NewEnglandCycle

Hi guys and gals.

I have a Speed-Uno that I would like to upgrade to a two gear bike. The bike gets dirty from salt/snow as well as sand and rain. Which hub (includes a coaster brake) would be more reliable? I read all the threads on adjusting the spring tension to achieve the proper gear change speed.
Which front sprocket would compliment the change as I will use the bikes on hills 25% of the time? (46T Kinetix?)

The purchase of a hub is a definite, the following are ideas that were pondered.

I would also like to add a front brake, but don't know where I can buy all the parts to make it work well.

Lastly, I contemplated upgrading to 451 wheels with road tires. Will the bike be quicker due to the lesser rolling resistance? I understand that the front brake will need to be changed or adjusted.


Thanks for all the good reading material.

dynaryder

From what I've read,none of the two speed hubs are sealed well enough for what you're talking about.

https://mccraw.co.uk/sram-automatix-review/
"Again like the S2C, the SRAM Automatix doesn’t have seals over the bearings, so it’s likely to need a lot more attention through winter than your average hub."

If you're going to be riding in harsh conditions,you may want to look at a three speed hub.

There are numerous front caliper brakes that will bolt straight on. Dahon used to include one with the Mu Uno. Any folder shop can hook you up with one,or you can just do a bit of Googling.

451's aren't going to make you any faster,they're just going to limit your tire options. You can get 1" tires and low spoke count rims in both 451 and 406 sizes.

pacificcyclist

SRAM A2 is more reliable than the Sturmey Archer S2C based on most usage. I am on my second S2C on my Speed Duo (Uno) which I like it a lot. If your main ride is through salt and snow, I would best recommend the Shimano Nexus 3 hub as it is better sealed than either the two. The shop here strongly recommended the Nexus 3 for commuting as they service a lot of Duos (be it on SRAM A2 and S2C) and they don't cut it. It rains a lot here and snows, so unless you are willing to shell out money every month just to clean it and relube, I go with the Nexus 3. Btw, I killed my S2C due to this. The double speed hubs don't have much seals cause seals cause MORE DRAG as if there are already a bit anyhow. The Nexus 3 is cheap and reliable. Should last you a few thousand miles before due maintenance.

The problem with coaster brake bikes is that, there is an inherent DRAG from the hub itself; more so with the rather poor stock hub that came with your Uno -- that thing just drags! So in order to get the Uno to go faster, reduce the drag from the coaster brake by getting the shop to adjust it if they know how. 451 wheels only add to cruising speed, BUT because the wheels are bigger, they accelerate less than the 406, which means your gearing will become slightly higher. You can do the faux 451 deal by going with the Big Apples, because they are slightly larger in circumference compared to the stock tires and they do roll better. Not the best in class in terms of rolling resistance, but I managed to keep up with the Trek Madones and Cervelos on fast club rides with my Mu SL which gives me a pretty darn good workout anyhow.

In regards to gearing with the SRAM A2 and spring tension and shift point. This is based on rider preference and riding style and it's not exactly perfect science either. The A2 is good for reliable flat with some hills thrown in, but if you need to do extended climbs, I would just go with the Nexus 3 hub. It has low, medium and high gearing and you manual choose which gear you want to be in. No automatic, no limitations how much pedal spins you need to turn because you don't want to excite the A2 into shifting to a higher gear that you do not want. The Nexus 3 hub is cheap and reliable.

Adding a front brake to the Uno isn't difficult. Most BMX style front caliper brakes will work with it. Tektro is a good brand. I use a Diacompe cause I'm a bit old school.

NewEnglandCycle

Thanks for all the help. Im new to customizing bikes. Rode some folders today and cant wait to modify mine.

For the hub, I will go with the A2 so that it drops back into the lower gear when I come to a stop. I read that the kickback changes gears on bumps, so having the hub default to 1:1 will alleviate the issue of being in the wrong gear.

As for the details, can someone point me in the right direction to choosing a rim that will fit the stock tire?

Also, I would like to fit the brakes, cable and lever myself. Can I be pointed as what parts to purchase?

Thanks in advance!

jerrysimon

More info in the link lower down on the forum

I have used an A2 on my Brompton all through the winter without any problems. I did add a lot of grease when I had it stripped down to adjust the change point though.

Jerry

NewEnglandCycle

The A2 most likely will be the hub of choise. However, does the Nexus 3 come in a coaster brake configuration?

