So I took my bike (MTB) to the trails!

[IgnitionGundam]

Also interested ..waiting for the group buy! DO IT.

[bestwheelbase]

@the Red Devil thanks for sharing your progress. One question, could the bike position be moved slightly so it's not blocking taillight visibility? I would buy something like this.

[YW-Slayer]

I'd also be interested in buying this. Forgive the n00b question, but how easy is it to remove and re-install those plates (which allow the "rack"/holder's arms to be installed)?

[supramkivtt2jz]

Originally Posted by anthros

While I understand your concern, there is no problem using a longitudinal mount in this lateral orientation. A bike mounted as the OP has done wouldn't experience unusually high stresses in the fork or any other area; no reinforcement is necessary. Remember, bicycle forks are designed for bombing down mountain passes whether on or off road. With no rider aboard, any stresses from acceleration, braking or vibration will be much lower than they would be on even a moderate ride.

To the OP: I really, really like this design, especially because you can easily remove the rack and store the bits in the trunk. If you have a chance to post some drawings, I'd really appreciate it.

I plan on buying a BRZ in the next year or two. I can easily make my own rack, but I'd love to have a rough idea of what you did as a starting point. This is a very clean design, and it makes me even more excited about owning a BRZ than I was before.


Cheers,

Jason

P.S. For what it's worth, I'm a mechanical engineer who has raced bicycles for the last 25 years.

Im an engineer myself, and it is why I have my concerns. With a bike in operational condition, any force exerted on the wheels acts as a point load between the fork arms. With this setup, each arm experiences a different load.

I agree its a nice solution, but If I went this route, I would use the Frontloader for a little peace of mind.


I have a solution being cnc'd as we speak. Ill post up pictures when it is done. I plan on releasing the plans for free

[anthros]

Originally Posted by supramkivtt2jz

Im an engineer myself, and it is why I have my concerns. With a bike in operational condition, any force exerted on the wheels acts as a point load between the fork arms. With this setup, each arm experiences a different load.

I have to admit that I'm not quite sure what you mean by "point load" in this context. Perhaps you're referring to the vertical load from the tire's contact patch. If so, I see why you're calling it a point load.

But if that's what you mean, you are grossly underestimating the out-of-plane loads (the plane of the frame and wheels) that bicycles regularly experience. Mountain bikes especially deal with large out-of-plane forces as the front wheel makes oblique contact with obstacles, e.g., brushing one side of the tire against a large rock on a descent.

I'm also confused by your objection that "each arm experiences a different load." Actually, it's the same load, just with a different sign. In engineering terms, it's just a couple that produces a moment. In any case, the load is very small compared to the dynamic loads the fork sees during a ride.

I gather you might be somewhat new to cycling (you called it a "fork arm," not a fork leg) in which case your concern makes more sense. But when you think about it, the loads on a bike on a rooftop carrier are similar. There are all sorts of roll inputs to the car on uneven surfaces, and the forcing frequencies tend to be close to the natural frequency of the bike atop the rack. Rooftop-mounted bikes experience plenty of moment that gets reacted out through the front dropouts. IMHO, this arrangement is no worse and may actually be better.

Originally Posted by supramkivtt2jz

I have a solution being cnc'd as we speak. Ill post up pictures when it is done. I plan on releasing the plans for free

Cool! I'll be interested to see what you came up with...you may well have considered lots of things I haven't. I look forward to seeing your drawings.

Cheers,

Jason

[aCab]

Ill send you money right now if I can get one of these! How's the progress looking?

[shadowlady1997]

I am getting really desperate for a bike rack solution for my car. I just sold my second vehicle so my BRZ is my only mode of transporting both my road and mountain bike. Has there been any progress on any of the inventive ideas you've shared here?

[Ozzman]

Originally Posted by shadowlady1997

I am getting really desperate for a bike rack solution for my car. I just sold my second vehicle so my BRZ is my only mode of transporting both my road and mountain bike. Has there been any progress on any of the inventive ideas you've shared here?

I don't have any pics, but you can get some standard Yakima crossbars and have some 16x1.5 bolts of the appropriate length welded to the crossbars.

Then use some spacer cut to length that will bottom out on the tow hook threads before the bolt head bottoms out on the bumper beam. I made a spacer out of lengths of tubing cut from an old bent MTB handlebar.

Now you just need to mount your favorite bike tray to the crossbars.

[anthros]

If someone with a caliper can measure a few dimensions, I'd be happy to draw something up in Solidworks. Ozzman just gave me the thread size. I'd need a photo of the uncovered tow hook area and the distance from the face of the tow hook area to the bumper surface.

I would also need the diameter of the engageable area around the tow hook threads to avoid the spacer issue that Ozzman mentions. Any takers?

[Ozzman]

Originally Posted by anthros

If someone with a caliper can measure a few dimensions, I'd be happy to draw something up in Solidworks. Ozzman just gave me the thread size. I'd need a photo of the uncovered tow hook area and the distance from the face of the tow hook area to the bumper surface.

I would also need the diameter of the engageable area around the tow hook threads to avoid the spacer issue that Ozzman mentions. Any takers?

Just get your tow hook out and thread it in and mark with a sharpie where it exits the bumper beam, From that mark to the end of the threads on the towhook is how long the bolt needs to be from the head to the end of the threads.

The 45degree angled shoulder on the towhook is where it bottoms out on the threaded insert, so your spacer needs to be the same length as the distance from the sharpie mark to the middle of the 45degree shoulder.

[anthros]

My tow hook? What tow hook? I don't own an FT-86 of any variety. That's why I'm asking for measurements. That 45-degree bevel is a great thing to know about...that's why I was asking for a photo.

I'm looking forward to buying a BRZ, most likely the 2015 model year (if engine output goes up...otherwise, I'll be happy with whatever year). Weirdly, I recognize Ryephile from the MINI forums back in '05-'07 or so.

Cheers,

Jason

[Ozzman]

Relevant towhook dimensions.

Thread size: 16x1.5
Thread length: 28mm
length from thread tip to exit of bumper beam: 135mm
length of shank between threads and start of shoulder: 16.2mm
thread tip to start of angled shoulder: 44.5mm
thread tip to end of angled shoulder: 50.5mm
distance from thread tip to where threaded insert contacts shoulder:46.9mm
The angle of the shoulder seems closer to 25-30 degrees, than 45 degrees.
Distance from end of shoulder to exit of bumper beam: 84mm
Measured thread diameter: 15.85mm
diameter of shank between shoulder and threads:16.33mm
Diameter of towhook after shoulder 20.25mm I used a 22.4mm dia spacer and there is still 1-2mm to spare in the entry hole to the bumper beam.

[2000GT]

Very interested in this idea. I am an almost daily biker, but since I bought the FR-S, that's declined. Using a Saris tail rack for now. A do able solution, but I am open to a more permanent and simple, clean solution, like this. Solid and no real touching the car.
Looking forward to some more details.

[jabingb]

Here's what I cooked up for my FR-S. Sadly the car was bought back by Toyota so I really didn't have a chance to use it but plan on getting a '14, hope the tow hook aperture spacing doesn't change. Should be able to carry 2 bikes comfortably.