Mullet drivetrain conversion

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OP
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rivers

rivers

How far can I go?
Location
Bristol
Do you mean lower/higher gears as in gear ratios, or as in lower (smaller) sprockets/higher (bigger) sprockets?

The chain on my modded CAADX drops nicely down to smaller sprockets, but sometimes needs a little extra encouragement in the opposite direction. Once in whatever gear, it stays there, and doesn't make any unusual noises. That tells me that the indexing is almost exactly right, but not 100% so.

Gear ratios. So won't move back down the cassette to any smaller cog once I've shifted up the cassette.
 

ColinJ

Puzzle game procrastinator!
Gear ratios. So won't move back down the cassette to any smaller cog once I've shifted up the cassette.

Maybe excess friction in that cable loop?
 
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T4tomo

Guru
Maybe excess friction in that cable loop?

agree sounds like friction problem somewhere.
Could also be at interfaces to internal runs and outers or outer to shift-mate. Dont be afraid of a larger loop (despite appearances) what you want is a smooth eve arc and a nice entry to the shiftmate
 
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OP
OP
rivers

rivers

How far can I go?
Location
Bristol
Update: I can now move up and down the cassette. I still need to index the derailleur, currently only getting to the second largest cog, but it shifts both ways. Someone on a home mechanics page said they had the same issue with their hoods rolled back. They rolled them back into position and could shift down the cassette. It fixed that problem. Hopefully I'll have some time in the morning to work on the indexing and maybe I can take it out on Saturday for an off-road ride to work.
 

T4tomo

Guru
Someone on a home mechanics page said they had the same issue with their hoods rolled back.

That can be true, as depending on where the are rolled to can catch the lever or cable. Defo get the hoods back to position before indexing. It could also just be a simple limit screw position thing, but I'm sure you'll work it out.
 
OP
OP
rivers

rivers

How far can I go?
Location
Bristol
Update: IT'S ALIVE!!! Okay, that was a bit dramatic. The shifting us nearly perfect. Just a couple of tweaks to the barrel adjuster, and all should be good. Will be using it for my commute today, and should have some time for some fine tuning at work today.
Will do a full write-up at some point over the next few days.
 
OP
OP
rivers

rivers

How far can I go?
Location
Bristol
So, the mullet drivetrain. It's been a learning experience. I've never done much more than swapping out cassettes, chains, brake pads, and basic maintenance to my bikes before this- well with the exception of swapping a 50/34 chainset for a 46/30 on this same bike (including installing a new bottom bracket). So I was going into this blind, having only watched some youtube videos on various things like swapping out a derailleur and indexing. I couldn't find too much on the jtek shiftmate video-wise, but found a couple of in depth blogs that made installing it a bit easier.
Anyway, swapping out the derailleur was pretty easy, as was replacing the gear cable. I thought the gear cable might be a little fiddly, but the Orro has a cable outer throughout the bike, so it was a doddle to install. What was fiddly was actually installing the jtek. I cut the outer too short, mangled a gear cable, and all around spent far longer than I should have on it. A quick email to jtek informed me that due to the slick Orro cable routing, I would have to have a larger than desirable cable loop. So I just went with it.
The next issue I had was shifting down the cassette to the higher gears. It didn't want to move. Turns out, if the hoods are rolled back, it won't play nicely. So, once I was alerted to that possibly being my issue, it was quickly solved.
Setting the limit screws wasn't too bad, and it now shifts nicely up and down the cassette. It's a bit noisy, so I need to fine tune the indexing as well as shorten the chain a couple of links, but I'm happy overall. It was a learning experience, and I've probably voided any warranty I had on the bike, but I should be good to get up and over Dartmoor and Exmoor this summer. Now, I just need to source another 11-42 cassette for my road wheels on this bike, and it will be ready for wet weather and winter riding.

 

T4tomo

Guru
Excellent, glad you've got it sorted, and learnt a bit in the process. A marginally shorter chain should help crisp up the shifting too

Regarding the road wheel you don't necessarily need the expense of an 11-42 cassette, particular on road and not fully tour laded, a cheaper 11-32/34/36 will do the job, especially with a 30T inner chainring. The same chain will be fine to cope with both cassettes as both start at 11 and you know it fits up to 42.
 
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Dogtrousers

Kilometre nibbler
Indirectly you've answered a question that was hovering around in my mind which is - would there be any issue installing a 46/30 chainset in an R7000 setup? You did it so evidently not.

I'm sure there's plenty of life in my 50/34 yet, but when its day comes that's an option I've been considering. So one day, long into the future, I may dust off that idea.
 
OP
OP
rivers

rivers

How far can I go?
Location
Bristol
Indirectly you've answered a question that was hovering around in my mind which is - would there be any issue installing a 46/30 chainset in an R7000 setup? You did it so evidently not.

I'm sure there's plenty of life in my 50/34 yet, but when its day comes that's an option I've been considering. So one day, long into the future, I may dust off that idea.

Absolutely no issue installing the 46/30. I needed a new bottom bracket because the 46/30 has a 19mm spindle, not a 24mm. It took some doing getting the old BB out, but that was more, "This is my brand new bike, and I'm about to start whacking it with a mallet" than anything else.
 

Ajax Bay

Guru
Location
East Devon
Must have missed the well put together survey, that enabled that conclusion ["most people find a front triple a pain in the ar$e"] to be made.
Was pointed out by a kind chatty heart that these posts about triples and my request for the survey detail were wildly 'off topic'.
Joe is smoking one while he ponders.
 
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