Frostbite
TY 4 Stroke God
No, sorry it's not about Yamaha fitting all of our mountain sleds with a rear heat exchanger but this is a very significant issue.
Anyone who rode their RX-1 in areas with changes in elevation probably noticed something. As your sled gained altitiude it lost RPM on top. Right? If it turned 10,200 at a lower elevation you were lucky in some cases to get 9,500 RPM. We had all led to believe the four strokes were supposed to be LESS suseptable to elevation changes than our two stroke brothers.
Guess what? They are less suseptable! I called Barry Holtzman today to inquire about an ATACC system for my RX-1 Mountain. We had a nice conversation and he said it is ALMOST dialed in for the RX-1. There is an issue with the stock pilot jet size being too lean currently. A fix is on the way in either a shielded needle jet or fatter pilots.
Here's the reason for the making the post. This completley blew me away. It seems Yamaha completely overlooked something! The carbs on our sleds a vacuum activated. Right? Stick with me now. As you gain elevation there is less pressure and consequentially less vacuum available. It seems Yamaha never took this into consideration. What we currently have are carbs with slide springs that are too heavy for the lower level of vacuum to overcome at altitude.
Holtzman engineering has designed and is marketing (I just ordered mine) redesigned carb slide springs based on the altitude your typically ride. I think Yamaha should fix this under warranty but that may never happen.
Here's the deal. They have springs for 0-4,000 feet, 4-8,000 feet and 8-12,000 feet. The springs retail for $39 a set ($44 with shipping). He guaranteed I'd gain a 1,000 RPM by this very simple spring change. All I can say is WOW! Now I can throw more weight at my primary clutch and not have to clutch for the lowest common denominator. Hey, for 39 bones and 30 minutes it sounds like a hell of a deal. Powder Blue
Anyone who rode their RX-1 in areas with changes in elevation probably noticed something. As your sled gained altitiude it lost RPM on top. Right? If it turned 10,200 at a lower elevation you were lucky in some cases to get 9,500 RPM. We had all led to believe the four strokes were supposed to be LESS suseptable to elevation changes than our two stroke brothers.
Guess what? They are less suseptable! I called Barry Holtzman today to inquire about an ATACC system for my RX-1 Mountain. We had a nice conversation and he said it is ALMOST dialed in for the RX-1. There is an issue with the stock pilot jet size being too lean currently. A fix is on the way in either a shielded needle jet or fatter pilots.
Here's the reason for the making the post. This completley blew me away. It seems Yamaha completely overlooked something! The carbs on our sleds a vacuum activated. Right? Stick with me now. As you gain elevation there is less pressure and consequentially less vacuum available. It seems Yamaha never took this into consideration. What we currently have are carbs with slide springs that are too heavy for the lower level of vacuum to overcome at altitude.
Holtzman engineering has designed and is marketing (I just ordered mine) redesigned carb slide springs based on the altitude your typically ride. I think Yamaha should fix this under warranty but that may never happen.
Here's the deal. They have springs for 0-4,000 feet, 4-8,000 feet and 8-12,000 feet. The springs retail for $39 a set ($44 with shipping). He guaranteed I'd gain a 1,000 RPM by this very simple spring change. All I can say is WOW! Now I can throw more weight at my primary clutch and not have to clutch for the lowest common denominator. Hey, for 39 bones and 30 minutes it sounds like a hell of a deal. Powder Blue