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1Back to top Go down   Interesting mod on K1100 exhaust Empty Interesting mod on K1100 exhaust Tue Feb 20, 2018 7:58 pm

Rick G

Rick G
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__________________________________________________
"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 1999 K1100 LT with a Big Block 1200
    

2Back to top Go down   Interesting mod on K1100 exhaust Empty Re: Interesting mod on K1100 exhaust Tue Feb 20, 2018 10:58 pm

Point-Seven-five

Point-Seven-five
Life time member
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Having recently purchased a fairly low mileage '91 K100RS with the exhaust in (so far) uncracked condition and hearing of all the cracked headers I have a couple of questions.

First, where do the cracks appear?   Are they in the header pipes themselves or in the weld at the collector?  

Second, does anyone have a good idea of what causes the cracks?  Is it vibration, thermal expansion, or some issue related to the installation of the exhaust system on the bike like a misadjusted or missing mount.  My old '92 K100RS had three OEM exhaust systems fail in 4 years back in the early '90's before a Remus system was installed.  Not knowing the history of the new bike I am wondering if there is a problem in the future.


__________________________________________________
Present: 1991 K100RS "Moby Brick Too"
 
Past:
1994 K75RT "Ilsa, She Wolf of the SS"
1988 K100RS SE "Special Ed"
1994 K75S "Cheetos"
1992 K100RS "Moby Brick" R.I.P.
1982 Honda FT500
1979 Honda XR185
1977 Honda XL125
1974 Honda XL125
1972 OSSA Pioneer 250
1968 Kawasaki 175
    

3Back to top Go down   Interesting mod on K1100 exhaust Empty Re: Interesting mod on K1100 exhaust Tue Feb 20, 2018 11:56 pm

Rick G

Rick G
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I have been through 3 systems on the K1100LT but that system has been modified with a front section of a K100 8V system put onto the K1100 rear section. You can see the clamps that come from a K100.  An interesting mod that I'd not even considered.


__________________________________________________
"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 1999 K1100 LT with a Big Block 1200
    

4Back to top Go down   Interesting mod on K1100 exhaust Empty Re: Interesting mod on K1100 exhaust Wed Feb 21, 2018 12:24 am

Point-Seven-five

Point-Seven-five
Life time member
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I noticed that as well.  My reason for asking was to determine if it would make sense to modify my system to head off the problem before it occurs. 

Right now I have an early model K100 exhaust with a damaged muffler that could provide the header pipes and clamps to do the mod.  My reason for asking whether the problem is vibration or thermal expansion related is that cutting the headers and clamping them would be a good way to relieve the stresses of unequal expansion in the header pipes. 

Not sure how to control vibration, I did see the recent posting about putting hose clamps around the header pipe bundle and have done that, but there is no proof that it will really help.


__________________________________________________
Present: 1991 K100RS "Moby Brick Too"
 
Past:
1994 K75RT "Ilsa, She Wolf of the SS"
1988 K100RS SE "Special Ed"
1994 K75S "Cheetos"
1992 K100RS "Moby Brick" R.I.P.
1982 Honda FT500
1979 Honda XR185
1977 Honda XL125
1974 Honda XL125
1972 OSSA Pioneer 250
1968 Kawasaki 175
    

5Back to top Go down   Interesting mod on K1100 exhaust Empty Re: Interesting mod on K1100 exhaust Wed Feb 21, 2018 4:15 am

MartinW

MartinW
Life time member
Life time member
The hose clamp around the header pipes originated with police bikes. Apparently it changed the frequency of the vibration, not sure what state instigated it but I believe it was effective.
Regards Martin.

    

6Back to top Go down   Interesting mod on K1100 exhaust Empty Re: Interesting mod on K1100 exhaust Wed Feb 21, 2018 4:37 am

charlie99

charlie99
VIP
VIP
RicK G wrote:I have been through 3 systems on the K1100LT but that system has been modified with a front section of a K100 8V system put onto the K1100 rear section. You can see the clamps that come from a K100.  An interesting mod that I'd not even considered.

yes , looks like a possible solution on a standard 16 valve system rick


__________________________________________________
cheezy grin whilst riding, kinda bloke ....oh the joy !!!! ...... ( brick aviator )

'86 K100 RT..#0090401 ..."Gerty" ( Gertrude Von Clickandshift ) --------O%O
'86 k100 rs.. #######..  "Fred " (f(rame) red ) ( Fredrick leichtundschnell ) - -
bits and pieces from many kind friends across the k100 world ...with many thanks ..
1987 k100rs ########   "Red"  - (red sports rs TWB style )
1989 K100rt #009637   "Black Betty"  (naked rt ala Nigel , now sporting an rs main fairing )
    

7Back to top Go down   Interesting mod on K1100 exhaust Empty Re: Interesting mod on K1100 exhaust Wed Feb 21, 2018 10:38 am

Point-Seven-five

Point-Seven-five
Life time member
Life time member
I'm thinking that if I was to do the mod before the pipes cracked, it would be possible to just cut the header pipes and install some replacements with clamps from an early K100 exaust.

