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1Back to top Go down   Shock Absorber lower brace K1100 Empty Shock Absorber lower brace K1100 on Sat Jun 27, 2020 1:19 am

RicK G

RicK G
VIP
VIP
I have been asked on a few occasions lately to do a drawing of the brace I made to prevent the lower stud on the rear shock snapping when subjected to Aussie roads.
Apparently in some countries round the world this is unheard of but I have seen this 4 times now and one of them was on my bike and it is not an experience I wish to repeat when the rear wheel locks up and the suspension collapses.

Shock Absorber lower brace K1100 Shock_10


__________________________________________________
"Man sacrifices his health in order to make money.
Then he sacrifices money to recuperate his health.
And then he is so anxious about the future that he does not enjoy the present; the result being that he does not live in the present or the future; he lives as if he is never going to die, and then dies having never really lived."   Dalai Lama


Bikes 1993 K1100 LT, 1998 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki X 2 for now
    

2Back to top Go down   Shock Absorber lower brace K1100 Empty Re: Shock Absorber lower brace K1100 on Sat Jun 27, 2020 1:20 pm

brickrider2

brickrider2
Life time member
Life time member
Thanks for that, Rick!   cheers cheers


__________________________________________________
1996 K1100LT
    

3Back to top Go down   Shock Absorber lower brace K1100 Empty Re: Shock Absorber lower brace K1100 on Sat Jun 27, 2020 3:13 pm

Two Wheels Better

Two Wheels Better
Moderator
Moderator
Here's what it looks like from the top. The bottom edge, as Rick says, is angled to accommodate the final drive's falling away taper.
Shock Absorber lower brace K1100 Shocks12
Rick retrieved me, Pamela and busted rear shockie stud K100RS - Monolever - from the roadside near Stanthorpe Queensland several years back. Since then I've fitted Sidecar Paul's piece to my RS and Rick's novel piece to Big Block - Paralever.
Shock Absorber lower brace K1100 Imag3511
Here's what the Monolever looked like by the side of the road with traffic flying past and us in the relative safety of the first available gutter.
Shock Absorber lower brace K1100 Imag3512
Rick, after trailering us back to his remote station in the beautiful and rugged Granite Belt near the Qld/NSW border, got to work extracting the busted stud and cleaned out the threads - no real damage, thankfully - then screwed in a longer stud he'd made previously, in preparation for the triangular piece which was fitted next trip back Down Under.


__________________________________________________

Sometimes I lie awake at night, and I ask, "What can I do to keep my life from going by so fast?" Then a voice comes to me that says, "Try slowing down at the corners." 

~Charlie Brown

1970 R60/5, '77 R75/7-R100, '85 K100'87 K75C, '87 K100RS, '93 K11-K12 Big Block, '93 K1100RS, '95 R100-Mystic, '96 K1100RS, '98 K1200RS, '00 K1200RS, '02 K1200RS, '03 K1200GT, '04 R1150R'04 R1150RT, '05 K1200S, '06 K1200R, '07 K1200R, '09 K1300GT & 2013 R1200RT-Polizei  - Beemers owned still or sold.

    

4Back to top Go down   Shock Absorber lower brace K1100 Empty Re: Shock Absorber lower brace K1100 on Sat Jun 27, 2020 7:02 pm

Point-Seven-five

Point-Seven-five
Life time member
Life time member
What is the grade, if any, of the OEM stud?  Judging from the price it's not made from anything exotic.  Would it be an improvement to just go to grade 8.8 or 10.9 stud?

McMaster Carr has grade 10.9 threaded rod for a price that would allow me to make 3 studs for about $5 each.


__________________________________________________
Present:
1994 K75RT
1991 K100RS
1988 K100RS SE

Past:
1994 BMW K75S
1992 BMW K100RS
1982 Honda FT500
1979 Honda XR185
1977 Honda XL125
1974 Honda XL125
1972 OSSA Pioneer 250
1968 Kawasaki 175
    

5Back to top Go down   Shock Absorber lower brace K1100 Empty Re: Shock Absorber lower brace K1100 on Sat Jun 27, 2020 7:55 pm

Dai

Dai
Life time member
Life time member
If you have the option you would be better making a genuinue stud i.e. with a non-threaded portion that's the same length as the shock eye. The problem with threaded rod is that there one pressure point per thread to start damaging the rod eye (I was going to say 'screw things up' but...) and the area taking the shear load is rod diameter minus thread depth i.e. something like 8.25mm on a 10mm threaded rod.


