Well a nice green frame arrived yesterday!


I was keen on a Birdy after riding one in Japan but they're quite pricey and shipping from Singapore to NZ seemed difficult and expensive and the essential rear rack wasn't in stock. The FN Hon GT 20 also seemed a bit difficult to ship. The FN Hon Storm frames on Ali Express didn't seem to have a pig nose, and having had the Terns for a few years we thought a different fold might be interesting. So we thought we'd try one of these. I did read all the helpful comments on the similar Al Packa including Dave's "neither fish nor fowl" but think this might suit our use (not commuting, not much multi modal, folding for eg car or cab convenience and particularly for overnight security while travelling)


We're now looking at:

- wheels and tyres - thinking 2.4inch tyres for trails

- drivetrain - considering putting the schlumpf on - I really like low gear to be less than 20inches, and it did me well on the Tern in Japan on steep hills, but just a 1x10 is nice and simple

- racks - TQIQT do a rear rack that might work with panniers ok, I'm hoping my Spartan front rack might cope with a wide tyre. The pignose bolt holes don't line up with the Tern luggage truss so I guess its a brompton fit. Might go for a brompton style block - their bags look good, not so sure about their front racks.

- mudguards for those wide tyres


Any thoughts or advice appreciated.

When there is some progress I'll try to post a photo.


Cheers

11-46T or 11-50T, 10-speed cogset with the Shimano Deore M6000-GS RD.

That's fantastic range. On the 50T cog, RD looks great. Middle of the range where I'd spend most of my time and the RD cage vertical... ground clearance is OK with those fat tires. Might be sketchy with the 1.5" (just using up old stock from bikes) and 1.75" I usually run, hoping to eventually use 2.0", I think will clear the frames, but I have lots of smaller factory rubber to use up from other bikes, the bikes have fine shelf life but the tires don't, so might as well use them on my primary bike. They'll all need lower gearing, will probably go 1X if they have 8-speed (and larger) freehubs.

The OP's build will be interesting, as the frame photo online shows an unusually tall seat tube and fork steer tube that each clamp around shorter posts, instead of typical long telescoping seatpost and folding handlepost. So not sure how compact those fold. EDIT: Ahh, things are Bike Friday style, seat tube folds forward, handlepost comes out. Also notice unslotted dropouts, if thru-axles, unusual in that it has no disc brake caliper fittings, maybe it does, as I see no v-brake posts:

Based on actual experience, a potential problem -- something to watch out for -- with a 50T cog (coupled with a larger T chainring) is the chain rubbing against the seat stay. Caveat emptor.



I wouldn't go to a 50T cog on anything but 2.30" meat or wider. Again, based on actual experience, here's the worst-case ground clearance with a 11-50T dish.

I'll take your word for it. Surprises me, especially with wider seatstays for tires, but looking at my folder now, with low folder seatstays, yeah, I could see that.

It's nice to have plenty of options available these days.

I have a Bike Friday All-day with a frame similar to the All-packa.

For the mudguards for 55x406 tires, I mounted SKS Bluemels Basic 20" 60mm they are excellent: good protection, fits well and not too heavy. Its easy to reduce the weight by replacing the stainless steel rods by titanium rods (like done by Brompton for the lightweight mudguards of the P-line and T-line).

For the rear rack, the folding rear rack of Bike Friday is very heavy, to keep the weight as low as possible I mounted a Tubus Airy titanium rear rackl it weight only 280g on my bike (the actual weight depend of the mounting small parts, the mounting tubes provided by Tubus are heavy), accept a max load of 26kg and allow to mount full size rear pannier. Its designed for 26"-28" wheels but not higher than the Bike Friday folding rear rack and just high enough to carry full size rar pannier.

Of course, I don't know if these components are available in New Zealand?

For the transmission, a good solution to reduce the weigh on a folding small wheel bike is to use a rear wheel with an XD or XDR freewheel body and a cassette starting with a 10t cog what provides a wide gear inch range with a smaller biggest cog and long enough gear inch with a smaller chainring,

Thanks for your comments Ron, Duragrouch and Jipe - will look into the 50/11 and 46/11 setups, maybe also the extra FD that Duragrouch has talked about elsewhere, if 1x does end up too tight. The frame tubes are not big diameter so FD may be possible. But then I have the schlumpf on hand ...
The SKS mudguards and titanium tubus rack look great but don't seem to be readily available here and the latter looks to be more expensive than I had in mind - nice tho! Interesting that the BF rack is very heavy, though most things from USA are pretty expensive by the time they get here anyway

How much did you pay for the frame in SG (not the price delivered to Aotearoa)?

Many rear racks will work, but in my experience, the key with a 20" folder with shorter chainstays than a 700c touring bike, is a rack that fits far enough aft for heel clearance with panniers (gold standard for 20" wheel is front of panniers even with rear axle center), and high enough for curb clearance with full-size panniers. (The rack that came with my bike was centered and low over rear tire.)

I got lucky when I first set up mine, a former discount seller had Blackburn TRX-2 commuter racks designed for bigger wheels for dirt cheap clearance price, they only had disc version available which I didn't need but bought anyway. (These had a clever storage feature for a U-lock but which was notorious for breaking, but the rest of the rack is strong and solid.) Heavy, but the well-aft position I needed.

