hi guys i seem to have quite a lot of play in the backlash ..if you put your bike on mainstand put in first gear move wheel till it locks how much play in cm does your bike have..it would help me greatly to see if mine is excessive...kind regards jim...1986 k100rs

I have not measured the backlash, but it's quite important.
Measuring the backlash at the wheel is not a good way to check the drive shaft and splines.
The only way to check it is to remove the final drive for a visual inspection.
If you are so concerned, this means that you have not checked it for a while and certainly need to grease the splines.
Greasing the rear splines takes roughly 1 hour, and if you want to remove the swing arm and do the front ones it will take you another 2 hours.
If you remove the swing arm, it's a good time to clean the back of the transmission and coat the gear position switch with silicone. after years on the road, this switch has the tendency to be permeable to water.

The procedure to remove the differential is explained here

hi. k100rs stood 8 years till now changed lots of things on bike, passed MOT yesterday.. i have moly geased rear splines on shaft but not front and clutch splines,,did 10 mile yesterday to MOT garage and back..1st gear judder and clunk when setting of,,after that goes through all gears smooth as silk,,downshifting smooth as silk..no vibes only took bike to 60mph though,, clutch nice and light and no clutch slip of any kind..also i am not a mechanic but will have a go..this is reason for needing help..and the backlash question.or will it clear on more mileage that will be done..reason front splines not done dont think i am experanced enough...regards...jim

Jim,

If you removed your final drive and reassembled it on your own, you are qualified to remove the swing arm and why not the gear box.
Check my K100 rebuilt page and come back with questions.
The front splines of the drive shaft should be OK as they are big splines. The clutch ones should be greased to avoid problems ($$$$$) in the future.
The tricky part is to refit the gear box onto the engine but I showed an easy way in the following post
One of the thing to pay attention is to maintain the clutch lever (on the back of the gear box) into position. You just attach it to the frame with a piece of wire before you remove the exhaust.
If you start the job and have any problems, we will help you. Just have a digital camera ready to show us where you are stocked.
It could be good to take pictures of the whole procedure and show us how an "inexperienced" rider is able to successfully do the job.
Looking for congratulating you on a job well done.

Bert

Crazy Frog wrote:Jim,

If you removed your final drive and reassembled it on your own, you are qualified to remove the swing arm and why not the gear box.
Check my K100 rebuilt page and come back with questions.
The front splines of the drive shaft should be OK as they are big splines. The clutch ones should be greased to avoid problems ($$$$$) in the future.
The tricky part is to refit the gear box onto the engine but I showed an easy way in the following post
One of the thing to pay attention is to maintain the clutch lever (on the back of the gear box) into position. You just attach it to the frame with a piece of wire before you remove the exhaust.
If you start the job and have any problems, we will help you. Just have a digital camera ready to show us where you are stocked.
It could be good to take pictures of the whole procedure and show us how an "inexperienced" rider is able to successfully do the job.
Looking for congratulating you on a job well done.

Bert

hi thanks bert..i have ridden bikes 40 years now..not a mechanic though ...anyway bert i am going to do the job myself in a few weeks .. what causes that judder when you let the clutch out in first gear..regards jim

sandman jim wrote:hi guys i seem to have quite a lot of play in the backlash ..if you put your bike on mainstand put in first gear move wheel till it locks how much play in cm does your bike have..it would help me greatly to see if mine is excessive...kind regards jim...1986 k100rs

6 cm... if you get more

ok i am a car mechanic and i still ask for advice on here befor i try it, so dont think u got no hope of doing it, the clutch shutter u are talking about in a car can be caused buy a bad engine mount, warped flywheel or pressure plate, a bad uni jiont. are the main causes,..... the engine mout lets the motor bounce under load ie taking off in first gear (hi load) and not in other gears because the load is lower, the flywheel being warped or p/plate is not so noticeable at higer rpm,,
not saying this is ur problem, but the set up on a k-bike is verry similar to a car, bert will correct me if i am wrong, hope my thought helps

"6 cm... if you get more "
geez think mine has about 12

You'd better have a look at the splines... or at the "cardan" (i'm not sure of the english term) it's the part just at the entry of the gear box...

universal jiont / cardon

the rear spines r ok i ihave packed them with molly when i had my diff apart

So have a look at the cardan, or you must check the differential

diff good has next to 0 back lash just done it