Hello to all. I'm very pleased to be a member of your community!
It's my first bm bike, a k100 1985 with 204000km! I did buy it for cheap (700$) a couple of week ago, with a small problem.
The 6 rivets on the output shaft are broken! So, here is my question: how much can cost an 12 rivets units ? (used...) and what i would prefer to do is to repair that unit. 2 solutions are possible. 1 fill the elongated hole buy a professional welder (aluminium i think) and then drill new hole and put new rivets... or second possibility is to turn the part in aluminium a litle bit and drill 6 new holes and put 6 news rivets...
what do you think! do i'm wasting time! or ....
Thanks for any idea
Serge

Serge, if you search the site there is a conversation on upgrading to the stronger 12 rivet shaft, which is a stronger design. You need the shaft, a different bearing and seal I think, but easy to do if the other one is already out.

ya the broken one is out of the engine. but you know i would prefer to repair the one i have (money money and angain money!). i know that if i drill 6 new holes i'll probably have to mesh the two gear with the same advance so that the rubber inside are damping at the right moment....
Serge

Right. You might want to talk to a....... good Harley mechanic. HD's used to use a similar set up on the output shaft and mechanics were able to re-rivet them. I had a Harley mechanic tighten up my rivets, but I don't know how well it worked yet because I haven't run the bike since I put it back together.

ah cool man... there is a harley mecanic not far from my shop, i'll show him that! thanks for the idea...
i'll update when i know more
Serge

my guy said dont tell your bmw friends where you got this done, i don't want the word to get out. I only work on Harleys.

ok no prob! i'll keep that secret for me!
Thanks

This is very interesting considering that a new output shaft is about $600.

Well the proof is in the pudding, and I haven't had a taste yet.

so i went to see the harley guy! and no luck! he send me to a machine shop!
I'll go there tomorow, to see what they think about that. But i think i'll do it buy my self. I'll have to find 6 steel rivets... i'll tell you more later.
Serge

I have seen this discussion before and having had a brief flirtation with riveting in my Airforce training days it might be worth talking to what we used to call Aircraft Metal Workers who specialise in that area.

There is a wide variety of riveting materials and methods available and I would suspect even some of the blind rivets would be more than adequate.

Depending on how badly the holes are worn you may be able to ream them out until they are circular and fit oversize rivets rather than drilling out new holes.

an image here

This is the worst output shaft that I ever seen. I guess you are in need for a replacement.

Bert

man don't tell me that! i'm going to do a miracle! I have all the winter to work on that, so it's not in a rush... i've looked on ebay and i can find a used engine complete for aprox. 400$... or i have acces to copart, and if i take my time, i can find a crashed bike for the same price 3 or 4 hundred. But i'll sleep on that and will come with a nice solution( probably i'll try to drill 6 new holes), and when it will be fixed i'll come to your place and we will drink a beer!
Serge

other picture...


and a box full of pieces.... one day i'll have a bike!

I recognise the box 'o parts for sure! I would also agree with Bert that you output shaft looks very bad. But it won't cost you much to find out if your plan to re-rivet will work, so have at it. Also, if you didn't take out the rivets, then they fell into the sump. You will need to confirm you have found ALL of them.

ok. when i bought the bike, the rivets were broken. i found 5 in the engine i'll have to investigate more accurately to find the last one, or if fell in the oil pan when i drain the oil.
Serge

Keep watching eBay. I have a 12-rivet shaft that I paid £20 for, just waiting until I have enough space to fit it (bike outside now)

Hello again...
on year now i did repaired the shaft with 6 bolts... all is ok.
i've got vibration, perhaps b'cause i did lost the balance shaft position... i did put it there, i do not have any arrow or dot.... it vibes but not too bad. i should try an other bike to compare!
Thanks.