Rear hub

[Jeremiah31]

I just bought a 1996 mz scorpion 660 sport a couple of weeks ago and i was out riding today and the rear sprocket came off the hub, look like all the bolts just snapped off. This is my first bike and i don’t know anything about bikes. But I’m learning, looks like i need a new hub. Anyone possibly know where i can get one ASAP or know of any other bikes that has the same I’d be able to use on the bike, I’m currently living in south Cali and closest people i know is 1200 miles from me the bike is my only transportation rn so need to get this fixed ASAP.

[droy]

wow - never see that before.

That said - did the bolts just back out of the read hub threaded hole?? I've seen one bolt back off before - it will rub on the inside of the swingarm.

can you post a few more pictures of the bolt holes??

[droy]

wow - never see that before.

That said - did the bolts just back out of the read hub threaded hole?? I've seen one bolt back off before - it will rub on the inside of the swingarm.

can you post a few more pictures of the bolt holes??

[Puffs]

Following a biased and flawed moderator choice (someone posting aggressive personal attacks is rewarded, while my technical posts are removed - behind my back & without any justification!), I have withdrawn from this forum.

[breakwellmz]

Hi.
That`s rather rash advice to some who admits to having little experience especially without seeing what damage the hub might have, he will also require high tensile bolts as replacements as well if it proves to be that simple.
Cheers.

[Jeremiah31]

One bolt snapped off for sure. But all the bolts came off somehow, the bikes parked at a Costco parking lot rn but I’m gonna try to get some more bolts for it for now and see if that will at least let me get it to where i need to get to until i can find a new part I’m not sure what caused it, maybe the person i got it from hed the chain to tight. But rode perfectly until then it’s a great running bike just the fairings are tore to hell and the wind screens missing but hopefully I’ll be able to get it looking good again eventually. Thanks for the input guys I’ll post more pics of the issue here in a few I’m getting ready to head over now

[droy]

use blue thread lock on all those bolts

Let us know how it turns out

[Jeremiah31]

Here’s another pic

[droy]

get some 8mm bolts in there (these are some "captive" nuts in the hub that they thread into). you can see that the sprocket holes are oblong so the bolts been loose for some time.

Also at a minimum get some lube on that chain or ideally replace the chain and both sprocket . Its long overdue - that sprocket is very worn and chain doesn't have much life left.

The folks here can point to replacement parts if your having trouble.

Good luck

[DAVID THOMPSON]

those captive nuts may not be totally captive when the hub is out of the bike
and if so may need replaced also if its been loose fore a while

and the bearings need checked and some repacking or replacements

looks rode hard and put away very wet and abused

[Jeremiah31]

So the new nuts and bolts worked thankfully, ya it’s a work in progress i just got it a couple weeks ago. Paid only $900 and an iPad for it, only needs small things fixed mechanically wise runs pretty good starts every time,but cosmetics is a different story haha. Thanks for all the help and advise, also I’m going to have someone check the back wheel for me tomorrow to make sure i put it on straight and chains not too tight or loose

[Jeremiah31]

Pics

[breakwellmz]

Fixed already?
I think you got off lightly there!

[Puffs]

Hi.
That`s rather rash advice to some who admits to having little experience especially without seeing what damage the hub might have, he will also require high tensile bolts as replacements as well if it proves to be that simple.
Cheers.

Is it? Is it really any more difficult than getting a few bolts in there & ride the thing home? Is the solution dependent on the experience of the owner? If the OP doesn't feel confident himself, maybe someone else could do it. Anyway, if the OP feels offended, my apologies.

You ask advice. Then harvest opinions: use what you like, ignore what you don't. But always stay in charge yourself.

Come home, take the wheel out check the bearings, replace the nuts. Yes use thread lock, maybe in combination with new locking/non-slipping nuts (which I now learn are called 'captive'). High tensile bolts? Yes, as anyone can see (see links to miraculis.de elsewhere on this forum), the book says "DIN 933 M8x35-10.9-A4K hexagonal bolt" so that seems an M8 bolt of 35mm long, of the 10.9 class (a yield strength of 940 and tensile strength of 1040 MPa, anyway, pretty strong). I don't know what 'A4K' means, but 'A4' means stainless, so 'A4K' may indicate a surface treatment to prevent corrosion? Frankly, any good bolt will do IMO.

Adequate tension in the bolts should lock the sprocket onto the hub, but you might consider drilling the outside of the oval holes round & fitting bushes. Yes check the chain & sprockets for wear & replace as a set if required. Check the chain tension when the 3 axles (F sprocket, swingarm axle, wheel axle) are on 1 straight line, that's when the distance is longest & the chain is tightest (with the chain at the tightest position, if there is any).

I think for about $1000 you found yourself a magnificent bike, congratulations! Enjoy it, but yes, it will need work, older bikes always do.

[Jeremiah31]

Yes i done all of that took it apart checked it out all looked good, i then drove it about 50 miles that night then maybe another 50-60 last couple of days all’s good just need to get new chain and sprockets ASAP cause i agree they look super worn but I’m taking everyone’s advice seriously and fixing things up here and there, going to get all the mechanics worked out before i attempt anything else,
Appreciate all the help y’all are awesome
Thanks!!