KDXRIDER.NET

Howdy Y'all-
I have had this '99 KDX220 basket case for a couple years and I am finally getting it put back together. Welded up the hole-y bottom end where a busted piston skirt did some damage, and replaced every single bearing. Went through the transmission and all gears, shafts, forks etc appeared to be in excellent condition and well within specs. inspected everything and replaced all snap rings, then glued my cases back together last night. Now I am messing around with shifting the transmission through the gears before I go any further to make sure everything is ok in there, and I am a bit concerned... all the gears work, but I am getting jammed up in between gears quite often. I will go to make a gear change while spinning the output shaft and the shift drum gets stuck in between gears. If I try shifting up and down it will eventually drop into the gear I was going for and then spin freely. This is my first real transmission rebuild, so I am not sure if I have a problem and need to crack this sucker back open, or if adding oil and motion (there is a little oil to lube things up in there) will have it working like normal. Thanks much for any help or advice you may be able to offer!

Yeah oil was my first guess when you said things getting jammed up. The forks have to follow the valleys on the drum, go along the fork sliders and engage the dog clutches. All things that need lubrication

So what do you think? finish assembly and see how it rides? is there any other testing I could do first? would a video help?
thanks

Doo you have the shift turret, pawl and stuff installed on the right side? Put some oil in it and run through the gears while rotating the front sprocket

turret and pawl are installed. I poured some more lube into the case an didnt have any change. Its strange, I will get several smooth shifts in a row and get excited that things are improving and then bam! jammed again.

If it were me I'd open it back up and double check everything before proceeding. If it's not shifting now, it's not going to be any better under load and assembled. Save yourself the time and headache and crack it while it's still on the bench.

can anyone who has split their cases tell me what the trans acts like when wroking properly? should it shift easily into all gears when spinning the output shaft by hand? also, if i re-split the cases and the crank bearing ends up on the crank, do i need to replace it, or can i just pull it off and re-install it in the case? thanks!

I'd have faith in your work and run it.

trying to shift a transmission on the bench is quite different from one where the motor is spinning and you load on the countershaft, full of oil and up to temperature.

KarlP wrote:trying to shift a transmission on the bench is quite different from one where the motor is spinning and you load on the countershaft, full of oil and up to temperature.

I agree. I've put several back together and none of them shifted as smooth on the bench as they did when they were in the bike. They would get hung up rather frequently on the bench.

I think a good way to feel better about it without re-splitting the cases is to bolt the bottom end back in your bike and hook the chain up. Start spinning the back tire and shift through the gears that way. The weight of the chain and tire should give a better load than what you were doing by hand.

right on thats a good idea, thank you!!