Jack_Shaft
TY 4 Stroke Junkie
Does anybody make a 121" to 144" conversion kit for the standard 2003-2005 RX-1?
I would like to build a "crossover" sled from my 2003 RX-1 and 136" is just not enough of a footprint for the riding I do. I guess rail extensions and a tunnel extension is what I'm looking for.
Any ideas? Mountain Performance?
-JS
I would like to build a "crossover" sled from my 2003 RX-1 and 136" is just not enough of a footprint for the riding I do. I guess rail extensions and a tunnel extension is what I'm looking for.
Any ideas? Mountain Performance?
-JS
Turbo Tim
TY 4 Stroke Master
Jack_Shaft said:Does anybody make a 121" to 144" conversion kit for the standard 2003-2005 RX-1?
I would like to build a "crossover" sled from my 2003 RX-1 and 136" is just not enough of a footprint for the riding I do. I guess rail extensions and a tunnel extension is what I'm looking for.
Any ideas? Mountain Performance?
-JS
How about this ? http://www.teamfast.com/m136.html

Jack_Shaft
TY 4 Stroke Junkie
I have a lightened Expert X right now, so I'll probably stick with that... I guess the tunnel extension is what I'm more concerned about, would like to buy rather than fab a 144" version.
-JS
-JS
Go with Expert rail extensions and a Hartman tunnel extension. 

BlgsRX-1mtn
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Mountain performance does have a 121" to 144" extension kit. It comes with the rail extensions, tunnel extension. Buy the track and all and save (unless you allready got a track). Here is my MPI 151" to 162" extension kit. Put it in Sat/Sunday and polished it up yesterday. 8)
The fit was spot on; I didn't have a single problem getting the holes to line up.
The fit was spot on; I didn't have a single problem getting the holes to line up.

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BlgsRX-1mtn said:Mountain performance does have a 121" to 144" extension kit. It comes with the rail extensions, tunnel extension. Buy the track and all and save (unless you allready got a track). Here is my MPI 151" to 162" extension kit. Put it in Sat/Sunday and polished it up yesterday. 8)
The fit was spot on; I didn't have a single problem getting the holes to line up.![]()
How strong is it? Can you lift the sled by the bumper?
I like the way the angle follows the tunnel instead of being flat like the OEM extensions Yamaha uses.
Jack_Shaft
TY 4 Stroke Junkie
I agree about the angle issue, the tipped-up extemsion looks far superior. In Yamaha's defense, they probably didn't have a choice but to use a flatter extension due to tail lamp visibility and/or tail-flap-distance-from-floor restrictions.
The aftermarket has so much more freedom...!
-JS
The aftermarket has so much more freedom...!
-JS
Turbo Tim
TY 4 Stroke Master
Phantom said:BlgsRX-1mtn said:Mountain performance does have a 121" to 144" extension kit. It comes with the rail extensions, tunnel extension. Buy the track and all and save (unless you allready got a track). Here is my MPI 151" to 162" extension kit. Put it in Sat/Sunday and polished it up yesterday. 8)
The fit was spot on; I didn't have a single problem getting the holes to line up.![]()
How strong is it? Can you lift the sled by the bumper?
I like the way the angle follows the tunnel instead of being flat like the OEM extensions Yamaha uses.
I towed a skidoo out of the mountains about 10 miles at least with that same bumper / extension - IT's Strong!
BlgsRX-1mtn
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It is strong enough that I had the sled suspended from the rafters of my garage while installing the front of the track and drive axle. Why Yamaha doesn't angle the tunnel up from the factory is beyond me. The other OEM sleds have an angled tunnel.
Only reason I can come up with is cooling. The tail light is still plenty visible with my 162". My wife's RMK has the edge coolers on the running boards, rear exchanger and front radiator and a kicked up tunnel from the factory.
With a kicked up tunnel the snow is allowed to escape somewhat out the back rather than traveling through the tunnel and out the front. That is also the reason alot of mountain guys do a drop and roll on the chain case when putting a higher profile track or larger drivers. The snow exiting the front causes a restriction similar to hydrostatic lock which robs you of power and speed if there isn't enough clearance between the bulkhead and track lugs. That is also why alot of mtn guys run cut off flaps or none.
Only reason I can come up with is cooling. The tail light is still plenty visible with my 162". My wife's RMK has the edge coolers on the running boards, rear exchanger and front radiator and a kicked up tunnel from the factory.
With a kicked up tunnel the snow is allowed to escape somewhat out the back rather than traveling through the tunnel and out the front. That is also the reason alot of mountain guys do a drop and roll on the chain case when putting a higher profile track or larger drivers. The snow exiting the front causes a restriction similar to hydrostatic lock which robs you of power and speed if there isn't enough clearance between the bulkhead and track lugs. That is also why alot of mtn guys run cut off flaps or none.
Jack_Shaft
TY 4 Stroke Junkie
BlgsRX-1mtn said:Only reason I can come up with is cooling. The tail light is still plenty visible with my 162". My wife's RMK has the edge coolers on the running boards, rear exchanger and front radiator and a kicked up tunnel from the factory.
Key feature here is that the RMK's tail lamp is mounted with rubber grommets on the rear bumper if it's a late model Edge chassis sled. It was put there since the tail lamp was simply not visible if mounted conventionally in the seat bun, as it usually is.
-JS
BlgsRX-1mtn
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Jack_Shaft said:BlgsRX-1mtn said:Only reason I can come up with is cooling. The tail light is still plenty visible with my 162". My wife's RMK has the edge coolers on the running boards, rear exchanger and front radiator and a kicked up tunnel from the factory.
Key feature here is that the RMK's tail lamp is mounted with rubber grommets on the rear bumper if it's a late model Edge chassis sled. It was put there since the tail lamp was simply not visible if mounted conventionally in the seat bun, as it usually is.
-JS
It's not an edge chassis (IQ chassis 900 RMK) but, yea the tail lamp is mounted to the tunnel at the back (not the rear bumper). Like I stated though my tail lights are visible by about 2" with no load on the sled. You put the load of a rider on there and they are even more visible. This is with the longest tunnel extension made for the RX-1.
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