I have some header pipes from the old exhaust I had on my bike.  Have to go out this morning and take some measurements.


__________________________________________________
Present: 1991 K100RS "Moby Brick Too"
 
Past:
1994 K75RT "Ilsa, She Wolf of the SS"
1988 K100RS SE "Special Ed"
1994 K75S "Cheetos"
1992 K100RS "Moby Brick" R.I.P.
1982 Honda FT500
1979 Honda XR185
1977 Honda XL125
1974 Honda XL125
1972 OSSA Pioneer 250
1968 Kawasaki 175
    

8Back to top Go down   Interesting mod on K1100 exhaust Empty Re: Interesting mod on K1100 exhaust Wed Feb 21, 2018 12:19 pm

Two Wheels Better

Two Wheels Better
Moderator
Moderator
I have a complete, un-cracked header/muffler from a '93 K1100RS with oxygen sensor and one small ding in the muffler. Seventy five green bucks plus postage to whomever needs it. Located near Tacoma, Washington.
Interesting mod on K1100 exhaust 20180210
Interesting mod on K1100 exhaust 20180211


__________________________________________________
"A long ride is the answer to a question you will soon forget!" ~ Anonymous
1977 R75/7-100, '93 K11/K12 Big Block, '93 K1100RS, '95 R100 Mystic, '96 K1100RS, 2 x '98 K1200RS, '06 K1200R & '09 K1300GT
    

9Back to top Go down   Interesting mod on K1100 exhaust Empty Re: Interesting mod on K1100 exhaust Wed Feb 21, 2018 8:03 pm

Rick G

Rick G
admin
admin
Point-Seven-five wrote:I'm thinking that if I was to do the mod before the pipes cracked, it would be possible to just cut the header pipes and install some replacements with clamps from an early K100 exaust.

I have some header pipes from the old exhaust I had on my bike.  Have to go out this morning and take some measurements.
The pipes probably don't have enough space to do that. The K100 8V pipes are spaced a bit wider to allow for the clamps also I think the #4 pipe wont have enough straight section as it enters the muffler.

From what I gather it is a resonant frequency plus age that makes them crack. On my recently retired K1100 I welded a strap around all 4 pipes about 3 inches forward of the collector and haven't had any problem since but haven't ridden it for 6 months.


__________________________________________________
"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 1999 K1100 LT with a Big Block 1200
    

10Back to top Go down   Interesting mod on K1100 exhaust Empty Re: Interesting mod on K1100 exhaust Thu Feb 22, 2018 3:16 am

Point-Seven-five

Point-Seven-five
Life time member
Life time member
RickG, I find it interesting that you say that age is a factor.  The service history on my '92 K100RS indicated that three exhaust systems cracked on it in it's first four years.  I doubt any of them was more than a couple years old.

I am putting hose clamps around the pipes on my "new" '92 K100RS as was mentioned as the "police" fix.  One is about 4" or so in front of the collector, and the other is around the headers for cylinders 1,2,&3 and is between cylinders 3 and 4.  If vibration is a factor, I want to make sure the two longest pipes are damped as much as possible.


__________________________________________________
Present: 1991 K100RS "Moby Brick Too"
 
Past:
1994 K75RT "Ilsa, She Wolf of the SS"
1988 K100RS SE "Special Ed"
1994 K75S "Cheetos"
1992 K100RS "Moby Brick" R.I.P.
1982 Honda FT500
1979 Honda XR185
1977 Honda XL125
1974 Honda XL125
1972 OSSA Pioneer 250
1968 Kawasaki 175
    

11Back to top Go down   Interesting mod on K1100 exhaust Empty Re: Interesting mod on K1100 exhaust Thu Feb 22, 2018 6:38 am

92KK 84WW Olaf

avatar
Life time member
Life time member
Vibration and resonance is a well known issue with stainless steel.

Unfortunately the same issue also affected stainless steel exhausts in cars which is one of the reasons they still use mild steel.

Splitting the silencer and manifold certainly helps because the 2v engines don't suffer the problem.

I looked at a lot of options including frequent replacement of the rubber damper mountings but that still doesn't guarantee a cure.

Plan B was to take it off and split it and get a collector and silencer. I wanted to eliminate the problem altogether.

However before I got that far a complete Remus for the K1100 presented itself on eBay at a buy it now price not to be refused as it was much less than the cost of a collector and silencer. Maybe I should say muffler as the Remus isn't exactly a silencer but its darn nice.

Would I go down the road of welding it up? No because it will keep happening.


