My K has been running really well, and yesterday after 400km my K started making a dry/scraping noise from either the gearbox or diff. The strange thing is that you only hear it when decelerating. At idle or under acceleration it is quiet.

I am slightly stumped
Graeme

hi graemem

you have checked the oils in both the bevel box and gearbox ?

might be worth a look at the universal joint on the drive shaft ...and the lubrication of the splines both ends of the drive shaft also .

also check the pinion shaft for moovement (for - aft ) my previous one had about 2 - 3 mm moovement allowing the pinion to moove off the big diffgear ...and of corse oil leaks at the input bearing of the bevel box .

i dont have a lot of history regarding the output bearings of the gearbox ..but could be worth a thought . look for any oil leaks around that area .but the rubber boot that joins the swingarm to g/box would hide that from view .

Hi Charlie

I have replaced the oil on both the gearbox and diff because I also thought that might be the cause but it's still there. I will look at your other suggestions tomorrow it's 23:05pm here at the moment.

Thanx
Graeme

Sounds like it could be the disc and caliper making that noise.
Check the pads for lining thickness and also check to see if the wheel has any play, grab it top and bottom and see if it has any wobble. If that is lose then the wheel will change its orentation to the caliper and could cause a scraping noise.

charlie99 wrote:hi graemem

you have checked the oils in both the bevel box and gearbox ?

might be worth a look at the universal joint on the drive shaft ...and the lubrication of the splines both ends of the drive shaft also .

I put a coin on the uni-joint.

And I bet another one it falls off.

Hi All

Thanks for all the good responses. It would appear that my pinion has too much movement what size socket does the pinion nut use. It looks like a 36mm is this correct?

Thanks once again for all the good advice.

Graeme

I think 36 is right but there is also a 4 prong socket in there as well. That pinion bearing is a parallel roller bearing so just tightening the nut wont bake the shaft tight you will need to replace the bearing. The usual recommendation here is to just buy another drive but I am not sure ifthat is a viable option in SA.
Not sure what year your bike is (maybe put model in your signature line so all can tell at a glance) but when buying be careful to get the one with the correct spline on the pinion shaft. It will be a 16 or 20 spline the 16 being the earlier drive till the end of 86 I think.
There are some on Ebay US now ranging from $150 - $400. Check out the ratio first it is stamped on the housing near the joint with the swinging arm and will probably be 32 11 or 31 11. It shows the number of teeth on the crown wheel and pinion.

Hi Rick

Thanks for the advice I have obtained the new bearings so I will be installing them quickly and hopefully that will solve my problem.

I will be quiet for a while as laptops and oily hands don't mix. Will let everyone know how it went.

Graeme

Hi Graeme,

36mm it is, and for getting the seal retaining ring out you need something like the tool on the right of the two photos. The same tool (33-1-700) is used on most airheads, the K series and the later R series (R11xx). The tool on the left is only used on the pre-paralever airheads so ignore it.




Mike

If you need a simple FD locking tool, have a look at this:-

http://k100rt.aforumfree.com/t3247-simple-bevel-box-locking-tool

Cheers,

Paul.

Hi all

After much searching I have found a K standing in a shed well looked-after but standing. The bike had been stripped of all plastics and lights with the intention of racing it, thankfully it only raced twice.

And now she's mine all mine, I am going to keep her as a donor bike for my K100RS, starting with the F/D and rear shock. My donor bike has a newly refurbished unit on it as well as the original exhaust and rear shock in a "spares" box.

Greetings
Graeme

Good news Graeme there just isn't anything loke a donor bike. Did the stripped off plastic come with the corps or was it already gone.

Hi Rick

Unfortunately the plastics are not available but at least everything else is in great nick.

Greetings
Graeme