2008 Suzuki LTZ 400 shifting issues

[Chris41586]

I bought a 2008 Suzuki LTZ 400, and right away noticed it wasn't wanting to shift into 3rd well, if at all. I opened my clutch basket, and a little piece of a gear fell out. A friend helped me strip the motor down, and ended up changing 4th gear (that's where the piece was from) and I believe third gear drive. He said everything else looked good, so I put the bike back together and started it up for a test ride. Right away, I noticed the same shifting issue, first and second go right in, but doesn't want to go into third. The other issue that may be related, is I have a hard time finding neutral. Most of the time it goes right from first to second, and I have to lightly click down for neutral, and it takes a few tries. Please give me any advice for things to look at, or reasons I would still be having this issue after changing gears. Maybe the original problem is what caused third gear to break in the first place?

[Mech]

Morning Chris. Saw this yesterday but got side tracked.

I'm glad to hear you got it apart and back together successfully.. No oil leaks ? Bad noises ? Runs ok ? Well done.. You can do it !

Now, I bet you didn't check the gear shift before putting all the side cases and everything on as you were assembling it. That's important because gearboxes are a common difficulty. It always pays to check the shifting as soon as possible during the assembly. The manuals even say that ! Before you even have the shift shaft in you need to check the operation by rotating the shift drum by hand while turning the gear shafts. This is as soon as you have the cases together with just the crank and gears, shift barrel and forks in there. If there is any problems that's the time to back track and correct it. Make sure you turn the shafts heaps, and both of them, and backwards and forwards when checking. Do it during assembly before you fit the detent.. Explained down a bit further..(I'm editing)..

So...I suppose you checked the shift forks for obvious bends, and that you could get a neutral when it was assembled. I can't think of anything obvious or that I've ever found that would cause one gear to not engage, other than a fork in the wrong place. Trouble there is that for years now shift forks have been carefully designed so they are hard to confuse.. Not impossible but difficult. It's probably possible to fit a gear backwards on the shaft too, but that should be obvious because, once again, they are designed to be self explanatory... One side has three engagement dogs, the other side has four.. something like that.

I think you need  to disassemble it again probably, but if it was me, and it was possible to take the clutch side cover off in place, I'd do that before I pulled it all out, and I'd check the shift operation without the shift lever or ratchet. I'd do that even after I'd pulled the engine out. I had a quick look, and will have a complete read later, but for now I'm thinking that the shift barrel has a series of pins poking out it's end that the ratchet engage with. Some bikes those pins come out, and there is a spare hole.. If you use the wrong holes you will have problems there. Also, the neutral switch, that could possibly stop the barrel rotating if it was fitted backwards(the switch, not the barrel). That can be removed easiest so check that first, then take the side cover off and check the barrels rotation and operation. Be aware though that sometimes to get gears to shift during assembly, you need to turn one or both shafts several turns before the drive dogs line up and allow engagement.

It would probably be a good idea to jack the bike up and try shifting gears with the lever while turning the wheels back and forwards, possibly several rotations in both or either directions will be needed. Then if the lever comes up solid when engaging third, after you are quite sure you've turned it heaps, there will be some things for us to check, or, if the lever moves enough but does nothing there will be other things to check. Either way it needs then to have the side case removed and the same check done while rotating the shift barrel by hand. If you have the side case off, it would be a good idea to remove the shift detent, the thing that's spring loaded and holds the shift  barrel in one gear or the next,, a sort of start shaped arrangement. Leave the star on the barrel but remove the spring loaded bit. They can cause problems shifting manually on the barrel. Then try shifting  the rotating shift barrel by hand while rotating the drive or clutch, or both.

If it still won't shift then, and you've noted whether it's not moving, or moving but not engaging, it's time to strip it down again I'm afraid buddy.

It will probably be, sorry to say, and no offense intended, human error. I did warn you about checking the shift operation when we had been talking earlier..  We will get it though, and it will be a good learning experience..  haha..

 

[Chris41586]

Hey Mech, I do remember my friend specifically going through the gears before assembling the motor back together. Today I took my bike back over to test ride, and when he hopped on, it was shifting just fine all of a sudden. It did stick just a little at times, but he pointed out that with having the new gear, it may need to be ridden a bit to smoothen out. One thing I had been doing before, was trying to "baby" the gear when shifting, and I had tennis shoes on, so it felt like I was shifting harder than I really was. It actually seems to be working fine now, so I was probably being paranoid haha. I do appreciate your input as always, and now I'm ready to get out and ride!

[Mech]

Yup well quads are a bit more fussy about their gear changes than two wheelers even.

If you want nice gear changes, it always pays to wind them up/out to a few revs(more the better I think), and then close the throttle off sharply and then back on again as you change up. Same as on a two wheeler. And changing down it always works much nicer, both the change and the bike behavior, if you give the throttle a quick blip as you press the gear-change down a gear. A blip, then a bit off, and then back on enough to match the needed revs. The very momentary bit off takes the load off the gears so they can slide, and the blips gets the two shafts spinning at near the right speed to synchronize the gears.

Bikes and quads need a lot more active participation in the driving techniques than a car. And quads the most of all in my opinion..