Nexus on old Diamondback

After ten years I have had the chance to own my Diamond back I have decided for a change.
The Bike was well equipped by the STX components, beginning from the hubs to brakes continuing to any component you might thing of, except the frame indeed.  After the years every part deteriorates. Sprocket where changed for a cheep version, the deraileur changer has been replaced by the Deore type and so on and so on (the hubs stayed untouched and are grate up until now).

Through that time the bike served well except one thing. The changer (deraileur) has been always problem (don’t remember how it was with the STX version). The chain sometimes changed the sprocket by it selves, mostly when I need it the most on the cross.. kicking the bars with my knee. The chain rambled, hitting the frame all the time.

Everything changed on my trip to Tokio (the report plus dozens of photos) where I have experienced the super polished roads. The street was so narrow that you understand right a way why the the fixies takes the read the most. A was spellbound by their tire sound. Warm humming totally awesome. No noise nothing just the hum, peaceful and quiet.

A was kinda ready for  such a change. Right before I went to Tokyo I changed my tires for the Schwalbe Marathon a nice super smooth tires. Until then I had used the WTB mounting bike dirty cats grip tires. Which where good, but realizing that I ride the bike in the streets 98% of my all ride there was really no reason ride such tires. There were grate but slow and not cool enough. Up to that and thanks to my japan experience I have decided for the change.

The deraileur has to go off the bike and will be replaced by something peaceful and quiet, with less speeds. I use about 4 speeds, the rest just fills the gap in between.
After some surfing I found the winner. Relatively cheap hub with just enough speeds, passable quality and accurate gear ratio. The Nexus 8 speed hub.

Here we are. The hub came with almost all the necessary parts. Only the dirt caps where missing, both left and right. The are not absolutely necessary but are grate in long run. I’ve got one spare left dirt cup from my second Nexus hub I plan to use on the second bike so I used that one.

After the hub was build into the wheel the time of truth comes.
The first useful note. First I thought the Front Chainwheel has to have about 38 teeth and so I have looked for a crankset that will have such a wheel. Guess what I haven’t found one (that I like). After some attempts I decided use the actual 3 speed crankset and try what suites the most and keep it till I find the right set I would go for (the plan is to have single front wheel). As I said, based on my consideration I thought the second wheel (with 36 teeth) will be the one. As the tries shows , it might be the right one if you like to drive calm and will experience many hills or like the wood rides. If you’ll ride roads then the 42 teeth wheel is the right choice. The bike with the 42 wheel and Nexus runs unusually fast but the light gearing is not that light as I was used to.
To be more concrete, it all applies to a bike with 26″ wheels (rims). If you have 28″ wheels the 38 teeth crankset might be accurate.

There were couple problems I want to mention here. Just in the case you plan to do something similar to your bike.

Well it all depends on the frame you have. My frame is not meant for such a setup in “any” way. The frame has just enough room for the Axle not more, nada. The problem is that you actually need a room for the non-turn washers (see picture one, or check this video) and finally you need some space left to tense the chain enough. And That is the problem. In my case the chain was either short so the Axle won’t stay in the right place, or it was longer as you can see on the next picture.

I hoped the tension is enough but it wasn’t. The chain fall off. The worst. when the chain fall off it opens the plastic “safety switch” (cassette joint) so the shifter just falls apart. If this happen when you drive the hill or in the very street you are f…. up. So be aware this is something you have to keep in mind if you think of the Nexus. I would consider this part as one of the weekest part of the whole Nexus set.

So far so good. Knowing the chain can’t stay like that I went to find the chain tensioner. Because it is not common to use the inner hubs in this suburb there were no shops with tensioners least not around me when the chain fall. But luckily I found an incredible shop I did not known yet where they have dozen of such things. I bought Raptor SS. Which turn out to be the best choice anyway. It is good mainly because the common way how to mount tensioners is to let them tension the chain from outside inside, so the chain surrounds the maximum of the sprocket. But. In my case this is not possible. As you can see, the shifting part lays right where the tensioner would normally go. The raptor together with the frame mounting holes serves to my purpose just well. The chain has to be tensioned the other way, from inside out and the Raptor when mounted on my frame actually tensions the chain that way. There are also spring based tensioners, but I’m not sure if they are good. Some people say they are better, because you do not have to relocate the tensioner when it is wear out, but on the other hand they do not recommend spring tensioner when you have free-wheel. I think tht is mainly because if you pedal back fast the tensioner might stuck in some point the chain eases up and might fall off.

The result is not that elegant as I would like to be, but the chain stays where it supposed to stay and it wasn’t even expensive. Even more, now I can test any setup, any crankset I like and have the chain tensioned the way as it should be. Plus, the shifting nexus part does not suffer from the possible chain hits.

Don’t wary, there is a minus as well.

When you install the tensioner then you miss out the space for the right non-turn washer :/ I hope the left non…. will suffice. It has to.
And here it is, the second problematic part of the Nexus mounting is here. If your chainstay lenght is not accurate so the chain needs the chain tensioner you might not mount the Nexus properly. According the manual at least.

The bike rides well and I’m happy I did that change..will see if this setup will serve that well as the original STX counterpart.

If you have anything to say to this problem, any of your experience, anything that will improve my way of Nexus mounting, go ahead and write something.