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subframe upgrade
Posted: Mon Nov 11, 2002 9:51 am
by Chris Krok
> The thing I am confused about is that the instructions
> say to drill one side thru to the other, but there
> isn't enought metal in the skinny center portion.
> Do later KLRs have separate bolt lugs?
> Am I supposed to drill all the way across or cut the center out?
Don't cut the center out, you need support to keep the frame tube from
pinching together. Another person found the same narrow clearance
problem on an older bike (Arden?), but said that the drill only came
through on one wall of the center section, and he ran the bolt through
and it was fine. Can you get an actual diameter measurement of the
center section?
Drilling through from either side should give you better centering.
Krokko
--
Dr. J. Christopher Krok
John Lucas Adaptive Wind Tunnel
Caltech MS 205-45, Pasadena, CA 91125
subframe upgrade
Posted: Fri Dec 12, 2003 7:26 am
by garalpar@webtv.net
Hi, I switched my subframe bolt to stainless steal bolts. S/S must be
better than stock? has anybody tried this? or think it`s not a big
enough of an upgrade?
GARY PARECE ,98 Concours 101k , 2001 VFR 4K mi.,2002 Suzuki DRZ 400 E,
2001 KLR 650 1K
subframe upgrade
Posted: Fri Dec 12, 2003 8:08 am
by Zachariah Mully
On Fri, 2003-12-12 at 08:26, garalpar@... wrote:
> Hi, I switched my subframe bolt to stainless steal bolts. S/S must be
> better than stock? has anybody tried this? or think it`s not a big
> enough of an upgrade?
No. Most readily available SS fasteners are
subframe upgrade
Posted: Fri Dec 12, 2003 8:36 am
by Zachariah Mully
On Fri, 2003-12-12 at 09:08, Zachariah Mully wrote:
> On Fri, 2003-12-12 at 08:26, garalpar@... wrote:
> > Hi, I switched my subframe bolt to stainless steal bolts. S/S must be
> > better than stock? has anybody tried this? or think it`s not a big
> > enough of an upgrade?
>
> No. Most readily available SS fasteners are 12.9's from Jake to replace the existing bolts or get the upgrade kit
> from Krokko.
This just in from Jake:
"The strength of the toughest grade of SS fasteners falls somewhere
between SAE Grade 2 and 5. SAE Grade 8 equals Metric Grade 10.9, and
is 150,000 PSI steel. I provide Metric Grade 12.9 subframe bolts,
which are 170,000 PSI.
Jake"
So in fact, you've downgraded the subframe on your bike, Gary. I believe
even the stockers at 10.9's.
Z
DC
A5X
A12X
subframe upgrade
Posted: Fri Dec 12, 2003 9:46 am
by wannabsmooth1
Gary,
Depends on what grade of stainless the bolts are. If you torqued
them, with a little loctite you're "probably" better off than stock.
I know Chris Krok (on this list) sells an upgrade kit with good
quality fasteners.
Mike
Eagle Mfg & Eng
San Dieo, Ca.
--- In
DSN_klr650@yahoogroups.com, garalpar@w... wrote:
> Hi, I switched my subframe bolt to stainless steal bolts. S/S must
be
> better than stock? has anybody tried this? or think it`s not a big
> enough of an upgrade?
>
> GARY PARECE ,98 Concours 101k , 2001 VFR 4K mi.,2002 Suzuki DRZ
400 E,
> 2001 KLR 650 1K
subframe upgrade
Posted: Fri Dec 12, 2003 10:45 am
by Chris Krok
> From: garalpar@...
> Subject: Subframe upgrade
>
> Hi, I switched my subframe bolt to stainless steal bolts. S/S must be
> better than stock? has anybody tried this? or think it`s not a big
> enough of an upgrade?
Stainless is actually weaker than any carbon alloy steel:
http://www.bigcee.com/reference.html
The stock bolts are 10.9, so 12.9 is the only swappable upgrade (unless
you can find 14.9, but they're not an accepted standard).
