One thing that has been a thorn in the side of my Kona Sutra experience was the front derailleur. When I had a mountain bike I converted it to a single narrow wide chainring in the front and got rid of the front derailleur completely. It changed my whole mountain biking experience to something more positive, not having to think about when to go to the small chainring, doing that in the wrong section could prevent you from going back to the large for a long time. And the occasional involuntary downshifts that happened were not fun either.
So, after riding quite a bit of roads and trails I decided to upgrade my Kona Sutra to a single chainring system this winter.
Disclaimer
I bought this product myself and this is my opinion on them. I am in no way affiliated with the manufacturer of this product. I like to link to other sites and I am not paid for that.
Gears
Before anyone starts commenting on x3 vs x1 setups, I know that this is not ideal for everyone. A lot of touring people seem to favor the 3 chainring design and I am sure that it has its place. Everyone should opt for the bike configuration that they think is the best for their needs, no need to bash others. Now that that is out of the way, lets start to look at the gears of the two drivetrains in question here.The 2020 Kona Sutra Ltd comes equipped with SRAM Rival x1 drivetrain, the reason I did not want to go that way was because it is only 11 speed and I wanted the 12 speed SRAM Eagle as it is on the market.
A quick comparison on gear range between the current setup and the SRAM Eagle setup
| Wheel diameter (m) | 0,70 | |||||||
| Wheel circumference (m) | 2,20 | |||||||
| Cadence | 90 | |||||||
| Large chainring | Small chainring | Large cassette | Small casette | Lowest gear ratio | Highest gear ratio | Lowest km/h | Highest km/h | |
| Shimano Alivio 3x9 | 48 | 26 | 34 | 11 | 0,76 | 4,36 | 9,08 | 51,82 |
| SRAM Eagle 1x12 | 32 | 50 | 10 | 0,64 | 3,20 | 7,60 | 38,00 |
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| A visual comparison of the gears between the Kona Sutra original setup and the SRAM Eagle (Click on the picture for a bigger version) (tool used: ritzelrechner.de) |
What I am gaining
- Even lower climbing gear then the 26/11 on the original setup
What I am loosing:
- The going fast gears, but honestly I seldom use those and even less when the bike is fully packed. If it is a downhill section, I tend to rest when the speed starts to get above 30 km/h, so that I can tackle the next uphill that is bound to show up soon.
- Longer steps between gears
To clarify the last bullet of longer steps between gears, let's look at another picture to visualize the difference.
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| Top line, the original 9 speed casette on the Kona Sutra, lower line is the SRAM Eagle cassette (Click on the picture for a bigger version) (tool used: ritzelrechner.de) |
The 9 speed 11-34 cassette is able to put the gears in a tighter space (smaller steps between gears) then the SRAM Eagle 10-50 cassette is able to. From what I understand, this seems to be one of the key issues that people have with the current SRAM Eagle.
For my uses, I think that I should be able to live with the difference. The biggest steps seem to be when going to the lowest and highest gear, normal riding is usually done somewhere in the mid-range and the cogs there seem to be better packed. Or, I just have to live with the pain until I get strong enough to handle it.
- Cycling tips - Beyond the big ring: Understanding gear ratios and why they matter
- Wikipedia - Bicycle gearing - Gearing Range
- ritzelrechner - Gear Calculator
What I ended up buying
To convert the Kona Sutra to SRAM Eagle I ended up buying a lot of stuff, and it got a tiny bit more expensive then I originally thought it would be...
I went with the SRAM GX version of the Eagle drivetrain. There was a cheaper one, the NX, but it went from 11-50 and I read some review stating that the cassette was not that high quality, so I got scared and went for the GX that seems to have gotten better reviews. The X01 and XX1 are out of my budget.
As I got the DUB groupset, I also needed a new DUB bottom bracket that fit into the BSA threading of the frame. And a the SRAM Eagle is originally built for mountain biking, I needed to find bar-end shifters that were compatible, and luckily there are, from microSHIFT. They also seem to support other obscure new 12 speed drivetrains like the one from Shimano.
And as I threw the front derailleur in the trash, I needed to plug the bar-end on the left side. I have some nice plugs on my racer with allen-key tightening so I went with similar for the new setup. Works like a charm on the racer and never drops out.
Oh, and don't forget to buy new handlebar tape as you need to remove the old one to get to the cables for the bar-end shifters.
As I got the DUB groupset, I also needed a new DUB bottom bracket that fit into the BSA threading of the frame. And a the SRAM Eagle is originally built for mountain biking, I needed to find bar-end shifters that were compatible, and luckily there are, from microSHIFT. They also seem to support other obscure new 12 speed drivetrains like the one from Shimano.
