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Unknown Transmission Issue

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I recently got a 2005 Crf250r and it ran fine when I got it, but after riding it a little bit the third gear seemed to be acting strange. I would be riding in third and the bike would just act like it was hitting neutral while I was just riding. No matter how I rode it, 3rd gear always kind of skipped. When I would give it some gas, it would take of but then It was like I pulled in the clutch really fast and let it out. It only does this in third gear and everybody that I've talked to says that it was either a shifting fork was broken or a chipped tooth on one of the gears associated with third in the transmission. So I took the bike to a local mechanic to have the case split and when he had it split and started looking at it, there was nothing visibly wrong with the transmission. I even looked at it and couldn't find anything wrong with it. He said there was no visible evidence of any failure with the gears or shifting forks and everything looked correct. The only thing was a very slight sign of wearage on the shifting fork by 3rd gear but he had to measure it to even notice. The transmission smelled as if it was "burnt" in his description and the transmission oil was very silver and there were small pieces of metal in the case but he can't figure out where they are coming from. Does anybody have any idea of what could be making it mess up in third or what could cause the shavings? I expected something with the clutch that caused the silver oil but I have no idea about any of the rest. 

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I recently got a 2005 Crf250r and it ran fine when I got it, but after riding it a little bit the third gear seemed to be acting strange. I would be riding in third and the bike would just act like it was hitting neutral while I was just riding. No matter how I rode it, 3rd gear always kind of skipped. When I would give it some gas, it would take of but then It was like I pulled in the clutch really fast and let it out. It only does this in third gear and everybody that I've talked to says that it was either a shifting fork was broken or a chipped tooth on one of the gears associated with third in the transmission. So I took the bike to a local mechanic to have the case split and when he had it split and started looking at it, there was nothing visibly wrong with the transmission. I even looked at it and couldn't find anything wrong with it. He said there was no visible evidence of any failure with the gears or shifting forks and everything looked correct. The only thing was a very slight sign of wearage on the shifting fork by 3rd gear but he had to measure it to even notice. The transmission smelled as if it was "burnt" in his description and the transmission oil was very silver and there were small pieces of metal in the case but he can't figure out where they are coming from. Does anybody have any idea of what could be making it mess up in third or what could cause the shavings? I expected something with the clutch that caused the silver oil but I have no idea about any of the rest. 

 

The dog splines are rounded on the transmission gears or the bushings the gears ride on are loose from wear.

This becomes a snowball effect as one will ruin the other, as well as the shift forks.

Hopefully you still have the motor out of the bike. It needs to come apart again.

You need someone that has better knowledge of motorcycle transmissions to take a look. Its not rocket science. 

You need the gears of off the shafts to  inspect them. Well not really, but it'll be easier to see.

You'll need to closely inspect the gears and watch them go through their motion with the cases apart.

Look at the drum as it rotates, and watch the forks slide the gears on the shaft. 

Once the gears are in place there should be no side to side movement.

Check the gears for wobble on their shafts. Check the spline dogs.

The edges should be sharp and not rounded, on both the male and female side of the engagement dogs.

Get a new mechanic...

 

It could also be a loose bolt at the ratcheting lock on the shift drum. Or a foreign object stuck in the ratchet pawl. But this is less likely. 

Edited by nesc103y

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