V1LLAGE_ID10T

First post. New account.
I recently have fallen into the world of cycling a little over a year ago and I owe it all to The Brompton. It reignited a love for bicycles I didn't have since I was a kid and that's what brings me here! When I moved to the city for work I sold my car and Needed a way to get around and the Brompton ended up being perfect for what I needed. Since then I have gotten myself a 2016 Salsa Colossal Ti Gravel Bike for more long distance leisure rides but the Brompton still remains my favorite for being the folding bike that people don't give me problems with when I bring it into places. Still it's not perfect (no bike is no matter how much we try convince ourselves at great expense), Now that I'm dealing with the cold and the rain and frost disk brakes are becoming more of a priority. Some hills I simply don't handle well despite riding for some time now so I'm looking for a greater shifting range and a. I want to go greater distances so I am looking ata 20 inch wheelset upgrade too. Finally to compensate for the weight gained with such parts I'm aiming for an all titanium frameset.

To sum up my build plans:

• Titanium frameset with fork and rear triangle for 20 inch wheelset. I want to lighten my load for the hills a little as well as not have to worry about rust.
• DIsk Brakes (Mechanical over hydraulic unless other Brompton folks have a strong case to go for hydraulic)
• Rohloff hub for handling hills up and down. Looking for thumb shifters All the ones in my research seem to be no longer in business.
• 20" wheelset I want to have greater rolling resistance and not have much fear of the terrain. I also believe this will cause less issues with the hub.
• Chain, no belt - I was first looking into a belt drive but it's looking like more trouble than it is worth to go for that. I am aware of kinetics offerings on this, but there still seems to be a lot of headache in this place especially for titanium.
• Where and when to carbon - I keep hearing about flex concerns and need more information on this. Brompton's t-line seemed to have chosen a carbon for for a reason enough to change the stem for it too. Not to mention on other parts outside the frame (crank, handlebar, stem, etc)

Feedback is greatly appreciated as well as part suggestions. The aim here is for something akin to a Subaru WRX. A good all rounder but not "the best" at any one given thing. A Brompton as an endurance bike with greater speed and rolling resistance I think would be the accurate description. I have been lurking these forums and trying to do my research, but I welcome any and all input on this. Whether I get feedback or not you bet I'm going to build this! Thanks in advance and wish me luck!

univega.duder

I’d be tempted to get a Helix. It’s got 24” wheels, it’s titanium and has much more flexibility than a brompton in terms of drivetrain options. I don’t know that it will work with a Rohloff but it does work with an Alfine 11 and I saw someone built one with the Kindernay hub.

Jipe

The Helix is heavier than the T-line and folds bigger, its not comparable at all.

About the Rohloff, the standard shifter is the best, its lightweight, simple, reliable and allow to shift several gear in one turn.

For the 20: wheels, due to its folding geometry, on a Brompton increasing the wheel diameter automatically increases the folded length and height (which is not he case with the Birdy).

Now that there is the T-line, the titanium clones just cannot compete, they cannot provide the same riding performances with the same weight.

Jonesandrew

Helix say the Rohloff won't work because it interferes with the fold. Can you share the source the information about a Helix with Kindernay?

tcs

I made a Venn diagram of what you want vs. what the trifold market is currently offering.



Anyway, here's some food for thought:

An alloy-framed Alps with discs and Shimano Alfine 11:



Here's a Leggero full-titanium:



An all-carbon Chedech:




And an unidentified AliExpress/Alibaba ti trifold with 20s and discs:

Jipe

The problem is probably the external gearbox of the Rohloff with disc brake, located on the left side of the bike (while other IGH have their gear control on the right side). Some people manage to have disc brake on the hub with the Rohloff internal gearbox.

Kindernay has an hydraulic gear command instead of cable(s) which is stupid, its only heavier, requires maintenance and prone to leakage while it provides no advantages vs. cables (there is no wear like with brake pads).

Reddleman

Have you considered Vello’s titanium framed folders as a starting point? A reasonably tight fold for 20” wheels and a frame built for disc brakes. Apparently the steel frame is a pretty stiff ride so the ti option should mellow that out a bit.

Jipe

and a flat rear tire

tcs

It looks like ( ← speculation) that's the regular 16" main frame geometry with larger diameter wheels stuffed underneath it. If so, that would significantly change the height of the bottom bracket and the position of the rider.

tcs

If the Burke 20 exists in R/L, it might suit your desires.

https://www.seattle-cycles.com/shop

V1LLAGE_ID10T

I personally am not interested in the Helix for two reasons. While it's the best fold I've seen for a full sized bike I think it's simply too big and the current trickle of bikes being produced makes me see growing pains. I'll wait for more people to adopt that bike. The second thing is I love the brompton for it's easy wheels and doubling as my rolling luggage when I need it to. hence why im more interested in upgrading/building one of my own instead of alternatives. I simply haven't found one that has the same fold acceptance factor.

I'm not looking at titanium to build the lightest bike as much as compensate the weight of the added parts and also no longer worry about rust.

I've been exploring quite a few options. I'm currently looking at a few pages of singapore bike dealers and a couple aliexpress framesets using Gr5 material. I've actually seen all those items you listed and more which is why I'm looking at building. Disk brakes are a big plus for me where I live unless someone can convince me of a better pair of rim brakes that can handle the task. Youtube Dahon Curl I8 Brake Effectiveness to see my concerns (can't share links since I havent make enough posts yet)

Again the fold isn't the same as the Bromptons with the rolling wheels. The closest I've found is Bridy's and Iruka S which uses an Alfine hub and both use aluminum frames. Rust proof sure, but not nearly as effective as ti or carbon.