And as I threw the front derailleur in the trash, I needed to plug the bar-end on the left side. I have some nice plugs on my racer with allen-key tightening so I went with similar for the new setup. Works like a charm on the racer and never drops out.
Oh, and don't forget to buy new handlebar tape as you need to remove the old one to get to the cables for the bar-end shifters.
- SRAM GX Eagle Shifting Groupset 1x12 DUB 32Z. 175mm
- SRAM AM DUB Bottom Bracket English/BSA (Length 73mm)
- microSHIFT BS-SR-M12 Bar End Shifters SRAM MTB 12-speed compatible black
- BBB Cycling - ScrewOn BHT96
- Cinelli - Mike Giant Velvet Ribbon Black/White
That's all, right? Wrong!
Turns out to be able to fit that huge 10-50 cassette on the back-wheel you need a SRAM XD Freewheel Body. And, as the hubs that are originally on the Kona Sutra are of a brand called Formula, it is almost impossible to find the correct one (if there exists one).
So I ended up buying a new wheelset, something that I thought of doing ever since the 3 day escape we did in May as the front wheel wobbled and it still does even after my local bike-shop tried to fix it and after that I tried to true but the wobbling persisted. All bikes in that price segment ship with shitty wheels, just have to live with it : )
So..
I think the NX would have fitted the Shimano freewheel hub, but well.... I was doing this so I did not want to change to the NX just for this. In the end I would have bought new wheels anyway, it's just the way I tick, I like to upgrade my bikes and enjoy that process almost as much as I enjoy riding them.
Removal of old parts
In this section I'll just go through the things that stopped me for a bit.
Chain
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To remove the chain, use a master link tool and just open the missing link. I did not have a tool when
I started out so I tried to break the chain but my chain-breaker did not manage to do it.
Had to drive into town and buy a master link tool and the link just opened in less then a second. Well worth the 15€.
Bar-end shifters
For removal of the bar-end shifters:
- Put the lever in its down position
- Remove the flat-head screw and its nut (on the other side)
- Remove the lever
- Use an 6mm hex (allen-) key and turn it clockwise to unmount the shifter
Pedals
Pedals usually require a bit of violence to come of the cranks. I use a rubber hammer.
Bottom bracket
Ah, this one beat me. The drive (right) side was quite easy to remove with the help of a rubber hammer on the bottom bracket removal tool. But the left side did not move even with rubber hammer force applied.
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| Bottom bracket removal kit. A bottom bracket tool and an extension bar |
- Apply lubricant that is able to penetrate the threading, I used WD40.
- Wait, I went and ate dinner and watched a movie.. 3 hours maybe
- Use a cheater bar, or something to extend the tool. I used a long metal pipe. The handle of your tool must be able to fit inside of the pipe.
- Place the frame on the floor and stand on it, use one hand to hold the tool in place and the other to apply force on the cheater bar.
- Finally the bottom bracket moved
Handlebar tape
Make sure to document where the shifter cable goes through the old handlebar tape as you will have to make sure that it will come through at the same place after you have put in the new 12 speed shifter.
Additional resources on removal of components.
- Jon's Cycling Log - How To: Remove Bar End Shifters
Installing of all the new parts
So fingers crossed all this new stuff works together.Wheels
Ah damn. The body I got was the XD-Race and SRAM Eagle is XD compatible. Luckily the body came with a spacer that made it XD compatible.
Changing the body was a pain, looked through a lot of youtube videos where they just popped the body out. Turns out that's the way to do it, I just was too weak to do it the first 30 times. Just fingers and a long pull on the whole body and it will pop out from the Mavic 360 freehub.
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| Using torque wrench to tighten the screws that hold the disc on the wheel. In my case it said 10Nm per screw. Make sure that you read you manual for the wheel you use |
Cassette
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| Tightening the SRAM Eagle GX Cassette with a normal cassette tool. (Same that I use for Shimano) |
My torque wrench only goes to 24 Nm, so I had to just tighten it by feel. I.e. as hard as I could get it. This is the same tool I use for Shimano cassettes, so at least they are compatible on that part.
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| Comparison of SRAM Eagle GX cassette with a Shimano 9 speed cassette. The Eagle is a monster in comparison |
Bottom bracket (BB) and crankset
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| SRAM DUB BSA Compatible Bottom Bracket Tool |
Be sure to reference MTB and Road Cassette and Chains PDF linked below to see what spacers you need when installing the crankset.
