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lumpus

lumpus
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Hi together!

I'm a little frustrated. I read in some forums that it is no problem to adapt a K1100 wheel to the K100. (ok, perhaps with an adapter..)
Now I got one with number 2 331 357 ....
First Problem is, the casted bolts for the brake disc. Ok, I can cut it off....
But there is also big difference in the offset of ~+17.5mm. Which means that I have to mill off 17.5mm on a lathe to get the original tracking line / alignment.

Has the K1200 the same offset?

Do I have the wrong wheel?

Thanks.

    

charlie99

charlie99
VIP
VIP
yes there is a big difference between rear wheels fitted to paralever type rear drives on k1100 and further to k1200 ...and the old bevel box fitted to k100

there is a thing that some know about...  to do with "a" and "b" designed rims ...to do with the offset ...
I cant explain better ...but with the big offset on the later rims it does appear to work ok .....it doesnt make sense but it does work
others may chime in with some advice

good luck


__________________________________________________
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 )
    

Rick G

Rick G
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I am in the process of doing just that except with a paralever rear end but I am sure there will not be enough meat to take that much off, it will leave very little metal for strength. The paralever sits quite a bit more to the right so will work. Also if you take that much from the wheel boss it will hit the swingarm.
The A & B that Charlie talks of is for the 3 spoke K1100 and K75s wheels so is of no concern.


__________________________________________________
"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
    

Mikewills

Mikewills
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I have recently bought this k1200 wheel after instruction that it'll fit my 1987 model without modifying it. Hoping this is correct as the bike isn't at my home so not sure when I'll get to try it on.
Rear wheel modification -  K1200 or K1100 on the K100? 86DB3BD5-8219-4AF4-8B42-916163F1F8BE



Last edited by Mikewills on Fri Jun 09, 2017 8:39 am; edited 1 time in total

    

lumpus

lumpus
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RicK G wrote:I am in the process of doing just that except with a paralever rear end but I am sure there will not be enough meat to take that much off, it will leave very little metal for strength. The paralever sits quite a bit more to the right so will work. Also if you take that much from the wheel boss it will hit the swingarm.
The A & B that Charlie talks of is for the 3 spoke K1100 and K75s wheels so is of no concern.

"Also if you take that much from the wheel boss it will hit the swingarm."

... this could be the next problem!

    

Rick G

Rick G
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admin
Mikewills wrote:I have recently bought this k1200 wheel after instruction that it'll fit my 1987 model without modifying it. Hoping this is correct as the bike isn't at my home so not sure when I'll get to try it on.
What width is the rim?


__________________________________________________
"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
    

jbt

jbt
Life time member
Life time member
K1100LT rim (3 width, 17 inch diameter) will fit K100 with no modification, as they were available as a "sport" option on K75.
K100RS1, K1100RS,  K1 rim (4.5 width, 18 inch) will fit with spacer  but there may be a light disalignment with the front and may not cope with the monolever swinging arm. BMW allows this light offset.
Others won't fit because of the huge offset with the fron't wheel.
Note that the  larger is the rear wheel, the worst is the handling...
I had tested all the configurations on my K1100LT, the best is the original one with a thin tyre and a 3 inch rim.

On any bike with a double swinging arm, you can fit an larger wheel if you have room enough. On a K , there's few room, and extra width should make you modify the position of the engine, gearbox and transmission in the frame to keep the wheels in line.

    

duck

duck
Life time member
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I think you may want to switch to a 4V center stand but don't have first hand experience so just throwing this out as something to consider.


__________________________________________________
Current stable:
86 Custom K100 (standard fairing, K75 Belly pan, Ceramic chromed engine covers, paralever)
K75 Frankenbrick (Paralever, K11 front end, hybrid ABS, K1100RS fairing, radial tires)
86 K75C Turbo w/ paralever
94 K1100RS
93 K1100LT
91 K1
93 K75S (K11 front end)
91 K75S (K1 front end)
14 Yamaha WR250R
98 Taxi Cab K1200RS
14 K1600GT
http://www.ClassicKBikes.com
    

Mikewills

Mikewills
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RicK G wrote:
Mikewills wrote:I have recently bought this k1200 wheel after instruction that it'll fit my 1987 model without modifying it. Hoping this is correct as the bike isn't at my home so not sure when I'll get to try it on.
What width is the rim?
It's a 5".
There's a few places on the internet that supports what I've been told that it'll fit. I'll just have to try it I suppose

