Speed restriction re Roof Racks.

plowmar

For first time am taking bikes with me on holiday. Only thing that concerns me is, is there a recommended maximum speed I should adhere to with two bikes on the roof?.

Bike sites don't seem to cover this part other than how strong their roof racks are.

cooldad

The speed limit.

Man Of Lard

The speed limit, or any lower limit imposed by the manufacturer.

plowmar

Thanks guys, but as I indicated the makers don't give any indication, and obviously I wouldn't be breaking the speed limit.

andcp

Don't know what you're buying, but for the Freeride (their cheapest option) Thule state a max speed of 130 km/h (80 mph).

davesnothere

I've done well over 100mph with mountain bikes on Thule ProRide on top of my old Subaru Outback without a problem coming back from the continent

darkhairedlord

If its a carbon road bike I would not be putting it on the roof.

Bobbinogs

darkhairedlord wrote:

If its a carbon road bike I would not be putting it on the roof.

Any reason why not? I know some manufacturers specifically advise not to use their bikes on a turbo but I haven't seen anything that rules out roof racks, or did I miss [ironic] [/ironic]??

craigus89

Because if it rains they'll melt, obviously.

It's fine, just be sensible about how you attach them to the roof.

roubaixmb

Thule say 80mph.

darkhairedlord

Bobbinogs wrote:

darkhairedlord wrote:

If its a carbon road bike I would not be putting it on the roof.

Any reason why not? I know some manufacturers specifically advise not to use their bikes on a turbo but I haven't seen anything that rules out roof racks, or did I miss [ironic] [/ironic]??

Specifically, the method of attachment. Where they clamp around the frame with an arm. Carbon bikes (or any light-weight engineered structure) are designed to carry the forces in use with wall thickness reduced where loading is reduced. They simply aren't designed to be clamped around the frame or receive side loading on the down-tube or seat-tube.
And they'll melt if it rains.

plowmar

Thanks question answered. Bought rack via Audi who have Thule make them.

Bobbinogs

darkhairedlord wrote:

Bobbinogs wrote:

darkhairedlord wrote:

If its a carbon road bike I would not be putting it on the roof.

Any reason why not? I know some manufacturers specifically advise not to use their bikes on a turbo but I haven't seen anything that rules out roof racks, or did I miss [ironic] [/ironic]??

Specifically, the method of attachment. Where they clamp around the frame with an arm. Carbon bikes (or any light-weight engineered structure) are designed to carry the forces in use with wall thickness reduced where loading is reduced. They simply aren't designed to be clamped around the frame or receive side loading on the down-tube or seat-tube.
And they'll melt if it rains.

yeah, makes sense, well most of it ;-)

I guess the thule outride (fork and back wheel clamp) would be the safest then??

johnmiosh

I was advised that the best way was to wrap a pad around the down tube to spread the load and provide friction so it would not need to be so tightly clamped. The first time I tried it on a carbon frame, I could see the tube being squashed. I stopped and got one of these instead.

http://www.elite-it.com/en/products/gb/ ... -tour-lock

Should be able to get one for about thirty quid. A matching wheel carrier is also available, but that adds another thirty quid on top.

slowbike

darkhairedlord wrote:

Bobbinogs wrote:

darkhairedlord wrote:

If its a carbon road bike I would not be putting it on the roof.

Any reason why not? I know some manufacturers specifically advise not to use their bikes on a turbo but I haven't seen anything that rules out roof racks, or did I miss [ironic] [/ironic]??

Specifically, the method of attachment. Where they clamp around the frame with an arm. Carbon bikes (or any light-weight engineered structure) are designed to carry the forces in use with wall thickness reduced where loading is reduced. They simply aren't designed to be clamped around the frame or receive side loading on the down-tube or seat-tube.
And they'll melt if it rains.

I wouldn't think the loading at the clamp point is going to produce massive force - the wheels/fork are clamped to the rack and the arm is to keep the bike upright - it's a reasonable size clamp so no point loading and side to side forces are minimal - it's not an F1 car ... !

fat daddy

Slowbike wrote:

I wouldn't think the loading at the clamp point is going to produce massive !

never underestimate the ham fistedness of people.

you can happily and safely secure a carbon frame with a roof mount, BUT, and the manufacturers know this, there is nothing to stop you from keep on turning that screw until you dent and splinter the crap out of your frame, and then decide its Thule that's at fault and try claiming for your frame.

slowbike

fat daddy wrote:

Slowbike wrote:

I wouldn't think the loading at the clamp point is going to produce massive !

never underestimate the ham fistedness of people.

you can happily and safely secure a carbon frame with a roof mount, BUT, and the manufacturers know this, there is nothing to stop you from keep on turning that screw until you dent and splinter the crap out of your frame, and then decide its Thule that's at fault and try claiming for your frame.

Hmmm - I use a bike stand with quick release clamp on the top tube of my bikes - including carbon one - I'd have to be pretty ham fisted to over tighten it to the point of damage .. but yes - I get your point - there are some people out there with carbon frames who are denser than their frames!

Monty Dog

BUT, and the manufacturers know this, there is nothing to stop you from keep on turning that screw until you dent and splinter the crap out of your frame, and then decide its Thule that's at fault and try claiming for your frame.

