Folding bike modification questions
 

Hi

I'm looking to purchase two folding bikes and have a couple of general questions about making modifications.

General questions:
Wheels:
1. Can i replace bike-frames fitted with 451 wheels with generic 20" wheels ?
2. Can i replace 20" wheel bike-frames with external / derailer gears with a rear 20" gear hub wheel ?
3. Can i replace generic 20" front wheels with a 20" electric kit wheel ?
Handle bar posts:
4. Some folding handle bar posts dont have an ability to adjust and are of fixed length. Can i remove any supplied fixed handle bar post and fit with an outsourced adjustable one ?
Breaks:
5. On 20" wheel frames can i replace generic lever breaks with disc breaks ?
Weight:
6. I've been told that indicated folding bike weights often leave out weight of items like pedals, handlebars, kickstands and other items. Is there a general rule or formula when trying to figure out real weight of a folded bike when looking at specs ?

The bike models i'm looking at are listed below and also any advice or links to recommended modification products welcome.


1. Carrera Intercity
2. Dahon Mariner D8 2018
and
3. Euromini Liberte
4. Tern Link D8 2018
5. Tern verge N8 2018


Thanks alot for your time and attention. Appreciated.

sp

I'm not sure what the point would be of making all those changes instead of just buying one set up the way you want, but:

You can drop from 451 to 406 with v-brakes if you have some adjustment left at the bottom of the pads' slots. You can convert derailleur to IGH, but you'll need some way to tension the chain like a Shimano Alfine or Paul Melvin tensioner, or just leave the derailleur on to take up chain slack.

Yes, you can swap handleposts. I just put a one-piece on my new Mariner 8..I don't like telescoping posts. No, you can't retrofit discs without some serious surgery on the frame.

Where did you source replacement posts from ?
I'm not looking to make all those mods. Depending on which two bikes i end up buying, i may need to do one or two.
But from my shortlist these are the kind of things i would want to do.

Thanks
sp

I swapped amongst bikes I own, but you can get handleposts - and just about anything else you can imagine for Dahon/Tern - from Thor USA.

http://www.thorusa.com/accessories/handlebar.htm

1. It may be possible, but you need to think about the brakes, and decreased bottom-bracket height. The caliper brakes on a 451 wheel will not reach the smaller 406 wheel so you'll have to get weaker long-reach calipers, unless the frame has mounts too for v-brakes. The other concern is that you will be lowering the bike since you 406 is a smaller wheel than 451. For example, my 451 wheel bike has a 37mm wide tire, yet the wheel is a full inch or 2.5cm taller than my bike with a 42mm 406 wheel. This may have implications for handling and pedal strike with the ground.

At a considerable markup. I just bought a litepro dahon spec post from aliexpress with free shipping $55 vs Thor USA $75 and shipping would be at least another $40 according to his faq, so $55 vs over $100 for an identical part...

Well sure, if you shop around the 'direct from China' sites you may find a better price, but that's no reason to come here and act like Thor is ripping people off. And if you're getting $40 shipping from him, you're clearly not in the USA. Buy from somebody else and be happy.

If you change the rear wheel you may run into problems if your frame has 130mm dropouts and your internally geared hub fits in a 135mm frame.

You can always lace a hubmotor into a 36 hole rim, so wheel size shouldn't be an issue. Be aware that most front hub motors are typically 100mm so you require a fork with a compatible dropout width. I believe there are some narrower motors. Steel forks are always preferred too for strength. There are so many caveats with front motors, I believe it's better to put them in the rear.

Thanks everybody - but keep it coming...

Didn't realise there were issues with motors on the front wheel. Blackfriday have a video of a front fitted motor they're now doing which looked pretty nifty.

......

It can be done - I had a 250w front hubbed Brompton - but Dahons and Terns have very narrow front spacing. I just put a 750w mid-drive kit on a Mariner 8..much simpler install and WAY more power.

I wasn't saying anything apart from pointing out there are far cheaper options. However since you got all defensive Ill bite. What is the extra cost for then?? Same part from china, what extra do you get for your money? Because if you get nothing at all for a near 100% price increase I think most people would say that is a ripoff.

My uneducated guess is that you're paying for his knowledge and expertise. While you may know exactly what you need, I may not, and would greatly appreciate knowing what will, and will not work. I also expect that you're paying for basic customer service: if something doesn't work, they'll take care of it. In my experience, you will no get that kind of experience buying direct from China. Whether that's worth the additional cost, mind you, is entirely up to everyone to decide for themselves.

