Custom Cube Kathmandu build

[Deere John]

My current eBike build has served me well, to a limit. Now many problems have appeared, mostly frame-related. So this weekend I ordered a new frame. From 26" to 28" now. Actually with same hubs (both electric hub and rear Nexus-3). And the frame that I found was the Cube Kathmandu, with integrated carrier for increased stiffnes it looks like a good object for carrierbased eBike-build. There is a rail-system that addons a rail underneath the carrier for attaching bags or other things.

I was so thrilled when I saw this and that is also was on discount (125 Euro), so I ordered one. Will have it in a few days. Will not miss my old cheap cruiser-frame, it was kind of a pilot-project to see how this is, but I was really sold with the concept from the start. Now it's time to build something good to make the experience even better, it has actually become my most used, and most important (commuting) bike, so it's really time.

Here is the fully equipped bicycle, with suspension fork, XT-components and everything.
http://www.cube.eu/en/bikes/tour/kathmandu/cube-kathmandu-black-red-2015/
Really nice touring/trekking it looks like. Or as a daily commuter. It's actually these areas where I will use it. Maybe not for so long touring but the bike is good to have in case I change my mind later on. It's good with a add-on ebike kit, you can move it to another bike if you like

 

[Deere John]

...actually, that's a challenge now. I will build whole wheels from scratch with custom spokes and stuff. Except the hubs I have actually one more thing to carry over from the old bike, the brake and gear handle and new unused grips.

The rest of the things is ordered new, I thought it was best to do so instead of ripping my other nice 28" bike apart.

There is just one question, the fork. I couldn't find a fork that I felt was 100% right, I considered a damped fork (63mm travel) but changed my mind because I don't so much offroad so it's worth the extra weight. I ended up with a carbon fork. But is that a good idea on an eBike? I will have torque arm so I don't destroy the mounts. Can't see any other potential strains, but I could have missed something.

 

[Deere John]

The spec is (to be filled on later).

• Cube Kathmandu Frame.
• Radon Carbonfork w mechanical disc brake (Avid BB7).
• Nexus-3 rear hub w coaster brake.
• Wheels Mavic A719 w DT Champion 2.0 spokes.
• Tire Schwalbe Marathon 40-622.
• Electrics: 250W 36V front hub motor w 11Ah battery for carrier.

 

[Deere John]

Hmm, I think carbon fork is wrong for my bike, changed to Rock Shox Paragon. Will be better for my wrists.

 

[Deleted member 4366]

Don't waste your time with cable disc brakes. Get at least one hydraulic disc brake for the front. The performance of hydraulic brakes more than justifies their slightly higher price.

 

[trex]

I am not convinced that the current glued on Chinese hydraulic brake sensors are safe.
The magnet and sensor are not protected and depend on glue to keep them in place. I think for bikes with hydraulic brakes, the kit must be torque sensored like German bikes and do away with hydraulic brake sensors altogether.

 

[Deere John]

Thanks but I will give it a try, I have good components for it already. As long as it's better than my current v-brake I'm happy
On my MTB I have hydraulic they are really awesome.

Think also I will put my Nexus-8 from my other bike here instead. Another upgrade to the spec. It's always like this, you start low and the end result is more expensive. But it will be a great bike

 

[Deleted member 4366]

I think for bikes with hydraulic brakes, the kit must be torque sensored like German bikes and do away with hydraulic brake sensors altogether.

That's a strange thing to say. What's the type of pedal sensor go to to do with brake sensors?

In the worst case, you only need one brake switch - on the back brake. That allows you to have a hydraulic brake on the front without a switch.

 

[Deere John]

New spec, finally nailed it I hope!

• Cube Kathmandu Frame.
• Rock Shox Paragon fork 65mm w mechanical disc brake (Avid BB7).
• Nexus-8 (SG8-R22) rear hub w roller brake.
• Wheels Mavic A719 w DT Champion 2.0 spokes (back unspecified spokes 2.0)
  
• Tire Schwalbe Marathon 40-622.
• Electrics: 250W 36V front hub motor w 11Ah battery for carrier.

And today I got my first new piece, the Torq arm! building can start! will be most awesome, would need some days off... have included the full spec if anyone is interested.

 

[Deere John]

The order struggles, haven't dispatched yet since the spokes are delayed. So I cancelled the spokes. Ordered DT Alpine III spokes from another place instead, but DT Comp for the back wheel.

Also, I discovered that I had ordered rim brake rims! so bad, so I had to order new disc brake rims (TN 719), very frustrating!

• Cube Kathmandu Frame.
• Rock Shox Paragon fork 65mm w mechanical disc brake (Avid BB7).
• Nexus-8 (SG8-R22) rear hub w roller brake.
• Rims Mavic TN 719 w DT Alpine III spokes (back DT Comp)
• Tire Schwalbe Marathon 40-622.
• Electrics: 250W 36V front hub motor w 11Ah battery for carrier.

Today I got the fork, nice! Will be a great weekend this I feel the new motor controller is sent also so I think I got ALL parts next week!

 

[trex]

That's a strange thing to say. What's the type of pedal sensor go to to do with brake sensors?

In the worst case, you only need one brake switch - on the back brake. That allows you to have a hydraulic brake on the front without a switch.

the problem with mixing front hydraulic +rear cable operated is an esthetic one. The levers don't look like a pair. Perhaps someone should sell brake lever covers.

 

[Deere John]

the problem with mixing front hydraulic +rear cable operated is an esthetic one. The levers don't look like a pair. Perhaps someone should sell brake lever covers.

good point, would look strange I also have some levers with built-in switch for the eBrake, don't feel like replacing those.

 

[Deere John]

I also have some levers with built-in switch for the eBrake, don't feel like replacing those.

well, actually, today I noticed that the shifter I will change to. Nexus 8, has integrated brake handle!!