    

Rick G

Rick G
admin
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jbt wrote:K1100LT rim (3 width, 17 inch diameter) will fit K100 with no modification, as they were available as a "sport" option on K75.
K100RS1, K1100RS,  K1 rim (4.5 width, 18 inch) will fit with spacer  but there may be a light disalignment with the front and may not cope with the monolever swinging arm. BMW allows this light offset.
Others won't fit because of the huge offset with the fron't wheel.
Note that the  larger is the rear wheel, the worst is the handling...
I had tested all the configurations on my K1100LT, the best is the original one with a thin tyre and a 3 inch rim.

On any bike with a double swinging arm, you can fit an larger wheel if you have room enough. On a K , there's few room, and extra width should make you modify the position of the engine, gearbox and transmission in the frame to keep the wheels in line.
K1100 and K75 3 spoke are not the same offset K1100 has Type A stamped in the reverse side of one of the spokes and K75 had type B stamped there. The offset is 14mm different.


__________________________________________________
"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
    

Rick G

Rick G
admin
admin
Mikewills wrote:
RicK G wrote:
Mikewills wrote:I have recently bought this k1200 wheel after instruction that it'll fit my 1987 model without modifying it. Hoping this is correct as the bike isn't at my home so not sure when I'll get to try it on.
What width is the rim?
It's a 5".
There's a few places on the internet that supports what I've been told that it'll fit. I'll just have to try it I suppose
It might bolt up OK but will be offset by around 20mm to the left. Depending on what tyre you use will depend on it interfering the swingarm.


__________________________________________________
"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
    

JR_K100RS

JR_K100RS
Life time member
Life time member
G'day Lumpus , take a look at this thread

https://www.k100-forum.com/t2713-wider-wheels-radial-tyres-on-a-k100

John Re

Melbourne Australia


__________________________________________________
Diamond Grey ( 617 ) 1987 K100RS ( European Delivery ) Original owner
    

Two Wheels Better

Two Wheels Better
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That thread has brought back some memories, JR. The red RS still wears that tyre size combo tho' now she's got Michelin Pilot Road III out back and an older PR2 up the front. I like them for their straight-line stability with relatively good turn-in, not as quick steering as the Conti Road Attacks, but not as planted as the Pirelli Angel tyres I first used. One day I'll whack the K100RS-16V Marzocchi forks, 17" front wheel and 305mm discs, K11 gearbox and Paralever I've got saved onto it and call it updated. The offset relationship between a Monolever and the K1100RS 4.5" wheel is minimal, but you best use a K11 centra stand and grind some of the left foot away as mentioned in the link.

Side note, my (K100 with K1200RS motor) Big Block Paralever uses a 5" K1200RS wheel (170/60ZR17 tyre, not a 180/55) and it sits centred with plenty of space between the tyre/rim and swingarm.

Next ride, October when I return home.


__________________________________________________
"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
    

robmack

robmack
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__________________________________________________
Robert
1987 K75 @k75retro.blogspot.ca
http://k75retro.blogspot.ca/
    

Rick G

Rick G
admin
admin
Two Wheels Better wrote:That thread has brought back some memories, JR. The red RS still wears that tyre size combo tho' now she's got Michelin Pilot Road III out back and an older PR2 up the front. I like them for their straight-line stability with relatively good turn-in, not as quick steering as the Conti Road Attacks, but not as planted as the Pirelli Angel tyres I first used. One day I'll whack the K100RS-16V Marzocchi forks, 17" front wheel and 305mm discs, K11 gearbox and Paralever I've got saved onto it and call it updated. The offset relationship between a Monolever and the K1100RS 4.5" wheel is minimal, but you best use a K11 centra stand and grind some of the left foot away as mentioned in the link.

Side note, my (K100 with K1200RS motor) Big Block Paralever uses a 5" K1200RS wheel (170/60ZR17 tyre, not a 180/55) and it sits centred with plenty of space between the tyre/rim and swingarm.

Next ride, October when I return home.
Ah Ha so the K1200RS rear wheel sits dead centre, good to know. Did you use the spacer?


__________________________________________________
"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
    

Two Wheels Better

Two Wheels Better
Moderator
Moderator
No spacer required.


