gearing down Rx1

LB You seem to be the gear down guru. I currently run a 23 38 in my RTX but have a 39 bottom that I was thinking if adding. I am going to run an XS 805 this year and have a secondary that will overdrive. I do a lot of lake running but I am not looking for just top speed. I do mostly 1000 to 2000 foot drags on snow and ice. I know it is not a big change but what do you think? I have a 1" track with good studs which hooks well. I think I will be at around 165 to 170 HP this year.
 
Lets say you're running nearly 15% more power... geared down about 2.5%, overdrive about 5% giving you about 2.5% more top end potential before you start to overrev. Now of course, 15% more power does NOT translate to 15% more speed, so you're probably going to run close here. I give you a 50% chance of overreving by putting in that 39 tooth gear. It should definitely help in the drags though....
 
Lazybastard is right on.

I have geared down my turbo sled 1 tooth to 23/38, running at 285 HP. A stocker benefits from gearing down even further than 1 tooth that's for sure.

In my '05 stocker I run 21/38, this sled is not geared for top end (I have my turbo for that) but for the tight and twisted trails. I even haul timber out of the forest with the '05, it pulls whatever I can load into my timber sled, no problem. Throttle response is vicked on the '05.
 
LB where does the speedo end up on this ? I know the stock setup the speedo is off like 10-15% when we gear down what happens to the reading on the speedo? I would like to correct it if I can. I am running 23/38 with 8 tooth drivers.
 
Speedo reading is taken off the drive aksel so gearing down will not affect speedo readings. To correct this your can grind off 1 tooth of the speedo pickup, this will get you close, still reading a few % high.

The 8 tooth drivers (if driver outer diameter is less than stock) will affect the speedo readings. How much I don't know, have to do the math on this one
 
Mikey said:
LB where does the speedo end up on this ? I know the stock setup the speedo is off like 10-15% when we gear down what happens to the reading on the speedo? I would like to correct it if I can. I am running 23/38 with 8 tooth drivers.
With 8 tooth drivers, your reading will be considerably more off than stock.

As for it being 10-15% off stock, nope, not THAT far. Some people will have readings that are way off, but thats because the track slips. I once saw a reading of 135 and I wasn't going more than about 50. I've also had a reading on the gun of 118 with a speedo reading of 125 --- thats less than 6% off, which is more accurate than my truck. My truck is actually 7% off (also reads high).
 
speedo

yep with the 8 tooth they would be even farther out but with 10 tooth drivers there dead on ;)! and you even get a better track angle and the speed off the trail in the snow picks up . :jump:
 
gear

yes i did before going to the 10 tooth drivers and two teeth was very close . with in 1-2 mph . after installing the lager drivers i had to put the stock gear back and i was a little closer yet . and i had to gear down for the drivers as well 24-42.
 


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