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-   -   LBS says no Dyno Hub on Disk Brake bike - Is that right? (http://www.bikeforums.net/commuting/928577-lbs-says-no-dyno-hub-disk-brake-bike-right.html)

acidfast7 01-05-14 08:58 AM

Quote:

Originally Posted by Walter S (Post 16384095)
When you say "not hub dynamo" what is your point? You disagree that hub dynamos generate AC?

Edit: I misunderstood. You're saying hub dynamo is AC, bottle is DC I guess...

Not all bottle dynamos ... just the latest generation.

dscheidt 01-05-14 10:18 AM

Quote:

Originally Posted by Giant Doofus (Post 16382899)
Thanks! I didn't think that sounded right.

My problem now is that Memphis doesn't have a culture of transportation cycling, so I'm having trouble finding an LBS that can answer basic questions like this. Even if I figure out on my own which wheel/hub to order, I'm going to have a heck of a time finding a shop I trust to install it.

There's nothing terribly exotic in a bike that's used for transportation, versus one that's used for anything else. So, if you can find a shop that's good with bikes, and who are interested in the project (or at least, indifferent and not actively hostile), you can tell them what you want, and they'll manage it. Installing a wheel with a disc brake and a generator is no different than installing a wheel with just disc brakes, except there's a wire that plugs in. Other things, like racks and fenders, are easy enough for someone with some mechanical ability to install, even if they've never done it before.

You might have to do some research or ask questions here, to know what you want or what's possible, but that's not surprising. There are just too many products for everyone to keep track of, and you're not the mainstream customer.

The other alternative is to do work for yourself. That might not be a bad idea, anyway, at least enough for basic work.

fietsbob 01-05-14 11:39 AM

Semantics OCD aside, I have 2 SON, 1_centerlock, [20"] and 1_6 bolt [26/700c].

work just fine, .. have for years.

centerlock on the pack-for-travel Bike Friday is perfect, take off the disc,
and pack separate from the wheel so it stays flat, when you remove the wheel.

Giant Doofus 01-05-14 11:57 AM

Quote:

Originally Posted by tcs (Post 16383258)
To get away from rim brakes, you could even go with a Sturmey-Archer X-FDD Dynohub with its drum brake or a Shimano dynamo hub with a roller brake.

I'm considering this for some other bikes I've looked at. This particular one happened to have the right fittings on the front fork for a disk brake. It looks like a bike that can do most of what I want, so I asked about adding a dynamo and that's where the confusion started.

Giant Doofus 01-05-14 12:02 PM

Quote:

Originally Posted by hueyhoolihan (Post 16383528)
psst!.... i think the post might have a generator and an alternator mixed up. along with the difference between a producer of energy and something that changes its form. in this case from kinetic energy to electrical energy. it's called a transducer, i think. but 'nuf said.

it's really not important on a bike forum, is it? really.:)

Confession: I had no idea that there even was a difference between a generator and a dynamo hub until I read some of the responses on this thread. It's possible the LBS guy was confused by my terminology, but I don't that was the main problem. What I said was, "I like this bike a lot. Can I put a dynamo hub on it to power my lights?" He should have been able to figure out from context what I meant. I think what he wanted was to sell me the USB lights he had in stock. :(

Giant Doofus 01-05-14 12:05 PM

Quote:

Originally Posted by dscheidt (Post 16384366)
There's nothing terribly exotic in a bike that's used for transportation, versus one that's used for anything else. So, if you can find a shop that's good with bikes, and who are interested in the project (or at least, indifferent and not actively hostile), you can tell them what you want, and they'll manage it. Installing a wheel with a disc brake and a generator is no different than installing a wheel with just disc brakes, except there's a wire that plugs in. Other things, like racks and fenders, are easy enough for someone with some mechanical ability to install, even if they've never done it before.

You might have to do some research or ask questions here, to know what you want or what's possible, but that's not surprising. There are just too many products for everyone to keep track of, and you're not the mainstream customer.

The other alternative is to do work for yourself. That might not be a bad idea, anyway, at least enough for basic work.

Good point. I may be approaching this the wrong way. It may be that finding the bike I want and finding the shop I want to work with will be two separate projects. There aren't a lot of step-through steel options where I live. I like the shop that does tune-ups on my current bike, but they only sell road bikes. I'm guessing they wouldn't mind taking on the project of making modifications to a bike I bought elsewhere. I'll go in and talk to them about it soon.

unterhausen 01-05-14 12:46 PM

I go to a great shop, and they know next to nothing about dynos. Most bike riders don't do much night riding and when they do they use battery lights. As misguided as that may seem, it's the way things work. I tried to talk them into tracking down the source of the low-cost dyno wheels that were around a few years ago, but they didn't think there was a market

fietsbob 01-05-14 02:09 PM

even if they dont think ordering wheels ahead of time, to have on spec,
surely the distributors catalogs will have them available.

Ex: handspun is the wheelbuilding division of QBP, so have them ask ..

any QBP parts combination, I suspect.



