Yamaha Ovation Bog After Track Swap

[Hermit]

First time poster, long time lurker.
So my son picked up a wore out 89 Yamaha Ovation. He rode it last season pretty much stock.
This year he wanted to upgrade the track. We found a Phazer at the boneyard and were able to get the driveshaft with drivers and he picked up a 121" track from a buddies polaris.
From an old Ovation skid, he made extensions. All in all I am impressed with his work for a 15 yr old with not much help from me.
After getting the new track/skid dialed in he mentioned that he powers out trying to take off on a steeper hill.
I am stumped. Of course I expected a power loss of some sort with the larger track but did not expect this.
Do you think this could be a clutching issue or gearing issue.
I could go with a 11-tooth top gear from the ex. 12-tooth.
Any other ideas or anything I should look at?
Thanks in advance for any help!

 

[retiredpop]

Could be a bit of both clutching and gearing. The old enticer 340 trapper was geared 12/23 so I think your idea of 11 tooth top to give you 11/22 gearing may do the trick. I don't know for sure but the secondary clutch doesn't have any adjustment holes for spring twist on those sleds does it to tune backshift? You could try lighter clutch weights also or a stronger primary spring to allow the engine to engage closer to it's power band. If it is bogging right on takeoff then it could be something to do with jetting.

 

[Hermit]

Could be a bit of both clutching and gearing. The old enticer 340 trapper was geared 12/23 so I think your idea of 11 tooth top to give you 11/22 gearing may do the trick. I don't know for sure but the secondary clutch doesn't have any adjustment holes for spring twist on those sleds does it to tune backshift? You could try lighter clutch weights also or a stronger primary spring to allow the engine to engage closer to it's power band. If it is bogging right on takeoff then it could be something to do with jetting.

Thanks retiredpop! I will check to see if it has the adjustment holes and will look into the spring and weight option. Thanks again for the input!

 

[Massif master]

Bought a 440 Jag long track for my daughter and put a Bear cat 155 track and skid and sprockets on it, put better shocks allround = 1800$Ca. What a riot it was on the mountain, so light and nimble + the 2 up seat with tunnel rack. My daughter moved away so I started using it. I was a trail guy 850 xrs souped up, but after a year with the Jag on the mountain and newly found friends, I bought a new RMK 155 and sold the Jag to a young farmer mother of 5...to this day it still runs and all the kids love it!