Re: P38 Seat and Zip Ties

Scott Yoho Fri, 20 Jun 2008 09:08:57 -0500
> Once my lightning P38 gets wet, the seat fabric (and/or the cording
> holding it in place) stretches

I have a Stealth, not a P38, but I have the same problem. The fabric
doesn't even need to get wet: just high humidity will make it stretch
significantly more than usual.

> enough so the seat back rubs on the rear tire[....] Under the seat
> fabric I added a grommeted "underseat" made of Phifertex fabric

> http://store.valueweb.com/servlet/poweron/Detail?no=3D82

> which presumably doesn't stretch when wet). In addition to keeping
> the seat from getting close to the wheel this also acts as a
> protective barrier if the seat and tire do meet (the underseat will
> rub on the tire first).

IMHO fenders provide a much more robust seat/tire barrier (not to
mention seat/rain barrier 

> I've also replaced the cording with zip ties through the grommets in
> both the P38 seat and the underseat.

I've done that also, but mainly because I got tired of

- replacing the whole seat cord whenever I put the bike down 

- retensioning the whole seat cord due to stretch

It's just a whole lot easier to replace a few zipties than a seat
cord. Plus retensioning is much less necessary, and trivial/precise
with a third hand.

> The new problem is that some of the zip ties seem to work loose
> after a few rides. 

What do you mean by "work loose"? I've found that new zipties

* often break ("infant mortality  

* stretch a bit

So when you first re/lace a seat, be sure to tension both sides
equally (i.e. pull the same amount through the head of the tie): this
is easy to do with a third hand. Then don't clip them! Wait a few
rides to let them stretch (and to replace the ones that die young),
then go back and retension them all, and clip the ends as desired.

> Maybe I used the wrong ties? Mine are the "Commercial Electric"
> brand, distributed by Home Depot[....] The packaging makes the
> following claims:

> - Indoor/Outdoor
> - Meets Military Specification
> - UV Resistant
> - 75lb Tensile Strength
> - Double Lock Grip (33% stronger)

> They're roughly 5/32" (I believe that's 4mm) wide. I think I could
> go a little wider,

Not necessary. I also get my zipties @ HD or wherever. Just be sure to
get ones marked UV resistant, and tensile strength >= 50 lb. (FWIW I
currently have Thomas & Betts' 7" "Ty-Rap Premium Tie/UV.") Buy a bag
of count >= 100, and keep the rest with your travel tools (whatever
you keep in your seatback bag) for use when needed. (Zipties usually
break in ones or twos, but occasionally, e.g. after a sharp cold snap,
they can break en masse.)

HTH, Tom Roche <Tom_Roche <at> pobox.com>
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