HELP! Seized front sprocket nut

[Newgolddream]

Nice sunny day, bike out of garage for new chain and sprockets, but I can't budge the front sprocket nut. Will leave it overnight with some penetrating stuff on but any further advice / tips out there?

Need it for work Monday, if it won't move tomorrow will an old sprocket do much damage to the new chain (40 mile round trip)?

Oh, it's an FZ6 Fazer. Previous bike - FZS600 - nut generally came off on it's own!

[Dead Eye]

What are you using to try and remove the old nut? I usually use something to lock the rear wheel in place (metal bar resting on top of the swing arm between the spokes) and use a decent fitting socket with a 750mm breaker bar

As for chain damage... I'm not entirely certain but I guess you already cut off the old one?

[slimwilly]

Yes i had to use a bar to lock the rear wheel too, a long bar,about 4 foot,


Remember to flatten out the tab washer first, and look for a no damage result on the rear wheel, i had to stand on the bar and bounce.


Billy

[Dead Eye]

Wow... that's pretty extreme, I didn't have to apply anywhere near that sort of pressure to get mine off... hell, the original nut is only supposed to be up to 70Nm 

If its that stuck I would almost be tempted to get a garage to do it, that way, if they break something it isn't quite as much of a problem...

[red98]

had the same problem myself a few years age,use an air powered  impact wrench in the end,the type tyre fitters use...probs over tightened due to the horror stories of nuts coming loose 

[Fazerider]

A worn sprocket shouldn't cause a problem for a new chain... at least, not in that distance. (A knackered chain will wear a new sprocket quite fast though.)
As for shifting the nut, screwlock compounds often seem to get tougher with age. I've had to use far more force than I'd expected a couple of times and the "crack" when it finally lets go is quite alarming. If you've a butane torch, heating the nut quickly up to 100ºC should weaken the compound enough to make the job easier.
 

[Lawrence]

I used an impact wrench to get mine off, worked a treat.  That was with  no chain fitted too.

[wannafazer]

Me too with a battery powered impact wrench.

[Newgolddream]

Thanks for the advice guys.

Heat and a breaker bar did the job in the end - looked like it had been thread locked.

All back together and cleaned-up and a nice sunny work commute to today ...... makes a change after all the cold and wet of the last few months.
Looks like the ACF50 did a good job also, just hope I've not washed it off too soon.