Can anyone suggest hub conversion kit options for a Dahon Helios P8 with 74mm front axle and 130mm rear?

[guerney]

@guerney The controller is squeezed in the small compartment at the front of the battery case.

That's got to be pretty small, not knowing much about KT kits, I would have assumed that a 15A controller would be larger than small enough to stuff into a small compartment. I Googled a bit last night, and the most powerful KT controller I found for 36V was rated 12A, but peak was higher. Which KT controller is it? Did you buy the display with the controller (also which display do you have?) from the same online shop? And could you say which website you bought them from?

The AKM100 hub isn't visible between the brake caliper and Cassette, so it's only the battery and a small handlebar display that shows its a conversion.

Your bike's electrickery is quite stealthy - if you cover the battery with pannier bags, it'd be hard to spot your bike's true nature. My rear rack battery is always covered with two waterproof rucksack covers, plus sometimes pannier bags, but there's no hiding the Helios' BBS01B lol. I'm reluctant to transfer that kit to the Espresso, because it took so long to get everything working and set up perfectly, and it hauls trailers up steep hills just fine... but coming down gravelly tracks on steep hills with those heavy trailers, is another quite alarming set of stories, hence my interest in larger wheels and wider tyres, for more traction.

 

[RogerA]

I bought the hub, controller and an LCD4 display about 2 years ago from TopBikeKit, but have had to replace the LCD4 as the buttons started misbehaving. I think water got in during a downpour when I was riding. I've now got an lcd5 that I bought off ebay. I built the wheel myself.
The controller is a T06S I think. 7A continuous (ie 250W @36v), and 15A peak. I'm not getting it out to check because it's a bit of a tight fit with the wiring and it would be very easy to damage a wire when putting the screws in that keep the compartment closed.

 

[guerney]

Yes if a listing doesn't show the RPM then one will have to go by the wheel size for a RPM listing. I would say 17a max for the lightweight hubs, even the akm100 is 20a max as many users on ES years ago including Cwah mashed the planetary gears with too much power.

If you want more power then opt for the AKM 128 for 25a.

How much power was Cwah running? Not having heard metal planetary gears in operation, I don't think I'd mind them, as they would alert people that something was approaching, however the reality might sound quite unbearable, if metal planetary gears for AKMs were available, or are indeed wise to use for insane levels of power.

I have used 20a at 48v on the Q128c and suspect 25a will be good as well.

That's impressive for such a small looking motor. To avoid having to upgrade my battery's BMS, I'd consider up to 18A if necessary, leaving an amp for all the extra lights (it's less than that) which will remain soldered to the Helios' battery. I've found exactly the same mount for my battery on ebay, dispatched from within the UK, at about the same price they're selling for on AliExpress, for the Espresso.

 

[Nealh]

I don't know for sure but expect it was 20a + , he and a few on ES wanted more power but the Q100/AKM100 couldn't take it. 17a is a max safe limit , the T06s comes in three flavours 15, 17 & 20a.

Topbikekit sell the gears anyway so easy to get hold of and may be worthwhile buying a spare set of gears to keep handy.

The Kt works very well so much so , that I only need pas 1 where I live or pas 2 sometimes towing the laden traier . For commuting a hub is by far the most relaxing way to go and a front hub is a good choice .
I can't fault my tiny Bafang g370 it is slightly smaller then my Alfinee 8.

 

[guerney]

There is a folding handlebar stem extension for the Espresso, which folds over backwards to the left at 45 degrees, tilting the handlebars to the side for a narrower folded bike profile... therefore fitting wide hoop trekking handlebars as linked below is an interesting possibility. The additional bar looks ideal for ebikers forever running out of space for lights, displays, ever more switches etc. (might just be me lol). Simply tilt the lot over when folding the bike - no need to add handlebar extensions, many of which turn and droop in the rain. I suppose the narrower folded profile afforded by the barmy 50cm handlebar this bike arrived with, was the reason why they were fitted, allowing this Espresso to fit into a car boot folded, without having to unscrew bolts to turn the handlebar every time. My main reservation, is that the folding mechanism adds two inches and a bit to handlebar height. Also, I wouldn't be able to fit Redshift handlebar suspension, which @Nealh said was quite good.

