it" but I'm glad I checked it because it was no longer on the money and required some fiddling.
Pete, I guess it wasn't haunted, but you just might have scared it into compliance when you threatened to come down here and straighten it out.
The whole reason for making it was to try to keep the butterfly from wearing into the throttle body.
2M said he thought it looked too thick. 5Twins suggested removing it entirely. When these guys talk I certainly listen. So when I had it apart this last time , I left it out. I had both carburetors assembled individually and bolted together with all the linkages in place ready to install. Then I started working the throttle, really looking at the action, specifically the butterfly in the worn carburetor and what I noticed was that, without the shim, even though the butterfly was centered perfectly in the bore when the throttle was shut, as soon as I opened the throttle the side pressure from the spring would cause the butterfly to deflect into the worn groove inside the body of the carburetor.
Also note, that I did not install the butterfly until I had the spring in place so that I would be centering the butterfly plate under loaded conditions.
What I wound up doing was thinning down my shim to about half of its original thickness using a Dremel and re installing it. After doing so and re assembling everything. I again checked the throttle action and the butterfly plate no longer deflects into the worn groove and it is perfectly centered in the bore.
On another note. The last time I had the carburetors off, I tried to kinda do a quickly clean without completely tearing them down. I wouldn't do that again. I think the only way to do it right is to completely dis assemble and be thorough about it.
And one other thought. I really thought that an electronic ignition was " Set it and forget it" but I'm glad I checked it because it was no longer on the money and required some fiddling.
Pete, I guess it wasn't haunted, but you just might have scared it into compliance when you threatened to come down here and straighten it out.
They say electronic ignitions are "set and forget" but it seems often times shortly after a fresh install, it needs a little tweak. I don't know what it is, maybe all the new parts settling in? With your hot climate you may also be re-visiting the setting to retard it slightly and eliminate minor pinging. I tweaked mine several times before I was happy with it. I run the idle timing over near the right (retarded) side of the range which puts the full advance just before it's slash mark. That turned out to be not such a bad thing. I think the bike actually runs a bit stronger like this, especially at higher RPMs and speeds.
Wow Bob - how do you get those engine cases so darned clean?
Great, Mailman, it runs! However, I'd expect the left side to be a bit rough, what with that scraping wear in there. Setting sync will be a challenge.
Now, THAT's significant.
IF the outer edge of the throttle shaft's bore is rough and uneven, the side of the nylon spacer there could've developed a gouge wear pattern, and upon initial rotation it would settle into a deeper seated position, allowing the shaft to slide outboard and the butterfly plate would gouge the side. Your washer fills over that roughness, stops this 'cam-out' movement.
On the same side of that carb you found that ultra-rough surface behind the enrichner.
What I'm thinking is that finish machining was skipped on that side of that carb.
That carb has probably been like that since new. The throttle bore's wear pattern sure looks like a lifetime of scraping.
Would love to see a crisp close-up of that throttle shaft's bore edge.
If you ever decide to get back into it, there's a simple way to straighten that edge. In the meantime, thinkin' on what would be a good way to fill-in the gouged bore...
Now, THAT's significant.
IF the outer edge of the throttle shaft's bore is rough and uneven, the side of the nylon spacer there could've developed a gouge wear pattern, and upon initial rotation it would settle into a deeper seated position, allowing the shaft to slide outboard and the butterfly plate would gouge the side. Your washer fills over that roughness, stops this 'cam-out' movement.
On the same side of that carb you found that ultra-rough surface behind the enrichner.
What I'm thinking is that finish machining was skipped on that side of that carb.
That carb has probably been like that since new. The throttle bore's wear pattern sure looks like a lifetime of scraping.
Would love to see a crisp close-up of that throttle shaft's bore edge.
If you ever decide to get back into it, there's a simple way to straighten that edge. In the meantime, thinkin' on what would be a good way to fill-in the gouged bore...
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Guess I musta missed this in the deluge of info while I was gone; Groove worn in the side of the bore???? You may get this thing running with that carb body, but idling well seems like a stretch using that carb body.
I probably have a set of decent 76-77 carbs for rebuilding.
ps XSJohn was a staunch advocate of slightly retarded timing for best operation. IIRC he also finagled head gasket thickness for cam timing reasons.
I probably have a set of decent 76-77 carbs for rebuilding.
ps XSJohn was a staunch advocate of slightly retarded timing for best operation. IIRC he also finagled head gasket thickness for cam timing reasons.
Gary there are photos of the wear in the body starting at post #731
So I went through about 6 sets of linked BS38s 76-77 and 78-79 sets, and shot up the bores. Here's some results
All but a set with 5K miles show at least a bit of wear on the LH side of the bore. Seems like the LH carb shows more wear, I note that carb has a much heavier return spring. perhaps that pulls the shaft left? I can certainly sympathise with you're trying to bush away that sideways "pressure"
All but a set with 5K miles show at least a bit of wear on the LH side of the bore. Seems like the LH carb shows more wear, I note that carb has a much heavier return spring. perhaps that pulls the shaft left? I can certainly sympathise with you're trying to bush away that sideways "pressure"
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Wow Gary! Thanks for all your effort on that. So I don't have some anomaly. That's really interesting.
Even with the damage done to my carburetor, it can be made to idle very steadily, but I have noticed that the left cylinder that has the damaged carb has a somewhat erratic firing. You can feel it when you put your hand to the end of the exhaust and you can hear it chuff and pop a little.
Even with the damage done to my carburetor, it can be made to idle very steadily, but I have noticed that the left cylinder that has the damaged carb has a somewhat erratic firing. You can feel it when you put your hand to the end of the exhaust and you can hear it chuff and pop a little.
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