__________________________________________________
"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
    

Rick G

Rick G
admin
admin
Hmmmm That makes me a very happy little Vegemite


__________________________________________________
"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
    

Two Wheels Better

Two Wheels Better
Moderator
Moderator
Rear wheel modification -  K1200 or K1100 on the K100? Imag4310
Paralever and 5" wide wheel with 170/60ZR17 tyre.


__________________________________________________
"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
    

Motorbike Mike

Motorbike Mike
Life time member
Life time member
lumpus wrote:Hi together!

I'm a little frustrated. I read in some forums that it is no problem to adapt a K1100 wheel to the K100. (ok, perhaps with an adapter..)
Now I got one with number 2 331 357 ....
First Problem is, the casted bolts for the brake disc. Ok, I can cut it off....
But there is also big difference in the offset of ~+17.5mm. Which means that I have to mill off 17.5mm on a lathe to get the original tracking line / alignment.

Has the K1200 the same offset?

Do I have the wrong wheel?

Thanks.
If I've read this correctly you are using a wheel from an R series Oilhead model. They had the same pattern wheels but the disc was bolted to the wheel-hence the disc mounting spigots on the casting.
I've got a 5.5" x 17 wheel in my K with a 180 section tyre using a Mono rear end.
I'm positive that all the rear wheels should run with the steel shim/spacer. It's there to stop the wheel and FD fretting.

Rear wheel modification -  K1200 or K1100 on the K100? Img_2711

Rear wheel modification -  K1200 or K1100 on the K100? Img_2710

    

jbt

jbt
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Very nice rim, I've never seen such one on a K. Who makes it?

    

Motorbike Mike

Motorbike Mike
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jbt wrote:Very nice rim, I've never seen such one on a K. Who makes it?
They were made by Astralite but sadly they've just closed up.

    

jbt

jbt
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Life time member
Thanks,
I've been searching for a long time for a rim in 4.00 width for K.
With a friend, we're building a race K100, for endurance races, but the rules forbid a rim wider than 4.00, so the 4.50 genuine one is too large.
Very difficult to find...
PVM made wheels with bolted on parts, so making possible to swap the rim itself on the hub, but they're also very,  very rare.

    

23Back to top Go down   Rear wheel modification -  K1200 or K1100 on the K100? Empty just started the project .. Wed Jun 28, 2017 4:31 pm

lumpus

lumpus
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Thanks a lot to all.
I found a K1200RS ... I try it and post the results ...
[url=https://servimg.com/view/19724992/1]Rear wheel modification -  K1200 or K1100 on the K100? S-l16010

    

Two Wheels Better

Two Wheels Better
Moderator
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jbt wrote:Thanks,
I've been searching for a long time for a rim in 4.00 width for K.
With a friend, we're building a race K100, for endurance races, but the rules forbid a rim wider than 4.00, so the 4.50 genuine one is too large.
Very difficult to find...
PVM made wheels with bolted on parts, so making possible to swap the rim itself on the hub, but they're also very,  very rare.
US-based Kosman racing fabbed up wider rear wheels for Y spoke-equipped K bikes. They're as rare as proverbial rocking horse poo, however.

Kosman Specialties link

Note on Kosman's site:
This process is now being done by Custom Metal Spinnings. Call Walt at 562-696-3602


__________________________________________________
"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
    

Scottybullet

Scottybullet
active member
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Looks like with a 170/60/17 rear it'll clear the swingarm I'll post pics as soon as i have a place to hide them. I have the rim bolted up no problem with just enough room if the tire is not wider than 6.5 inches across

    

Laitch

Laitch
Life time member
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Scottybullet wrote: I'll post pics as soon as i have a place to hide them.
That's a cryptic statement. Smile  You could post them as soon as your able by using the icon in the toolbar indicated by the red arrow in the attached image. Just Select them, then Send them, then Insert them. They'll be inserted wherever the cursor is in the Message box.
Rear wheel modification -  K1200 or K1100 on the K100? Screen22


__________________________________________________
1995 K75 90,000 miles
    

Two Wheels Better

Two Wheels Better
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Scottybullet wrote:Looks like with a 170/60/17 rear it'll clear the swingarm I'll post pics as soon as i have a place to hide them. I have the rim bolted up no problem with just enough room if the tire is not wider than 6.5 inches across
Pop your year/model into the signature area of your profile so if you have a question, or if you make a statement, the rest of us know what it's pertaining to: Monolover, Paralever, etc. Ta.


