Downtube Mod

[iPAQsRock]

I'm looking to purchase a Downtube, have a couple questions.

Is it possible to replace the v brakes with disk brakes front and rear?

I like the 8FH, but was hoping for Orange. Did this bike come in more colors at one time, but all that is left know is White?

[iPAQsRock]

OK let’s try this angle on my question.

Is there a folding bike with 20" wheels or smaller that has disk brakes or is disk brake compatible?

[14R]

I know there are Birdys (or should I write Birdies?) with disk brake mods

http://www.long-john.com/diskbrkt.JPG


And Bromptons with disk brake mods:

http://www.foldsoc.co.uk/origami/20060204.jpg


Straight of the box with Disk brakes you can find Strida 5 and GoBike.

http://strida.yeahbike.com/images/strida5/strida_5.0.jpg


http://i.treehugger.com/files/th_images/gobikevertical.jpg



I hope that helps

[JosephLMonti]

OK let’s try this angle on my question.

Is there a folding bike with 20" wheels or smaller that has disk brakes or is disk brake compatible?

Apparently it is possible on a DT as well:

http://www.downtube.com/images/DowntubeBike/New_Bike_pics/P1010122.JPG

[Leisesturm]

Very nice information and interesting links and photo's but I have to wonder when innovation becomes overkill. I have had a DT IXFS for a year and cannot find any fault with the stock brakes. V-Brakes are such an amazing improvement, regardless of price, on any other kind of rim brake that going through the time and expense of upgrading to disks simply cannot make sense for the kind of riding the average commute folder sees day to day. If the OP had the wherewithal to consider a Brompton, Birdy or Strida I imagine he wouldn't be asking about the DT's upgrade potential. Probably s/he is not in possession of a TIG welder or prepared to pay a commercial fabricator for the work. For the rear the stock V-Brake is absolutely not worth messing with. For the front the o.p. will have to decide if it's worth a new fork with caliper mounts, a new disk compatible hub/rim and the disk brake unit itself. No doubt the replacement parts will all cost more than the entire DT.

H

[SesameCrunch]

Very nice information and interesting links and photo's but I have to wonder when innovation becomes overkill. I have had a DT IXFS for a year and cannot find any fault with the stock brakes. V-Brakes are such an amazing improvement, regardless of price, on any other kind of rim brake that going through the time and expense of upgrading to disks simply cannot make sense for the kind of riding the average commute folder sees day to day. If the OP had the wherewithal to consider a Brompton, Birdy or Strida I imagine he wouldn't be asking about the DT's upgrade potential. Probably s/he is not in possession of a TIG welder or prepared to pay a commercial fabricator for the work. For the rear the stock V-Brake is absolutely not worth messing with. For the front the o.p. will have to decide if it's worth a new fork with caliper mounts, a new disk compatible hub/rim and the disk brake unit itself. No doubt the replacement parts will all cost more than the entire DT.

H

+1! Well said.

[14R]

I did not see a clear desire from the original post on performance. Based on my personal experience, it is if not impossible, at least it is really hard to judge the circumstances that lead the OP to desire disk brakes (both front and rear). Maybe he/she will be riding under different scenarios that we are used to (like sandy areas where the rims will be destroyed after 200 miles using rim brakes, or something else one can come up with), or maybe he/she thinks that, no matter how much it costs or how not-so-efficient they are, disks brakes look just really cool and must be part of the package. It might be expensive beyond the cost of the bike. It might be an upgrade that really doesn't affect performance (it can even compromise it), but I believe none of these really matter for the OP (based on the information we have so far).

Just my US$0.02

[iPAQsRock]

14R, thanks for the pictures and info. I really like the gobike, too bad it seems to be unavailable :(

I seem to have been misunderstood by several of you. My question was what bikes were compatible, i.e. not requiring welding.

The question in regards to why I'd like to have disk brakes is mostly for the times I would be riding off road. I have a Roubaix road bike and was hoping on my next bike to have disk brakes. I would agree that disk brakes look good too. Being new to these types of bikes I’m just trying to see what is possible. I read the entire Downtube post, phew, and did not find any info on disk brakes, but then again I skimmed some of it ;)

[14R]

As some members here mentioned, if you are looking for effective brakes only, you are well served with the standard V-brakes featured on Downtubes. The hinge between the rear triangle and the main portion of the GoBike is known to be weak and not appropriate for off-road usage. I would go with a Downtube.

[jur]

AFAIK it is possible to buy a bracket that can be fitted to normal forks so that disc brakes can be mounted.

[tgzzzz]

I wasn't certain which bike the OP was concerned with "8FH", but the DT site lists:

"Front suspension transarch fork by Zoom with disc tabs".

This is what I have on my 8H. Doesn't that mean I could buy and add a disc setup without welding?

[Pine Cone]

I wasn't certain which bike the OP was concerned with "8FH", but the DT site lists:

"Front suspension transarch fork by Zoom with disc tabs".

This is what I have on my 8H. Doesn't that mean I could buy and add a disc setup without welding?

That's what it looks like on my two DT VIIIH's. They definitely have disc brake tabs. I was going to try one with a disc, but the stock brakes are pretty good so it never seemed worth the cost and trouble of building a new wheel.

[tgzzzz]

PC: not to hijack this thread but it may be over anyway: I followed your lead on grinding the teeth off of a 52T to serve as a chainguard. What did you use as spacers between guard and chainring? I tried washers but it didn't look right. Can I assume triple ring bolts are the right size? Thanks