Cinelli Double Trouble Handlebar 660mm 31.8

The Double Trouble handlebar is the perfect trekking and touring handlebar. The bars can be mounted in multiple positions from upright for travel and bike packing comfort or angled for a faster more aero ride. There's also vastly increased space across the bar for not only hand placement but for...

bikeboom.co.uk

 

[RogerA]

I'm not sure if the Espresso is the same, but my matrix has an NVO stem (https://foldingbike.biz/epages/7665e38c-067c-4fa0-9037-afac2266f927.mobile/en_GB/?ObjectPath=/Shops/7665e38c-067c-4fa0-9037-afac2266f927/Categories/fcd04e26e900e94b9ed6dd604fed2b64/NVO_Handlebar_Stems&Locale=en_GB), which means you can loosen the stem bolts and then the whole stem/bar assembly comes off without having to adjust the star fangled nut.

 

[guerney]

I'm not sure if the Espresso is the same, but my matrix has an NVO stem (https://foldingbike.biz/epages/7665e38c-067c-4fa0-9037-afac2266f927.mobile/en_GB/?ObjectPath=/Shops/7665e38c-067c-4fa0-9037-afac2266f927/Categories/fcd04e26e900e94b9ed6dd604fed2b64/NVO_Handlebar_Stems&Locale=en_GB), which means you can loosen the stem bolts and then the whole stem/bar assembly comes off without having to adjust the star fangled nut.

Very interesting, thank you for pointing the NVO stem out. I'll ring up and ask them about that.

It looks likely to me that the fangled nut would need to be removed (if one is installed), before this folding handlebar gizmo can be inserted:

Dahon Espresso folding Handlebar Stem 2005 (pre- A head style)

Folding Handlebar stem complete for 2005 Dahon Models like Espresso. 11/8" quill type fitting. (not A-head) Integral bar is used to unscrew the top cap to allow the handlebar to fold down neatly.

foldingbike.biz

If I buy a new fork and frame, they'll be shipped unassembled. I really don't fancy installing the fork myself, because of the horrible consequences of getting it wrong. Luckily my local bike shop is very local, unluckily as usual he'll rob me blind, but luckily he's thousands of years old and knows his stuff. His shop's been there since 1890.

 

[RogerA]

That folding stem is an old style quill stem rather than a modern Ahead style. They are not interchangeable, so it will depend what type of fork you have - threaded or not.

 

[guerney]

White's did seem to think the folding mechanism and Espresso fork they have for sale are compatible. I love the idea of a folding handlebar, I don't think I can resist at the very least trying it, because it's an ingenious design which means I can get away with using ludicrously wide handlebars for stability and all my gizmos, yet the bike could be quite narrow when folded. A more upright position could make a nice change from crouching, but I suppose if I didn't like it, I could replace the handlebar folding mechanism with something else (or from the large Espresso I have, Espresso fork design changed over the years, I was told the newer ones use Ahead). I don't know if stem adapters are any good:

Velo Orange Threadless Stem Adaptor

The VO Threadless Stem Adapter allows you to use threadless stems on bikes designed for a quill stems. The advantages include the ability to use commonly available threadless stems with a variety of rise angles.

freshtripe.co.uk

 

[guerney]

