Roof rack question

[scblack]

Guys, I have bought four simple bike racks for my car and camper. The ute attachment style ones that just have a quick release attachment to the fork and the wheels are stored in the car or camper.

My Forester roof racks are an easy fit, they have the channel for bolts to easily fit. These:




My question is upon fitting the same little rack to my camper roof racks. On the car, the quick release sits upright, the fork slots down, I tighten the cam and bike is secure. Unfortunately the beams across my camper are not flat like these racks. The camper roof rack beam is a rounded oblong shape with the oblong being upright. I will just drill through the roof beam and bolt the base of the rack on the side. However if I do it this way, the fork is not sitting directly down onto the quick release. Is this an issue at all? I think it should be perfectly fine as the fork will sit down onto the bolt and I will of course tighten up the quick release securely. But the angle of the little rack means the fork is not sitting down onto it.

Here's some pics of me sitting the rack on the camper roof beam.

 

[Calvin27]

Not sure if I am reading this right, but my take is you should just press the fork all the way into the QR. This means your bike is not completely vertical but kind of leaning over a little bit. Not a big deal for the bike as it leans a lot more during turning etc. I'd be more concerned with the qr only attached properly on one fork leg! The rear wheel I assume will be strap on - it doesn't matter if it's leaning a bit.

I have seasucker Talon (suction cup) and the side of my car is not flat so when the bike goes on, it's not perfectly upright either. As long as the fork is securely all the way into the QR it holds up fine.

 

[scblack]

Not sure if I am reading this right, but my take is you should just press the fork all the way into the QR. This means your bike is not completely vertical but kind of leaning over a little bit. Not a big deal for the bike as it leans a lot more during turning etc. I'd be more concerned with the qr only attached properly on one fork leg! The rear wheel I assume will be strap on - it doesn't matter if it's leaning a bit.

I have seasucker Talon (suction cup) and the side of my car is not flat so when the bike goes on, it's not perfectly upright either. As long as the fork is securely all the way into the QR it holds up fine.

Not quite sure what you mean about being at an angle on my camper roof? Both sides of the fork will be properly secured in the quick release. Bike will be perfectly vertical. Rear wheel will just be strapped to a roof beam (with a little drill hole so wheel can't move side to side).

As you say, as long as the fork is properly inserted and secured tightly in the quick release I think I should have no problem.

 

[Calvin27]

However if I do it this way, the fork is not sitting directly down onto the quick release. Is this an issue at all? I think it should be perfectly fine as the fork will sit down onto the bolt and I will of course tighten up the quick release securely. But the angle of the little rack means the fork is not sitting down onto it.

I don't get what you mean by this.

 

[scblack]

I don't get what you mean by this.

The bike rack is an "L" shape with the quick release on the top of the longest side of the "L". On the car roof racks, the quick release is on top of the whole thing, and the fork sits down on the top, pressing any weight straight down through the roof rack.

Because the camper roof rack is not flat on top, I have to put the bike rack at the side, and the top of the "L" with the quick release is sticking out at 90degrees on the side. Thus the weight of the bike is not pressing straight down into the roof rack through the bike rack.

I'm not sure how to explain easier.

 

[MARKL]

I wouldn't worry about it... now, what size is your SlopeStyle and when will you be taking it for a drive on the camper?

 

[wilso1]

To summarize, you're asking is whether the different orientation of the mounting bracket is less secure? Whereas the load/weight in the old set up was working on a vertical plane and supported by the roof rack, in the new set up there is no bulk under the bracket?
I think you'd be fine.
- The bolts between the rail and the bracket are unlikely to fail - you can over-engineer that as much as you want.
- The QR bracket will no longer be unsupported. Under your old set up, the forces from wind resistance when travelling at speed would have been pulling at that bracket, opening the L shape if you will. In your new setup, the forces (at rest) will be acting in the same direction. So if the bracket hasn't failed yet, I don't see why it would fail in your new setup.

That's my 2 cents worth.
(insert standard 2 page disclaimer here)

 

[Calvin27]

The bike rack is an "L" shape with the quick release on the top of the longest side of the "L". On the car roof racks, the quick release is on top of the whole thing, and the fork sits down on the top, pressing any weight straight down through the roof rack.

Because the camper roof rack is not flat on top, I have to put the bike rack at the side, and the top of the "L" with the quick release is sticking out at 90degrees on the side. Thus the weight of the bike is not pressing straight down into the roof rack through the bike rack.

I'm not sure how to explain easier.

ok I think I get it. You are concerned with not the QR, but the bending force on the L plate and the two bolts that attach it to the roof rack.

I think it will be fine. I have what looks like the exact same plate and QR and the M6 bolts should be strong enough. If you are really concerned get a thicker nut and maybe some washers.

FYI I run a thru axle adaptor on the exact same mount on top of the qr. This makes the fork overhang by about 100mm. It's hasn't give me problems yet.

 

[scblack]

To summarize, you're asking is whether the different orientation of the mounting bracket is less secure? Whereas the load/weight in the old set up was working on a vertical plane and supported by the roof rack, in the new set up there is no bulk under the bracket?

ok I think I get it. You are concerned with not the QR, but the bending force on the L plate and the two bolts that attach it to the roof rack.

I think it will be fine. I have what looks like the exact same plate and QR and the M6 bolts should be strong enough. If you are really concerned get a thicker nut and maybe some washers.

Yup, I think we have got there. Its not the easiest query to put in words. I will be using a backing plate on the other side of the camper roof rack to pass the bolts through and washers of course.

I agree with you guys and think it will be plenty secure. Cheers guys.

 

[redbruce]

The bike rack is an "L" shape with the quick release on the top of the longest side of the "L". On the car roof racks, the quick release is on top of the whole thing, and the fork sits down on the top, pressing any weight straight down through the roof rack.

Because the camper roof rack is not flat on top, I have to put the bike rack at the side, and the top of the "L" with the quick release is sticking out at 90degrees on the side. Thus the weight of the bike is not pressing straight down into the roof rack through the bike rack.

I'm not sure how to explain easier.

It will be fine.

Weight (and therefore force) on the fitting is low and will apply a small bending moment to the QR bracket. I assume the beam it is mounted to will be sturdy enough to cope given its designed load limit.

 

[scblack]

It will be fine.

Weight (and therefore force) on the fitting is low and will apply a small bending moment to the QR bracket. I assume the beam it is mounted to will be sturdy enough to cope given its designed load limit.

The roof racks on the camper have a load limit of 100kg, so should be plenty of load limit.

 

[99_FGT]

You could always drill the "longest side of the L" and mount it upright, but unless you are carrying a very heavy bike it won't be an issue - as Wilso said the forces from wind, turning, bumps etc are much greater than the 70-100N for a static bike.

 

[scblack]

Ok, I got them in place.

Note: That is not my bike, it is the shitter hanging around in the warehouse.

 

[stirk]

Ok, I got them in place.

Note: That is not my bike, it is the shitter hanging around in the warehouse.

Sure mate we believe you.

 

[hifiandmtb]

Those two screws look strong.