2016 Yamaha RS Venture TF BAT - Clean Snow Challenge MTU

[mtuyamaha]

Hi all, I am the chassis team lead for the Michigan Technological University SAE Clean Snowmobile Challenge. Our platform is the 2016 Yamaha RS Venture TF BAT.
This is the link to our design documents as well as test results from the competition.

http://www.mtukrc.org/mtu2019.htm
​

The goal is to improve fuel economy while reducing noise, vibration, and vehicle harshness. We do this while maintaining performance and practicality.

This will be our third and final year on the Venture TF Platform due to competition guidelines. We came very close to taking home first place, however, we missed the sound limit by a less than a decibel. I'm reaching out to hear what your concerns/ what you would like to see improved on the sled.

Also, if anyone has any questions about what the team has done/ learned about the sled from testing and developement I would be happy to answer!

 

[yamadoo]

Sounds interesting thanks for posting.

In regards to the Noise Vibration Issues a major recurring theme on these 4 stroke rear exhaust sleds has been the ‘track howl’ . If your team could reduce/eliminate this all of us Venture, Vector, Apex guys would be very interested !

Thanks for thinking of how to improve our sport and sleds

 

[mtuyamaha]

Yamadoo,

One of the best ways to help eliminate the track howl is to run a track that is ported. The main advantage of the porting is the reduction in the pressure difference between the track and the tunnel.

In addition to the track porting, we have removed all skid wheels that are non-essential. We run the DuPont slides, of course, to help reduce the build-up of heat on the hyfax. We found that the factory wheels aren't always symmetric and cause unwanted frequencies. I know that removing the hyfax saver wheels is a little impractical and can be costly to change DuPont slides every year.

 

[THKSNOW]

Yamadoo,

One of the best ways to help eliminate the track howl is to run a track that is ported. The main advantage of the porting is the reduction in the pressure difference between the track and the tunnel.

In addition to the track porting, we have removed all skid wheels that are non-essential. We run the DuPont slides, of course, to help reduce the build-up of heat on the hyfax. We found that the factory wheels aren't always symmetric and cause unwanted frequencies. I know that removing the hyfax saver wheels is a little impractical and can be costly to change DuPont slides every year.

Ok, I'll bite. How do you make a track "PORTED?"

 

[THKSNOW]

And, what wheels were found to be "non-essential?"

 

[mtuyamaha]

Track porting shown below. Basically it reduces the "pillow" that develops at the front of the tunnel. As the track spins it is trying to compress the air at the front of the tunnel. Creating unwanted resistance as well as drone.

Non-essential meaning removing all of them besides the front shock wheels, rear idler wheels and the wheels the upper idler wheels. Keeping the ones I circled in red.

 

[mtuyamaha]

We also run a catalytic converter as well as custom resonators. The stock muffler is utilized with an additional box that fits nicely on the rear bumper to direct the exhaust downwards. We have validated that routing the exhaust downward reduces the exhaust noise a little bit.

 

[THKSNOW]

Thanks for the information. Did you notice any negative results by removing those wheels... like increased hyfax wear or handling issues?

 

[mtuyamaha]

Thanks for the information. Did you notice any negative results by removing those wheels... like increased hyfax wear or handling issues?

We run the Dupont slides which I recomend regardless. However, in low snow conditions, there will be excessive wear on the slides. I currently have about a thousand miles on one set of hyfax that are still adequate for probably another thousand. Which is really good seeing how I can barely get 500 miles out of my Arctic Cat mtn cat 153 that also has basically no boogey wheels. Disclaimer, we test in increments of less than 50 miles in the best snow conditions you could imagine. However, this past summer one of the senior design teams did extensive testing in a grass field with soapy water and the hyfax/track clips don't have signs of excessive heat coloring.

 

[Mooseman]

That is a cool project and goal! Love the idea of improving our sport for the future as that's the direction of things to come.

Not sure if it's one of the design parameters or if you are constrained to a particular type or model of sled but, other than a mountain sled, the TF has one of the longest stock tracks at 153" . That's a lot of track to spin and to make noise. If you could switch to a 144" suspension and track from an RS Venture GT, it would probably help with fuel consumption further as well as track noise. You would lose some flotation though if that's one of the parameters.

 

[mtuyamaha]

Mooseman,

That's a great thought. As of right now, we are going to test a phazer skid (144) along with a 10" aluminum idler wheels to take up the track slack. This will hopefully eliminate some skid noise as well as improve mpg. I will post pictures once we have the offset axle machined and installed. We have found that the most efficient track is between 136" and 146". The medium track length also provides better trail manners.

 

[Metallicat]

Hi! I am an MTU grad, class of 1994. The snowmobile challenge has certainly become more difficult with di 2 stroke and 4 stroke technology in play. Enjoy Winter Carnival and the most wonderful place on Earth, Houghton. I still miss my old stomping grounds! And Triangle.

 

[Snorunner]

I have seen track porting advertised before. For mountain riders it reduces weight in deep snow. As far as reducing friction to gain mileage I would put the wheels back on and find a way to reduce the friction in the bearings if that's allowed. I use to sponsor oval ice racers with a synthetic metal conditioner. They actually complained once that if they fell off the sled it would go to the other end of the track before stopping. They used it in their bogey wheel bearings. One of them even told me they pushed the sled up to the starting line. Without the belt on of course. The other racers were dumfounded by this. Not sure why but they felt it gave them some advantage. At the start. Mixed into their fuel or 2 Stroke oil it would increase top rpms by about 200 rpms. Now I am going to have to redo my clutching was another feedback I received. Drag racers that we're using it would add it to their chaincase and then just run ATF. Hope this helps. I once gave Mankato State some for use in their Clean Challenge Sled many years ago. Never got any feedback from them though. I also gave some to Tucker Hibbert in his race trailer at Hay days many years ago because I was Cat Fanatic then. Never heard from him either but that's ok!

 

[Metallicat]

The clutch rattle is pretty pronounced on these sleds. The splined crankshaft is the cause of the rattle. This could be one area to look at, and if you find a solution patent and sell it. You'll be a hero on this site! Intake noise can be noticeable as well. Perhaps the airbox can be better insulated to absorb some noise.

 

[sailor joe]

Thanks so much for the research and trying to keep the noise down...I never thought engineers from a college would tackle such a project...certainly the engineers at Yami could care less about track howl/drone. I have a 2016 RS Venture TF and the track drone drives me nuts...my last ray of hope to get the noise to go away was to purchase Bose noise cancelling earbuds like so many have recommended...just got them and then I came across this article here in Totally Yamaha.
Porting the track as you put it makes sense, but who would ever think of it?!! It seemed the drone was coming from the tunnel but why? Your explanation seems logical. Porting the track would reduce the pressure for sure...my question would be this: does porting the track lead to a severely weakened track? The Camoplast track on the Venture TF is 151" and only 1 ply...being 1 ply have you had any problems with tracks ripping/ being damaged and does porting create another problem by picking up debris and sending it into cooling system in the tunnel?
When your modifications are done with the 10" wheel and shorter skid please please let us know!! Again thanks for all the hard work...there are allot of TF riders out there who'd like to be rid of the drone and allot of dealers/mechanics who'd like to know how to fix the problem...I've asked many and so far the fix has been 1) get earplugs 2) go faster 3) sell the sled. Great work and good luck on future projects. Joe