The Dahon Helios' conversion to a non-electrified bike, to AKM hubbed electrified will take me ages, but while finally getting around to looking at my £72 ebay Espresso supposed bargain (I wasn't expecting to win that auction lol, it caught me by surprise), I found that the front derailleur had completely seized with rust (Shimano Tourney, the rear was fine but rusty)... After removing both to remove rust and lubricate, the front would not budge, so I soaked it in a vinegar bath and when that didn't work, I applied a lot of WD40 and left it for a few hours, and when that didn't work I started freeze/shrink and heat/expand cycles with liberal applications of WD40, alternating between the top of my living room radiator and kitchen freezer. After an hour or two of freeze/thaw and generous WD40 squitings in between, plus scraping off rust around but and bolt contact points gently with a scribe for better WD40 penetration, I was finally able to get the darn thing unseized and rotating (it's dual arm). However, whether I can get this front derailleur moving freely, smoothly and springing back, remains to be seen, and I'm rotating like crazy every so often and liberally applying WD40 to see if it'll happen. It seems structurally sound, but I may decide to simply buy a new one. The ebay seller's husband Percy, his Mum or brother had clearly left this poor bike out in the rain far too long sometime(s). The other rusty bits dissolved to be a bit cleaner with applications of vinegar, or after being soaked in a vinegar bath for about 30 minutes, then rinsed and scrubbed with cloths. Percy's late dad looked after his bike: the wheels are still quite true, the rusty old chain shows no stretch, and under the rust, the rear cassette looks unworn. I really hope this bike isn't haunted.

 

[guerney]

After squirting all available WD40 over the front derailleur and leaving it totally soaked since Friday, upon trying to turn it by hand today, a big chunk of rust fell out from between the springs, and now it snaps back cleanly. The action is very smooth, but I'm going to wash the WD40 off, soak it again in the vinegar bath and resoak and clean it etc. before re-attaching it to the old frame... or I'll order the new frame and fork, haven't decided yet.

A brand new frame would look all shiny, and well... new.... and attract thieves. Not many would want to steal the sctatched up old one. On the other hand, a smaller frame will weigh less. Not that I care too much about weight, it's a BBS01b.

Whether choosing old frame or new, I'll definitely get the folding handlebar headset, because I can't resist. Unsure of what size handlebar the folding headset needs, yet. If 31.8mm, wonderful there's oodles of those, including the trekking hoopy handlebars I have my eye on. If not, I'll have to get a bloody long handlebar, or one with a bracing strut in the middle to attach the DPC18 display and gadgets to. The folding handlebar headset raises bar height by a shade over 2 inches, so I'll need flat bars I think. Do horizontal lowered handlebars exist?

These look a bit bonkers (not as bonkers as butterfly handlebars, which I've ruled out because I'd need new rear view mirrors, which is another ball game), but my twin 1800LM headlights could be perched on the front prongs...

Surly Moloko Steel Bicycle Handlebars - Trekking Bars multi hand positions 31.8 | eBay

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www.ebay.co.uk

 

[AGS]

Vinegar baths may take a day or two to work properly. Half an hour soaking isn’t long enough for the acetic acid to eat the rust.

You could try something like this if you are impatient and want to speed up the process:

Fast Attack Super - Acetic Acid5L

Fast Attack Super is a high strength proprietary acetic acid blend. Acetic acid is a colourless liquid widely used as a cleaning component. We provide a premium quality Acetic acid blend that has properties to kill fungus and microbes, it is a powerful acetic solution useful for combating...

www.jennychem.com

And there are plenty of other chemicals on the market that do the same thing. But they are all expensive compared to the price of vinegar. I use Lidl vinegar because it’s the cheapest I could find.

Citric acid is supposed to be good for rust removal as well, but I haven’t tried that because it’s also more expensive than vinegar.

 

[Nealh]

Vinegar is a weak dilution of acetic acid typically 5%, in my beekeeping I use 80% acetic acid for sterilising which eats metal so I have to use vaseline over some metal runners to stop them rusting/pitting heavily.
Safer to stay with low % vinegar and prolong the immersion .

 

[guerney]

Vinegar baths may take a day or two to work properly. Half an hour soaking isn’t long enough for the acetic acid to eat the rust.

You could try something like this if you are impatient and want to speed up the process:

Vinegar is a weak dilution of acetic acid typically 5%, in my beekeeping I use 80% acetic acid for sterilising which eats metal so I have to use vaseline over some metal runners to stop them rusting/pitting heavily.
Safer to stay with low % vinegar and prolong the immersion .

