e750d OS Groadster


Well-Known Member
Pieced together a TSDZ2 running OS software on an OS Blackbuck hardtail.

48v/18Ah/21700 cell HL type battery

Advent 9spd drivetrain 11/42

Hayes Trail brakes

750d/40c Nanoraptors/Handbuilt wheels with generic hubs and 311mm spokes...

WTB headset and saddle

Ti post I had kicking around....thought I had a bar/stem in stock but ended up having to do a trip to the big city to get one at a friends shop and as luck would have it it actually is the right combo...

25 zip ties, assorted colors

Installation time included building the wheels and from frame up. I started assembling parts from all over 3 weeks ago and took it out for a shakedown cruise today.


Initial impression is that this is a fast bike and likes pavé and gravel just fine which is what I wanted for where I am living. The chainline is as usual out too far for the lower gears but I have a fix for that using an offset chainring like I did on my TSDZ2 eMTB. I don't have a scale so I don't know what it weighs other than it is alot lighter without the battery on. But riding it is not affected at all and even though it is a rigid bike it is pretty comfortable.

I ran 33psi with tubes off the stand and didn't feel like they needed to be any more or less. I taped the rims and will be converting to tubeless for the security I have become used to and I feel a more supple ride quality.

Needs a few tweaks here and there and then more testing needed which is the good part.
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That is a truly beautiful bicycle, congrats on your build! When I saw it over on the Ride1Up forum I thought maybe it was an old Breezer 29er, but at least I was right about the 29er part. Seeing that rear tire just barely sneak under the seat stay bridge really puts those wheels in perspective!


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Seeing that rear tire just barely sneak under the seat stay bridge really puts those wheels in perspective!

That it does and while I doubt I would ever actually run these wheel combinations on this bike as I was converting to tubeless today I messed around fitting my spare wheels on the bike, just because I have too much time on my hands......

Top pic is 700c/i35/2.3 front and 650b/i45/2.5 rear

Bottom is same front with the same size wheel in the rear

Both combo's fit comfortably with the 2.3 rear wheel showing about the same amount of clearance at the seatstay bridge, These are combo's I have run in the past on my mtb but I have been using a similar arrangement for the last couple of years as the top pic. Except with a 2.8 tire on an i35 rim/650b rim.


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Nice! Those both look like a more natural fit, especially in the front. I'm sure the larger volume tires make for a smoother ride. I'm a fan of steel myself and those seat stays look designed to provide some extra give in the rear.


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The bike was not designed with the narrower tires in mind for sure. They look more in proportion on the frame/fork designed for them like this front hub drive build utilizing the same wheels I am trying to get finished...


But still I am not looking for mtb performance from either of these builds. I have a tool for that in the shed.

Wow, you've got an impressive fleet! I've never seen a fork like that before, is it something you made yourself? Also, is that a rear shock in the middle of the linkage?


Active Member
"Proflex" fork?
Do you perceive a softer (?) Maybe through your wrists.
Is there damping action of the extra linkages moving ?
Maybe initial force vectors first upward and forward (Link Removed - Attachment No Longer Exists)away from the handlebars.
I thought of the older linkage forks too, but this one is at least new enough to have a disc brake. Also, it puts the front wheel way out there. The effective ht angle must make it handle a bit like a dh bike.


Well-Known Member
That is a Fournales fork that was made in France and marketed here in the states by LOOK in the late 90's. Originally a 26" wheel fork the dropouts were removed and replaced with ones that are 35mm longer to fit 29" wheels by a friend in Michigan 15 years ago. There is a pivot point on the bottom of the headset that can be run either rear or forward facing. The forward facing as shown provides for way more rake which is more in line with modern geometry. It does sacrifice a little on tight turns but works much better climbing and descending. Set the other way, which was the stock setting, with less rake the steering was too twitchy I found.

The shock is just a simple piston type and does look like a rear one. I have been riding these forks on this bike for years now and for my personal style of riding I haven't felt the need to change.

steve marino

Active Member
That front fork design has been used for eons on motorcycles. If they're built correctly and maintained properly, they are a perfect addition to any bike. Engineering wise, they make more sense than a standard sprung fork because the forces are spread out in several directions vs just up and down w/ a tube front fork. This type of fork is more expensive to make and needs good materials, more machining and tighter tolerances than a conventional sprung fork, which is why they're seldom seen on a production bike.