Rear derailleur
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| Almost completely installed SRAM Eagle on a Kona Sutra, only thing left is to install the wire to the rear derailleur. |
After that, install the chain. You will need a chain breaker. Be sure to look at MTB and Road Cassette and Chains PDF linked below to find out how to measure the chain correctly before you use the chain breaker.
When you have the correct length, install it on the 10 cog on the cassette and through the rear derailleur and install the power lock.
At this point it is good to measure the length of the chain so that you can check it for wear later. 11 of links on my chain was 132 mm. SRAM recommends that you change the chain when it is 0.8% elongated. In my case 1 mm. If in doubt use a longer bit of chain to measure.
For adjusting the rear derailleur, I'll just link to Park Tools, they have a nice guide on how to do it. Be sure to use the SRAM Eagle mounting guide that was in the nice SRAM Eagle box, the red plastic one to make sure that the distance is correct between the cassette and the first guide pulley in the derailleur.
- Using the SRAM Eagle mounting guide
- MTB and Road Cassette and Chains
- Park Tools: Rear derailleur adjustment
Bar end shifter
The new microSHIFT bar end shifter was pretty much identical to the old Shimano ones, meaning that you just put it in the bar end and tighten it by counter-clockwise with an hex key.
- Jon's Cycling Log - How To: Remove Bar End Shifters
Wrapping new bar tape
Before you start, make sure that the cable housings are taped to the the bars, I use electric tape. The original tape was not that good and I ended up redoing it all.
After that, just wrap the tape. Begin at the bar-ends and work your way inward.
Make sure you check if you bar end tape has a preferred wrapping direction, I didn't and did it the wrong way. Total failure and as I was too confident I didn't test without removing the plastic cover of the glue.. Long story short, had to order another roll to cover that mistake.
I usually tape the start and end of the bar-tape with electric tape just to make sure that it doesn't start to unravel.
- Total Women's Cycling - How To: Wrap Bar Tape
That's it!
There were quite a lot of stuff to install but I think I've covered the bits that stopped me in some way or the other. I.e. bits that I did not find straight forward.
Weight
One of my goals with this was also to get rid of some weight. With all the stuff on the bike, lock, surly front rack, pedals etc the bike weighted in on excessive 16 kg before doing the upgrade. Only the front wheel with tyre was 1.9 kg.So, with all other stuff still on the bike, the number to beat with the new components listed above is 16 kg.
Total weight before upgrade: 16 kg
Total weight after upgrade: 14.9 kg
Total change: 1.1 kg
Front wheel with tyre before upgrade: 1.9 kg
Front wheel with tyre after upgrade: 1.6 kg
Front wheel change: 0.3 kg
I guess the majority of the weight loss comes from the new wheel-set.
Test ride
As I am not 100% fit at the moment due to a longer hospital stay this fall and failed Whipple surgery 3 weeks ago that still bugs me, I will not do any long test ride at this point. I mean, I've lost all my muscles and it will be a long process to get back in shape.But, a ride around the block should be possible and encouraged by my doctor so that is what I'll do.
In total 4 km flat, 1.5 km on asphalt and the rest on dirt roads.
The bike handles very nice, pedaling is smooth and switching gear works good.
Can't really comment on the bike weight as I have lost 25 kg myself since last outdoor cycling, but the wheels were straight and didn't wobble as the original ones did.
And do I love the freewheel sound of the Mavic 360 hub? Yes, yes I do!
Thoughts and conclusions
To my surprise the SRAM Eagle was quite easy to install, once you have all the tools (that I did not have when starting out).I really like the SRAM PowerLocks compared to the Shimano pins that you have to install using a chain-breaker. It's such a pain to do.
Note for future is to get another torque wrench for the high torque bits like the cassette installation or the bottom bracket and crankset. At the moment I just figured that 50 nm is me using what force I can muster and when it stops it stops. Getting a torque wrench that goes from 20 nm and up to at least 60 nm would be a nice complement to my current torque wrench that goes from 2 nm to 24 nm.
It took me 2 months to complete the upgrade, but mostly as I really don't have the strength to work in longer stretches at the moment and the fact that I have been at the hospital quite a lot during that time. In real time, it might have taken a couple of days. So maybe a little big of a project for one weekend but maybe OK for two?
Would buy again.
Disclaimer
I bought these products myself and this is my opinion on them. I am in no way affiliated with the manufacturer of this product. I like to link to other sites and I am not paid for that. Feel free to share on social media if you found anything in this post helpful! That would mean a lot for me!
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