genericbikedude

Project Bike Advice thread

So I need a rain/foul weather bike. I also need it to be relatively light, as I carry my bicycles up and down five flights of stairs. I may have access to a carbon fiber MTB frame for cheap. I'm thinking of giving it a nexus 8spd hub with drum brake, front drum/dynohub, rhynolites and fat tires, swayback bars and a big fat grandma saddle.

Preguntas:

Carbon fiber is weird. Carbon fiber mtb is even more weird. Fellow retrogrouches, do I need to be talked out of this?

Can internally geard hubs work with imperfect chain tension? I have vertical drops. I was thinking of half-linking it and finding a good cog/chainring combo.

Is the nexus 8 the only drum brake internal hub? Are there other better deals? (Besides rohloff )

The head tube is 1 1/4 inch. Yik. Do I have any options besides Aheadset and chris king?

Lastly, if I want to put 700C wheels on this 26" frame (YES, they will fit) in order to make them morfe transferable with my other bikes, what would be the practical effect on the riding characteristics of the bike, besides a higher BB?

Thanks all

HillRider

Carbon fiber MTB's should be pretty rugged in road bike service. If the frame is sound, I don't see why it wouldn't be suitable.

There are chain tensioners, rather like simplified rear derailleurs, that allow internal geared hubs (or fixed/single speed drives) to be used with vertical dropout frames. Otherwise you have to get lucky with a fortuitous chainring/ cog combination.

There are reducers to fit a 1-1/8" fork into a 1-1/4" headtube. Wheels Manufacturing makes them and Bike Tools Etc sells them for $15. The p/n is WB-HRED2

If you substitute 700C wheels will the brakes line up? Otherwise I don't think the handling characteristics will be much different. The slightly larger wheel radius will increase trail slightly and slow the handling a bit but this isn't intended as a crit bike anyway.

Keep in touch with how this project works out.

genericbikedude

Didn't know about the adaptor. Word, thanks.

The brakes will be inside the hubs--roller/drum brakes.

Sluggo

Sturmey-archer makes an 8-sped drum https://www.sturmey-archer.com/hubs_8spd_XRD8.php

I have a 7-speed nexus with roller brake (not really a drum), and I am not particularly thrilled with the brake performance. I am considering taking the brake off and going back to a rear caliper (already a caliper on the front).

Going to the taller tires will change your fork trail and change handling subtly. If it was really dialed in before, it will not feel quite right, but may not even be noticeable.

Retro Grouch 

Huh? Doesn't sound like a light bike to me.

MichaelW

Can you fit rack and fenders onto the carbon frame?
If you are using hub/disk brakes then rim wear is not a problem and you can safely go to a much lighter set of rims. Suggest you lighten up on your tyres too, maybe a 1.5" slick.
Sachs do a good hub gear system. Wheel removal is a bit easier with the oull-out click-box but it is a bit more vulnerable to damage. Many riders fit a small metal "derailleur protector".

caotropheus

gbdude
respostas:

First of all, the nexus 8 hub was a good option. If this is the first time you are using internal gear hubs, you will feel the amout of simplicity you're getting into to. And this is not bad, this is good, so good that I even build a road bicycle with a nexus 7. These gears never fail, do not get wet or dirty and are always greased. Within 150 years you can ask your great-great-grand children to service them. Take a look at Shedon Brown internal gear hubs and roller brakes. I would suggest ordinary V-brakes with wet wheather shoes or disc-brakes.

About the wheels I would suggest you keep the ordinary 26 inch wheels, toghether with a 38x559 tires. This would make the bicycle responsive, fast and safe for wet weather. Beside that, it will allow you riding in an urban area, you can jump side-walks and take advantage of other bumpy empty spaces.