What's the best ALL AROUND RX-1 Mountain gearing?

[Frostbite]

Thanks TRXSTER.

I think I'll try the 21 x 42 first before I buy the 20 tooth upper gear.

Isn't there a gear vs. top end chart somewhere? It seems I've seen this before but it's based on engine RPM and 9 tooth drivers if I remember right.

Frosty

 

[HAMMER]

............. ..............

http://www.snowmobileworld.com/tools/index.php

 

[Frostbite]

Thanks Hammer. It's nice to see you on here again. How's Pop?

According to the chart with 8 tooth drivers and a 10,700 shift speed (a little high I know but my sled loves it):

20 x 40 = 95.09 mph
21 x 40 = 99.84 mph (stock gearing)

20 x 42 = 90.56 mph
21 x 42 = 95.09 mph

It looks like 21 x 42 is what I'm looking for right now.

Frosty

 

[HAMMER]

Pop is close to his maximum allowable tolerance......he can't wait for me to retire (1430 days to go).....so he can quit and collect his Social Security......lol

I’d be surprised if you can throw that 151 finger above 95mph (105-speedo) in anything but the coldest, lowest, hardest conditions you ride in… If you really want to get this figured out go back-to-basics… Mark your clutch and do some field-testing with different clutching and gearing in YOUR specific set of riding conditions… Gearing too tall is giving away torque that you could be using in the lower portion of your shift ratio (lower gearing = torque multiplication)… You want it as low as you can get it and still perform the way you want it to in YOUR specific set of riding conditions.

 

[Frostbite]

Thanks Hammer.

So a move east is planned in a few years huh?

Randy what do you think of the Skidoo 151 x 16 x 2.3" tracks?

I have serious considered putting one of these tracks under Old Betsy in place of the finger track. I took your dad's advice and trimmed my 2.25" finger track to 2.0" across the board.

How does track height affect ground speed?

Frosty

 

[Trxster]

I tell you, we were fighting to get through a trenched out creek crossing on Mt Baker. We had been through it a number of times basically had to do 1 sled at a time pushing/driving. We brought a buddy on his Rev with that track and he walked right up it and we were all pretty impressed!!!!


Rt

 

[HAMMER]

So a move east is planned in a few years huh?

Yep -- East of the Cascade/Sierra Nevada Range and West of the Rocky mountain Range.

Randy what do you think of the Skidoo 151 x 16 x 2.3" tracks?

I have no experience with the Doo-Doo track in an RX-1 application... You stated 70% trail, 20% boonies, 10% climb and you ride that high water content "Cascade Chowder"... There is no better track for those conditions than the track you're currently running.

I took your dad's advice and trimmed my 2.25" finger track to 2.0" across the board.

I do have experience with that........hooks hard with the right weight transfer don't it.

How does track height affect ground speed?

The effect it has is resistance... Having taller lugs is not the same as having a larger diameter tire in an automotive application... Think of it this way, the axel drivers (diameter) are the tire in a snowmobile drive train and the track is the road they drive on... That's why there is no place to input your track length and lug height in any snowmobile MPH formulas or calculators.

 

[Frostbite]

Thanks TRSTER and Hammer

Randy, we're east of the Cascades. I can always use a good TODO if you ever decide you need a change. I've got an E-8 doing now as an additional duty and I need him inspecting aircraft.

Frosty

 

[HAMMER]

I'll call ya at work........since we're both at work today.......

 

[Frostbite]

Thanks for the call Hammer. Let me know if you change your mind. I think I could hook you up.

Thanks for the forum tips.

Frosty