Installing and rerouting brake/shifter housing

Ok so I tore this bike apart and rebuilt it into an e-bike. I knew very little of bike maintenance before doing this.

I upgraded to Shimano V-brakes from the previous middle pull cantilever brakes and I have Jagwire brake and shift cable housing. So first of all, the previously the brakes and shifter cables housing didn't run continuously - exposing the bare wire between the cable stops. So first of all, I'm assuming I should run the brakes the same way is before, or is there any advantage for running continuous housing?

Secondly, the bottom bracket was replaced by the mid-drive electric motor. The shifter cable previously was run underneath this. There is now no space underneath to route this cable housing. So now is it possible for the bike tho shift normally if I run a continuous shifter housing all the way to my rear derailleur? If not, how would you approach this? Also, should I put a lubricant in the housing?

As a reference, this is a Trek Multi-track 730.

Should the shift cable housing just run parallel to the chainstay and just run it along the downtube?

It shouldn't affect the shifting much running continuous housing.

Usually lube isn't needed when cables are new, some lube will actually expand the inner plastic liner and make the cable bind.

When you wrote you have brake and shifter housing, that's two different kinds, and they don't interchange well?
Also, it takes special cutters to get a clean end on the shifter housing.

Voltron said:

Also, it takes special cutters to get a clean end on the shifter housing.

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If you don't have cable cutters, a dremel will work. I use the Felco C7 cable cutters. The cable stops on the downtube are used to save weight on a bicycle. Some cyclists spend a lot of money for the lightest bicycles and components. On heavy frames where it doesn't matter, it is probably done for cosmetic reasons. Of course hydraulic brakes require continuous hoses to the calipers, so newer frames will not have the cable stops and will have braze-ons for zip tying the hoses to the frame. If you don't mind making the bike a few grams heavier, you can run continuous cable housing without any detriment.

As long as the shifter housing is compressionless, (not the cheap spiral-wound stuff), or it's pretensioned well enough to take this out of the picture (if it's possible without affecting shifting) and the ends are clean cut and level, and the endcaps are installed correctly and everything is fully seated when you begin setting up the tension on the shifters, it should work fine.

I've found I like Jagwire stuff, and they make kits for doing a typical bike. You can probably get better prices than these, but this is one example:
https://www.amazon.com/dp/B077F9ZMKF
They make specific stuff for specific types of shifters that might be more applicable to yours, so check them out to be sure you get the best-fit option if you go this route.

I've used a lot of cheap / generic stuff over the years due to lack of budget to get better stuff...the Jagwire is like an order of magnitude or more better performing than anything else I've ever used, including stuff that was already installed on bikes I've gotten (always used, though some in like-new condition, and some of them pretty nice bikes to me).


I've never had the (expensive) cable cutting tools, like this one
https://www.amazon.com/dp/B000OZBINY
but have used an actual Dremel-brand variable-speed tool (that I've had for decades) along with actual dremel-brand cutoff wheels to successfully cleanly cut shifter and brake cable. Making sure you don't heat the cable during the cutting such that the liner or exterior deforms or melts is important. Might take some practice on old cables to get this just right to not melt anything and to also cleanly cut the metal without leaving burrs.

RunForTheHills said:

The cable stops on the downtube are used to save weight on a bicycle.

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It's also done to reduce cable friction. Less housing means less friction...but it only works in places where you can have a straight run between housing ends; a lot of "modern" frames have curves that prevent being able to do this, and end up with full-housing for the whole bike. Normally it's not an issue, but with cheap cables and cheap shifters you can end up with problems with accurate shifting, especially as things wear. Brake cables have less of an issue with this, sometimes you end up with brakes that rub because the cable friction prevents fully releasing the caliper after braking, but that's the only effect I've personally had from that particular issue.

I've had plenty of problems with non-compressionless housing on brakes causing me to be unable to adjust brakes to not rub and still be able to fully apply them, though, especially for the long cable runs I end up with on my cargo bikes/trikes. So I don't like using that stuff.

Thanks all for the input! I borrowed a bike tool kit and stand from my tool library so I had no issue with cutting cables. Just to clarify I do have separate brake and shift housing.

I feel exhausted and like I hardly even got anywhere but I guess there was progress made today. I got the front brake to install just fine to start. Next, I tried the rear brake. Since I upgraded to a V brake, I guess I'm altering the way the bike was made to function with the cable stops. I used the stops with the bare wire exposed in the middle and it seems like there's a little too much slack there. I can get the brake wire taut when I first install it, then when I initiate the brake the exposed brake cable on the cross bar looks pretty loose. Additionally, the rear tire needs to be trued for this to work properly.

Next I tried to eyeball and cut the housing for the shifter. I connected a continuous tube of housing and connecting it to the rear derailleur. I tried a few times to shift and I got nowhere, the chain wasn't moving at all. I guess I just don't how this works. Maybe I need to do a little more research.

Lastly, just for good measure, I just connected the battery to the Tongsheng TSDZ2 controller. I connected the thumb throttle and to my surprise, it worked! The rear tire was spinning! I was so happy that I got this to work. I couldn't get the pedal assist to work but I assume I have to connect the magnet and the sensor on the rear wheel for this to activate.

So there were some ups and downs today. I guess I learned a little but still have a little ways to go. Still have to figure out how to clean up the messy cables as well. *exhausted*

If it has torque sensing, they can be hard to trigger on a repair stand as the back wheel moves too easily to get much torque at the crank, unless you hold the brake against the wheel by hand, but watch out for spoke fingers.

With the shifting, is the cable installed in the shifter right?

And the final gear that the chain is on in the picture is the high gear, are you starting out with the shifter on the highest number too?

Voltron said:

If it has torque sensing, they can be hard to trigger on a repair stand as the back wheel moves too easily to get much torque at the crank, unless you hold the brake against the wheel by hand, but watch out for spoke fingers.

With the shifting, is the cable installed in the shifter right?

And the final gear that the chain is on in the picture is the high gear, are you starting out with the shifter on the highest number too?

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I was able to get the shifting working. There was too much friction with the continuous housing. I cut it into two sections again and used the stops and now it works decent. I think I just need to get the spacing right.

I don't know what I'm doing wrong but I can't seem to get the torque sensing to work. I just hooked up the magnet and the speed sensor. Do I have everything plugged in correctly? I have a bunch of extra cables and I'm not sure what they're for. Are these necessary?

Oops, I guess the magnet wasn't close enough to the sensor.

Still gotta figure out the brakes but I'm getting there.

Are the V brake arms pretty parallel to each other or kinda splayed out?