Youtube 20 Inch Trifold! Full Titanium, 11 Speed Ultegra! Hubsmith Carbon wheelset, All high spec (again can't post links yet sorry!). This eased my concerns about the folding on a larger wheel size.

I'm pretty sure the place is closed down. I sent an email and tried making a phone call a while ago. Even still my folding expectations aren't quite met here.


I've also considered SILVEROCK's Carbon front fork and rear triangle but the options only are offered in 16" size. The Ti bike builders I talked with did concern me about apprehensions using ti forks especially when using disk brakes on a smaller wheel size. I'm convinced Brompton thought the same.

univega.duder

here’s a few photos and a link to the users post on instagram showing the Kindernay on their Helix. It doesn’t seem perfect as hydraulic lines were zip tied to the frame but still neat to see.

silverx

I use 12s axs on my helix 😊

Jipe

Yes, the same problem exists with he 20" conversion of Kinetics and 20" wheels also increase the wheelbase, folded length and folded height (the amount depend of the overall wheel diameter, i.e. of the tire width).

Is this bike really available, I haven't seen anybody having one?

V1LLAGE_ID10T

Made a reply but I think I need to wait for mod approval still. Making this test post in the meantime.

tcs

Ha! That guy doesn't even know how brakes work (he gets the physics wrong.)

The first Curls were fitted with two-finger brake levers and long-wearing pads. Oops! They fixed those issues some years back, as can owners of the early Curls.

V1LLAGE_ID10T

The main concern I have is given the wet weather and snow I deal with disk brakes seem to be a necessity unless v brakes are more capable of handling the elements better than I have been lead to understand on the whole. If v brakes are enough that solves a few problems for me but I'm cautious nonetheless.

tcs

Hey, I'm there with you. I've ridden caliper-braked bikes for over a half-century, never a problem, and considered discs just some new whizbang gimmick to sell something new to somebody. Then during COVID boredom, I built up a bike with discs. Word. Now I'm with those who say 'no new bikes for me unless they have disc brakes'.

It's not just power. Bicycle brakes can be too powerful (re: stoppie, or initiating a skid in wet weather or snow). I like the finely controllable modulation on my discs.

Jipe

I fully agree with you wrt. the finely controllable modulation of discs but not all of them: I only had this with the several hydraulic disc brakes I have/had (Shimano Deore, XT, Magura Louise, MT4, MT5, Avid Code and SRAM Guide but those two last one are very bad on some other points), not with the mechanical disc I have (TRP Spyre) or have had (Avid BB7).

univega.duder

Not to derail the thread but curious what cassette your are using with AXS on your Helix? The largest cassette that’s compatible according to the Helix site would be 9x42 with chainring no larger than 36 teeth. It doesn’t seem to be possible to put on one of super wide range cassette.

univega.duder

Have you checked out the Eerdermetaal Brompton mods with 20” wheels? Seems like he’s not taking new orders at this time but if you want 20” wheels like that could be an option? Or
Kinetics in Glasgow. I do wonder how the addition of 20” wheels would grow the size of the bike? At that point I feel like it might match up closer in size to the Helix. I agree the Helix bike is still getting going and doesn’t seem fully on their feet yet as a company. They did recently make available rolling wheels to make
it easier to roll when folded. I’ll be curious to see the folding rack when that’s finished and hopefully fenders.

https://www.eerdermetaal.nl/brompton...collectie.html

V1LLAGE_ID10T

The Eerdermetaal I am not so enthusiastic over. Not a fan of wide tires. I've checked out kinetics and was initially going for their 20 inch kit with the rohloff and calling it a day. The problem is I grew up in the salt belt and where steel will rust and is heavy than alternatives and it's hard to convince my brain otherwise. My gravel bike that I use for a speedier ride is ti save for the carbon fork so I'm now more convinced than ever.

79pmooney

The salt belt? Michigan? (I've wintered in Ann Arbor. Pretty sure the city road crew has an in with someone in atmospheric sciences at the University. When snow is forecast, he gets an estimate of how many snowflakes are going to fall, then matches that number 1:1 with salt crystals.)

Not much to add here on the bike except to say I'm in your corner. I love going down the path to a solution that will do just what I want it to. Yes, usually more work, more money spent, but when I've gotten it right, truly fun! I set up a broken frame I picked up for $20 as a fix gear. So much fun I had from the BB forward copied, a totally custom arrangement for the dropouts and stays, then that built out of titanium by a local builder. 12 years and 20,000 miles later, my favorite bike.

silverx

I am using sram force 10-30t with 50t chainring
From helix upgrade guide show simple calculator to prevent chain hit frame
Example if following helix website, 10-30t supposed use 48t
But i try use 50t still ok (maybe this max size for 30t cassette)
If u want use bigger chainring must use small cassette

ipostnak3d

hi there. i have seen a lot of TITANIUM COLOR bike frames out there, painted alloy frames, not actual titanium material frames.

for exaample the FNHON GUST and STORM models of folding bikes, they come in this awesome TITANIUM COLOR.

does anyone know what colors (varnish) to mix to get this look?

i have looked everywhere on the net and youtube and cant seem to find a tutorial.

i thank you in advance!