Riding home tonight from the the fiancee's house my front sprocket flew off Luckily was going slowly on a round-a-bout. Pulled on to hard shoulder. Then for the first time in my life realised I'd left my phone with my missus Walked to a nearby house and got my dad and uncle to bring a van. So glad Ive got the old girl home. Any way nut came loose and the sprocket fell off. I needed a new chain any how so Im gonna treat her to new chain and sprockets Any one got an idea how much they could cost?

Chain & sprockets for a 125, maybe £60-70? I'd want to know how/why the nut just came loose (in case the same fault occurs)

The washer wasn't bent over the nut Vibrated loose.

Just ordered the parts and its £73 for front and back sprockets, nut, washer and a gasket for my exhaust

No new chain as well? I'd check the condition of the chain carefully before putting the old chain on with new sprockets!

I'd have a shop around.
I only paid £110.00 for chain and sprockets for my Bandit fitted, and have been quoted about the same for the Daytona.

Oh yeah and a chain. I forgot BG. I definitely need new chain its on the last 2 notches. But best to get new sprockets all round too cos old ones can make a new chain go funny. 955i I think thats a good price for all them parts and they are genuine hyosung parts. I always do my own work on the bike. Can't see the point getting some one else to do it. Besides with me doing it and my dad watching over my shoulder I know the jobs been done right

No probs, just thought it sounded expensive if the chain wasn't included.

I agree!

nope youve lost me there.......bent washer?????

The washer for the front sprocket is often a "lock washer". They typically have a few tangs which are bent back against the flats of the sprocket nut to stop it undoing.

Sounds like you didn't lose control or anything Mikeymc, that was pretty good fortune I reckon!

ahhh....it all becomes clear now....thanks for that mate.

This illustrates it quite well:



Top right is the "old-style" lock washer as used on the Triumph Thunderbird, note the tabs which get bent back against the nut. They stopped doing those, however in favour of the bottom right picture - the washer's bent so that it acts as a "spring" putting pressure on the nut to stop it rotating.

Fortunately I was only doing about 10mph round a roundabout. I just suddenly lost power. Coasted it to the hard shoulder, well with a few pushes from my legs The most annoying thing was I forgot my phone. And I still haven't bothered to write down my recovery service number to keep with me

Got all the new bits put on yesterday. Exhuast sounds alot better. But acceleration is alot better cos of chain and sprockets. It seems to have less lag too. Very glad Ive done it. Now we just wait for it all to fall apart