Help, cant undofront sprocket

Hi guys

Trying to do the simple task of changing the chain and sprockets on the sv. Ive knocked bak the tab, put the bike in gear, and got a mate holdin on the brake. Even with a 3ft bar on it it wont budge!!! Im turning the back wheel with the brake on!!

Ive tried different gears and also claping the chain with a pin through it so it couldnt move and ive bent the pin i was using. Im trying to turn the nut anticlockwise to undo, im 99.9% sure its not a lefty

Any ideas would be much appreciated

[stormingjoe]

If you have a jack handle or other suitable bar long enough, put it through the wheel above swing arm, turn wheel till the spoke rests on the handle then undo the nut, put under swingarm when re-tightening nut.

[Luckypants]

As above but use a bit of wood, its less likely to mark the swing arm. Wrap the swing arm or bar/wood in rags to further cushion it if you want no marks.

[timwilky]

Originally Posted by Luckypants

As above but use a bit of wood, its less likely to mark the swing arm. Wrap the swing arm or bar/wood in rags to further cushion it if you want no marks.

+1, what he said about wrapping it to form a cushion, although I use a small length of scaffold tube

[NTECUK]

Electric impact gun. They do one for about£80 at machine mart.
Really handy bit of Kit.

[TamSV]

And just to confirm, you're right, it's a regular thread - anti-clockwise to remove.

[_Stretchie_]

If you haven't got an inpact gun (electric or air), try an impact driver about £10 from Halfords, or try and heat the nut, I have a butane blow lamp from some B&Q type place for about £15-£20

Like this one
http://www.google.co.uk/products/cat...ed=0CGUQ8wIwAA#

You don't have to get it glowing or anything, just get it heated up and hopefully that will free it up

Cheers for all the tips guys, tried the bit of wood (2x1) wedged in wheel and snapped it before it moved! So used a bit of ally bar and ended up using a scafold pole (6ft) to get it to move. Never have a seen one that tight, it was a struggle with the pole on it.

Done now and shiney sprockets and gold chsin fitted

Cheers

[yorkie_chris]

I've had to grind one off before when the wheel crunched a 3x2 even with my ginger mate stood on the brake!

[mikerj]

Originally Posted by _Stretchie_

If you haven't got an inpact gun (electric or air), try an impact driver about £10 from Halfords, or try and heat the nut, I have a butane blow lamp from some B&Q type place for about £15-£20

There is an oil seal right behind the sprocket, not a good idea to get any heat in this area.