[Edit] can't spell shear... Shocked



Last edited by Dai on Sun Jun 28, 2020 10:43 am; edited 1 time in total


__________________________________________________
'83 K100 upgraded to K100RS spec, '87 K100RT
Others...
'78 Moto Guzzi 850-T3, '79 Moto Guzzi 850-T3 California,'93 Moto Guzzi 1100ie California
    

6Back to top Go down   Shock Absorber lower brace K1100 Empty Re: Shock Absorber lower brace K1100 on Sat Jun 27, 2020 8:47 pm

Two Wheels Better

Two Wheels Better
Moderator
Moderator
I wondered about a harder screw being used but thought while it might be strong enough to take a harsher hit or heavier load, another more important weakness is the aluminium case of the final drive. The studs often snap off clean but they also can take a chunk out of the case below the surface, rendering an easy fix impossible by the side of the road, or even in the average garage with hand tools.


__________________________________________________

Sometimes I lie awake at night, and I ask, "What can I do to keep my life from going by so fast?" Then a voice comes to me that says, "Try slowing down at the corners." 

~Charlie Brown

1970 R60/5, '77 R75/7-R100, '85 K100'87 K75C, '87 K100RS, '93 K11-K12 Big Block, '93 K1100RS, '95 R100-Mystic, '96 K1100RS, '98 K1200RS, '00 K1200RS, '02 K1200RS, '03 K1200GT, '04 R1150R'04 R1150RT, '05 K1200S, '06 K1200R, '07 K1200R, '09 K1300GT & 2013 R1200RT-Polizei  - Beemers owned still or sold.

    

7Back to top Go down   Shock Absorber lower brace K1100 Empty Re: Shock Absorber lower brace K1100 on Sat Jun 27, 2020 9:53 pm

DadofHedgehog

DadofHedgehog
Silver member
Silver member
@brickrider2 wrote:Thanks for that, Rick!   cheers cheers
+1.


__________________________________________________
PRESENT:
1995 K75T.  I am the 3d owner.  Bought it in June 2019 with 6,242 miles on the odo.
1991 K100RS 4-valve attached to a 1990 Flexit sidecar. I am at least the 3d owner. Bought with 21,00+ miles on bike's odo.

PAST:
old (indeterminate age) Ural + sidecar
1997 Buell S3T Thunderbolt
1982 BMW R100CS
1974 Kawasaki KZ400
1970 Suzuki Titan
    

8Back to top Go down   Shock Absorber lower brace K1100 Empty Re: Shock Absorber lower brace K1100 on Sun Jun 28, 2020 3:43 am

RicK G

RicK G
VIP
VIP
10.9 or 10.10 is far too hard and will snap in short order 8.8 is the correct grade for that type of stud with the lateral force exerted on it.
Like TWB said they can and do break inside the housing, the K75RT my wife has did exactly that about 12 years ago and left us stranded on the roadside for 3 days while I got a replacement drive sent from home.


__________________________________________________
"Man sacrifices his health in order to make money.
Then he sacrifices money to recuperate his health.
And then he is so anxious about the future that he does not enjoy the present; the result being that he does not live in the present or the future; he lives as if he is never going to die, and then dies having never really lived."   Dalai Lama


Bikes 1993 K1100 LT, 1998 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki X 2 for now
    

9Back to top Go down   Shock Absorber lower brace K1100 Empty Re: Shock Absorber lower brace K1100 on Sun Jun 28, 2020 10:10 am

DadofHedgehog

DadofHedgehog
Silver member
Silver member
@RicK G wrote:I have been asked on a few occasions lately to do a drawing of the brace I made to prevent the lower stud on the rear shock snapping when subjected to Aussie roads.
Apparently in some countries round the world this is unheard of but I have seen this 4 times now and one of them was on my bike and it is not an experience I wish to repeat when the rear wheel locks up and the suspension collapses.

Shock Absorber lower brace K1100 Shock_10
Rick, an added detail of dimension measurements between the hole edges, the left edge, the right edge, the top edge and the bottom edge on the vertical piece, as well as the dimension of the horizontal pieces, would be useful for a machinist / fabricator. Would adding these be possible?


__________________________________________________
PRESENT:
1995 K75T.  I am the 3d owner.  Bought it in June 2019 with 6,242 miles on the odo.
1991 K100RS 4-valve attached to a 1990 Flexit sidecar. I am at least the 3d owner. Bought with 21,00+ miles on bike's odo.

