Do you have to change gearing if you go 121-144

prozac500

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Did anyone go from a 121-144? If you did, did you switch the gears in the chain case and the chain? I heard that the gearing is different on the MTX phazer.
 
You will need to gear down... How much depends on what model your 121 is. FX/RTX is 18 tooth... you need to be atleast here.... if not lower.
 
Yoo low is not always a good thing. A friend of mine has a Mtx and when he really pushes his machine he hits the rev limiter. Whereas on my phazer gt I've never done that. You have to remember you are sacrificing speed for torque.
 
At what speed(i.e. MPH) is he banging off the rev limiter? If it is not at WFO throttle, then I would think it is more of a clutching or belt/drive train maintenance issue than a gearing issue. If it is at WFO, then he must be trail riding his mountain sled at > 65-70 MPH.
 
Usually happens when hes in deep powder and really pins it to get out, or when he tries to do a wheelie off a bank.
 
PattyJack said:
Yoo low is not always a good thing. A friend of mine has a Mtx and when he really pushes his machine he hits the rev limiter. Whereas on my phazer gt I've never done that. You have to remember you are sacrificing speed for torque.

Yea but I am not gearing it to make it faster, I am trying to gear it so it's the same gearing as the MTX because I am long tracking it.

I think RedPhazer is right That dose sound like a clutching problem.
 
I would personally go with a 136" track. But yes it is also a clutch adjustment problem.
 
Prav said:
You will need to gear down... How much depends on what model your 121 is. FX/RTX is 18 tooth... you need to be atleast here.... if not lower.

Do you know how much I would have to gear down for the GT?
 
I have FX gears and chain if you need them.
 
scmurs from oftracing.com he sad he could make me some and tracks usa has them.

woolyviper
I don't know if the FX gears will work or not. But that is a good idea.
 
"Do you know how much I would have to gear down for the GT?"

The GT comes with a 20 tooth top gear. It probably won't pull like you want... I'd go with the 18 that Wooly has.
 
Prav said:
"Do you know how much I would have to gear down for the GT?"

The GT comes with a 20 tooth top gear. It probably won't pull like you want... I'd go with the 18 that Wooly has.

How would that work because he had to gear down for 136 would'nt I have to gear down a little bit more for my 144.
 
Rule of Thumb:

The more track you're trying to pull the lower tooth gear you should use. This will create more torque to pull your track at the bottom end like it should (you will sacrifice top end speed). If you are running stock GT gearing get rid of it and atleast drop to the stock FX/RTX 18 tooth top gear. This will be a good start and work through your clutching for the rest. If you're still not satisfied change the top gear again.
 


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