Rear sprocket bolts sheared off!!!

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fredskidoo
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Rear sprocket bolts sheared off!!!

Post by fredskidoo »

Can you believe this!!!

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Observe the wear from the sprocket bolts incurred on the swingarm

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And the ovalized bolt holes from, apparently, a long process of loosening
and, ultimately, shearing of the five sprocket bolts

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Funny (not!) - in hindsight all I recall noticing was a bit of jerkyness during sudden accelerations and hard downshifts - What brought this problem to my attention was a local kid (about 10 years old) noticed, as I was backing my bike out of a parking space in front of the general store a block away from my house for a long Saturday ride, that a bolt had just fallen off me bike - mind you, it was the LAST bolt!!!

All I can say is Thank You, Thank You, Thank You to whom or what ever spared me that day . . .
'87 750 Paso 751412
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paso750
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Re: Rear sprocket bolts sheared off!!!

Post by paso750 »

ouch, that must be the reason why I`ve seen one or two bikes with safety wire through all sprocket bolts.
The swingarm can be welded but luckily it`s one of the parts, like the 16" wheels that appear on ebay cheap once in a while.

G.
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Re: Rear sprocket bolts sheared off!!!

Post by Desmo_Demon »

Like Gerhard stated, you can weld the swingarm and the wheels are readily available. You can also have those hole drilled out and have Helicoils installed. I think I have a spare swingarm and rear wheel and sprocket carrier assembly if you need those parts.

With these V-Twins, you have to watch out for bolts where Lock-tite is not used. I generally use blue Lock-tite on a lot of the bolts on my bikes.
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jcslocum
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Re: Rear sprocket bolts sheared off!!!

Post by jcslocum »

WOW that is FUGLY!!

Weld the arm and heli-coil the bolt holes and you will be good as new!
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fredskidoo
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Re: Rear sprocket bolts sheared off!!!

Post by fredskidoo »

Well, in typical gearhead behavior, I already had another swingarm AND complete wheel assembly just lying around - go figure :thumbup: and now I've got a good reason to take the old swingarm and modify it for the 17" Katana wheel set I also have sitting in a box waiting patiently for the inevitable conversion.

Also, the 5 rear sprocket bolts had the standard nylon lock nuts.
So on that note - don't be too confident when using them to secure
crucial bolts - as Terry said - Locktight is prudent.
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paso750
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Re: Rear sprocket bolts sheared off!!!

Post by paso750 »

inevitable conversion
there is no such thing as long as there are 16" alternatives, although they also require some mods ... :)

G.
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Re: Rear sprocket bolts sheared off!!!

Post by Tamburinifan »

Can you believe this!!!
Almost not, damn lucky you are. :shock:

What´s the reason f this, a spacer missing or w wrong side out or what?!?
Gert

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Re: Rear sprocket bolts sheared off!!!

Post by ducinthebay »

On this account, the Paso is a better design than the Sport. When this happens to the Sport, the swingarm is ruined, and can not be repaired. Both of the Sports I own have modified swingarms, probably due to an episode like this. (One for sure, the other I don't know)

Seems like a good maintenance item when you have the wheel off.

If you are short of parts, drop me a line. I live 50 miles south of you, and have 2 Oscam rear wheels that will never get ridden by me, as I have converted to 17".

Cheers,
Phil
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fredskidoo
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Re: Rear sprocket bolts sheared off!!!

Post by fredskidoo »

If you are short of parts, drop me a line. I live 50 miles south of you, and have 2 Oscam rear wheels that will never get ridden by me, as I have converted to 17".
Hey Phil - Are your Oscams white by any chance?

Ethan a.k.a Fredskidoo
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ducinthebay
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Re: Rear sprocket bolts sheared off!!!

Post by ducinthebay »

Ethan,
No, both of my wheels are RED.

Phil
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Re: Rear sprocket bolts sheared off!!!

Post by Mc tool »

seeing is believing , bit apart from that I would not have believed that anyone could have ridden that (poor ) bike far enough to do such damage and NOT KNOW. ( cant find an arse kick smilie )
This may sound a bit off the mark to start with , BUT , you need to spend more time cleaning your bike , be fussy ,this way you get to know what is what and where it should be . After a bit of this therapy you begin to know your bike and anything out of place becomes very apparent.
Every time I change the oil ( 3000 to 5000 km's ) I go over the whole thing , especially the suspension , brakes and any mounting bolts , footpegs , chain and sprockets, only takes 5 mins. Nylok nuts should only be used once , and for really critical stuff I prefer....... shit ! I cant remember what they are called but they look like normal nuts except the holes are oval shaped so that when you thread them on to the bolt the hole is deformed back to round , again use only once .
I no longer carry tools with me when I ride , not because Im so conceited that I think I wont ever need them , but because I got sick of haveing to lend them to people who seem to think that basic maintainance should be done on the side of the road in the middle of @#&^ing nowhere
I wish I was young again............Id be heaps smarter than last time
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Re: Rear sprocket bolts sheared off!!!

Post by fasterdammit »

So glad I bought that safety wire kit. Who says it's only for track bikes?

Talk about lucky, having that little kid spot the bolt and mention it. Glad it didn't happen at speed. That would've been ugly ... :dunno:
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Re: Rear sprocket bolts sheared off!!!

Post by englishstiv »

I had a Garage change the rear tire for me on my old 600 Monster and they replaced the sprocket spacer back to front I never gave it a second thought until an immediate and fast motorway 120 miles later I pulled off to answer an annoying buzzing mobile in my jeans pocket when I finished and started off the rear wheel seized up as I pulled away. I cursed the Garage for tightening the rear wheel so badly and loosened the rear wheel nut and turned around to limp home only to hear the clack clack of the sprocket nut heads chipping into the swing arm :banghead: I then realised the spacer was incorrectly fitted.

Are you sure that the spacer if fitted was the right way around to start with on yours? I know my 907 has the same spacer fitted.
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fredskidoo
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Re: Rear sprocket bolts sheared off!!!

Post by fredskidoo »

englishstiv wrote: Are you sure that the spacer if fitted was the right way around to start with on yours? I know my 907 has the same spacer fitted.
Alas - mystery it remains . . . I replaced said worn parts and moved on - BUT two days ago the front sprocket clip wore through and the sprocket slipped off. The rear sprocket spacer question comes to mind.Could it cause sprocket/chain misalignment? Last year I had put several hundred miles on the bike before finding one of the rear spacers in my parts bucket.
I promptly rejoined the part to the bike. I suspect that after replacing both sprockets and the chain and not using locktite and reusing the nylon nuts things worked themselves loose.
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Re: Rear sprocket bolts sheared off!!!

Post by Mc tool »

" Alas the mistery remains " :roll: ......... I think that whoever is responcible for routine maintainance on your bike aint doing his bit . I dont mean to get in your face , but please give your bike a real good once over . If you are not mechanically minded , get a knowledgable friend to help out. Maybe I have got this wrong , and if I have I apollogise :oops: , but I would rather run the risk of offending you than to hear that something else has fallen off or failed and you have been injured ( or worse )as a result.
Englishstiv, what spacer are you talking about here ? My sprocket bolts straight to the cush drive .... no spacer. Is it one on the axle ?
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Last edited by Mc tool on Sat Apr 10, 2010 1:14 am, edited 1 time in total.
I wish I was young again............Id be heaps smarter than last time
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