1999 Honda TRX300ex Sportrax Gears stuck

[Newber]

Good evening. So I'm in some serious need of help. I have a 99 honda trx300ex sportrax. It was just completely rebuilt top and bottom end. Here's my problem though I can't start my quad without jumping solenoid. As it's trying to start its already moving. I thought ok clutch is out of adjustment since it's brand new. Adjust clutch and same thing happens. Also notice I can't find neutral no matter what I do. Went ahead and jumped solenoid got quad running and take off. Shift to 2nd gear and it comes to a dead stop stalls the engine out and dragging the rear tires. Go to start it back up and notice this time it's trying to roll backwards. Get it cranked and sure enough now im in reverse. Has anyone got any ideas on this

[Mech]

Sounds like the gearbox has been put together wrong..

I'd jack the wheels up and turn the wheels while I changed gears with my hand, without the engine running.. Checking it did get all the gears, and in the right order. If you take the spark plug out, and turn the wheels forwards, they should turn the motor over if everything else is right.. You may need to turn the wheels back and forwards to get the gears to change, and it may take several rotations while you are holding the gear lever up or down, but you should get every gear, and if you turn it forwards you will hear the engine turn faster in low gears, and slower in higher gears..  Check it by hand..

If there's a problem, I'd pull the side case and check the gear change mechanism there/then,  before I pulled the whole thing apart again.. it might be just in the outer case.

[Newber]

With wheels off the ground it won't roll easy at all. If the clutch and basket are in the engine it will only shift to first and when you shift to 2nd it makes the click and you can see the shifter lever try and move but it goes nowhere. We tried this and maybe someone can explain it. So we rechecked the clutch and for the heck of it tried shifting with it out. Clutch and basket in hand it shifted through all 5 gears. So we took the clutch and basket feom.our other 300ex that runs perfectly fine as soon as we tightened it up the motor gets super tight again and you can't shift it. If you just loosen the clutch pressure plate it's easier to rotate wheels but still not easy to shift and find gear past 2nd

[davefrombc]

Is it possible you have the wrong length bolts  in the clutch assembly? I've seen car motors locked up because  in replacing a motor they used bolts for a manual shift flywheel to install a flex plate for an automatic.  The longer bolts contacted the motor block when tightened  and effectively seized the motor. Something similar could be happening in the Honda if one or more long bolts got swapped in where shorter ones were called for.

[Newber]

We tried a complete clutch, tge basket, bolts, nuts and washer from our other 300ex thinking maybe something was out of whack and it still does the same exact thing. What's really puzzling us now is that neutral is reverse and reverse is reverse 

[davefrombc]

There's something not indexed right in tranny assembly then That is most likely the reason for the lock up.  There should be a  manual in the downloads section  that can help. 

[Newber]

There's a download section on the site? Does the case have to be split to check that or can it be done with just removing the side covers?

[Mech]

Downloads are up top in "More", then service manuals or something which open a new page, then on the right choose the make.

"as soon as we tightened it up".. Was it the nut on the gearbox shaft that you were tightening up, or the four pressure plate bolts ?

I think you need the manual, then check the change mechanism in the side case, and if it's not that, then it will be the gear shafts not put together right.  Did you have the gears off the shafts ?

Edited August 16, 2022 by Mech

[Newber]

So if we loosen the pressure plate the drum will actually turn but as soon as you tighten the pressure plate the drum is rock solid. Can't push the quad unless you put the side cover on and squeeze the clutch. And it's still not easy then. And im not sure if the gears were off shaft or not. It was at a reputable repair place when the rebuild was done. I know we're all human and make oops im just hoping that it's a small one

[Mech]

But the motor does turn ?

The clutch hub and basket have spacers/sleeves and washers in the setup..  Perhaps check all that against the manual. The reverse though... that's another matter..  I'd find what's wrong with the clutch, so you can perhaps report it to the shop, then I'd try and diagnose the gear pattern without taking too much apart till I'd talked to the shop about warranty.

[Newber]

Yes the motor does turn. I can start it by jumping the solenoid and drive it in 1st gear. Shift into 2nd and it's like hitting a brick wall with the anchor at max chain length and motor just dies

[Mech]

Yeah and second is really reverse you said.. I think ?

That's not right..  My guess would be(because it's probably the easiest if you aren't reading the book or being careful), that they have muddled two shift forks up..