Thank you for your advice! Three weeks ago while attempting to buy Wilko's cheapo bicarbonate of soda, I ended up buying their cheapo citric acid granules (because they had run out of bicarb) which I was getting around to descaling my stainless steel electric kettle with. There is the risk of pitting with that too:

Quite why Wilko thought it necessary to switch the colours of their boxes of bicarb and citric acid for each other's, I don't know. Family owned business = odd decisions.

 

[guerney]

This photo could trigger persons sensitive to the sight of unclean bike parts. You have been warned.

I didn't photograph it's original state, but here's the current "Before"pic, taken after my cleaning efforts so far. Seems to work fine, despite how this looks. I'd like to stick with the existing front and rear Shimano Tourney derailleurs for now, because they can handle up to 34T rear cog, and better options appear to be (to me at least) a little thin on the ground for the 3 X 7 speed Espresso.

I read about someone getting all 9 gears working on his bike, which he'd fitted with a 11 speed Shimano Deore rear derailleur, by using a 1:1 SRAM X5 nine speed shifter.

 

[guerney]

Using what I had in the kitchen: I didn't want a multi-stage process, so went with two ladlefulls of bicarbonate of soda boiled in a small amount of water, which turned out to be beyond the saturation point of the quantity of water used, evidenced by some not dissolving. Separately, I mixed 250g of citric acid with about the same quantity of cold water in a deep 1.8lr white plastic tub, it dissolved easily.

When I poured the dissolved bicarb into the tub containing citric acid, there was a lively frothy reaction... I really should have worn goggles. To further degrease (bicarb degreases, citric acid doesn't) I also added a capful of concentrated washing machine liquid, then threw in the derailleur and left it for half an hour, then an hour... four hours later, it loked like this. Not a hint of grease anywhere, still some rust but that's as long as I'm risking soaking it. I expect the PH of the combined solution was acidic.

I'll abrade some remaining rust off. The printing has dissolved a little - the Arm and Hammer Baking Soda toothpaste I scrubbed it with afterwards using a toothbrush (I should have used my electric toothbrush, but I couldn't locate the spare brushes I bought with it three years ago), may have contributed to it's partial erasing. When it's completely dry I'll cover it with some 3 in 1, or maybe Hypoid 90. It appears to work even better than before.

Oddly satisfying.

 

[guerney]

I've decided to convert the Espresso to hub drive instead. The Helios with Bafang BBS01B just works. It does everything well, apart from steep gravelly descents when heavily laden, which I can avoid by taking a short detour through a golf course inexplicably situated in a nature reserve, when hauling spring water from the natural springs at the highest point within that nature reserve, to grow my pumpkins with. Plus it's fast, folds small enough for commuting, and I'd only be shaving about 2kg from it's weight by converting the Helios to hub drive anyway.

Thank you to everyone who responded to my questions on this thread, which will be useful for the Espresso conversion.

 

[guerney]

THINstem

Affordable, safe and simple quick-release folding stem replacement that makes your bike over 50% thinner giving you the freedom to take and store your bike anywhere. Prevent theft, store neatly indoors. Easily get in and out of places. Move easily in crowds.

www.revelo.ca

 

[guerney]

It seems quite easy for hub motors to be stolen. Even if the D lock goes through the frame and rear wheel for example, the hub could be wire cut out. But I think it unlikely thieves would bother.

 

[guerney]

Are you sure it's a130mm rear spacing? I've converted a Dahon Matrix which looks like the same frame and that was 135mm with an 8 speed cassette. I'm using an AKM100CST hub with a 15A KT controller and it'll cope comfortably with 15% gradients on road. I've removed the front triple and have a single 42T ring with guard. I've set the speed cutoff at 20kph because I only want hill assist but I can comfortably pedal at 25mph on a slight downhill.

Did you install the 201rpm version of the AKM100CST, or did you go with the 328?