TRX-2 no longer made, but last I looked, Axiom made a rack with interchangeable lower attachments, so you could achieve centered or well-aft of wheel if needed, in narrow or wide top deck for trunk bag. But with rack well-aft and lower chainstays on a 20" bike, I needed extra-super-long front attachment stays, much longer than came with the rack; Available aftermarket from Jandd, or I think also Topeak, $USD10-12, both were available at my local bike shop. They were wider than the slots for them on the rack, but I left them straight and attached to the rack at a deck crossbar using rubber-covered stainless steel P-clamps (various sizes available cheap at marine (boating) supply stores), which was also at a better angle to secure the rack fore and aft, perfect.

Never any stability issues at all with a heavy load that far back, and, the rack acts as landing gear with my bike folded and tilted back, as in the normal folded position, the aero bar on my handlebars was dragging on the ground.

Here's my bike with the Blackburn rack on its first mini-tour to meet someone for a week, no camping involved:


Here's a good shot of the bike folded on the train, with the P-clamps clearly visible. Those are Jandd stays, wider, I later went to Topeak(IIRC?) which are narrower but thicker:

Have you been spying on my AliExpress wish list recently?

I had come to a similar conclusion, but haven’t pulled the trigger yet. I was toying with both sets of TQIQT racks for an orange and black monster, and building it up with my standard Microshift Advent setup with dropped bars. Good to know about the pignose issue, what’s the measurement between the bolt centres?

I do not think that the pignose spacing is an "issue": its most probably made to mount a Brompton front block because they copied Bike Friday and Bike Friday has an optional Brompton block mounting on several of their frames.

I and my friends have a couple of Trail Blaze builds.
It has a standard BSA 68mm BB and a 142 thru axle rear O.L.D., so when using wide tire (>2.0), the chain may interfere with it. One of solutions is to consider a wider crank.
And regarding the cassette, I don't think 50t will fit, because you can only use short or middle cage RD.

That's sharp! I love slate blues. Bonus points for the Thudbuster post!

Even a cheap Tourney GS (mid) length cage provides 43T capacity, which would handle 11-50, however the slope the parallel linkage moves on is not steep enough for above 34-36T low. Ron's video shows it works with his chosen RD, as long as you are OK with the cage extending below the rim in the middle gears, meaning if the tire flats at that time, the cage is gonna drag on the ground.

EDIT: I have one question about this frame design (and Bike Friday), and I'm gonna post a pic of my bike to help clarify.

The handlepost extends straight up on the steer tube axis, then is capped with a horizontal stem. On my bike, the handlepost is canted forward, to extend directly to the handlebars. The comparative steering geometry is similar. My question is, with the handlepost coming straight up for a horizontal stem, is there any knee striking when climbing standing? My bike with the forward canted post, plenty of clearance, when I put a small, thin handlebar bag on the back of the handlebars, I was hitting it with my knees when standing climbing. Again, for comparison, my bike:



I LIKE the idea of a horizontal stem on top, it allows the option of a suspension stem. But clearance there is critical, I rock the bike laterally when I climb.

Of course, it will fit. Did you not see the video and image I posted that shows a medium-cage RD with a 11-50T cogset?

SGD? Aliexpress does it in NZD but i guess over 750 SGD

Thanks DG - will try the racks i have on hand - who knows, one might work

I wonder how much GTA paid for his in the PRC.

Ha! Yes we seem to be thinking similarly. Hopefully Trail Blaze will work out well - if it goes well on longer trails Keri will be wanting one too.
i didn' notice an orange and black one on Aliexpress?
As Jipe says, the pig nose is probably brompton style - i will measure the distance between centres next week when i get the chance

Your bike looks great GTA and thanks for the wider crank suggestion. Was thinking about thudbuster or similar but might go for a dropper post instead as they help with my dodgy balance

In mainland China it is 3500CNY.

TQIQT is developing another folding bike model. It has a similar folding mechanism as the Trail Blaze.
Triple butted CrMo frame, 451 wheels, 44mm headset, carbon fork.
Significantly lighter.

I have a spy photo but it was an early prototype:

About a $80 mark-up in SG, then.

Interesting mix of TIG welding, brazed lug, and brazed diagonals, the latter indicating more BF NWT (probably Pocket Rocket with the 451 wheels) than Diamond Llama or All-Packa like the Trail Blaze.

BF currently powder coats, which can be thick and tough, but often thin at sharp edges, and nothing inside. It would be a plus if TQIQT phosphates, then does a dip paint and bake, probably would be spray due to varying colors, but an electro-deposition spray and bake will still be a tough paint, just no paint on the inside. Consumers doing a buildup can spray in various oils or coatings to protect the inside. Phosphate and a good baked enamel would have well over 1000+ hours salt spray, cyclic corrosion (wet/dry/wet etc.), and stone chip (gravelometer) resistance.

I seriously considered all these factors when buying my first folder but I felt my head was going to explode so I just bought a cheap Zizzo.

I'm just glad we didn't hear about the 2x conversion, the Deltec cable hack, the seat tube crack and plastic bushing design flaw, or the super-rigid Cannondale Road bike for the umpteenth time.