I don't think the gear change mechanism in the outer case could cause the reverse problem..  That mechanism is really just a ratchet so the lever goes to center..  The gear shifting/selection is all about how the gears are on the shaft, and how the shift forks engage in the shift barrel. If you have the side case off you can remove the ratchet mechanism and rotate the shift barrel, and the gears should all engage in order R-N-1-2-3-4-5- and without two gears being engaged at a time.

The clutch dragging/locking is a different matter and should be relatively easy to suss.

 

Check the clutch doesn't have an extra steel or friction in it.

 

[Newber]

We did take the clutch and basket bolts everything out of our other 300 and put them in but still the same problem. As soon as you tighten the pressure plate completely it's like the engine just locks together. I didn't get to work with it last night but I will today. Maybe I can see something with what I've been told to look at

[Newber]

And yes. So I can go in first and drive it. I have to jump the solenoid to crank it though while holding the clutch in. So im.driving in 1st gear. Shift to 2nd and the quad just stops completely engine dies. So without moving anything and restart the quad let go of the clutch and now your in reverse. Twice I've tried it and it wouldn't move period just stall the engine

[Mech]

It's not a model we get here so I haven't had one exactly like it apart, but I had a look in the manual last night and it certainly seem to be that it must be inside the center cases, a gear on a shaft wrong, or a selector fork in the wrong place.

You should probably take it back to who did the work. They should fix it for free if they are reasonable. They won't want to take responsibility though if you have pulled it right apart so they can't be sure it is their work that caused it. So far, with only the clutch side off they shouldn't be able to quibble.

As for the clutch, I don't understand what the problem is there. Once the springs are done up on the clutch the clutch is meant to be locked up, it should only slip if the cover's on and the clutch lever pulled in. It doesn't really sound to me like there is any problem there. I suspect you are mistaking the gearbox getting two gears at once(which will lock the gearbox solid), for a locked up motor.

If I was you, I'd take the clutch off, take the drive chain off, and disconnect most of the gear change mechanism. I'd leave the detent that holds it in gears, that's a lever with a roller on it that presses against the selector barrel. Then while spinning the gear shaft the clutch goes onto I'd try getting all the gears by rotating that selector barrel. If you have the problem then, I'd leave it like that and take the  bike back to the shop and show them what's happening. They shouldn't object too much to your having confirmed there is a problem before bringing it back to them.

Other than that I'm pretty damn sure you are going to have to strip the motor and center cases to cure that. It's a worry though that they aren't competent. Perhaps they would agree to you taking it to a local honda dealer and them paying for the repair..  You would need to be confident and diplomatic to wrangle that though.. An independent mechanic to argue your case might help.

 

[Mech]

Did the guys that did the work have the whole bike when they did it ? They should/would have test run it surely, and tried the gears ?

[Newber]

Man that sound like it's gonna be a headache and a half. And unfortunately no while they were rebuilding the engine I had the frame over being powdercoated and all the plastics painted. And between all that my job offered me a position I couldn't turn down. So honestly I got the bike and engine separately and put the engine on once we got moved. They said they bench tested it ran it through the gears. Only problem is there back in Texas and we're in south carolina now. I'll try some of the disassemble and see if it changes anything 

[Mech]

Apart from cam timing, gearboxes seem to be the second most common problem people have putting bikes together.. They shouldn't, it's so easy to test they are shifting right before you even put the second case on, but... People just seem to prefer to hope it will come right even thought they know somethings not right..haha

If you are having to do the work yourself, remember, it's better to backtrack and get it right before you go any further. The further along you are, the least inclined you are going to be to backtrack when you have finally accepted there's a problem.

As mechanic I know, we can write off some hours, it's only an hourly wage and I can make that back up, but my reputation, and the customer confidence and trust, that can't be easily won back..

[DAFinner]

Hey Newber, I'm curious on what you found out on your gearbox issue. I just picked up a 96 trx300ex that's been outside with no plastics for the past decade or so and would like to learn about any problems to avoid while working on this restoration project. Thanks in advance.

[Newber]

Well I done everything at home I could shy of splitting the cases. Didn't have the resources to do the case split. Found a guy here that would open them up for me and recheck things. Just dropped it off this week and haven't heard the outcome yet. He's thinking it's a fork that was put in wrong. I will let you know soon

[DAFinner]

Okay. Best of luck to you. Appreciate ya letting me know when you do find out. Thanks

[Newber]

Well group it's been a few weeks. Took the quad to this supposed awesome repair shop been there for weeks now. All for him.to tell me he wasn't able to locate the issue and wasn't sure what to do with it. Remind me not to go back there. But I've decided to tear this thing apart myseland check it out.