DanielBlack
XS650 Junkie
I've been having a great time over the last two weeks as I become further acquainted with my 77D, mostly stock, Stella. After the first basic safety checks and oil change, etc. I put her quickly into her role as my daily ride.
Most days are 5-10mi, but the last week has given me a few longer commutes close to 20m each way. The longer ride with speeds of 50-65 achieved for a ten minute run have given me the opportunity to learn a whole lot more about her than my usual 35-40mph stop/start jaunt.
Via the Haynes manual, two conversations with MMM, various guides such as the famous Carb Guide, my colleague's general motorcycle knowledge and this forum, I have made a pretty good start at making her a more solid, reliable, and better handling, enjoyable daily commuter.
For example, I was concerned with the jarring vibrations I was feeling as I revved up to 3500-4000 and I held back from pushing it further. Having searched the forum and finding a thread about vibrations starting at 3100, I learned about the rpm range in which the connecting rod is in flux between tension and compression. That made sense. Another member explained that our bikes want to be up past 4K, 3500 and less is still lugging the motor. Sounds good. On my next ride I held my shift until I was at 5 or 6K. Better shifts. Cruising in one lower gear than I had been, 4500 smoothed things out. I found I was able to locate the vibe range as 3400-4500.
In addition to the bad vibes, a few other items are piquing my interest. A slight ringing I'm hearing toward the top of the motor. A misbalanced exhaust note, the right sounding weaker with a bit of clack and uneven gait.
I figured I would eventually need to clean and rebuild the carbs, but knew there were things to do first. Here's where I am:
Battery is good. Holds 12v+ with headlamp on for 10+ minutes. Stock alternator provides 14v @ ~3500rpm. All electrics work, but I haven't yet gone through and checked for solid, clean connections.
The Iridium B7 plugs that were in there had seen better days. Color looked decent, maybe a little dry, but the electrodes were eaten up. I put basic coppers in for the moment, but Iridiums are here on Monday. B6 for the city driving in a desert.
The tank interior looks good and clean, very little surface rust. I've been using Seafoam in the last couple of tanks. Fuel flows well through the existing inline filters. But the lines are mismatched in type and age and don't have any clips. The hose on the R petcock is loose and seeps. New line and filters arrive on Monday.
I found cam chain guide bits in the first oil change. I'll change it again soon when this particular odo hits 25000 miles. I'm hoping its just a piece of plastic or two, and no aluminum this time. I adjusted it tonight when I got home from a short commute. It's the model without the lock nut, but it seemed to be in spec from when I did it at the 1st service. The plunger pops out .5mm as each cylinder passes TDC.
I'll do the valves tomorrow again, this time pulling the plugs and using a wrench on the bolt to get a more accurate TDC rather than spinning the rear wheel.
Turning the motor in this way tonight, I checked the timing of the Boyer ignition. It was way off by about 10-15* going by the dot in the window. It was hard stop in one direction, and the paint dot method wanted it near full stop the other way. I'll put a timing light on it when I bring it in to the local motorcycle diy shop for rebuilding the rear end.. (Very excited about that! A lift, tools, shop supplies, owners' experience all for a flat rate.)
After the timing adjustment the idle sounded a lot smoother, and a quick carb sync by ear seemed to get it closer. I have all the parts for a DIY manometer ready to go, except the barbs which also arrive Monday.
She's idling rather evenly and smoothly now at ~1400, and the results of a little 1st & 2nd gear test up and down the block make me excited to take her out tomorrow for a longer run after the valve adjust. I'm wondering how 3400-4500 will feel now. Then again on Monday after the manometer sync.
Tonight's timing and cam chain tension adjustments seem to have diminished the ringing up top, too. Maybe located around the cam shaft? I'll put a screwdriver stethoscope to it tomorrow.
We're getting there.
Most days are 5-10mi, but the last week has given me a few longer commutes close to 20m each way. The longer ride with speeds of 50-65 achieved for a ten minute run have given me the opportunity to learn a whole lot more about her than my usual 35-40mph stop/start jaunt.
Via the Haynes manual, two conversations with MMM, various guides such as the famous Carb Guide, my colleague's general motorcycle knowledge and this forum, I have made a pretty good start at making her a more solid, reliable, and better handling, enjoyable daily commuter.
For example, I was concerned with the jarring vibrations I was feeling as I revved up to 3500-4000 and I held back from pushing it further. Having searched the forum and finding a thread about vibrations starting at 3100, I learned about the rpm range in which the connecting rod is in flux between tension and compression. That made sense. Another member explained that our bikes want to be up past 4K, 3500 and less is still lugging the motor. Sounds good. On my next ride I held my shift until I was at 5 or 6K. Better shifts. Cruising in one lower gear than I had been, 4500 smoothed things out. I found I was able to locate the vibe range as 3400-4500.
In addition to the bad vibes, a few other items are piquing my interest. A slight ringing I'm hearing toward the top of the motor. A misbalanced exhaust note, the right sounding weaker with a bit of clack and uneven gait.
I figured I would eventually need to clean and rebuild the carbs, but knew there were things to do first. Here's where I am:
Battery is good. Holds 12v+ with headlamp on for 10+ minutes. Stock alternator provides 14v @ ~3500rpm. All electrics work, but I haven't yet gone through and checked for solid, clean connections.
The Iridium B7 plugs that were in there had seen better days. Color looked decent, maybe a little dry, but the electrodes were eaten up. I put basic coppers in for the moment, but Iridiums are here on Monday. B6 for the city driving in a desert.
The tank interior looks good and clean, very little surface rust. I've been using Seafoam in the last couple of tanks. Fuel flows well through the existing inline filters. But the lines are mismatched in type and age and don't have any clips. The hose on the R petcock is loose and seeps. New line and filters arrive on Monday.
I found cam chain guide bits in the first oil change. I'll change it again soon when this particular odo hits 25000 miles. I'm hoping its just a piece of plastic or two, and no aluminum this time. I adjusted it tonight when I got home from a short commute. It's the model without the lock nut, but it seemed to be in spec from when I did it at the 1st service. The plunger pops out .5mm as each cylinder passes TDC.
I'll do the valves tomorrow again, this time pulling the plugs and using a wrench on the bolt to get a more accurate TDC rather than spinning the rear wheel.
Turning the motor in this way tonight, I checked the timing of the Boyer ignition. It was way off by about 10-15* going by the dot in the window. It was hard stop in one direction, and the paint dot method wanted it near full stop the other way. I'll put a timing light on it when I bring it in to the local motorcycle diy shop for rebuilding the rear end.. (Very excited about that! A lift, tools, shop supplies, owners' experience all for a flat rate.)
After the timing adjustment the idle sounded a lot smoother, and a quick carb sync by ear seemed to get it closer. I have all the parts for a DIY manometer ready to go, except the barbs which also arrive Monday.
She's idling rather evenly and smoothly now at ~1400, and the results of a little 1st & 2nd gear test up and down the block make me excited to take her out tomorrow for a longer run after the valve adjust. I'm wondering how 3400-4500 will feel now. Then again on Monday after the manometer sync.
Tonight's timing and cam chain tension adjustments seem to have diminished the ringing up top, too. Maybe located around the cam shaft? I'll put a screwdriver stethoscope to it tomorrow.
We're getting there.
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