urgent..change front sprocket engine in?

[swissdean]

Hi, I;m trying to change front sprocket without removing top end and engine in bike. have in 2nd gear and daughter stamping on the rear brake but i just seem to be winding against the spring with no give in the bolt..bike also sliding along the bench and rear wheel slightly turning at max elbow torque!

any quick tips or tricks out there, hoping to sort out tonight..next plan is clutch plates out and clutch holding tool bolted in place

cant find my impact driver as was planning to give that a go also

thanks

[Warkton Tornado No.1]

I would sooner use an impact gun, too, but as you say....

I can't really recommend this, but have done so myself, so:


Jam something alloy or copper, brass in the chain to clutch sprocket 'nip'

You shouldn't damage anything if the material used is softer than steel.

Gulp!

[MickYork]

bit of a "roadside repair" and not really recommended but !! we jammed a cloth in the chain which jammed everything up nicely....

....................or use a flywheel holding tool

[Donnie]

likely to twist the crank using a flywheel holding tool.

Not sure why your not just using the clutch basket holder, you must have one if you are planning on removing the clutch?

[Wack]

Once you've stopped the chain turning use a good 6 sided socket then take up the spring tension and give the ratchet a sharp jab with the palm of your hand. The shock should break the threads grip, other than that someone has over tightened the bolt in the past. Torque to 25 ft/lb up to 30 on a tuned motor.

[Wack]

Here's something I knocked up to do swift sprocket changes on race motors

[swissdean]

thanks everyone, really swift replies..much appreciated, ...will be trying clutch holding tool now, but really like that last gadget..someone should make and sell those..the 6 sided (and i read elsewhere on here) grinded down socket will be next on my shopping list for future use

[Eden]

Take the clutch out and hold it with the clutch holding tool

[Tractorman]

Here's something I knocked up to do swift sprocket changes on race motors

Excellent!

[Eden]

imo holding with the clutch holding tool is best solution as the sprocket is being held by many teeth by the chain rather than all the force on one tooth.

Nice innovation though, year and years ago I used to fit a socket over a tooth so the chain trapped it and held it. clutch is better though, take 2 mins to take the plates out.

[Wack]

You may be right Eden but if you think about it the load is spread out over two hardened teeth against a piece of mild bar so in theory it's probably better than straining a chain and who wants the hassle of pulling a clutch to pieces just to change a sprocket?

[Scooterlam]

For us "Modernists" using an af clutch you can hold the clutch without dissasemblimg the clutch.
But rubber handle of pliers doez it for me.

[Tractorman]

You may be right Eden but if you think about it the load is spread out over two hardened teeth against a piece of mild bar so in theory it's probably better than straining a chain and who wants the hassle of pulling a clutch to pieces just to change a sprocket?

Plus you are only torqueing up to 25ftlbs.

[jonno]

Piece of rope down plug hole works a treat.

[isthmus]

hi all,just a thought,if you use a longer shaft on your nut you will need less force to undo your nut,just a thought.

[Simon ELC]

Here's something I knocked up to do swift sprocket changes on race motors

Great idea I made something similar for my Dragster.

[swissdean]

clutch out and clutch holding tool it was, a doddle thereafter..btw, I replaced with a Jockey Boxenstop chain guide, with it pushing down and then measured the float/slack at top near the front sprocket..set to between 6m and 8mm, loctited two screws in place...stickys book says 6m is about right ..just interested what others do

[HxPaul]

What we used to do years ago,(and not recomended )is put a screwdriver on the bottom run of the chain and turn sprocket until the screwdriver was trapped between the chain and the bottom of the front sprocket.Fasten on the top run.

[Paulnobodyimportant]

Chain tension OK at 6-8mm.
Anyway, read your thread earlier this week and took note for my re-build. However, yesterday, between other things, I managed to snatch some time to re-build top end ready for air leak check, once all sealent had done its stuff. Stood back to admire my work and my draw dropped.






Clutch plates out next!