That will be a problem. On my current brake handle there is a second cable out, the brake-signal from a micro switch in the handle base. Can't use that now.

Any ideas?

I could maybe put some new switch or something there. Or I could purchase a single Nexus8-shifter without brake handle and still use my current brake handle, but that will not fit so good esthetically (actually the standard shifter takes good space so it's not really used for putting a separate brake handle beside it seems)

 

[trex]

you'll need a pair of 'inline brake sensors'

 

[Deere John]

I feel it's time for a recap here. This bike has now rolled over 10000km since I got it about two years ago. Since I also use other bikes I think I got a good mileage anyway. And it have served me very well! In the beginning there was some small issues, but that settled after a while and then it has just kept on serving me. I feel front hub drive for a commuter is very trouble-free. On my other ebike I have Bosch CX mid drive and that system is very hard on the drive train, this is the opposite, it actually relieves the drive train because it helps push on front wheel. Glad I didn't sell this bike which I thought of this summer. I even had an ad out and people called, but I regret myself and kept it. Close call! This bike will stay!

Reading above I see that I haven't written much here. But I rebuilt rear wheel in Nov 2015. From Nexus to a standard 10-speed XT which I got from my MTB, and new XT hub. Otherwise it's mostly the same, tried another steering bar for a while but didn't like it so I have now the same old again. Also saddle post changed to a regular with zero offset this time. Very great. The rear derailleur and cassette has been inherited from my MTB so they have rolled very long, maybe 15000 km. That is much for a cassette. So I will actually change cassette now anyway to a Sunrace 11-42 and also chainring to a fresh one.

Not too many problems. Controller is the biggest issue, I have fried three of them, one because I short-circuited it myself and two because they don't like riding offroad on high load with full assist. They overheat and die. But I have learned to handle that. Otherwise nothing serious, I crashed once and motor cable got damaged so I had to open up and fix it, greased the planets while I was at it. Sadenly the motor cover threads is bad now so I had to drill and put in some small screws myself. So next time something happens I think I need a new motor. Fork is serviced once only, but I would need to do it again now, it works but not as sensitive and nice as when new. My own built wheel has worked great, front wheel had to tune spokes once. Otherwise no mechanical failures at all.

This bike have changed my life actually. I now use car very very rarely. Actually my car didn't pass annual inspection this year so I thought of selling it and become a car-less person finally! But, I need a car sometimes right now when building house so that wont work. But I commute every day all year and go shopping, this bike can handle alot of weight. The integrated rack frame is very good! Sometimes I use two pannier bags, one big on each side, when I have many things to carry!

Once I had to bike a small adventure trip in Norway, 80 km on "Rallarvegen". Then this bike was actually the best suited then, but without assist of course. So I removed battery and controller and used it as a regular touring bike. Still with motor hub. That was a fantastic adventure. See photo below:



I also have some 10000km jubilee photos here from this week:






Now I will go charge my battery, cheers

 

[Deere John]

Upgraded the cassette yesterday. Tried it today. From 11-36T to 11-42T. Was a really tight fit. It's like 1mm spacing between this lever where the cable connects and the cassette, also 1mm between derailleur side and cassette when on gear #2. Also the B-screw had to be adjusted in the bottom and a little more to get clearance enough. I even had an occasion last ride today when it touched so I think I will need to find just a little longer screw so I can adjust 1mm more.

But now I have tried commuting today with this. Have had this on the shelf for a while wondering which bike I will fit this on, but it will be on this bike and the other bike will get the Sram EX1 upgrade instead. Have already XT M8000 11-42T 11s cassette on my MTB and that is most awesome on that bike I think (that's actually where these old XT-components inherited from). New chain also, it shifts very smooth and nice now with these new things. Before I used higher assist mode to get up the hills, now I can use higher gear instead! that will save battery and inspire to pedal with moderate assist.

 

[Deere John]

Like I wrote in the pic thread...

Today my motor died! Yesterday it started to sound bad, but today it got alot worse and now it's hardly spinning.

A front hub motor, think there is some problem with the one-way-bearing. If there are any there, or similar construction, anyone knows if there is a OWB in there on a standard china planetary geared drive?

Anyway, it has lasted actually just over 15000 km!!! Without any big problems, so I can not say I am more than happy with it anyway.
(15010 km to be exact, since april 2015)

 

[Trevormonty]

At least they are cheap to replace compared to factory middrives.
You also have choice of torque speed ratings for replacement.

 

[Deere John]

At least they are cheap to replace compared to factory middrives.
You also have choice of torque speed ratings for replacement.

yes, they are cheap, this one is amongst the cheapest I could find on Aliexpress

But now I am thinking about if I should replace it with a middrive (Tongsheng?) or a better hub motor like a Cute Q100, they come in a 260 RPM version which would suit good I think. Or maybe if I should get rid of the bike completely!? I use my new e-bike much now also but that is a MTB so not exactly the same use. Well, time will tell

 

[Deere John]

...but now when you said it. It would be interesting to go for a more proper RPM'd motor. My current ones maxes out at 42 km/h or so.

If I calculate, 722mm diameter, at this page:
https://www.easycalculation.com/unit-conversion/rpm-conversion.php

I get that it is 310 RPM now.

If I should go for the 260 RPM version it would get a top speed of 35 km/h. More suitable for me and would most probably have better torque for climbs.

Current one actually came from a pre-built 26" wheel where I took the motor and rebuilt for this bike with a 28" rim.

So... I think you gave me the answer there. I go for a different speced motor and would be even more happier. Because I think climbing torque is the only improvement area here.

So... now I only need to find the best hub motor and this time with a cable from side and a proper connector.