Sasquatch
Lifetime Member
- Joined
- Apr 17, 2004
- Messages
- 3,699
- Location
- North Western Ontario
- Website
- www.dptc.com
- Country
- Canada
- Snowmobile
- Yamaha's
I broke the driveshaft on My Warrior at about 9,000 miles. Same spot right under the collar drive side. Was only doing about 20mph and put on a little throttle to climb a small hill and nothing happened other then the motor reved up. No vibration 200 miles into the day, 900 miles into the trip and no ice chunks.
It has been said that ice is the culprit. Caused by tunnel protectors holding ice and dropping it in large chunks. Thereby jambing it into the front of the track and bending the shaft.
I have said that ice could be the straw that broke the camels back but with so many breaking on the drive side under the collar. I think that it is rotational twist over time that causes it. Other wise why not break off on the opposite side?
Add to that the collar has a set screw set into the shaft to hold the collar in place. Mine broke right under that set screw. To me that is another thing to consider. A stress riser caused by the set screw gives a place for the crack to form.
Bottom line is something starts a hairline crack. Mine had been cracked for awhile. There was some rust as in other cases as well. Now a chunk of ice could finish it off but I think like bending a wire back and forth after awhile a crack forms and it breaks.
If you think about the on off throttle, grab the brakes type riding that we do. It puts a lot of rotational force in both directions on the shaft. That force would be inbetween the drive bearing and the first driver.
RX forum was full of broken drive shafts a few years back. Found these threads.
http://www.ty4stroke.com/viewtopic.php?t=49395&highlight=
http://www.ty4stroke.com/viewtopic.php?t=57601&highlight=driveshaft
http://www.ty4stroke.com/viewtopic.php?t=53448&highlight=driveshaft
http://www.micro-belmont.com/ These guys are supposed to make a stronger replacement shaft. I replaced with a stock Yami shaft again. Guess when I get closer to 18,000 miles I will need to replace again.
It has been said that ice is the culprit. Caused by tunnel protectors holding ice and dropping it in large chunks. Thereby jambing it into the front of the track and bending the shaft.
I have said that ice could be the straw that broke the camels back but with so many breaking on the drive side under the collar. I think that it is rotational twist over time that causes it. Other wise why not break off on the opposite side?
Add to that the collar has a set screw set into the shaft to hold the collar in place. Mine broke right under that set screw. To me that is another thing to consider. A stress riser caused by the set screw gives a place for the crack to form.
Bottom line is something starts a hairline crack. Mine had been cracked for awhile. There was some rust as in other cases as well. Now a chunk of ice could finish it off but I think like bending a wire back and forth after awhile a crack forms and it breaks.
If you think about the on off throttle, grab the brakes type riding that we do. It puts a lot of rotational force in both directions on the shaft. That force would be inbetween the drive bearing and the first driver.
RX forum was full of broken drive shafts a few years back. Found these threads.
http://www.ty4stroke.com/viewtopic.php?t=49395&highlight=
http://www.ty4stroke.com/viewtopic.php?t=57601&highlight=driveshaft
http://www.ty4stroke.com/viewtopic.php?t=53448&highlight=driveshaft
http://www.micro-belmont.com/ These guys are supposed to make a stronger replacement shaft. I replaced with a stock Yami shaft again. Guess when I get closer to 18,000 miles I will need to replace again.
