KX65 popping out of gear???

[OldTimer]

My son has been having fits with his '05 KX65 "missing" second gear. At first I thought that perhaps he just wasn't shifting properly and that he was shifting into neutral from 1st gear, but he's been on the bike for nearly two years and hasn't had trouble until recently. Also, he says that occasionally it will slip out of gear under power.
Is this a common problem for aging KX65 trannys, and if so, what's the cure?

 

[2 strokes for life]

I have not seen it in a KX65 but i have in a KDX one time. I cant remeber what it was called that did it but it was like a gearing shaft of some sort in the tranny.

 

[2 strokes for life]

I found out what it is called and why it dose it. It is called a Start gear and it coulbe be doing this because the teeth are worn. So, go to dealer and ask and see how much one is.

 

[SHSPVR]

2 strokes for life are you sure it not called countershaft gear usedly it six and second countershaft gear that has worn slide teeth.
Start gear as I recall is know as Kick Starter Idle Gear.

 

[SteveinSpringHill]

Yes my son's 05' did that also, but mainly the 2nd to 3rd shift. Unfortunately that bike was stolen and we never found out what it was. His 07' doesn't have that problem at all.

 

[2 strokes for life]

I am certen that it is the idle gear. This happended to mt buddies old KDX. Also, the KLX has this recurring problem.

http://www.planetklx.com/techtips/shift-fix.shtml
This is what i think the problem is. I could be wrong.

 

[SHSPVR]

That link you post that called a shift star gear and that good possable to

 

[Ol'89r]

Also, he says that occasionally it will slip out of gear under power.
Is this a common problem for aging KX65 trannys, and if so, what's the cure?

Worn shift dogs or bent shift forks or both. If the gearbox is worn, the gear dogs, or the little cogs on the sides of the gears can become worn at an angle. These dogs are how some of the gears engage. When under acceleration, the worn dogs will try to spread themselves apart. If the dogs are worn excessively and the shift fork is slightly bent, it will force the gears apart and the bike will pop out of gear. This is a common problem on a lot of bikes that are ridden hard and shifted without using the clutch. Eventually the dogs will wear off at an angle.

The cure is to split the cases and inspect all of the gears and shift forks. The gear dogs should be square, not worn at an angle. Look at the shift forks. If they are bent it will show up as an uneven wear pattern on one side of the shift fork. Usually will show wear at the top or the bottom of the fork, indicating a bent fork. The shift fork should have an even wear pattern on both sides, top and bottom. Replace the worn parts as necessary.

Probably not the answer you wanted to hear but, there ya go. :cool:

 

[OldTimer]

http://www.planetklx.com/techtips/shift-fix.shtml
This is what i think the problem is. I could be wrong.

I'll have to look at my shop manual to see if this part is in the 65 tranny, but the problem description is EXACTLY what is happening to my son. It always does it coming out of a creek bed or off a turn going into a quick uphill. :nod:

...The cure is to split the cases and inspect all of the gears and shift forks. ...Probably not the answer you wanted to hear but, there ya go. :cool:

You can say that again.
Splitting the cases is bad enough, but for exploratory surgery, well that's just a big 'ole DANG!
I guess I was hoping someone would tell me, "Oh, that's yer shift alignment adjuster, just pop the hood and torque 'er down a might". :laugh:

 

[Ol'89r]

just pop the hood and torque 'er down a might". :laugh:

OldTimer.

While ya got the hood up, ;) you can grind that star washer or detent washer yourself. Using the photo link that 2 strokes for life provided as a guide, remove the washer and grind the tips to match. If the bike still pops out of gear after grinding the star washer, then you will have to split the cases.

 

[2 strokes for life]

Good show everone. OldTimer you have some good knowledge.

 

[OldTimer]

Well I had to split the cases to replace the crank shaft this week and had a free look at the transmission. I was amazed at the total lack of wear marks of any kind! The inside of gearbox look showroom new. I guess I'll have to blame it my kids ankle strength until I can find a better clue of some mechanical problem.

