Topic: tell me what cause this?

[kranta]

so i have asked this several time earlier but i havent get straight answer. so please tell me what cause these marks on my gearshift forks? i wana know why those marks are there? my center fork is above 6mm and left and right forks are above 5mm and servicable limits are for center 5.6mm and left and right forks 4.6. so what cause this and what happens if i use these forks?

i appreciate if someone can answer on here.
sorry about bad english

[MCRider]

the arced marks halfway around the semicircle are caused by the fork rubbing on the groove in the gear. This happens because the fork is bent. Forks get bent because the operator was shifting too aggressively.

For that matter, any mark on the fork not at the ends of the fork, where the tips bulge a little bit and are machined flat, are because the fork is rubbing the gear when it shouldn't be.

The forks need replacing and maybe the gear they engage as well.

If you go ahead and use them, they may not engage the shift all the way and it will jump out of gear. If they haven't already, they will hog out the groove in the gear over time.

[flybox1]

+1 to this ^^^

If the PO was hard on the gears while shifting, you also should inspect the dogs on all gears for excessive wear/rounding on the main and counter shaft, as well as check for excessive wear in the channels of the fork drum itself.
The combination of bent forks and rounded dogs will increase the likelihood of the bike slipping out of gear.
I would NOT reuse those forks.

[kranta]

thanks!