2009 Yamaha Vector GT

[CJS]

Good Morning,
Looking for some help, I am new to the Yamaha four-stroke world and am having a problem with this sled. Today will be the 3rd time back to the dealer for the same thing. Out riding sled codes 42 & 84 bring to the dealer they clean speed sensor , test for 1/2 hour good to go, Head out riding hour into the ride happens again lucky to get back call the dealer sled coding 42 & 84 again, drop sled off speed sensor replaced - Head out yesterday beautiful day trails are awesome , hour into the ride and here we go again , limp back to the truck coding 42 again..
Has this happened to anyone? Any ideas what may cause this?
thank you in advance for any help you can offer

 

[steiner]

Bad driveshaft bearing can cause the speed sensor not to function correctly but the dealer should have caught this.
My guess is that there is a bad connection in one of the ground blocks. These ground blocks are known to cause electrical issues.
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[CJS]

Thanks for the reply , dealer advised it could be the bearing the first time but said it was nice and tight. I am bringing it back there today, just need to be careful as not to overstep when i suggest this however enough is enough.. I need it fixxed..

 

[Yogi_12]

I change that bearing on my venture every two years. It’s actually a pretty easy job and my experience is that whenever that bearing goes... driveshaft moves and destroys speed sensor and chain case and other parts ... which are crazy expensive for all brands.
These bearings spin at a screaming pace....in harsh conditions .. I’d change it anyway for peace of mind.... as its not expensive. I suspect your problem is actually the sensor ... but I’d change bearing anyway.