Odd (Maybe) Part Failure

B

bilbo

Member
#1
#1
I had an unexpected failure this weekend. I was riding my Tri-Sport (TS with 8HP engine) and hit a couple of gopher mounds hidden under the light snow and then snap! I thought the chain had broken, but when I looked, the jackshaft sprocket was gone! I picked around in the snow where the snap occurred and found one half of it. It broke at the keyway. Makes sense as it would have the smallest cross section of metal. It was a hardened sprocket that came from McMaster a while back or a different project.

I'm thinking the bouncing on the gopher mounds made the wheels leave the ground and spin, and when they connected back up the shock load snapped the sprocket. I'm wondering if the hardened sprocket has anything to do with it too? It definitely was a brittle fracture. Maybe a non-hardened sprocket would be able to take shock better?

One more comment, this machine is every bit as fun as I thought it would be in the snow! I need to figure out a way to keep snow and water kicked up by the front tire from collecting in my crotch though. Makes things a bit numb after a while.
 
W

wjustice

Well-Known Member
#2
#2
How many teeth was that sprocket? Smallest you can usually get is 10. I have some 9t but I've never broken one. The 9t are special as the keyway cuts into the undercut for the chain and that weakens them.
Make some rubber mud flaps for the top and bottom. They help a lot.

Sent from my XT1585 using Tapatalk
 
B

bilbo

Member
#3
#3
It was a 10 tooth. I did make a mud flap for the bottom, but didn't get to ride it much before the sprocket failure. Seemed to help though. I'll make one for the top, too.
 
Sixpac440

Sixpac440

#4
#4
I was recently going back and forth with a guy who owns the same Wards 30" cut rider mower from the 80's that I have.
He had the same thing happen ... his was an original 8T #41 sprocket.
So yep, it happens!
 
jeep2003

jeep2003

#5
#5
iv broken a couple like that. I figure it was from a bent/warn chain that maybe got jammed up or maybe a stone got in it. one was on a tav the other on a jackshaft
 
we4amigos

we4amigos

Member
#8
#8
These things fling snow everywhere lol The back tires,front everywhere and if its a slushy snow you get pretty soaked. I'm thinking of making a ski for the front of mine like they sold as a accessory item. Just not sure how well these trikes will turn with one.
Anyone on here have one they've tried ???
 
B

bilbo

Member
#9
#9
steven Durham said:
I often would put on an extra sprocket on the jack shaft so that if I wanted to change the ratio it was easy to do.
Steve
Click to expand...
That is a great idea. My jackshaft is a bit long, so I should be able to fit a couple extra sprockets on there.

I was thinking the same thing on the ski. I've been on the hunt for an old/cheap ski from a snowmobile that I could repurpose. I can't imagine it would turn any worse than the tire in the snow. Unless I'm slowing down, it's hopeless. The directional brakes are pretty much the only way I can turn.
 
W

wjustice

Well-Known Member
#10
#10
I did that with my big TS. When I switched to a 9t since they are weaker, I put 2 on the shaft and left the 10t. Just in case.

Sent from my XT1585 using Tapatalk
 
You must log in or register to reply here.
Top