FWIW, My step through bike is a Bike Friday..

Wanderer 01-05-14 02:20 PM

It appears that some great deals can be had from Taylor Wheels......................

dscheidt 01-05-14 04:02 PM

Quote:

Originally Posted by Giant Doofus (Post 16384630)
Good point. I may be approaching this the wrong way. It may be that finding the bike I want and finding the shop I want to work with will be two separate projects. There aren't a lot of step-through steel options where I live. I like the shop that does tune-ups on my current bike, but they only sell road bikes. I'm guessing they wouldn't mind taking on the project of making modifications to a bike I bought elsewhere. I'll go in and talk to them about it soon.

Your bike shop likely has access to a lot more bikes than you think. Talk to them.

cyccommute 01-06-14 07:30 AM

Quote:

Originally Posted by Giant Doofus (Post 16382829)
I'm starting to zero in on a new commuter I think might work for me. It's the KHS Green 8 step-through frame. Here's a link to the specs: http://khsbicycles.com/bikes/2014-kh...ls/green-8-14/.

I'm trying to get away from rim brakes, and the guy at the LBS says that this bike can be equipped with a disk brake on front. Problem is, I also want dyno hub lighting. The guy at the shop says that there's no way to use a generator hub on a wheel with a disk brake. That doesn't sound right to me, but I don't know a lot about brakes or dyno hubs. So, all-knowing forum members, help me out here. Is that right, or is this guy confused?

I'd like to point out that the bike you linked to doesn't have tabs for disc brakes. Perhaps the bicycle's specifications have been changed but that particular bike can't be fitted with discs without a fork change.

Giant Doofus 01-06-14 07:51 AM

Quote:

Originally Posted by cyccommute (Post 16386514)
I'd like to point out that the bike you linked to doesn't have tabs for disc brakes. Perhaps the bicycle's specifications have been changed but that particular bike can't be fitted with discs without a fork change.

There are two things about the specs that made me think it would. Under "fork" it says "full CroMO unicrown, low rider and fender bosses with Disc" and under "hub" it says "FT: Alloy QR, Disc ready." The LBS guy said that meant the front wheel could take a disk brake, but he could be wrong. What does that mean?

Giant Doofus 01-06-14 07:52 AM

Quote:

Originally Posted by acidfast7 (Post 16383898)
full wheel

700c

front wheel dynamo (Alfine DH-S501)

disc brakes (also works with rim brakes)

88 for the machine built and hand-trued front wheel

20 for shipping and customs to the US from Germany

108 total which is roughly $130 (not sure how much you're getting charged but this is a very nice off the shelf solution from a very reputable site)

http://www.bike24.de/1.php?content=8...;product=62193

I missed this post earlier. Thank you. That does look like a good source.

acidfast7 01-06-14 07:55 AM

Quote:

Originally Posted by Giant Doofus (Post 16386563)
I missed this post earlier. Thank you. That does look like a good source.

No problem.

That wheel is nice because you can run it with rim brakes OR disc brakes ... use it now with rim brakes and then save it when you upgrade to a disc-compatible fork.

Personally, I think it's excellent value and you'd fetch almost $100 on the used market in the US if you want to discard it.

Giant Doofus 01-06-14 08:43 AM

Quote:

Originally Posted by acidfast7 (Post 16386573)
No problem.

That wheel is nice because you can run it with rim brakes OR disc brakes ... use it now with rim brakes and then save it when you upgrade to a disc-compatible fork.

Personally, I think it's excellent value and you'd fetch almost $100 on the used market in the US if you want to discard it.

I agree - it looks like a really good value. I may just go ahead and order it now for my current bike. I could always move it to a new bike down the line. Thanks, again, for the passing this along. I'm also going to bookmark that site. Lots of good stuff there.

acidfast7 01-06-14 08:52 AM

Quote:

Originally Posted by Giant Doofus (Post 16386682)
I agree - it looks like a really good value. I may just go ahead and order it now for my current bike. I could always move it to a new bike down the line. Thanks, again, for the passing this along. I'm also going to bookmark that site. Lots of good stuff there.

Have fun!

cyccommute 01-06-14 09:43 AM

Quote:

Originally Posted by Giant Doofus (Post 16386557)
There are two things about the specs that made me think it would. Under "fork" it says "full CroMO unicrown, low rider and fender bosses with Disc" and under "hub" it says "FT: Alloy QR, Disc ready." The LBS guy said that meant the front wheel could take a disk brake, but he could be wrong. What does that mean?

Specifications change on bicycles but the bike pictured in your link doesn't have the tabs on the left side of the fork for disc brakes. The tabs are very prominent like in this picture of a rigid fork that is disc compatible

http://i144.photobucket.com/albums/r...right-fork.jpg

Compare the tabs to this fork that isn't disc compatible

http://i144.photobucket.com/albums/r...e/IMG_0335.jpg

Although taken from a different angle, you can see the tabs in the first picture and you can see that they are missing in the second. Even when taken from the drive side, the disc tabs are very prominent

http://i144.photobucket.com/albums/r...e/IMG_0168.jpg

You may be looking at the KHS Green DLX or KHS may have changed their specification for the fork to one like the Green DLX but the picture of the linked bike doesn't have disc tabs.