__________________________________________________
1992 K100LT 0193214 Bertha Blue 101,000 miles
1984 K100RT 0022575 Brutus Baja Red 578 bought 36,000 now 89,150 miles
1997 K1100LT 0188024 Wotan Mystic Red 689 58,645 now 106,950 miles Deceased.
1983 K100RS 0011157 Fricka 606 Alaska Blue 29,495 miles Damn K Pox Its a Bat outta Hell Now 58,200 miles. 
1996 K1100LT 0233004 Lohengrin Mystic Red 38,000 miles currently 51,800 miles.
1983 K100RS 0004449 Odette R100 colours 58,000 miles. Sprint fairing now 63,390 miles

Past:
1968 Yamaha 80 YG1
1971 Yamaha 125 YAS-1
1968 Honda 125 SS
1970 Honda CD 175
1973 Honda CB500-4
Honda CX 500
    

12Back to top Go down   Interesting mod on K1100 exhaust Empty Re: Interesting mod on K1100 exhaust Thu Feb 22, 2018 7:08 am

BobT

BobT
Life time member
Life time member
92KK 84WW Olaf wrote:Unfortunately the same issue also affected stainless steel exhausts in cars which is one of the reasons they still use mild steel.

Not had a mild steel exhaust on a car for years! Think that you will find that they have been using stainless for about 20 years now. Stainless is not just one thing, there are many different specs of stainless steel, you should know that!

    

13Back to top Go down   Interesting mod on K1100 exhaust Empty Re: Interesting mod on K1100 exhaust Thu Feb 22, 2018 8:06 am

Dai

Dai
Life time member
Life time member
I'm with Bob; all of my Guzzis have had stainless sytems as has LFB and the Blandit. The only one that has given trouble and needed replacing was the Suzuki but that, by owner consensus, was down to poor design where the collector box meets the silencer pipe. One Guzzi exhaust system is now over thirty years old. Looking out of the window, it's now obvious that the wee Nissan Note sitting in the drive also has a stainless system.


__________________________________________________
1983 K100 naked upgraded to K100LT spec after spending time as an RS and an RT
1987 K100RT
Others...
1978 Moto Guzzi 850-T3, 1979 Moto Guzzi 850-T3 California,1993 Moto Guzzi 1100ie California
2020 Royal Enfield Bullet 500
    

14Back to top Go down   Interesting mod on K1100 exhaust Empty Re: Interesting mod on K1100 exhaust Thu Feb 22, 2018 9:42 am

Point-Seven-five

Point-Seven-five
Life time member
Life time member
I've had cars with stainless exhaust since the mid '80's and never had an issue with cracking. 

My '92 K100 had a Remus exhaust on it when I got it.  Took it off after a year because it was rather loud with a sharp bark to the exhaust note that I found embarrassing when riding through town.


__________________________________________________
Present: 1991 K100RS "Moby Brick Too"
 
Past:
1994 K75RT "Ilsa, She Wolf of the SS"
1988 K100RS SE "Special Ed"
1994 K75S "Cheetos"
1992 K100RS "Moby Brick" R.I.P.
1982 Honda FT500
1979 Honda XR185
1977 Honda XL125
1974 Honda XL125
1972 OSSA Pioneer 250
1968 Kawasaki 175
    

15Back to top Go down   Interesting mod on K1100 exhaust Empty Re: Interesting mod on K1100 exhaust Thu Feb 22, 2018 10:29 am

92KK 84WW Olaf

avatar
Life time member
Life time member
My wee cars have mild steel.......German and French......

Maybe they send the cheap ones over here or maybe its because they are diesel........


__________________________________________________
1992 K100LT 0193214 Bertha Blue 101,000 miles
1984 K100RT 0022575 Brutus Baja Red 578 bought 36,000 now 89,150 miles
1997 K1100LT 0188024 Wotan Mystic Red 689 58,645 now 106,950 miles Deceased.
1983 K100RS 0011157 Fricka 606 Alaska Blue 29,495 miles Damn K Pox Its a Bat outta Hell Now 58,200 miles. 
1996 K1100LT 0233004 Lohengrin Mystic Red 38,000 miles currently 51,800 miles.
1983 K100RS 0004449 Odette R100 colours 58,000 miles. Sprint fairing now 63,390 miles

Past:
1968 Yamaha 80 YG1
1971 Yamaha 125 YAS-1
1968 Honda 125 SS
1970 Honda CD 175
1973 Honda CB500-4
Honda CX 500
    

16Back to top Go down   Interesting mod on K1100 exhaust Empty Re: Interesting mod on K1100 exhaust Thu Feb 22, 2018 10:37 am

BobT

BobT
Life time member
Life time member
92KK 84WW Olaf wrote:My wee cars have mild steel.......German and French......

Maybe they send the cheap ones over here or maybe its because they are diesel........
Forgot to mention that all my cars have been diesels since 1981 and all German or French.

    

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