__________________________________________________
"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
    

Scottybullet

Scottybullet
active member
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Rear wheel modification -  K1200 or K1100 on the K100? Img_0514
Rear wheel modification -  K1200 or K1100 on the K100? Img_0515
Rear wheel modification -  K1200 or K1100 on the K100? Img_0516

    

Two Wheels Better

Two Wheels Better
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Moderator
Be prepared to modify (search heaps of threads about it on this forum) or remove entirely the centre stand to clear the tyre when using a 160/60ZR18 or 170/60ZR17 and corresponding wheels.


__________________________________________________
"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
    

Scottybullet

Scottybullet
active member
active member
Yeah I've lost many hours thus far.... Centre stand is long gone, Kickstand bent to suit. hope to finish mechanical this winter and then start the nightmare of electrical in the spring. 
Rear wheel modification -  K1200 or K1100 on the K100? 55985311

    

31Back to top Go down   Rear wheel modification -  K1200 or K1100 on the K100? Empty 170/60-17 tire on 5.5x17 K1200 rim Fri Oct 05, 2018 1:57 pm

Scottybullet

Scottybullet
active member
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Perfect with original K11 Oem 1mm spacer. I had a local shop throw on a used tire to check fitment..  not a lot of room for anything but it'll do. Dunlop Roadmaster 3 on order will have fitment results next week


Rear wheel modification -  K1200 or K1100 on the K100? Img_0518

    

Scottybullet

Scottybullet
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Here is my setup 1996 K1100LT mounted a K1200 5.5X17 rear rim(no oem spacer) with a dunlop roadmaster 3 170/60/17.  I actually gained 1 MM of spacing between the tire and the swingarm from the test tire I had mounted. 

It sits a smidgin off center but I could care less for the rides I'll be taking it on. 

Rear wheel modification -  K1200 or K1100 on the K100? 56096710
Rear wheel modification -  K1200 or K1100 on the K100? Img_0521
Rear wheel modification -  K1200 or K1100 on the K100? Img_0520

    

artyomka

artyomka
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Scottybullet wrote:Here is my setup 1996 K1100LT mounted a K1200 5.5X17 rear rim(no oem spacer) with a dunlop roadmaster 3 170/60/17.  I actually gained 1 MM of spacing between the tire and the swingarm from the test tire I had mounted. 

It sits a smidgin off center but I could care less for the rides I'll be taking it on. 

Rear wheel modification -  K1200 or K1100 on the K100? 56096710
Rear wheel modification -  K1200 or K1100 on the K100? Img_0521
Rear wheel modification -  K1200 or K1100 on the K100? Img_0520
Very nice! Thanks for posting! I was hesitating but after the photos uploaded I went and ordered a 5.5" wheel.

    

beachcomber550

beachcomber550
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There's a right load of cobblers spouted about "offsets". Rolling Eyes

All the various width rear wheels will fit the frames and as long as there's no interference with the driveshaft - there's NO issue.

Even the BMW OEM manual gives an offset value between front and rear wheel tracking. 

There's also NO requirement in the construction and use regs.  [ or UK MOT rules ] for the front and rear wheels to be on the same track. Aligned - of course, but track - no.

My bikes [ and Ben Kigham's racers ] have been running with that wheel combo for years without any issues.


__________________________________________________
" I used to be indecisive - now I'm not so sure"
    

beachcomber550

beachcomber550
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Scottybullet wrote:Here is my setup 1996 K1100LT mounted a K1200 5.5X17 rear rim(no oem spacer) with a dunlop roadmaster 3 170/60/17.  I actually gained 1 MM of spacing between the tire and the swingarm from the test tire I had mounted. 

It sits a smidgin off center but I could care less for the rides I'll be taking it on. 

Rear wheel modification -  K1200 or K1100 on the K100? 56096710
Rear wheel modification -  K1200 or K1100 on the K100? Img_0521
Rear wheel modification -  K1200 or K1100 on the K100? Img_0520


Not sure what a "smidgen" is in Canada .... about 10mm offset. That said makes absolutely NO difference to the handling ! Mine's been in use for 9 years and Ben Kingham has similar offset on his racers. Even the BMW OEM manual gives values for STOCK offsets !!