 

[whenfoxforks-ruled]

No you need to look better! Measure the thickness of the forks,are the dogs rounded,negative rake-good,positive-bad. Shiny can be a bad thing!

 

[OldTimer]

Okay, measured the shift forks, dogs, drum grooves and gear grooves. All were within standard range and nowhere near wear limits. All were square and true. I had just about given up hope of finding any clues when I noticed that the little roller that follows the shift mechanism on the right side in the clutch compartment, called "positioning lever", was scarred and worn. This led me to check the little cam that it rides along, called the "holder". It has a little half-moon cutout that acts as a detent which is worn badly. A check of OEM parts fiche on Bike Bandit shows the parts costing about 42 dollars together and do not require splitting the cases to access.
I assume this is another version of the "Star Gear" thingy mentioned in earlier posts in this thread.
If anyone else is experiencing this problem, I may be able to get some photos or use this link to the parts fiche:

Part #13236: http://houseofmotorcycles.bikebandi...id~1127166~model_dept_name~KX65+(KX65-A5).asp

and Part#13280
http://houseofmotorcycles.bikebandi...id~1127166~model_dept_name~KX65+(KX65-A5).asp

 

[whenfoxforks-ruled]

How the heck did that happen is the question,not a high wear item? Need pictures,was the detent in alignment,what hit it,how do you wear out a holder?

 

[OldTimer]

Oh, they were definitely misaligned. Only about half of the 1/8" overall width appears to have been making contact.
Unfortunately, there doesn't appear to be any adjustment, I guess you'd have to bend the bracket if you happened to notice it before it were too late.
At any rate, I'll have to get the rest of the motor put back together before I can tinker with that portion of it because the parts are all plied up in a box.
Besides, I'm not even sure that it comes into play as far as 1st to 2nd gear are concerned. Again, I'll have to tinker with it.

 

[whenfoxforks-ruled]

There should be a spot on the clutch cover responsible for holding your shaft in place,check this also. This did not start as a tip over or accident to the shifter did it?

 

[OldTimer]

...Besides, I'm not even sure that it comes into play as far as 1st to 2nd gear are concerned. Again, I'll have to tinker with it.

Okay, put the cases together today and discovered that the little detent in the "holder" is to lightly hold the shift drum in neutral and doesn't come into play as far as causing the transmission to pop out of gear. In fact, if it were worn out, you couldn't get the bike into neutral.
I've been studying the bottom end of this engine for a couple of weeks now, and I'm satisfied that there is nothing mechanically wrong with this bike's tranny. If there is any problem, it would be a design flaw and is nothing that hasn't been there since day one. Unless perhaps, the spring that holds the little rollers against the "holder" has lost some of its tension, and that doesn't appear to be the case.

 

[whenfoxforks-ruled]

On them dogs there were no shiny radii on the corners,the male to male gears,or male to especially female! Most all the detent springs on the drum are under a lot of tension,I can not say I have heard of the springs going bad,misaligned,yes. Under cutting the dogs is a good set up for a smooth,carefree operation.81 cr 250 out of the crate were positive raked and scattered transmissions like a box of crackers,honda fixed it and put out a bulletin to undercut! They were jumping out of gear also! I do not know how long a trans would last if the dogs were at a right angle,undercutting any to about 2 degrees will eliminate this problem. It is a nice to have machinist friends! Bet you Eric at forwardmotion.com could fix it! Them dogs under load are forcing it out of gear,welding the drum in place will not hold it in gear! If the trans is missing shifts I would suspect the detentes or forks,if it is jumping out of gear its the dogs. The detentes biggest job,with proper alignment and sequencing is to hold neutral.

 

[ssomerville]

We had a brand new 2005 KX65.

It would sometimes miss the 2-3 shift.
It was very difficult to find neutral.
The most fun was when my son thought he had it in neutral and it would magically jump into gear at idle with his left foot nowhere near the shift lever!

He is on a CR85 now and is much more happy regarding shifting. Maybe I'm biased having had mostly Hondas, but I thought the little KX transmission was problematic, especially for a beginning rider.