novecho_delta

Hello,
I am new to the world of bike modification and I've recently purchased a used Specialized Crosstrail. I am currently turning it into a trekking/hybrid/all-purpose bicycle. However, I am getting stuck on which drivetrain I should get. I am looking at a mountain bike rear derailleur and cassette for those million-tooth lower gears, but paired with a 2 or 3-by chainring so I don't outperform the gears when speeding down a hill.

Is it possible to, say, have a 11 speed Box Two rear derailleur and cassette, paired with a 2 or 3-by chainring from Shimano or Sram? Are there any compatibility issues with making a custom groupset?

Thank you for your help.
- novecho_delta

CliffordK

You can mix and match parts somewhat.

Here is a good summary of shift ratios:
https://en.wikibooks.org/wiki/Bicycl...ing_Dimensions

I don't see any notes on the Box Two whether it is Shimano or SRAM compatable (1:1 for the latest MTB).

You also need to look at the derailleur specs:

Maximum cassette size:
Chain Wrap ((largest rear - smallest rear) + (largest front - smallest front))

What shifters are you planning on using?

jimc101

Ratios; would be looking at what you currently have and what you are looking at, and working out what/if there will be any benefit in doing any changes or different changes from what you currently looking at before doing anything.

For the bike in question, a SpecailizedCrosstrail as Hybrid as you can get, going on current specs(you have given no indication of the year, or if it's just a frame or complete bike), it already has a 28t front smallest, and 32t rear largest, how much lower do you want to go!

Just mentioning 'speeding down a hill' indicates you need to do a lot more research, and would probably be best sticking to what you have before throwing money at specialist components when you don't know what benefit they are going to give you, and if what you currently have will work.

fietsbob

You OK with A mixing shifters ? matching with shifter & the derailleur on the other end of cable.. or B using a friction shifter for the front derailleur ..


(and C _ heretical _ Alfine 11 speed IGH and a 2 pulley chain tensioner , to allow 2 chainrings, spreading the ratio range...)






...
11 speeds is the cog count in the back, on the front its 1,2, or 3 only adaptation .. the 11 speed chain is thinner so the gaps between chainrings are thinner..
so thin chain wont fall between them 10 not that much different.





...

novecho_delta

I bought my bike from a colleague. He had no idea what model year it was as he had inherited it from a friend. After looking at the bike and doing some research, I believe it is a 2009 Specialized Crosstrail, although I'm not sure. It came with a Shimano Deore (not sure which generation) front and rear derailleur (and matching shifters), unbranded v-brakes, and an RST Neon Pro 75mm front fork. The front and rear derailleur, front fork, wheels, brakes, and cassette are all useless at this point, so it's pretty much a decorated frame.

When the drivetrain was working, the lowest gears were extremely low, which was fantastic. I definitely want to replicate that. I don't have any experience with 1-by and 2-by drivetrains, so I thought I would ask around to see if they would work on a trekking/hybrid style bike. My local bike shops don't work with many trekking or hybrid bikes, so they recommended I ask around. If possible, I would like to run a 1-by-11 mountain bike drivetrain for the mechanical simplicity, but I don't know how good that would be when sprinting. What kind of performance would I get with an 11-speed 11t to 46t (or similar) cassette in the rear and a 34t or 36t chainring in the front? Would that give me a wide enough range?

fietsbob: I am fine with mixing shifters. I don't love friction shifters, so I'd rather avoid that option if possible.

Thank you all for your help.
- novecho_delta

calstar 

I don't get this, there are no magical/mystical/unobtainiun parts on trek/hybrid bikes, sounds pretty strange to me especially since nearly all shops are struggling just to survive, and these guys are sending your business away?? Where do you live?

regards, Brian

fietsbob

I'd remind that a bike has a brand name on the frame, as a result of a contract.. now many names go to few actual factories

Now Specialized is made in TW by Merida , who owns a % of the company , then , shipped to distribution ware houses near container ports

every other component part is bought in big lots from a component factory.. some get designed just for one client..

If it is brand labeled as you say " an 11 speed Box Two rear derailleur and cassette" someone made it and rebadged it for who ever the Box company Is.

.I've never heard of the brand.






....

alcjphil

I have questions: You state" When the drivetrain was working" , but you also have said, " The front and rear derailleur, front fork, wheels, brakes, and cassette are all useless at this point" That is a description of a whole lot of expensive components that might need replacement. Before embarking into a black hole of upgrades, please try to figure out which of your current components is actually non functional

novecho_delta

calstar - I'm located in Denmark. You would think that there would be more of a trekking community here, but not from what I can see.

fietsbob - Box Components is a small US company that primarily works in BMX parts, but recently branched out into mountain bike parts. I believe they make all of their components in-house.

alcjphil - The drivetrain was never really working. When I inherited it, the 9-speed cassette only had 7 working cogs, and the 3-ring crankset only had two working chainrings. Additionally, the rear derailleur would stick in place and the spring in the front derailleur rusted and broke over time. The wheels are worn through to the indicators and the front fork is rusted shut. At this point, the bottom bracket is probably worth replacing as well. The V-Brakes are outdated and crappy and if I'm replacing everything, I might as well spend the extra bit and go for disc brakes. I'm basically starting with a clean slate.

I did ride the bike for some time (against the advice of my preferred bike shop) until my derailleur hanger broke (somehow) and sent the rear derailleur up and into my wheel, which ruined both my derailleur and some of my spokes.

Thanks.
- novecho_delta

Darth Lefty 

fietsbob

https://www.boxcomponents.com/? weird company they want personal information just to see the site..


How old are you?
I'd wait till after I saw the production machinery at work, in person, , if I were you .. there are Flat Earth believers..







​​​​​​​....

novecho_delta

They require personal information? Where? I have no problems accessing the site and I haven't put any personal information in. What are you seeing?
Box caught my eye when I was looking at durable, efficient drivetrains. Their components come with a lifetime warranty that backs breakage and manufacturing defects, according to their website. GMBN, Pinkbike, and a handful of independent reviewers have reviewed their drivetrains and other components and the reviews have been mostly positive. Plus, I am a fan of supporting new, small companies, which is exactly what Box Components is.

Darth Lefty - While the idea of a custom drivetrain sounds fantastic, I can't afford to roll the dice and potentially purchase incompatible parts, unfortunately. Do you have any experience running 1-by mountain bike drivetrains on a trekking bike?
- novecho_delta

TimothyH

The Specialized Crosstrail has no provisions to mount a disk brake caliper on the frame.

fietsbob

Magura, Germany makes a hydraulic rim brake that works great on frames with V brake posts

FWIW..

buy a new fork for disc brakes , or buy a new bike like you now want.. with the features you wish were on yours..







...

novecho_delta

What's your source? Could you be talking about a different model? Unless I'm horribly mistaken (which is very possible actually), I have an Intl. Standard disc caliper mount on the rear of my Crosstrail. I would show you a photo but this forum apparently doesn't like new users and consequentially has disallowed me to link to photos.

I'm thinking of putting a Rockshox Recon RL on the bike, as it's one of the only higher-end 1 1/8" XC forks available that I could find, and obviously the Crosstrail doesn't have a tapered head tube. I won't have an issue fitting 700c wheels to a 29" fork, will I?
- novecho_delta

Darth Lefty