sl3dneck
Newbie
- Joined
- Feb 25, 2007
- Messages
- 2
Hello,
This sub-forum doesn’t look very active, but I’m looking for some feedback. I’m kind of over the lack of engine longevity and maintenance items in the skidoo mountain sleds. I currently have a 15’ Summit Etec, I am in the middle of replacing my s-module and I suspect i will need to rebuild the engine soon based on compression and crank run out. I’m over it.
I generally only use my sled for access to go backcountry skiing. So that means a lot of doubling and travel on forest service roads. Occasionally, use to it proper mountain sled.
There are some low mileage 2015 or 2016 SR Vipers mtx in my area. So I’m considering making the switch, but I need some real feedback on these sleds. I don’t know if I should go a used Viper Mtx or a Gen 4 Summit.
Engine aside, are they more reliable then an Gen 4 doo? I’m ok with the extra 60lbs if so.
Is there anything I need to check out or watch out for?
Additionally since they have a rad, in addition to a head exchanger, how are they for overheating when there is no powder on the trail. The cats are really bad for this.
Thanks
This sub-forum doesn’t look very active, but I’m looking for some feedback. I’m kind of over the lack of engine longevity and maintenance items in the skidoo mountain sleds. I currently have a 15’ Summit Etec, I am in the middle of replacing my s-module and I suspect i will need to rebuild the engine soon based on compression and crank run out. I’m over it.
I generally only use my sled for access to go backcountry skiing. So that means a lot of doubling and travel on forest service roads. Occasionally, use to it proper mountain sled.
There are some low mileage 2015 or 2016 SR Vipers mtx in my area. So I’m considering making the switch, but I need some real feedback on these sleds. I don’t know if I should go a used Viper Mtx or a Gen 4 Summit.
Engine aside, are they more reliable then an Gen 4 doo? I’m ok with the extra 60lbs if so.
Is there anything I need to check out or watch out for?
Additionally since they have a rad, in addition to a head exchanger, how are they for overheating when there is no powder on the trail. The cats are really bad for this.
Thanks
- Joined
- Apr 13, 2003
- Messages
- 21,537
- Age
- 54
- Location
- Schofield, WI
- Website
- www.totallyamaha.com
- Country
- USA
- Snowmobile
- 2020 Sidewinder SRX
I don't follow Doo, So have no idea what a Gen 4 doo is capable of. I know a few off trial guys that love the Viper Boosted for off trail but not sure about how well the stocker performs. Maybe @yamahaguy can help and give his honest opinion.
Mtnviper
Vendor
sl3dneck,
They generally are not prone to overheating in marginal snow conditions as much as the 2 stroke sleds are. As you mentioned, the radiator helps a great deal. That being said, you still will need to use ice scratchers in low snow/hard pack conditions as is the case with most mountain sleds.
In 2016 Cat/Yamaha updated front suspension to the currently used 36" ski stance with improved geometry, this makes the sled much easier to side hill. A 2015 can be updated to the newer 2016 geometry by replacing the front A arms, tie rods and shocks (shorter travel) with the newer parts. There was a time when Cat was selling an update kit, which included the A arms, tie rods and spacers for the shocks.
Not sure if that is still the case though, but you might be able to find the parts used as well.
One advantage that the 2015 would have over the 2016 is the engine. Sometime around mid-2016, Yamaha changed the engine design, and the connecting rods are not as strong. This is usually not an issue if you plan to leave the sled stock, but if you plan to turbo it, I would definitely look at the 2015 instead of the latter years.
A couple of mods that I would do (if it already doesn't have one) is a roll over valve. Not trying to sound like a shameless plug, but seriously they really do need one if you're going to do any back country riding at all! There's nothing worse than leaking oil out when tipping the sled over, while you're trying to have fun.
The other would be a good set of skis. The mountain skis of that area were narrow and quite honestly less than ideal for the weight of the sled in the mountains. There are lots of good options on the market, but generally speaking you'll want to look for something in the 6.5" to 7" width. They will help keep the front end up in deeper snow. Keeping in mind that it is possible to go to wide and have the handling suffer for the tradeoff of more floatation.
Bill
They generally are not prone to overheating in marginal snow conditions as much as the 2 stroke sleds are. As you mentioned, the radiator helps a great deal. That being said, you still will need to use ice scratchers in low snow/hard pack conditions as is the case with most mountain sleds.
In 2016 Cat/Yamaha updated front suspension to the currently used 36" ski stance with improved geometry, this makes the sled much easier to side hill. A 2015 can be updated to the newer 2016 geometry by replacing the front A arms, tie rods and shocks (shorter travel) with the newer parts. There was a time when Cat was selling an update kit, which included the A arms, tie rods and spacers for the shocks.
Not sure if that is still the case though, but you might be able to find the parts used as well.
One advantage that the 2015 would have over the 2016 is the engine. Sometime around mid-2016, Yamaha changed the engine design, and the connecting rods are not as strong. This is usually not an issue if you plan to leave the sled stock, but if you plan to turbo it, I would definitely look at the 2015 instead of the latter years.
A couple of mods that I would do (if it already doesn't have one) is a roll over valve. Not trying to sound like a shameless plug, but seriously they really do need one if you're going to do any back country riding at all! There's nothing worse than leaking oil out when tipping the sled over, while you're trying to have fun.
The other would be a good set of skis. The mountain skis of that area were narrow and quite honestly less than ideal for the weight of the sled in the mountains. There are lots of good options on the market, but generally speaking you'll want to look for something in the 6.5" to 7" width. They will help keep the front end up in deeper snow. Keeping in mind that it is possible to go to wide and have the handling suffer for the tradeoff of more floatation.
Bill