You said "at considerable markup", which clearly implies you have a problem with Thor's pricing, then threw in a weird reference to shipping across an ocean like it's his fault it costs a lot. So I reject your inference that I'm "defensive"..the OP asked me where he can buy handleposts and I gave him a source I'm familiar with. You can easily add your own information without disparaging mine, but this is Bike Forum where everybody has an axe to grind.

I'm reading a bit about bikes made in China suffering metal fracture. The quality control isn't always there in Chinese manufacturing and one's assuming the American outlet is offering some guarantee of quality, but perhaps this needs to be clarified. (Do) Aliexpress offer some kind of guarantee for their products too i think (?) I feel abit like - i once had a bike that snapped in half on me when i was riding it and i can't afford for that to happen again so i'll pay for quality made parts.

I think you can assume the exact same part from different sources is built the same way, but "I think" is the problem. Products like folding frames and handleposts are high risk items and I prefer to buy them from people I trust and can talk to. If that means an extra $20 to Thor - a guy who does business in my country and always answers my emails - that's money well spent.

I too will vouch for Thor. I don't think his prices are that much higher than alleged. He is fair and stands behind the products he is selling.

Wheels:
1. Can i replace bike-frames fitted with 451 wheels with generic 20" wheels ?
>> You need to consider if your brakes will still touch the 20" 406 wheels. This is usually done the other way round, from 406 to 451.
Why not just buy a 406 wheeled bike?

2. Can i replace 20" wheel bike-frames with external / derailer gears with a rear 20" gear hub wheel ?
>> 20" IGH wheel is possible (need to consider #1 too); Your need to consider the OLD though.
Don't know about the RD + IGH

3. Can i replace generic 20" front wheels with a 20" electric kit wheel ?
>> There are such kits about on Taobao, Ebay, Aliexpress.

Handle bar posts:
4. Some folding handle bar posts dont have an ability to adjust and are of fixed length. Can i remove any supplied fixed handle bar post and fit with an outsourced adjustable one ?
>> Usually yes, unless your bike has a special one that can't fit a 'generic' 3rd party one

Breaks:
5. On 20" wheel frames can i replace generic lever breaks with disc breaks ?
>> Only if your frame/fork has the mounting points.

Weight:
6. I've been told that indicated folding bike weights often leave out weight of items like pedals, handlebars, kickstands and other items. Is there a general rule or formula when trying to figure out real weight of a folded bike when looking at specs ?
>> Usually its declared w/o the pedals, so you still get a rough idea how they compare across brands/models.

I was producing a long post countering all the strange points bought up here (like the No1 store for litepro parts sold with a full guarantee isn't as trust worthy as a tiny shop on the other side of the planet to the manufacturer) but Ill let this do the talking:

Litepro brake levers:
Aliexpress:
https://www.aliexpress.com/item/litepro-ultimate-7075-Aluminum-CNC-MTB-V-Brake-Lever-Mechanical-Bike-Brake-Lever-3-Fingers-Design/32550761530.html?spm=2114.search0604.3.16.43106622wO9uIl&ws_ab_test=searchweb0_0,searchweb201602_5_1 0152_10151_10065_10344_10068_10342_10343_10059_10340_10341_10696_100031_10084_10083_10103_10618_1062 4_10307_10623_10622_10621_10620,searchweb201603_50,ppcSwitch_4&algo_expid=50801559-77a3-490d-a2b2-ba4c9e3eb29e-2&algo_pvid=50801559-77a3-490d-a2b2-ba4c9e3eb29e&transAbTest=ae803_1&priceBeautifyAB=0
$22.50 with free shipping anywhere.

LitePro Accesories/ Crius Bikes and frames
$139.00 Plus shipping.

In response to one poster here who says its only an allegation that thors prices are rather high I was going to go through them one by one. But those levers were the fist I checked and well... If you guys want to pay an extra $110+ USD plus shipping for "expertise" than go ahead. My Veno CNC levers made in Japan just down the road from where I work were cheaper than what ThorUSA is charging for those Litepros.

Dude, I can't be any clearer. I live in the USA and I gave the OP an option based on where I live and what I know. I don't personally give a damn where he or anyone else shops, I was just trying to help. All you gotta do is offer your options from your experience, too. This isn't complicated.

thanks useful links - i use aliexpress for other stuff because it typically undercuts retail prices back home- ill check it some of the bike gear available....

More links welcome.....