__________________________________________________
" I used to be indecisive - now I'm not so sure"
    

Rick G

Rick G
admin
admin
Even the BMW OEM manual gives values for STOCK offsets !!

Please supply the relevant document because I hear this often yet have been unable to find anything in any factory published document supporting the claim.
Please note at the moment I am not calling bullshit but just wish to see the published document.


__________________________________________________
"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
    

Laitch

Laitch
Life time member
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beachcomber550 wrote:Not sure what a "smidgen" is in Canada .... about 10mm offset. That said makes absolutely NO difference to the handling ! . . . Even the BMW OEM manual gives values for STOCK offsets !!
Rick G wrote:Please supply the relevant document because I hear this often yet have been unable to find anything in any factory published document supporting the claim.

This doesn't have much to impart but it's from the Repair Manual K75–K100LT All 2V Models, dated 4.1988. Is it relevant?
Rear wheel modification -  K1200 or K1100 on the K100? Bmw_2v10


__________________________________________________
1995 K75 90,000 miles
    

Rick G

Rick G
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What that reads to me is that 5mm offset is acceptable and 0mm is ideal.
I have repaired many damaged bikes and when they pull one way always then there is something wrong, usually a bent frame or swinging arm. I always did a string line on the wheels as a final check when they were reassembled.
I have ridden bikes that have been crashed then repaired by amateurs and can feel in the handling of the bike if the wheels are not tracking true.


__________________________________________________
"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
    

beachcomber550

beachcomber550
active member
active member
RicK G wrote:Even the BMW OEM manual gives values for STOCK offsets !!

Please supply the relevant document because I hear this often yet have been unable to find anything in any factory published document supporting the claim.
Please note at the moment I am not calling bullshit but just wish to see the published document.
 
My OEM manual is in the loft - as soon as  I locate it I will scan the relevant page and post up.

This is the White faced manual with the BMW logo. Look and you will find.

Logic tells us that ALL of the various width wheels that are fitted cannot be centralised simply by offset on the hub face - hence values given for offset tracking front to back. Or are we saying there are different frames for the 3" wheel and the 4.5", 5" etc.,etc. ?

The bullshit  [ that I am not calling ] is the mythical claims of bad handling .... ask Ben Kingham


__________________________________________________
" I used to be indecisive - now I'm not so sure"
    

Dai

Dai
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Also, both Tony Foale and BMW experimented with front/rear offsets in the 1990s. BMW's conclusion at the time was that it didn't affect handling and actually improved something-or-other, but way too much time has passed to remember what that was. The reason for not putting into production was that it was 'too radical'.

Well: while trying to turn up the reference for at least one of the above (failed), I did turn up an extremely interesting picture of a K-RT undergoing wind-tunnel testing. The fairing is covered in the usual white tufts to check wind flow, but the engine appears to be equipped with one silence per cylinder! I did just try to scan it but the book is a paperback and I'm unwilling to flatten the spine.

The book is

Motorcycle Tuning (Chassis) by John Robinson. ISBN 0-434-91724-9

The picture is on page 171 of the paperback edition. It's long out of print (1994) and what originally cost £5 is now going for north of £50, if you can find one.


__________________________________________________
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
    

beachcomber550

beachcomber550
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Dai wrote:Also, both Tony Foale and BMW experimented with front/rear offsets in the 1990s. BMW's conclusion at the time was that it didn't affect handling and actually improved something-or-other, but way too much time has passed to remember what that was. The reason for not putting into production was that it was 'too radical'.

Well: while trying to turn up the reference for at least one of the above (failed), I did turn up an extremely interesting picture of a K-RT undergoing wind-tunnel testing. The fairing is covered in the usual white tufts to check wind flow, but the engine appears to be equipped with one silence per cylinder! I did just try to scan it but the book is a paperback and I'm unwilling to flatten the spine.

The book is

Motorcycle Tuning (Chassis) by John Robinson. ISBN 0-434-91724-9

The picture is on page 171 of the paperback edition. It's long out of print (1994) and what originally cost £5 is now going for north of £50, if you can find one.

Dai.

voice of reason ...............

I've been designing and building / manufacturing both road / race cars and bikes for many years. I have seen MANY self build, prototype AND factory bikes with offset front to rear track. Makes not a scrap of difference as long as the wheels are parallel. That's the bit of string / plank of wood laid alongside the fattest wheel.

