41 Tooth Cassette Sprocket

[Fabian]

Just got my hands on the "Mountain Bike Tools" 41 tooth cassette sprocket.

http://www.ebay.com/itm/41-Tooth-Cog-for-Mountain-Bike-Cassette-41t-Sprocket-/251408161635?pt=US_Cassettes_Freewheels_Cogs&hash=item3a89181b63

The photos clearly depict the difference between a 32 tooth cassette sprocket and the 41 tooth cassette sprocket.
Crunching the numbers, the 41T should give me 20.6% more pulling power than the largest regularly available cassette with a 34T largest sprocket.










For the disbelievers, here is an example of a giant sprocket at work, although it's a 42 tooth.

 

[Fabian]

The dished 41 tooth sprocket needed two 1mm spacers packed in between the 41T and the next smallest (34T) sprocket to give the correct centre to centre spacing for an 8 speed system.
The kit only supplies one 1mm and one 0.5mm spacer, so you will need to specifically ask for another 1mm spacer to be included in the package if using 8 speed cassette spacing.

The 41 tooth sprocket (in the photo) is attached to the hub in 8 speed configuration with the following sprocket sizes: 11 - 13 - 16 - 19 - 23 - 28 - 34 - 41
The cassette stack has been made from a mix of 8 speed and 9 speed sprockets. There is virtually no difference in sprocket thickness between 8 speed and 9 speed systems 1.85mm vs 1.75mm and it works perfectly so long as you use the correct spacers i.e 8 speed spacers on an 8 speed system.

8 speed uses 3.10mm spacers and 9 speed uses 2.54mm spacers.

The dished 41T cassette sprocket is a godsend because it allows you to maintain an effective 1:1 first gear ratio when using the much needed 40T front chainring sprocket supplied by Sick Bike Parts, but most importantly, it gives a significant (20.6%) increase in pulling power and hill climbing power when shifting the chain onto the Sick Bike Parts 24T front chainring; allowing you to haul serious payload up the steepest inclines.

Lets say you were maxed out hauling (a readily achievable) 400 lbs of payload up a 10% incline, now you can haul 482lbs up the same incline with the dished 41T sprocket - that's extra payload delivery and extra money in the bank.

 

[Fabian]

Upon trial assembly into the bike, i was not able to make the 41 tooth cassette sprocket work on the SRAM type 1 rear derailleur as the top jockey wheel would hit the sprocket, regardless how much the rear derailleur was pulled back. The most it would handle was a 38T sprocket with the B-stop wound all the way in.
Interestingly, the SRAM type 2 rear derailleur use different geometry for the top jockey wheel position, enabling it to shift onto a 41T sprocket.

I am going to modify my rear hanger by cutting it in half and welding it back together with 13 millimeters of fill, thereby extending the length; allowing a type 1 derailleur to comfortably clear the 41T sprocket.
For now, the 38T will have to do, giving me the custom sprocket stack of, 38 - 34 - 28 - 23 - 19 - 16 - 13 - 11

 

[Fabian]

New developments with the Mtbtools 41 tooth cassette sprocket.

Scroll forward to 1:28 on the video.

 

[MotoredSnowbike]

What is the yellow cog thing behind your derailleur cable? Also what kind of chain tensioner setup are you using on your chainstay there?