Burley flatbed lost a wheel at 33mph.
#1
Thread Starter
Senior Member
Joined: Aug 2007
Posts: 487
Likes: 0
From: Chi-town
Bikes: Fixie conversion, a few 10 speeds, a trailer, I GT Transeo for utilitarian riding
Hey everyone,
I was at my place in Michigan this weekend. I am currently building up a fixie out of a 1986 Varsity frame. Its a lightweight lugged frame with aluminum bullhorns. so it weighs like 10 pounds or so. I was towing this on my burley flatbed behind my 1968 Schwinn Varsity. When I reassembled the trailer, I apparently didn'y tighten the wheels up enough, and the left skewer shook itself loose. SO I get to a point on a 25mph road where the road goes down into a river valley. It is downhill for about 1/3 of a mile (steep). I got the rig up to 33 mph when I started to feel the trailer bounce around alot, since the load weighed less than the trailer itself. Then I the trailer hit a bump, go up in the air,and then I heard dragging. I thought I flipped the trailer, that would have been a first. I braked quickly, then a 20" wheel with an offset hub, went flying downhill past me. I watched as it rolled downhill and then I pushed my riginto the grass next to the road. Some people pulled up in a Mercedes and gave me a ride half way down the hill to where the wheel rolled into some brush. I walked back uphill and reattached the wheel. I made the dropout was okay, and that both wheels were on extra tight and i continued downhill. I'm just glad it wasn't more serious. I bought a set of old steel 27's from an old no name japanese 10 speed to use on this thing for the winter. Getting back up that hill with 37 gear inches was hard work.
I was at my place in Michigan this weekend. I am currently building up a fixie out of a 1986 Varsity frame. Its a lightweight lugged frame with aluminum bullhorns. so it weighs like 10 pounds or so. I was towing this on my burley flatbed behind my 1968 Schwinn Varsity. When I reassembled the trailer, I apparently didn'y tighten the wheels up enough, and the left skewer shook itself loose. SO I get to a point on a 25mph road where the road goes down into a river valley. It is downhill for about 1/3 of a mile (steep). I got the rig up to 33 mph when I started to feel the trailer bounce around alot, since the load weighed less than the trailer itself. Then I the trailer hit a bump, go up in the air,and then I heard dragging. I thought I flipped the trailer, that would have been a first. I braked quickly, then a 20" wheel with an offset hub, went flying downhill past me. I watched as it rolled downhill and then I pushed my riginto the grass next to the road. Some people pulled up in a Mercedes and gave me a ride half way down the hill to where the wheel rolled into some brush. I walked back uphill and reattached the wheel. I made the dropout was okay, and that both wheels were on extra tight and i continued downhill. I'm just glad it wasn't more serious. I bought a set of old steel 27's from an old no name japanese 10 speed to use on this thing for the winter. Getting back up that hill with 37 gear inches was hard work.
#4
I was carrying on the rack a trailer tire it fell off rolled across two lanes went up a kwall over that went down a 25 foot embankment and landed in a creek.
Funny thing is I watch this thing zipp like a race car since I was doing 25mph. I had to do a power stop.
Of course after I got it and it was ok.
Funny thing is I watch this thing zipp like a race car since I was doing 25mph. I had to do a power stop.
Of course after I got it and it was ok.
#5
Conservative Hippie
Joined: Mar 2005
Posts: 4,268
Likes: 0
From: Wakulla Co. FL
That 15 mph max speed is just to limit the manufacturer's liability. These trailers tow fine at speeds higher than that. I've had my Burley Flatbed up into the high 30's-almost 40. The thing to remember with trailers is if you have to stop quickly you have the load on the trailer pushing you from behind. Things can get a little exciting if you want to stop quickly with rim brakes in the rain while towing a trailer.
#7
Senior Member
Joined: Jul 2006
Posts: 597
Likes: 18
From: Milwaukee
Bikes: Fred cycles
That 15 mph max speed is just to limit the manufacturer's liability. These trailers tow fine at speeds higher than that. I've had my Burley Flatbed up into the high 30's-almost 40. The thing to remember with trailers is if you have to stop quickly you have the load on the trailer pushing you from behind. Things can get a little exciting if you want to stop quickly with rim brakes in the rain while towing a trailer.
