Safety flaw in Raptor trikes...

(copy of an email sent to )

I have one of the earlier Henderson versions, but the pics on your site
suggest the flaw still exists...

The torque from the front brakes was resisted by a small bolt beside the
front wheel axle. This bolt was

a) too small;
b) too close to the axle;
c) too weak (not grade 5, even!)
and
d) loaded in shear

It broke.

It broke when my ten-year-old was riding - he might have weighed around a
hundred pounds. He lost control and was dumped out of the trike.
Fortunately he was not going very fast and was on the sidewalk, so he was
only scraped up a bit.

When this bolt breaks, the steering arm moves forward, control is lost, and
the rider can easily be thrown forward into the path of whatever he/she was
braking to avoid.

I fixed this by maiking a pair of pieces of 1/8" x 1.25" aluminium go from
the lower rod-end mount to a point on the steering arm just forward of the
handle mount. This piece is attached to the lower rod end and with three
small bolts on the steering arm.

This fix changes the structure of the whole steering arm and axle-mounting
plate to a triangle. The brake torque will now be resisted by the much
larger section of threaded rod that goes throught the crossbar.

It's a cheap and simple fix. I strongly suggest you modify the trikes you
sell, and contact previous purchasers to offer to retrofit such a fix.

I previously posted about the accident, the flaw, and the fix on
alt.rec.bicycles.recumbent. As you live in the USofA you must be aware of
the possibility of liabilty claims should another such incident occur,
especially as both the cause and the fix are public knowledge.

(this post copied to alt.rec.bicycles.recumbent)

Richardson or Henderson??

"jtaylor" wrote in message
...
(copy of an email sent to )

I have one of the earlier Henderson versions, but the pics on your site
suggest the flaw still exists...

The torque from the front brakes was resisted by a small bolt beside the
front wheel axle. This bolt was

a) too small;
b) too close to the axle;
c) too weak (not grade 5, even!)
and
d) loaded in shear

It broke.

It broke when my ten-year-old was riding - he might have weighed around a
hundred pounds. He lost control and was dumped out of the trike.
Fortunately he was not going very fast and was on the sidewalk, so he was
only scraped up a bit.

When this bolt breaks, the steering arm moves forward, control is lost,
and
the rider can easily be thrown forward into the path of whatever he/she
was
braking to avoid.

I fixed this by maiking a pair of pieces of 1/8" x 1.25" aluminium go from
the lower rod-end mount to a point on the steering arm just forward of the
handle mount. This piece is attached to the lower rod end and with three
small bolts on the steering arm.

This fix changes the structure of the whole steering arm and axle-mounting
plate to a triangle. The brake torque will now be resisted by the much
larger section of threaded rod that goes throught the crossbar.

It's a cheap and simple fix. I strongly suggest you modify the trikes you
sell, and contact previous purchasers to offer to retrofit such a fix.

I previously posted about the accident, the flaw, and the fix on
alt.rec.bicycles.recumbent. As you live in the USofA you must be aware of
the possibility of liabilty claims should another such incident occur,
especially as both the cause and the fix are public knowledge.

(this post copied to alt.rec.bicycles.recumbent)

"Joshua Goldberg" wrote in message
...
Richardson or Henderson??

Ooops, Richardson, flaw is the same...

"jtaylor" wrote in message
...
(copy of an email sent to )

I have one of the earlier Henderson versions, but the pics on your site
suggest the flaw still exists...

The torque from the front brakes was resisted by a small bolt beside the
front wheel axle. This bolt was

a) too small;
b) too close to the axle;
c) too weak (not grade 5, even!)
and
d) loaded in shear

It broke.

It broke when my ten-year-old was riding - he might have weighed around
a
hundred pounds. He lost control and was dumped out of the trike.
Fortunately he was not going very fast and was on the sidewalk, so he
was
only scraped up a bit.

When this bolt breaks, the steering arm moves forward, control is lost,
and
the rider can easily be thrown forward into the path of whatever he/she
was
braking to avoid.

I fixed this by maiking a pair of pieces of 1/8" x 1.25" aluminium go
from
the lower rod-end mount to a point on the steering arm just forward of
the
handle mount. This piece is attached to the lower rod end and with
three
small bolts on the steering arm.

This fix changes the structure of the whole steering arm and
axle-mounting
plate to a triangle. The brake torque will now be resisted by the much
larger section of threaded rod that goes throught the crossbar.

It's a cheap and simple fix. I strongly suggest you modify the trikes
you
sell, and contact previous purchasers to offer to retrofit such a fix.

I previously posted about the accident, the flaw, and the fix on
alt.rec.bicycles.recumbent. As you live in the USofA you must be aware
of
the possibility of liabilty claims should another such incident occur,
especially as both the cause and the fix are public knowledge.

(this post copied to alt.rec.bicycles.recumbent)

Nedavno jtaylor pise:

| Richardson or Henderson??
|
| Ooops, Richardson, flaw is the same...

I am trying to build my own trike, and seeing your post, i looked up
for Raptor trike on google. One of googles results come up with with
the following photo:

http://www.ezdenver.com/raptor/steering.jpg

I was wondering if anyone knows where I can buy... Hmmm... English is
not my native language, and I do not knew what's it called. I need the
thing int the wheel center with axle going through it but big enough
that wheel can be mounted like in the photo (without the fork).

Anyone knows?


--
___ ____
/__/ / \ ** Registrovani korisnik Linuksa #291606 **
/ / \/ /\ \ ** Registered Linux user #291606 **
/__/\____/--\__\ ** http://counter.li.org/ **

Nedavno Yvan pise:

| I am trying to build my own trike, and seeing your post, i looked up
| for Raptor trike on google. One of googles results come up with with
| the following photo:
|
| http://www.ezdenver.com/raptor/steering.jpg
|
| I was wondering if anyone knows where I can buy... Hmmm... English is
| not my native language, and I do not knew what's it called. I need the
| thing int the wheel center with axle going through it but big enough
| that wheel can be mounted like in the photo (without the fork).

It looks like what I need is called a HUB. So, i need a hub with a
stronger axle.




--
___ ____
/__/ / \ ** Registrovani korisnik Linuksa #291606 **
/ / \/ /\ \ ** Registered Linux user #291606 **
/__/\____/--\__\ ** http://counter.li.org/ **

"Yvan" wrote in message
news:20050325165626.45e927e5@localhost...

It looks like what I need is called a HUB. So, i need a hub with a
stronger axle.


Wheelchair hubs are commonly used for one-sided mounting. The Raptor ones
are steel - not so good because the flanges are thin and the spoke hole
corners do not deform like aluminium ones do - they break spokes.

You can buy BMX hubs with 14mm axles, or some Formula disc hubs come with
12mm sealed bearings and you can pull the QR and axle and use your own 12mm
bolt.

It looks like what I need is called a HUB. So, i need a hub with a
stronger axle.


Wheelchair hubs are commonly used for one-sided mounting. The Raptor ones
are steel - not so good because the flanges are thin and the spoke hole
corners do not deform like aluminium ones do - they break spokes.