Check out Airheads at some stage with various different rear wheel widths.

I have to wonder why the detractors of this method fitted a bike up so equipped and tested it to give their results a valid opinion ?  Wink


__________________________________________________
" I used to be indecisive - now I'm not so sure"
    

beachcomber550

beachcomber550
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RicK G wrote:Even the BMW OEM manual gives values for STOCK offsets !!

Please supply the relevant document because I hear this often yet have been unable to find anything in any factory published document supporting the claim.
Please note at the moment I am not calling bullshit but just wish to see the published document.

Well Rick G for those unable or unwilling to do their research Laughing - here's the pages scanned from the FACTORY BMW OEM workshop manual - part# 01 51 9 799 101 ....a very useful volume for us long term Kay enthusiasts.

No Bullshit here. Cool

You'll see that BMW allow for 12mm max. offset .... mine was 10mm [ see my previous post ] with a 5" rim and 15mm with a 5.5" rim. IN 9 YEARS OF HARD RIDING THERE HAVE BEEN NO HANDLING / STEERING ISSUES.

Ben Kingham has won 3 back to back B.E.A.R.S.championships with such a set up. Didn't seem to bother him. Rolling Eyes

Rear wheel modification -  K1200 or K1100 on the K100? File

Rear wheel modification -  K1200 or K1100 on the K100? File

Rear wheel modification -  K1200 or K1100 on the K100? File


__________________________________________________
" I used to be indecisive - now I'm not so sure"
    

Rick G

Rick G
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Well Beachcomber550 when you figure out how to put up pictures then I will give you an answer.


__________________________________________________
"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
    

beachcomber550

beachcomber550
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RicK G wrote:Well Beachcomber550 when you figure out how to put up pictures then I will give you an answer.
 I'm seeing 3 images on my posting ???

If you CAN'T see them try the BM Riders forum ... on there too.


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" I used to be indecisive - now I'm not so sure"
    

Laitch

Laitch
Life time member
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beachcomber550 wrote:
RicK G wrote:Well Beachcomber550 when you figure out how to put up pictures then I will give you an answer.
 I'm seeing 3 images on my posting ???

If you CAN'T see them try the BM Riders forum ... on there too.
I can't see them either. Can you post a link to them on the BM Riders forum?


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1995 K75 90,000 miles
    

robmack

robmack
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I can't see the images either.  Looking at what you're trying to do Beachcomber, it's not going to work.  You're trying to imbed a URL into an IMG tag.  Furthermore, the URLs you're referencing needs the viewer here on K100 Forum to subscribe to the BMBikes website before access is granted.  Read the sticky about posting photos: https://www.k100-forum.com/t998-posting-pictures-and-movies


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Robert
1987 K75 @k75retro.blogspot.ca
http://k75retro.blogspot.ca/
    

Laitch

Laitch
Life time member
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beachcomber550 wrote:FACTORY BMW OEM workshop manual - part# 01 51 9 799 101 ....a very useful volume for us l

You'll see that BMW allow for 12mm max. offset .... mine was 10mm [ see my previous post ] with a 5" rim and 15mm with a 5.5" rim. IN 9 YEARS OF HARD RIDING THERE HAVE BEEN NO HANDLING / STEERING ISSUES.
In reply 37, the page extract I posted was from the BMW manual for 2V K models. The manual beachcomber is citing is for the K1100 so has a differing spec. One page from that manual is attached.

It's likely fair to say that these maximum offset specs were established for BMW's liability protection, that racers can do whatever works for them within the constraints of competition rules, and that performance of a setup for competition might be unsatisfactory performance on ordinary roads at ordinary speed.

Rear wheel modification -  K1200 or K1100 on the K100? K1100_11


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1995 K75 90,000 miles
    

beachcomber550

beachcomber550
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Laitch wrote:
beachcomber550 wrote:FACTORY BMW OEM workshop manual - part# 01 51 9 799 101 ....a very useful volume for us l

You'll see that BMW allow for 12mm max. offset .... mine was 10mm [ see my previous post ] with a 5" rim and 15mm with a 5.5" rim. IN 9 YEARS OF HARD RIDING THERE HAVE BEEN NO HANDLING / STEERING ISSUES.
In reply 37, the page extract I posted was from the BMW manual for 2V K models. The manual beachcomber is citing is for the K1100 so has a differing spec. One page from that manual is attached.