Thanks.

jerrysimon

The SRAM T3 does as I have a 28H version one with a coaster. Also fits 120mm rear frame spacing.

This Nexus seems to though I am not sure what the OLD is given the Uno rear dropout spacing in narrow.

https://www.ebay.co.uk/itm/shimano-in...item53ef53447a

Jerry

NewEnglandCycle

The a2 is a go due to the lack of cables. Ordering just a rear wheel and will try to mach it as best as possible to the front so as the bike wont look customized.

Can someone please advise which brake too look into (size and style)?
Also, anyone with a folder have straps on thei pedals?


Will post some pics when I finally put it all together.

dynaryder

Yes. OLD is 120mm.

pacificcyclist

Do you have a local shop that deals with BMX bikes? They will be able to help you install one in a flash plus tune it so it stops well. A BMX shop will show you all kinds of long caliper brakes you like, even the pricier fancy ones with the nice gold trims if you want that kind of look.

In regards to pedals. I use clipless pedals, but you can always go with Power Grip pedals. It helps on the hills mainly by allowing you to pull up the pedals since you only got 2 speeds. Just be careful when you attack a hill that you should anticipate the gear shift and don't loose balance while standing on the pedals.

Good luck.

And yes, the Nexus 3 comes with a 120 OLD spacing. It's a popular upgrade option for single speed folders seemingly because it is reliable and works well in hilly areas (which is where I live) and it involves just a single shifter cable which does not interfere with folding.

NewEnglandCycle

There are bmx shops locally but being where I live, most are rip offs. I have the ability to install and modify anything, so I was hoping to piece it together myself and install it. As for the nexus 3, it looks great but in the end, there is still a part protruding which may break off. For now the Automatix 2 will do the work. I may make a wheel with a nexus 3 and install the shifter on the rear frame so no cables have to be ran, but first need to read more how to set up the cables.

pacificcyclist

Thankfully, I live in a town where the local BMX shop isn't a rip-off joint. But again, there are good brakes and there are bad brakes and you always get what you pay for. Be wary of caliper brakes that are cheap, but flex a lot during braking. This is something you want to avoid getting installed on your Uno. Installing a front brake on the Uno isn't difficult at all. I paid about $24 Canadian to have it installed onto my Uno that includes all parts, labour and taxes inclusive.

The SRAM A2 is a good hub as long as you are happy with the lower gear setup, because getting a low gear on the A2 means compromising the middle gear, which means that it can be too low for you causing some frustration but if you don't have a low enough gear to climb hills, then you too will be a bit disappointed. My suggestion to you is what I did. Go to a local shop that carries the Tern Duo and ride it. If you like it, then you will like the A2. If you don't, then you won't. As I said earlier, the Nexus 3 is a popular choice because it does offer a real low gear ratio without needing to compromise the middle and high gearing. Most people find this very useful because they prefer function over style. I happen to be happy with my S2C, finding a compromise for the 2 gears and worked out well, but I would have gone with the Nexus 3 because now I knew the S2C can not be depended upon for the nasty winter and heavy deluge rain I commute in during the West Coast winter seasons. If I live in a relatively flat with minimal rolling hills, the A2 would be perfect. But then, I don't.

Good luck on your upgrade!

Dahon.Steve

Interesting.

A coaster Brake does have drag as you state but some hubs have more drag than others. For example, my Shimano 7 with roller brake had loads of drag causing me to sell it! On the other hand, my Shimano Nexus 3 with coaster brake has much less drag overall. My Sturmey Archer 5 speed hub with rear roller brake has very little drag but you have to know how to set the wheel or you'll get loads of drag!! LOL! Now when I think about, maybe my Shimano 7 wasn't set up correctly!

I have two bikes with the Nexus 3 and can't speak more highly of it. It's hard to say if it's better than Sturmey Archer 3 speed but they are so close. I like the low gear but I often wish it was lower. However, what I really wish is that there was a fourth gear that is one step lower in particular for head winds or near the end of a ride when your legs are tired.

What's real important in doing a correct setup with any hub is finding a gear that your comfortable riding in 95% of the time. The OP didn't state what gear that is but it's critical to get the right chainring/cog combination or the bike will be either too high or low geared. I like a bike that's has a 54' inch 2nd gear when constructing a 3 speed bike. A lot of people would choose a higher gear but you have to get this right.

NewEnglandCycle

Hey there guys and gals.

Added the front brake, and what a difference it makes!