Krokko
--
Dr. J. Christopher Krok
John Lucas Adaptive Wind Tunnel
Caltech MS 205-45, Pasadena, CA 91125
subframe upgrade
Posted: Fri Dec 12, 2003 11:24 am
by Thor Lancelot Simon
On Fri, Dec 12, 2003 at 08:26:25AM -0500, garalpar@... wrote:
> Hi, I switched my subframe bolt to stainless steal bolts. S/S must be
> better than stock? has anybody tried this? or think it`s not a big
> enough of an upgrade?
This is a common misconception about stainless steel. In fact, all else
being equal, all common stainless steels have _less_ tensile strength than
the hardened carbon steel alloys that most fasteners are made of.
You'd have trouble finding stainless bolts that even matched the strength
of the Grade 8 bolts Kawasaki uses for most applications on the bike. The
original subframe and other critical bolts are probably better than that.
If you feel like doing some drilling, you can upgrade to 10mm bolts, at
which point stainless is probably a reasonable choice. However, the
simplest option by far is to use high-strength 8mm bolts like the Metric
Blue bolts that Chris and, I think, Jake supply (this is the "lite blue"
kit from Big Cee).
The lower subframe bolts pick up a fair amount of salt spray around here
in the winter, so I'd be a bit leery of using stainless bolts there anyway
(particularly 316 -- 18/8 might be safer) because of chloride
stress-corrosion cracking, which can lead to sudden failure under very
light loads.
The usual failure mechanism for the subframe bolts seems to be that one
of the lower bolts, which the factory doesn't even LocTite *at all*,
vibrates loose or even out. This puts far more load on the upper bolts,
and one of those eventually shears. If you're replacing the subframe
bolts or even just tightening the ones the factory installed, be sure
to use thread locker on *all* of them.
The bike is amazingly rideable even with one of the lower subframe bolts
completely missing -- you can guess how I know...

subframe upgrade
Posted: Fri Dec 12, 2003 1:00 pm
by garalpar@webtv.net
Hi, Thanks for the info.. I`ll be calling jake.
GARY PARECE ,98 Concours 101k , 2001 VFR 4K mi.,2002 Suzuki DRZ 400 E,
2001 KLR 650 1K
subframe upgrade
Posted: Fri Dec 12, 2003 2:01 pm
by bkowalca
Or you can got to Home Depot and buy a 3/8"x5 1/2" UNC grade 5
bolt and a self-locking nut for a couple of bucks.
I installed this earlier in the year, put on 15,000kms of hard
riding, 700kms of that with bags on the back on my wife on the back,
300kms of that on real offroad trails, with 100km of that sandy
whoops and such. I have had no problems with the bike FULLY loaded
on harsh terrain. Oh, and this isn't another fairy tale.
Bryan K
A14
--- In
DSN_klr650@yahoogroups.com, garalpar@w... wrote:
> Hi, Thanks for the info.. I`ll be calling jake.
>
> GARY PARECE ,98 Concours 101k , 2001 VFR 4K mi.,2002 Suzuki DRZ
400 E,
> 2001 KLR 650 1K
subframe upgrade
Posted: Fri Dec 12, 2003 3:45 pm
by wannabsmooth1
Chris,
Commonly available stainless bolts are weaker....
For instance - my stainless lever is heat treated to over 220ksi.
Mike
Eagle Mfg & Eng
San Diego, Ca.
--- In
DSN_klr650@yahoogroups.com, Chris Krok wrote:
>
> > From: garalpar@w...
> > Subject: Subframe upgrade
> >
> > Hi, I switched my subframe bolt to stainless steal bolts. S/S
must be
> > better than stock? has anybody tried this? or think it`s not a
big
> > enough of an upgrade?
>
> Stainless is actually weaker than any carbon alloy steel:
>
http://www.bigcee.com/reference.html
>
> The stock bolts are 10.9, so 12.9 is the only swappable upgrade
(unless
> you can find 14.9, but they're not an accepted standard).
>
> Krokko
>
> --
> Dr. J. Christopher Krok
> John Lucas Adaptive Wind Tunnel
> Caltech MS 205-45, Pasadena, CA 91125