2003 YZF Transmission Problem

I have a 2003 YZF450 that I bought recently with low hours on it. My second ride on it and I appear to have blown 3rd gear. I landed from a jump and it made a horrible clanking sound. I thought the motor blew up. I pulled in the clutch and killed the engine. When I started it back up it ran fine and went thru the gears but now everytime I let off the gas in 3rd it makes a grinding noise and vibrates.

Anyone else have a similar problem? How big of a hassle is it to split the cases on one of these?

Thanks in advance.

Sounds like an accurate diagnosis. Don't run it any more until it's fixed though, as the gearbox shares oil with the engine.

As far as splitting the cases, there are a lot of parts, but it's pretty straightforward. There is one case bolt up to the rear of the ignition cover that can get overlooked because it's not out on the perimeter like all the rest.

I have a 2003 YZF450 that I bought recently with low hours on it. My second ride on it and I appear to have blown 3rd gear. I landed from a jump and it made a horrible clanking sound. I thought the motor blew up. I pulled in the clutch and killed the engine. When I started it back up it ran fine and went thru the gears but now everytime I let off the gas in 3rd it makes a grinding noise and vibrates.

Anyone else have a similar problem? How big of a hassle is it to split the cases on one of these?

Thanks in advance.

This is more common than most would think - I have seen 4 cases of 3rd gear outages here in my region all on 03s...all happened exactly like you said...."I landed from a jump and CLANK"

Not too difficult to remedy....find a trusted mechanic if you don't dare do it yourself.... :applause:

After It first happened I only rode it around slow to find out what was wrong. I think I will start taking it apart and start ordering parts.

Thanks for the help.

You hit the nail on the head! I finally got around to splitting the cases and found 3rd gear had a spline missing. Luckily the broken piece fell to the bottom of the cases and did not cause any more damage. The pinnion gear is also chewed up, so I am going to replace both gears and all the tranny bearings to be safe.

Thanks for your help!

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