Would like to change to a two speed hub. Took a look around and found this video. https://www.youtube.com/watch?v=DFsjIc6DUDc

Is that a Sram Automatix?

I am still trying to see if I can do this on a budget and keep the stock wheel but understand the 28h hub isnt available. If I do need to buy a wheel, what am I looking for at a reasonably similar quality and size to oem so I can keep the stock rubber on.

Lastly can I mount "high pressure" tires on the original wheels?

ThorUSA

I happen to have one rear wheel in black left. But I highly discourage to change the shiftpoint. Sure for the folks who have experience in ighs , the ones who have a second one laying around and are not afraid to render the first one worthless, the peeps with more money to burn, just to be different than the rest ( I actually like these ..lol ) and and and ...
A folder should be ridden sitting down and spinning rather than mashing standing up... if you change the gearing than that cadence will most likely drop, which is counterproductive.
contact me with details.... Its a nice swap for sure...
High pressure tires ... what you mean with high pressure ... ? If you look up Schwalbe tires, i have all max pressures listed, and they all fit on standard rims ... the Ultremo has 160 lbs ... ( although I would stop at 140, plus most pumps will have difficulties anyhow ) and they will work on Tern or Dahon rims and many others...
somewhere I do have Mu uno brakes listed as well.... but again contact me and I help you find the fitting stuff.. I do like to have a front brake also, I am torn between good simple looks and safety on this one though ..lol

looks in the Vid to be a Sram A hub...
also the guy in the vid makes a mistake. you start with the seatpost down.... than if folded the bike rests on the seatpost instead of the expensive chainwheel he added to the bike .... :-)
Just sayin

Best Thor

NewEnglandCycle

Another option to ponder with, Sram iMotion3. 130mm.
Any thoughts guys?

pacificcyclist

When I first got the S2C Sturmey Archer, it has some significant drag to the hub. Perhaps it was dying because it didn't last very long until the whole mechanism inside disintegrated. The whole hub locked up.

The new internals that is now in it is much smoother and has significantly less drag than the original hub. The SA mechanic at the bike shop did a superb job of fixing it and tuning it up so it now pedals a bit easier than before. Still compared to a NON-IGH bike, an IGH bike always has some drag. Which is why my friends who own the Speed TR or the MU XL envy my Dahon Mu SL setup. It's fast and it's easy to pedal with no drag and that's what I prefer it over IGH and ofcourse the bloody weight I have to carry up the hill with an IGH is a no no for my Mu SL.

pacificcyclist

You're not really sure what you are trying to accomplish here are you?

It's hard to give you some thoughts if we don't know what you really want.

Basically, a 1, 2 or 3 speed bike is a compromise of gearing. So for this purpose, you've got to know what you want the bike to do for you. When you get into the 5 speed IGH however, then there's a little compromising, because with 5 speeds, you have your lower and higher gear and you will be more seated while riding your bike.

Like Thor, I strongly suggest not to change the shift point of the A2 and just ride the Tern Verge Duo and see if you like it. With 2 or 3 speeds, you're not going to get a lot of options. If you want a fast bike, you need big gears, but when it comes to climbing a hill, you will be forced to stand and pedal which puts a lot of stress on the frame and the steering post. You're not going to fit a 130mm or any big hub either. If you already thinking of those bigger IGH hub, why don't you just sell the Speed Uno and get an Eco 6 or similar bike?

I got the Speed Uno converted to Duo because I didn't want to mess with the cables (except front brake) when folded and I roll the bike into trains and seabuses which I can't with my Mu SL. These benefits alone serve me well on transit commute with trains and ferries and the 2 gears serve me perfectly to go between station and places I want to go. It's hideous ugly look is a theft deterrent against a plethora of nicer Surlies, Somas, Salsas and those fashionista Cervelos or Madones that are parked outside on shops. I carry a super light lock as a result, which means I'm not carrying a 5 to 7lbs Abus Anchor or Kryptonite NYK FAI. The lock alone makes your bike heavier. Why would you invest so much money on a bike when you can just buy a bike that's ready with an IGH hub that has more than 3 gears? I sometimes do the Touristy thing with the Speed Duo where I live. It's a TON of fun, and it's a worry free bike because I don't worry about guys stealing it. That's my take on the Duo. What's yours?

NewEnglandCycle

In the next few weeks I will be upgrading the rear hub to a sram automatix and then keep the bike as is. It gets used to ride a fewblocks to the grocery and the like.