Jump to content

2011 5th gear breaking


Recommended Posts

Frend of mine have his Yzf 450 2011 55hours on. And he just breaks 5th gear its totally destroyed. Maintance is been done nearly perfect he keeps his bikes top shape alltime. His riding speed is good and funny thing is he allmost never use 5th gear. Anyone else have this?

Link to comment
Share on other sites

Yes, 2010 with 72 hours on it.. 5th gear came apart and then pretty much ruined 2nd and 3rd gears...and floated around and ruined the primary drive gear, one of the water pump gears and scored much of the internal case. Third time I've had a transmission problem on a yamaha, 03, 06 and now the 10. I still have it but I also now own a Honda.

Link to comment
Share on other sites

Yep. Caling around i find out many have this problem beetween 50h-80h riding time i gues its depending little how hard you ride the bike. I will open my engine and replace this 5th gear. Anything else i need to know for breaking parts i can replace them too now same time. Anyway so far im happy whit my Yamahas.

Link to comment
Share on other sites

Yamaha gearboxes are crap!!!

My 5th gear came apart. The debris tracked through 3rd gear, oil pump drive, ballancer drive, and primary. The oil pump drive gear and idler had a chunk in their mesh and it jacked up the drive gear post, braking my engine case and damaging the oil pump. I just finished rebuilding it a couple hours ago. About $1300 for parts. My third and final Yamaha with transmission failures.

Link to comment
Share on other sites

Yep. Caling around i find out many have this problem beetween 50h-80h riding time i gues its depending little how hard you ride the bike. I will open my engine and replace this 5th gear. Anything else i need to know for breaking parts i can replace them too now same time. Anyway so far im happy whit my Yamahas.

If your gear broke there may be lots of other damage caused by the debris, as was the case with my bike. good luck

Link to comment
Share on other sites

never had a problem. I've had a 06, 08, 09, 09, and looking for a 2011, knock on wood

It may be a problem for heavier riders or more aggressive riders. i am a vet Expert and weigh 210. I believe my gear broke when riding hard through choppy whoops. My '04 came apart going through whoops.

Link to comment
Share on other sites

I've heard more about 2nd gear problems than 5th gear problems until now. Is there any tell tale signs if one were to inspect the tranny? I've never had any problems with my yamahas for the last eight years but I don't want to have any either. From what I hear all of the manufactures use the same grade material for their trannys, not very durable. Would the cryo or iso treatment make them stronger?

Link to comment
Share on other sites

I've heard more about 2nd gear problems than 5th gear problems until now. Is there any tell tale signs if one were to inspect the tranny? I've never had any problems with my yamahas for the last eight years but I don't want to have any either. From what I hear all of the manufactures use the same grade material for their trannys, not very durable. Would the cryo or iso treatment make them stronger?

Taking apart you engine to inspect it is time consuming. In order to see that a gear or any other part is getting ready to come apart could require very expensive testing. X-rays, Liquid Penatrant testing, magnetic particle testing or magnetic flux testing can identify defects or failures that you can't see, however any one of them will cost you more than a new engine unless you happen to be an NDT inspector with all the equipment available to you.

I don't doubt that pro level riders rebuild their tranny frequently to avoid the damage. The gears are probably strong enough for the designed durability, which isn't enough for me, but may be too much for a racer than gets a new engine for each supercross or motocross race.

Link to comment
Share on other sites

I finished rebuilding my engine yesterday. It fired up and ran fine. No oil flow in the sight glass/level window, but good oil flow to the gantry (cams). In chasing the scavenge pump circuit to see what might be wrong, I thought the left side cover gasket might be blocking the port. The oil passes through the cover to get from the scavenge pump to the tank!

I found the oil passage had a big chunk missing. Apparently debris from my gears passed between the flywheel and the case and didn't quite fit.

Untitled001.jpg

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:

×
×
  • Create New...