It's likely fair to say that these maximum offset specs were established for BMW's liability protection, that racers can do whatever works for them within the constraints of competition rules, and that performance of a setup for competition might be unsatisfactory performance on ordinary roads at ordinary speed.

Rear wheel modification -  K1200 or K1100 on the K100? K1100_11

As previously stated - I have used my modified Kay ON THE ROAD for 9 years in all sorts of riding conditions with NO PROBLEMS. Finis.


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" I used to be indecisive - now I'm not so sure"
    

Suzi Q

Suzi Q
Life time member
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Seeing as this thread is (still) about the possibilities of fitting wider rear wheels to a K, I'll add this because some future reader might find it useful.

The 5-spoke (best looking wheels ever) rims fitted to the K1200 are a common choice. They can be hard to get hold of, compared to the very similar looking wheels fitted to boxers from the same era. Most times though, people find they can't use boxer wheels for two reasons: boxer wheels have disc mounting posts cast onto the spokes (Ks don't - the disc is sandwiched between the wheel and the hub), and boxer wheels have too much left offset (sometimes described as 'A' and 'B' wheels - is this to make up the space for the 'missing' disc?)

Well, the problematic extra offset on a boxer wheel can itself be 'offset' by leaving out the k series disc, and using a boxer disc mounted on the wheel. I did this with a 5" boxer rim (there are 5.5" options out there too) and, with a bit of adjustment to the swingarm pivots, it was possible to get the left offset down to just 3mm.

This itself isn't without a bit of grief; the boxer disc has a smaller OD, but a boxer rear caliper is correct for this, and (in typical BMW style) fits straight on the caliper mounts on the bevel drive (K & boxer bevels are very similar). I had to shift the caliper and disc over to the left (spacers on the caliper, machined a bit off the disc mounting posts) but this was to clear a wider, non-standard shock, dunno if this would be necessary with a standard shock.

Rear wheel modification -  K1200 or K1100 on the K100? 00213


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Sometimes I'm not really Suzi Quatro.
    

beachcomber550

beachcomber550
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chris846 wrote:Seeing as this thread is (still) about the possibilities of fitting wider rear wheels to a K, I'll add this because some future reader might find it useful.

The 5-spoke (best looking wheels ever) rims fitted to the K1200 are a common choice. They can be hard to get hold of, compared to the very similar looking wheels fitted to boxers from the same era. Most times though, people find they can't use boxer wheels for two reasons: boxer wheels have disc mounting posts cast onto the spokes (Ks don't - the disc is sandwiched between the wheel and the hub), and boxer wheels have too much left offset (sometimes described as 'A' and 'B' wheels - is this to make up the space for the 'missing' disc?)

Well, the problematic extra offset on a boxer wheel can itself be 'offset' by leaving out the k series disc, and using a boxer disc mounted on the wheel. I did this with a 5" boxer rim (there are 5.5" options out there too) and, with a bit of adjustment to the swingarm pivots, it was possible to get the left offset down to just 3mm.

This itself isn't without a bit of grief; the boxer disc has a smaller OD, but a boxer rear caliper is correct for this, and (in typical BMW style) fits straight on the caliper mounts on the bevel drive (K & boxer bevels are very similar). I had to shift the caliper and disc over to the left (spacers on the caliper, machined a bit off the disc mounting posts) but this was to clear a wider, non-standard shock, dunno if this would be necessary with a standard shock.

Rear wheel modification -  K1200 or K1100 on the K100? 00213

Yes Chris timely advice / warning. I went down that route as well when I was investigating all the options 10 years ago !  For some reason [?] the Oilhead 5 spoke Wobblies were cheaper than the Kay wheels. Maybe as much as 25%. There was no research already done  back in the day that I could refer to - so platforms such as this are invaluable to peeps today who might not want to be in the "let's all be different together" club.

I think the answer to this debate [?] is that those who have obviously tried out this format and come to the conclusion that in their view handling is compromised [ Ben Kingham still there ? ]will not want to repeat their experience and those of us who like to tinker and experiment - will.

Did I ever mention fitting the Wire spoked GS wheels to my Kay ............ probably best not to go there.  Evil or Very Mad


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