PAST:
old (indeterminate age) Ural + sidecar
1997 Buell S3T Thunderbolt
1982 BMW R100CS
1974 Kawasaki KZ400
1970 Suzuki Titan
    

10Back to top Go down   Shock Absorber lower brace K1100 Empty Re: Shock Absorber lower brace K1100 on Sun Jun 28, 2020 10:26 am

Point-Seven-five

Point-Seven-five
Life time member
Life time member
For $5 I guess a new stud could be an annual maintenance item.  Make it part of the spline lube.


__________________________________________________
Present:
1994 K75RT
1991 K100RS
1988 K100RS SE

Past:
1994 BMW K75S
1992 BMW K100RS
1982 Honda FT500
1979 Honda XR185
1977 Honda XL125
1974 Honda XL125
1972 OSSA Pioneer 250
1968 Kawasaki 175
    

11Back to top Go down   Shock Absorber lower brace K1100 Empty Re: Shock Absorber lower brace K1100 on Sun Jun 28, 2020 10:31 am

RicK G

RicK G
VIP
VIP
If you are going to get someone to make and fit one then the diameter of the hole in from the edge is the acceptable engineering standard (12mm hole is 12mm in from the edge) but with the thickness of the material being 8mm then 10mm would be acceptable as the only force is downwards and as for the lower edge, well that will depend on the width of the lower shock eye which governs how far in towards the drive housing the plate goes so that is left to the maker. You will need to take the shock, drive and drawing to them.


__________________________________________________
"Man sacrifices his health in order to make money.
Then he sacrifices money to recuperate his health.
And then he is so anxious about the future that he does not enjoy the present; the result being that he does not live in the present or the future; he lives as if he is never going to die, and then dies having never really lived."   Dalai Lama


Bikes 1993 K1100 LT, 1998 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki X 2 for now
    

12Back to top Go down   Shock Absorber lower brace K1100 Empty Shock absorber lower brace K1100 on Mon Jun 29, 2020 8:08 pm

redrockmania

redrockmania
Silver member
Silver member
Regarding snapping fastening bolts / threaded rod, mention was earlier made of two high tensile standards: 8.8 and 10.9. There is a higher tensile strength available, 12.9. Re a Husqvarna TE610 ie I had, there were reports of the 8.8 mounting bolts for foot pegs snapping and the fix was to fit 12.9 bolts which solved the problem.

    

13Back to top Go down   Shock Absorber lower brace K1100 Empty Re: Shock Absorber lower brace K1100 on Mon Jun 29, 2020 8:41 pm

RicK G

RicK G
VIP
VIP
Horses for courses and 8.8 is the best to use a 12.9 will snap like a carrot. I would use a mild steel bolt there in preference to a 12.9.
A 12.9 would be right at home used for a cylinder head bolt where there is no lateral load and in that regard it is very strong but if you try to bend it then the carrot would bend more without breaking but an 8.8 will if used for a cylinder head bolt just keep stretching until it pulled in half before getting to the correct tension.


__________________________________________________
"Man sacrifices his health in order to make money.
Then he sacrifices money to recuperate his health.
And then he is so anxious about the future that he does not enjoy the present; the result being that he does not live in the present or the future; he lives as if he is never going to die, and then dies having never really lived."   Dalai Lama


Bikes 1993 K1100 LT, 1998 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki X 2 for now
    

14Back to top Go down   Shock Absorber lower brace K1100 Empty Re: Shock Absorber lower brace K1100 on Mon Jun 29, 2020 8:45 pm

RicK G

RicK G
VIP
VIP
Horses for courses and 8.8 is the best to use a 12.9 will snap like a carrot. I would use a mild steel bolt there in preference to a 12.9.
A 12.9 would be right at home used for a cylinder head bolt where there is no lateral load and in that regard it is very strong but if you try to bend it then the carrot would bend more without breaking but an 8.8 will if used for a cylinder head bolt just keep stretching until it pulled in half before getting to the correct tension.


__________________________________________________
"Man sacrifices his health in order to make money.
Then he sacrifices money to recuperate his health.
And then he is so anxious about the future that he does not enjoy the present; the result being that he does not live in the present or the future; he lives as if he is never going to die, and then dies having never really lived."   Dalai Lama


Bikes 1993 K1100 LT, 1998 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki X 2 for now
    

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