I am thinking about extending my apex to a 153 (extend or new rear suspension), and I was wondering would I have rubbing issues if I used a powerclaw 15x153x2.25 with 7 tooth 3" pitch drivers, and I'm guessing a drop bracket for the suspension would be needed.
Would it fit, or would I need to relocate the suspension and remove the tunnel protectors?
Would it fit, or would I need to relocate the suspension and remove the tunnel protectors?
To run anything taller than 1.5" lug, you will have to remove the tunnel protectors or make/get a notched track.
7 tooth 3" pitch x 2.25" is what comes stock on the Apex MTX, so yes, if you remove the tunnel protectors, you should be able to run this setup.
I don't think you are going to be very sucessful extending your stock 121" skid out to 153" no matter what you do. The reason I say this is because I (personal opinion) do not like to use rail extensions longer than 7.5". With a 7.5" rail extension, that brings you out to a 136". Now using a 136" with a 4" setback, you arrive at the length of 144".
If you do a search on setback, I think you will find the general opinion to be more than a couple inches of setback and your weight transfer gets way out of wack. You may not have the range of adjustability to get the weight off of your skis, and you run a greater risk of stabbing the front of your rails through the track. Then you have the whole issue of the track tightening during suspension compression when you do a setback. I won't go into is here, but if you search my posts, the topic was pretty well covered in the past. Member Lazy Bastard has some very good explanations of the pitfalls of doing a setback with a stock suspension.
I have the same sled as you, (07 RTX) and I have a 144" version of the ZX-2 suspension. Last night and this morning, I finished up technical plans for a custom designed mount plate system for the ZX-2 and our sled. It will have multiple sets of holes for various setbacks. Using the 144" ZX-2 rail extensions, I could theoretically run the following track lengths: 144", 146", 150", 151", 153", 154", 155", and 156". At 144" I would have 0" setback and the maximum for a 156" track would be a 6" setback.
I am hoping to get my prototype template burned out in the next few days. From there I plan on working out any bugs and getting a final set of plates created. I am fairly certain I can get the above described lengths to work out, and other lengths would be possible with different length rail extenders. I am excited to get this worked out because I can run my 144" ripsaw around here on the trails and have a large selection of deep lug tracks for out west or the UP.
I think your other opions are: get a skid out of a MTX, have custom rails made, retrofit a skid out of a different brand snowmobile, or use an aftermarket skid with or without setback.
If you have any other questions just ask.
7 tooth 3" pitch x 2.25" is what comes stock on the Apex MTX, so yes, if you remove the tunnel protectors, you should be able to run this setup.
I don't think you are going to be very sucessful extending your stock 121" skid out to 153" no matter what you do. The reason I say this is because I (personal opinion) do not like to use rail extensions longer than 7.5". With a 7.5" rail extension, that brings you out to a 136". Now using a 136" with a 4" setback, you arrive at the length of 144".
If you do a search on setback, I think you will find the general opinion to be more than a couple inches of setback and your weight transfer gets way out of wack. You may not have the range of adjustability to get the weight off of your skis, and you run a greater risk of stabbing the front of your rails through the track. Then you have the whole issue of the track tightening during suspension compression when you do a setback. I won't go into is here, but if you search my posts, the topic was pretty well covered in the past. Member Lazy Bastard has some very good explanations of the pitfalls of doing a setback with a stock suspension.
I have the same sled as you, (07 RTX) and I have a 144" version of the ZX-2 suspension. Last night and this morning, I finished up technical plans for a custom designed mount plate system for the ZX-2 and our sled. It will have multiple sets of holes for various setbacks. Using the 144" ZX-2 rail extensions, I could theoretically run the following track lengths: 144", 146", 150", 151", 153", 154", 155", and 156". At 144" I would have 0" setback and the maximum for a 156" track would be a 6" setback.
I am hoping to get my prototype template burned out in the next few days. From there I plan on working out any bugs and getting a final set of plates created. I am fairly certain I can get the above described lengths to work out, and other lengths would be possible with different length rail extenders. I am excited to get this worked out because I can run my 144" ripsaw around here on the trails and have a large selection of deep lug tracks for out west or the UP.
I think your other opions are: get a skid out of a MTX, have custom rails made, retrofit a skid out of a different brand snowmobile, or use an aftermarket skid with or without setback.
If you have any other questions just ask.
If I used an aftermarket skid would I be able to go without relocating the mounting position, other then drop brackets.
UncleRedBuck
Veteran
I have a 2007 Apex RTX and extended it to 144" using the rail extensions.
But I am running a Arctic Cat ZR skid.....I had to make my own drop brackets to accomodate the TSL but it was easy and would do it again.
But I am running a Arctic Cat ZR skid.....I had to make my own drop brackets to accomodate the TSL but it was easy and would do it again.
The track will fit just fine with the tunnel protectors removed and the 7 tooth 3" pitch drivers. I'm running the exact same size track/drivers as you except it's a Maverick.
If I were you I'd go a whole different skid - 121" to 153" is a huge rail extension. I have a Polaris Switchback skid with tipped up rails and it works great - I really like the 153" on the Apex.
If I were you I'd go a whole different skid - 121" to 153" is a huge rail extension. I have a Polaris Switchback skid with tipped up rails and it works great - I really like the 153" on the Apex.
