Cotic Solaris - Hope Single Speed hub - 1x6 gear conversion

[divernick]

 

It's started. I took the first 9 speed cassette I could find and ripped it apart. It's a 12-25 road cassette. The ratios on the bike now are 25-23-19-17-14-12. The RD is a Dura Ace 7800 mech. Deore 9 speed shifter. Next steps wil be installing the shifter cable and chain. Then we'll see if this will work. Climbing some of the tougher hills on 34x25 might be "interesting" so I'll definitely be rethinking my ratios once I'm happy everything works as it should. Although as a SS rider I know that 34-20 can climb anything but the very steepest hills.

[The MTBer]

Cool idea, I was thinking of something like a 3 speed, for a little climbing and the SS feeling if you hit high gear. Something like a 32 and a 24/18/16 or a 23/17/13 (from an old 9 speed) or something.i think you can use the SS spacers on the freehub I wish I have money for a bike to play with.

 

Edit: the ratio combination

[V12man]

Nic - I am looking for a set of 8 speed STI levers - keep a lookout would you - thanks

[J∆kk∆ls]

Im curious to see how the shift from 19 to 23 goes. It seems like quite a jump.

Although Im a noob when it comes to building a Frankenstein, so maybe I should keep quiet and watch.

 

Good Luck

[Ryanpmb]

Im curious to see how the shift from 19 to 23 goes. It seems like quite a jump.

Although Im a noob when it comes to building a Frankenstein, so maybe I should keep quiet and watch.

 

Good Luck

 

Loads of guys fitting 42T sprockets on their range extender setups... 36 - 42 jump...

[Gandalf]

Cool project.

 

I'm interested in the shifting specifics. Will check whats up when  its done. 

[divernick]

A quick note with pics to follow.

 

I used a 9 spd Deore rapid fire shifter and a Dura Ace 7800 10 spd RD. It shifts great. I settled on the following ratios: 12-15-17-19-23-30 and there are no issues. Low limit screw keeps the chain on the largest cog and the mech out of the spokes. Plenty of pulley to cog clearance as well - which was my main concern. And it shifts fine from 23 to 30. Pics soon.

 

Oh yes, the Cotic allows for full length shifter cable outer use. [emoji106][emoji106][emoji106]

[johanpre44]

1x6 gearing, using a 10speed rd and 9 speed shifter. And it shifts perfectly! Nice!

 

Did you mention what chain you use?

[lefthecountry]

yeah i agree, if you running only 6 spd a thumbie would be ideal...

 

Now im wondering... Ive recently seen the SRAM DH X1 7spd cluster, i wonder if that would fit on an SS hub???

 

That comes with its own 7 spd shifter and special cassette...

Hmmm

 

*edit

 

I see it only works on their XD driver, damn

 

 

Pretty sure that one only fits on some specific Sram hubs. And it was crazy expensive. What the owner of this bike is doing is a much better idea.

 

I have actually condisdered doing this too. Running a single speed hub with 6 cogs means that the flanges are further away from eachother, creating a stronger rear wheel, also with less flex.

 

I would even like having less gears, but keeping the same reach of a 9sp cassette (for example 36-11, with less cogs and bigger intervals). Main reason for me would be that I'm from The Netherlands, a very flat country. Our XC trails usually don't exceed 50m in height difference, causing short climbs and short descends. Because of that having less cogs with the same reach would mean much faster shifting between gears. 

 

But even here in South Africa I wouldn't mind this set up. I love minimalistic bikes. Usually minimalistic means much less maintenance, less costs, and a more pure ride where less can go wrong.

 

 

About the non-clutch rear derailleur on a n/w chain ring. I currently ride a 105 road derailleur in the back since my XTR broke. I only had like 3 xc rides with it, so it's not a great test, but it hasn't dropped yet.

[Flowta]

Glad the project worked out. If you wanna add a clutch at a later stage, use a 9 speed SRAM shifter and a 10 speed Shadow + derailleur (XT,SLX,DEORE,etc.) with a 6mm spacer.

 

Google SRAMano, there's also a thread on thehubsa about it.

[divernick]

I'm using the cheapest 9-spd chain I could find - a SRAM PC-951.

 

I'm going to look for a 11-T cog to use as smallest gear for max top-end....

[divernick]

Glad the project worked out. If you wanna add a clutch at a later stage, use a 9 speed SRAM shifter and a 10 speed Shadow + derailleur (XT,SLX,DEORE,etc.) with a 6mm spacer.

 

Google SRAMano, there's also a thread on thehubsa about it.

 

I've seen that conversion. I have a 10-speed SLX shifter and 10-speed cassette so if I go clutch all I'll need to buy is the RD.

[divernick]

The problem with using a SS hub is that some Shadow RD's get into the spokes....so I may not be able to use one in this setup....

[SimpleDom]

What a cool idea. And no better frame to do build it around. I'm cotic smitten right now. It's funny... You read all this stuff about derailleurs matching shifters matching brand matching speeds. Here you just bang it together and it works!

[divernick]

[divernick]

I found a limitation. I can't use a 11t cog. The way the cog normally goes onto a cassette leaves it proud of the free body. This brings it too close to the dropout. The RD can't operate there. Oh well. 12t smallest cog it is. With a 34t chainring It's still similar to someone running 32x11 so I'm not really worried about top end. 30t large cog should be fine too.