#8
Thread Starter
Senior Member
Joined: Aug 2007
Posts: 487
Likes: 0
From: Chi-town
Bikes: Fixie conversion, a few 10 speeds, a trailer, I GT Transeo for utilitarian riding
Does the trailer cause the back tire to break loose & swing out? Or what...? It's a concern.. I tow one. I'm a heavy guy so maybe less likelihood of problems than for a lightweight pilot? I'm thinking: avoid braking hard with the front wheel, use the back more forcefully than w/o the trailer.
In this situation, the trailer had the advantage, I weigh about 145+20 pound bike+slick high pressure tires on a slippery surface.
#9
Senior Member
Joined: Jul 2006
Posts: 597
Likes: 18
From: Milwaukee
Bikes: Fred cycles
Good point. With a positive tongue weight (trailer center of mass ahead of the trailer axle) there will be a centrifugal thrust on the bike through a turn even if you're not braking. All the worse if you're also braking.
If the center of mass of the trailer is behind the trailer axle (negative tongue weight -- shouldn't be loaded this way), there would be a centripetal (inward) thrust.
So... does the rule of thumb for automotive trailers apply to bikes? 10% of the weight of the trailer on the tongue? Maybe helps to minimize sideways thrust at the rear wheel of the bike. Not always easy to do depending on the shape of the load & of the trailer.
As I gain experience with the trailer & think about this stuff, I am growing less concerned with speed and more thoughtful about avoiding having the trailer cause me to go down
.
-Rich
If the center of mass of the trailer is behind the trailer axle (negative tongue weight -- shouldn't be loaded this way), there would be a centripetal (inward) thrust.
So... does the rule of thumb for automotive trailers apply to bikes? 10% of the weight of the trailer on the tongue? Maybe helps to minimize sideways thrust at the rear wheel of the bike. Not always easy to do depending on the shape of the load & of the trailer.
As I gain experience with the trailer & think about this stuff, I am growing less concerned with speed and more thoughtful about avoiding having the trailer cause me to go down

-Rich
#10
Conservative Hippie
Joined: Mar 2005
Posts: 4,268
Likes: 0
From: Wakulla Co. FL
Does the trailer cause the back tire to break loose & swing out? Or what...? It's a concern.. I tow one. I'm a heavy guy so maybe less likelihood of problems than for a lightweight pilot? I'm thinking: avoid braking hard with the front wheel, use the back more forcefully than w/o the trailer.

I've also towed some pretty heavy loads on my Burley Flatbed behind my Allez Elite without a problem.
Part of what Chicagoan ran into may have to do with the type of pavement he was on. When I was living on Okinawa it didn't take long (one rain) for me to discover that those roads are very slippery when wet. I later came to understand it's due to the crushed coral they use in the asphalt. There was a road near where I grew up that had crushed shell in it. That road was also very slippery when wet.
I have found the rear wheel doesn't have much braking power wet or dry, with or without a trailer, before locking up and losing traction, which reduces braking effectiveness. I only use the rear brake when I want to slow gradually.
Now there are trailer hitches and there are trailer hitches, and what I have found is that a hitch that connects lower on the bike at the axle is inherently more stable than a hitch that connects to the seatpost. My Wike Woody Wagon that my canoe or kayak ride on connects to the seatpost, which makes load distribution in the trailer much more critical for an safe, stable and enjoyable ride.
But that's not to say there's anything inherently wrong with a seatpost hitch. I will tow, and have towed, my canoe 3- almost 20 miles to go hunting and fishing. I just distribute the load so it feels a wee little bit heavy on the hitch. It's one of those things that get easier with practice, (cooler goes here, backpack goes here, shotgun goes here, anchor goes here, fishing rods go here, etc.) so play around with it a little bit.
Last edited by CommuterRun; 10-24-08 at 07:43 PM.
#11
Thread Starter
Senior Member
Joined: Aug 2007
Posts: 487
Likes: 0
From: Chi-town
Bikes: Fixie conversion, a few 10 speeds, a trailer, I GT Transeo for utilitarian riding
Exactly, had the pavement not been wet, the wheel wouldn't have locked up so easily. If I skid these tires when the ground is wet, it can be hard to control the skid without the trailer.Add a loaded trailer and you have a jack knife.
You shouldn't have any issues.
You shouldn't have any issues.







