Many thanks for the great support to Wiktor, David and Paul!
Freshly made by using lots of tools and pleasure, spiced with custom wheels, new reinforced rear hinge bolt kit and served steaming hot by gourmets
At shown Strida are the achieved gear ratios, due to the bigger circumference of the 40-349 Greenspeed Scorcher tyres (UK/EU source), a few percent higher than that of original 18“ tyres – approximately
in low gear 3,6m
in middle gear 5,1m
and in high gear 6,4m.
I take it this is custom made - as a hobby? It is not a mainstream model we can buy? This can be slapped into a 1 speed EVO (only - per our chat) – what are the costs and who can do this? I don’t think my local bike shop can do this - Strida’s are kinda unique not the regular bike… despite my local bike shop is a Strida Reseller (I don’t think they will…). Basically is this for show to us that it can or we can expect some special models to be on “sale”.
Lastly -in my quest for Strida speed - so this gear ratio makes it faster than a stock Strida 18" EVO?
In this case yes, but in close cooperation with efneo.
Not right now – first we need to convince David from Taiwan to make more beltwheels for us.
(We need a special BCD for the efneo - common 80 t beltwheels are not suitable.)
Made to retrofit into all single (or dual) speed bottom brackets.
(Maybe in future also to replace the KS3 for EVO.)
Sorry, no clue about the costs (so far, even the shown drive wasn’t paid to its seller )
Once there is a complete kit available it won’t be a question of „who can“ – the question is much more „who has all the tools“.
Principially you can refer to the Schlumpf installation thread, the efneo kit installation would be pretty equal (Except the torque lever positioning and the shifting cable routing for the efneo).
Sorry, at the moment I’m unable to supply serious data about the weight.
Shown Strida bikes are pretty similar but not equal, both are equipped with custom wheels of unknown weight.
According to a cheap digital luggage scale is the EVO (13,4 kg) ~ 1 kg heavier than the efneo Strida (12,4 kg).
(Accurate data will follow.)
Hi Willie - you’re right, they are really huge - which is very odd because they’re 16" tyres.
Just the previous rims were not adequate for this special one, had to make better wheels immediately
Here are a few more, together with the new Strozzapreti 355-25 tyre;
Scorcher 349 tyres pressure range is 40 - 100PSI (2,8 - 7 bar)
Max. load 80 kg
According to Wiktor (efneo crew member), the efneo drive was sold to UK, so that is correct.
Interesting find that store…
So, we Strida fans could possibly source a drive - but we would need also a matching 80 teeth beltwheel. As far as I remember, the common ATS beltwheel does not fit the efneo GTRO.
The ATS excenter does fit, but there’s an additional thread required
I’d like to add some info about the blue Strida above.
Since last year it is not any longer mine, it was sold to my dear friend Christoph (Netherlands).
When we met last summer in Friedrichshafen I had the bike with me and he fell totally in love with it. Well, he wanted it so badly that I had to give it to him
The farewell wasn’t really tragic - because I knew that there’s one more efneo kit waiting at my private stock
So, right now, I’m converting a black SX into another efneo Strida
If the brand? patent? was sold to the UK company, it must be true!
Or it would be great if they sell a set for the STRiDA.
Either way, I hope it would be good news for STRiDA fans who need a multi-speed…
That’s right…
There is a cheap belt drive set with 130mm BCD belt wheel like this on AliExpress, but it seems to be 95T, so the gear ratio will be completely different…
This may be information already available, but as mentioned in this tweet (in Japanese), it looks like the eccentric BB can be made with a generic part(Tange 68mm-127.5mm.).
P.S.:
That image of the Japanese blog looks exactly like a modded ATS excenter with the bottom bracket (bearings) of an efneo drive.
Here next to a disassembled single speed excenter:
Thank you for the detailed explanation with pictures.
The ATS excenter can be purchased on e-Bay (although I don’t know what kind of processing is required), and the BB seems like it should be possible to use a generic product, so that problem should be solved.(I feel like the width of the excenter is quite different, so I have some doubts about the centering of the belt.)
If we believe the website of the supplier mentioned earlier, it seems that GTRO uses a universal BCD of 130mm to be compatible with multiple models, but it seems difficult to obtain a BCD of 130, preferably an 80T HTD belt wheel.
It may be possible to use the ATS one if it is modified, but the labor hours and precision required for strength processing are likely to be significant issues.
While searching for such a belt wheel, I came across a standard called CDX(This link has an English PDF explanation), but it has an 11mm pitch and a guide rib in the center, so it would be difficult to use without completely replacing the belt system.
That’s only if the rear freewheel (ISO thread standard) is compatible with the STRiDA as is…
In that case, the gears are a maximum of 70T on the front and fixed at 22T on the rear.
There is also an 8mm pitch CDX Tandem that would seem like it could be used with the rear as is, but it has only one type of belt, so it would be difficult to make it compatible with the STRiDA.
In any case, it may be difficult to put this experiment into practice because the yen is currently weak and the price of ÂŁ440 would be enough to buy another one or two STRiDA 5.0 or LT in Japan.
I overlooked this article! The rear freehub seems to be fine.
Calculating the reduction ratio, for my purposes since I live on a hill, I want the ability to easily climb slopes of about 7% gradient rather than top speed, so a combination of fairly low first gear and second gear with a ratio close to the current 3.33, Would a 48T or 50T belt wheel be best…?
As shown above; there is one left and one right hand BSA thread required, nothing else.
Caution, do not overlook another limit - the size!
If you want to use a beltwheel which is smaller than, maybe 72 or 74 teeth, the belt had to run through the bottom tube!
Oh no… you’re right, the bottom tube of the STRiDA doesn’t pass through the center of the belt line.
I haven’t calculated the exact dimensions, but that means that a CDX system with a belt wheel up to 70T can’t be installed unless I attach a sub-pulley like the ones found on car engine pulleys…
It looks like someone has installed Carbondrive CDX on a STRiDA.
It looks like a 74T front belt ring and a 128T belt (He speculates that a 130T would be a better fit).
By the way, what is the diameter of the Speeddrive or Efneo 80T belt ring?
I estimate that it has 80 teeth with an 8mm pitch, so the circumference is 640mm, and dividing that by pi gives me about 204mm.
If I do the same calculations, the Carbondrive CDX 55T is estimated to have a pitch of 11 mm, an outer circumference of 605 mm, and a diameter of approximately 193 mm, so it may just be possible to fit it into the STRiDA.
For now it’s just armchair theory…
)
