have u found wheelset for small wheel that can accomodate 11s?

i will go for Dura 9100. the shimano Di wireless sistem are not so wireless like Sram

wow..that is big amount of money.what is ur purpose?

racing?
leisure?
commute?
style?
touring?

if rb look, u can find minivelo. but if ur looking for minivelo that can fold, few model i can listed such as
1. tyrell fx/fsx
2. alex moulton
3. dahon dash
4. doppleganger X
5. pacific reach

all model above got toptube and downtube. but if u wanna find folding bike with dropbar

6. tern x18
7. anemos

but, if ur planning on buying on folding bike and convert to dropbar,
anybike will do depends on ur personal preference.

but bare in mind, all model above is not compact when it fold as brompton especially when u convert flatbar foldies to dropbar, really take some space there.

Just a suggestion.

Get a Verge Frame, change ultegra groupset,light wheelsets, handlebar, seatpost, saddle, i think u'll get similar performance with the x22, and probably will spend less money for it.

Nope. Have to get the whole bike. Frame can search for fnhon.

What i mean is, all the verge series is highly likely using the same frame anyway, and the highest spec comes with a very hefty pricetag. The cheaper way to achieve that spec is, to buy a bike with similar frame and upgrade the parts and components independently. I think that is what sifu azam did to his bike.

Cousin to that verge series frame is the dahon vigor frame.

most 20er folding bike comes with 52t single chainring and 12-32 cassete.good enough for beginner but for long distance and long dragonback climbing, a double chainring setup like 53/39 or 52/36t will help a lot

here a tips,
mostly all gear part from rb can get into ur foldie. in this case, u can upgrade ur rb groupset and transfer old one to foldie. problem is, please avoid 50/34 crankset as it wont give u enough gear for topspeed.

another problem will come, if u want to used flatbar shifter on foldie when u had dropbar sti. when it comes, money is the answer

do remember shimano road component (high end especially) cannot be mix with shimano mtb component. i may work, but not smooth as butter. sram component can mix and match without a problem. campy?freehub body for foldie are hard to find, unless some modification.

there are 2 type of common modification done on foldie.
1. single chainring
most of them want to keep it minimalist and light thus eliminate the fd and 2nd chainring might gave u a bit lighter setup. but do keep in mind, most single chainring used mtb ratio casette to keep enough wide range gear for most condition

2. double chainring
most of them will setup with rb casette ratio as they had another life saver 2nd chainring. still, there are few person still want wider gear by adopting mtb casette.

its all up for personal preference. u wont know until u try and feel it urself.

Oval? As long as you are happy.

53/39 ? This you must ask your legs, nobody can answer for them.

Chainring up to 60T are available. Try hunting from BBS . Offline can ask local bicycle shops, very popular with mosquito bikes.

https://bicyclebuysell.com/item/440247/fsa-...less-than-200km

saw 1 selling on bbs...go grab it...and donate your old 1 to me