Which is why roofrack manufacturers put a huge disclaimer on there to absolve themselves from claims when someone ham-fistedly crunches their frame in a clamp. I'd be far more worried about height restrictions, low-hanging trees than speed.

imposter2.0

darkhairedlord wrote:

Bobbinogs wrote:

darkhairedlord wrote:

If its a carbon road bike I would not be putting it on the roof.

Any reason why not? I know some manufacturers specifically advise not to use their bikes on a turbo but I haven't seen anything that rules out roof racks, or did I miss [ironic] [/ironic]??

Specifically, the method of attachment. Where they clamp around the frame with an arm. Carbon bikes (or any light-weight engineered structure) are designed to carry the forces in use with wall thickness reduced where loading is reduced. They simply aren't designed to be clamped around the frame or receive side loading on the down-tube or seat-tube.
And they'll melt if it rains.

darkhairedlord

Imposter wrote:

darkhairedlord wrote:

Bobbinogs wrote:

darkhairedlord wrote:

If its a carbon road bike I would not be putting it on the roof.

Any reason why not? I know some manufacturers specifically advise not to use their bikes on a turbo but I haven't seen anything that rules out roof racks, or did I miss [ironic] [/ironic]??

Specifically, the method of attachment. Where they clamp around the frame with an arm. Carbon bikes (or any light-weight engineered structure) are designed to carry the forces in use with wall thickness reduced where loading is reduced. They simply aren't designed to be clamped around the frame or receive side loading on the down-tube or seat-tube.
And they'll melt if it rains.

They get free bikes. It's not raining. They only go 30mph.

proto

Thule Outride, two very expensive carbon bikes, over 100mph at times, and for hours at 80mph (Rome and Back, and Lorient and back). No issues at all apart from dead flies all over the front of the bikes.

PS I'd be very wary of the roof mount that clamps on the down tube. I've seen some terrifying instances of bikes 'fluttering', shaking themselves violently mounted on car roofs at motorway speed.

scopes15

I have damaged a carbon frame on a roof rack before - I think it might have been a cheaper halfords bike carrier that clamps the downtube. Not sure if the clamp was overtightened or that the bike was left on the carrier overnight with the wind battering it that caused the damage.

proto

Bloke turned up today at work with one of these, Yakima Front Loader. Very impressive. Bike rock solid and no carbon/clamp interface.

davesnothere

proto wrote:

Bloke turned up today at work with one of these, Yakima Front Loader. Very impressive. Bike rock solid and no carbon/clamp interface.

Looks a good solution, presume there is adjustment for narrower road wheels?

bobmcstuff

If you get an aero road bike, will it improve your fuel consumption when it's on the roof rack?

joncomelately

bobmcstuff wrote:

If you get an aero road bike, will it improve your fuel consumption when it's on the roof rack?

No, but it might decrease drag above the car sufficiently to create lift, thereby giving you a flying car...

micrographia

Newest Thule ProRide has thick soft jaws on the down tube clamp. Only carbon you'd need to worry about damaging is if you have deep section wheels. If travelling at motorway speeds in the rain it's worth securing something around your headset to help stop water getting in though.

ben@31

RoubaixMB wrote:

Thule say 80mph.

Same with the Saris Bones bike rack.

However I'm more p!ssed that the bike rack feet definitely damaged the paintwork on my car that any potential damage it could cause to the bike frame.

js14

proto wrote:

Thule Outride, two very expensive carbon bikes, over 100mph at times, and for hours at 80mph (Rome and Back, and Lorient and back). No issues at all apart from dead flies all over the front of the bikes.

The Thule website says that the Outride isn't suitable for carbon frame bikes, but maybe they are being over cautious. Instead they say to use the Sprint XT, which is obviously a lot more expensive! Has anyone got any experience of the (revised, post-recall) Sprint XT bike carrier? Thules' support page also recommends several other of their products for bikes with carbon frames : https://support.thule.com/hc/en-gb/articles/214350465-Can-I-mount-a-carbon-bike-on-a-Thule-bike-rack-

mr_mojo

I've just bought a Thule Sprint XT but not used it yet so can't comment. I'll be using it on a Colnago C60 so hopefully it'll be ok!

proto

JS14 wrote:

proto wrote:

Thule Outride, two very expensive carbon bikes, over 100mph at times, and for hours at 80mph (Rome and Back, and Lorient and back). No issues at all apart from dead flies all over the front of the bikes.

The Thule website says that the Outride isn't suitable for carbon frame bikes, but maybe they are being over cautious. Instead they say to use the Sprint XT, which is obviously a lot more expensive! Has anyone got any experience of the (revised, post-recall) Sprint XT bike carrier? Thules' support page also recommends several other of their products for bikes with carbon frames : https://support.thule.com/hc/en-gb/articles/214350465-Can-I-mount-a-carbon-bike-on-a-Thule-bike-rack-

Sprint XT didn't exist when I bought my Outride. As a professional engineer, with a lifetime of experience (I'm 64), I cannot see any reason why they should exclude carbon frames. Complete nonsense.

BTW bikes on roof C59 and Edmonda SLR, each alone worth more than the car (SAAB 9-5 estate)