Giant Doofus 01-06-14 09:51 AM

Quote:

Originally Posted by cyccommute (Post 16386844)
Specifications change on bicycles but the bike pictured in your link doesn't have the tabs on the left side of the fork for disc brakes. The tabs are very prominent like in this picture of a rigid fork that is disc compatible

http://i144.photobucket.com/albums/r...right-fork.jpg

Compare the tabs to this fork that isn't disc compatible

http://i144.photobucket.com/albums/r...e/IMG_0335.jpg

Although taken from a different angle, you can see the tabs in the first picture and you can see that they are missing in the second. Even when taken from the drive side, the disc tabs are very prominent

http://i144.photobucket.com/albums/r...e/IMG_0168.jpg

You may be looking at the KHS Green DLX or KHS may have changed their specification for the fork to one like the Green DLX but the picture of the linked bike doesn't have disc tabs.

Your pictures are incredibly helpful. I've never been able to figure out how to look at a fork and tell if I'm seeing disc tabs. Now I can see clearly what to look for. I'm not sure if the specs or the picture for the KHS are right. I'll have to look at the bike itself. Thank you!

fietsbob 01-06-14 10:22 AM

You can buy a disc dynamo hub and use it w/o the disc, until you replace the fork .

+ S-A drum brakes and the hub generator- combo can replace rim brakes, without changing the fork.

acidfast7 01-06-14 10:25 AM

Quote:

Originally Posted by fietsbob (Post 16386949)
You can buy a disc dynamo hub and use it w/o the disc, until you replace the fork .

+ S-A drum brakes and the hub generator- combo can replace rim brakes, without changing the fork.

I'm assuming the OP wants a prefabbed wheel ... so in your case the wheel would have to have brake tracks and disc compatibility.

(That's why I like the one I posted!)

cyccommute 01-06-14 11:00 AM

Quote:

Originally Posted by Giant Doofus (Post 16386876)
Your pictures are incredibly helpful. I've never been able to figure out how to look at a fork and tell if I'm seeing disc tabs. Now I can see clearly what to look for. I'm not sure if the specs or the picture for the KHS are right. I'll have to look at the bike itself. Thank you!

One note on the Salsa: You see 3 holes on the fork leg. The two upper ones that stick out from the fork the furthest are the disc tabs. The lowest hole that is closest to the fork tip is the fender mount. You should see a similar configuration on the KHS.

slcbob 01-06-14 12:41 PM

OP, I'm still not certain whether you're getting a dynamo, magneto, generator, or alternator. But it does look like you'll be getting some disc brakes. There are some hub brakes as tcs mentioned but I've not been impressed in two test rides and a bit of eavesdropping.

I suggest a single BB7 front mechanical disc. If you get the right one for the throw of your brake levers (I believe you want the BB7 Road model) then you don't need to change anything else, just the front wheel and maybe a new brake cable.

Forget about the back brake. The rim brakes are enough there, even in the wet. That will save you 50%+ on the cost (rear wheel and the second disc) and net you 99% of the stopping performance.

Giant Doofus 01-06-14 12:49 PM

Quote:

Originally Posted by slcbob (Post 16387406)
OP, I'm still not certain whether you're getting a dynamo, magneto, generator, or alternator. But it does look like you'll be getting some disc brakes. There are some hub brakes as tcs mentioned but I've not been impressed in two test rides and a bit of eavesdropping.

Probably because I'm not clear about the differences ;) I just want a hub that makes my lights go! The one I'm planning to buy is the one acidfast7 recommended. It is described on the site as a dyno hub (Shimano Alfine DH-S501).

Quote:

Originally Posted by slcbob (Post 16387406)
I suggest a single BB7 front mechanical disc. If you get the right one for the throw of your brake levers (I believe you want the BB7 Road model) then you don't need to change anything else, just the front wheel and maybe a new brake cable.

Forget about the back brake. The rim brakes are enough there, even in the wet. That will save you 50%+ on the cost (rear wheel and the second disc) and net you 99% of the stopping performance.

That's helpful. I don't think the bike I was looking at would even take a disc on the back. I've been reading Sheldon Brown's pages on brakes, which make it pretty clear that the front brake is the most important. I figured I could always put a roller on back (bike has a Nexus 8 hub) if needed.

noglider 01-06-14 02:53 PM

You could get a front wheel with a dynamo and a drum brake in the front hub. It would weigh more than a disk brake, but it would offer the same advantages. Drum brakes don't care about the weather.

tcs 01-06-14 03:22 PM

Quote:

Originally Posted by noglider (Post 16387822)
You could get a front wheel with a dynamo and a drum brake in the front hub. It would weigh more than a disk brake, but it would...

...be less expensive and need less maintenance. No quick release, though.


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