Locking up

Aussie

Aussie

XS650 Enthusiast
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Took my xs650 to a show on weekend and won best custom and best in show,:D bike ran great :bike:. Come to go out today, started fine, shifted in to first moved about 2 foot and bike locked up solid :eek:( forward and backward ), shifted to neutral then back into fist and rode off, no probs. Came to a junction and whilst coasting to a stop I shifted to first and bang, :yikes: :wtf: bike locked up. Luckily I wasn't going at all fast. Shifted to neutral then back to first and pulled away. Rode home and parked up a little concerned. Have been riding for 30 years and not come across this before, but this is my first xs650. Anyone got any idea what the f*ck is going on here. I am at a loss. :banghead::confused::mad:
 
What does the chain and sprockets look like? Excessive wear? Something jammed up under the left side cover? When it "locks up" will it roll in neutral? How about with the clutch pulled in?
 
New chain and sprockets, nothin' jammed under cover. Feels like something jamming in the gear cogs maybe. Stripped side cover ,checked clutch rod, chain etc. Just taken it around the block and hasn't locked. Got back home and manoeuvring in garden it locked up again. But switch to neutral and back to first and its ok. ? . Only in first it does it too. It is a bit tricky to get it to shift to neutral now I find. You think it's in and "BANG" it slaps into first. So don't leave it in neutral whilst standing at moment. Wondering if it is a gear selector fork maybe. Also when I got the bike the flat part of dipstick was missing so am wondering if previous owner replaced it wrong and it has sheared off and floating around the gears somewhere and just moving into wrong place every now and then, but why only first.
 
pin in one of the shifter forks loose/broken .... going into two gears at once will lock it up outside of the nastiness of pulling the engine you can pull the lower case to check the forks and shifter drum without to much trouble
 
two gears at once is my guess too. Bike's way of sayin' don't get TOO proud?
 
First step would be to drain oil, both drainplugs, and pull sump cover. Filter oil, check drainplug magnets, check sump filter. Check side filter. Looking for metallic/magnetic bits.

Next would be to pull right cover and inspect kickstart gear/shaft. (1st gear is engaged by kickstart)

Last would be teardown, split case, look for bits, inspect trans/gears and shift forks.

Some pics (courtesy of punkscaler), and transmission parts list for reference:
 

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Another thing to check would be the shift shaft adjustment behind the clutch. Broken springs on the shift shaft.
Leo
 
UPDATE: When I drained the oil it was clean, magnets clean, filter clean. Small oil filter on side looks like the original fitted by Yamaha (looked well old and fukked) was full of shit, grease? bits of gasket glue and what looked like ally dust, like a paste almost. Nothing inside the cases or in the oil though.Took alternator cover off. Nothing amiss there. Took clutch cover off, clutch off ( plates look a bit thin, but not excessive ). That star cover thingy behind clutch is loose, the screw won't do up at all. Springs both look good. When put into neutral and cranking by hand on clutch drive shaft it will turn almost 360 degrees then lock.......
What do you think. I am going to have to split bottom case ain't I
 
There are two springs on the kick start shaft. One holds the gear in place while it gets pushed into engagement with the gears in the tranny. The other helps the gear return to the disengaged position.
If these springs get weak they will let the kick start engage the tranny a bit and lock things up.
You have the cover off so pull the kick shaft out of the engine. Now try turning the tranny shaft.
If it spins ok then your springs are weak.
It some times happens if the return spring has come unhooked or bent.
Leo
 
Checked the Shaft for turning today after replacing old bolt with new bolt in star mechanism and removing kick start shaft and it does turn but jams up but with a little bit of force (not excessive force) it continues to turn. Wondering whether to risk re-assembly and trying it or not
 
The gears don't like changing much when they not moving. Try shifting whilst turning the crank or front sprocket, it may make it easier.
 

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