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XS 650 downshifting issues



Hi group,

Just recently, and not too long after an oil change, I began to experience
some difficulty downshifting my 1980 Yamaha XS650. Upshifts are great,
Item #4 is probably an eccentric stud used for adjusting the weird mechanism
that grabs the end of the shifter drum and turns it. It would be on the
clutch side of the engine if it's
like other Yamahas that I owned.

The shifter drum and shifter forks are inside the cases, the mickey mouse
stuff is behind the clutch cover.

Sometimes the circlips that locate the freewheeling gears wear out, and when
you try to shift, the wheel gear just gets pushed away from the dogs on the
sliding pinion gear.

Also, the dogs will get rounded off. especially on 2nd gear, so the gear has
to be replaced or the dogs undercut.

smooth as butter. When
going down the gears, though, I sometimes have to nudge the shift lever
twice. First nudge may feel like something is not 'engaging' so to speak,
but the second nudge works just fine, with out regard to what gear I am
moving to, be it 5th to 4th, or 4th to 3rd.........etc. There is no undue
effort on the lever, either. Seems to 'maybe' get a bit better as the
engine warms
up, but the issue does not go away. I checked the oil level and verified I
used the 'correct' viscosity(Yamalube 20W-40....will probably start using
Castrol 20W-50); I've heard motorcycle gearboxes can be a bit sensitive to
oil levels, etc. I also checked clutch cable adjustments. Seems OK. Any
advice much appreciated. Please tell me there will be no major surgery
involved...............................
Is the final drive chain adjusted too tight? Check there's still *some*
slack when sitting on the bike.
An over-tight chain can cause these problems plus difficulties in finding
neutral.
Did you adjust around the same time as the oil change?

Otherwise it's likely to be a problem with the internal selector mechanism.

How many miles has the bike done?
Outstanding!

Ron

Do you know it's history?


Ron
http://webpages.charter.net/clickfam/pictures.htm pics of the mad beast