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Discussion Starter #1
Hey guys,

My bike needs a bit of TLC at the moment.. Oil, filters, carbs, front pads, brake fluid are all good so just want to clean brake pistons (full of dust), replace dust seals, rear pads and maybe wheel bearings if it isnt too hard.

I know how to take the rear wheel off.. Is it then easy to change the rear sprocket? What about the front sprocket? And is it easy to measure how many links you need to take out of the new chain, and then connect the chain together and put it on?

Also, would I be able to replace the wheel bearings and dust seals myself?

In regards to cleaning brake pistons, do you just undo the caliper bolts, remove the brake pads, spray the pistons with brake cleaner and then just scrub with an old toothbrush??..

Dumb question but I can remove my front calipers (to clean the pistons) without a front stand, right?

Thanks :)
 

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Sprocket change is easy. Just take off the wheel and undo the bolts holding on the sprocket.

Front sprocket is just as easy but make sure that you bend down the tab holding the front sprocket on. Some people seem to have a lot of trouble taking it off as it is on there really tight but I have never had a problem getting it off after i bought the correct size socket bit and put the wrench in a bit of steel pipe for extra leverage and it came off without too much trouble.

Front brake calipers dont need the front wheel to be removed so you dont need a stand but i would reccomend you get one anyway it makes working on the bike easier.
 

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Discussion Starter #4
OK sweet so I can manage the sprockets, what about the dust seals, wheel bearings and chain?

EDIT: I was thinking of going up a few teeth on the rear sprocket, or maybe one down on the front, so I can get a bit more acceleration. Will this effect my speedo and/or fuel efficiency?
 

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I did my chain and sprockets today.
dear. fucking. god.
Hassle and a half with the chain. Guy at the store tells me ill get by just fine with a grinder and centre punch rather than a chain breaker and pliers rather than a press tool to put the clip link on.
HE. LIED.

Sprockets were easy, cutting the single link that was to long on the chain was like wrestling an anaconda on meth, ended up bashing at it for hours trying not to bend it and finally got the pin punched through with the centre punch after filing the top off the rivet.

Getting it together was worse, trying to press the chain together properly with C clamps, the clip went on wrong and then snapped.

Wrestled the old clip off the old chain, slightly mangling it in the process, finally got it on the new chain and its not on right, currently have some thin as fuse wire twisted around that link holding the clip on, limped all the way home and going to have to limp up to the mech tmoz and get them to redo the master link.

Tools make the job, decent chain breaker would make it so much easier, dont know what the fuck your meant to use to press the chian together.
 

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Before you do anything have the bike in gear and loosen the front the sprocket nut, the rest is all pretty straight forward. Chain breakers make the job easy but you could use an angle grinder if you have to. Have a good think before you cut the chain to length, last thing you want to do is cut it short. And yer don't use a clip link, use the rivet link.
 

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I have never struggled with a grinder. I didnt even know what a chain breaker is. Now that i know what one isnt i wouldnt bother getting one. Grinder ftw
 

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+1 - Grinders are fully of sparky fun times!

Chain and sprockets are easy enough to do - the front can be a hastle, but if you forget to loosen it before taking the chain off, just wrap the old chain around it a few times till it locks in place and jams the sprocket. Then with a breaker bar go nuts.

The rear can be a pain as well - loctite is a bitch. But once again the almighty goodness of a breaker bar will save the day!

As for rivet vs. Master clip - on a 250 it won't make a difference. Go with what ever is easier. Rivet's are better and stronger obviously - but it's nothing to worry about on a 250.

Might be worth waiting till the service day to do some of the things, and then people there can actually guide you through how to do the other bits and bobs yourself if there's no chance to do them on the day...
 

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Discussion Starter #11
CBF spending $49-89 on a chain breaker so I'll do it the dodgy way and grind one end off the master link, and then push the pin through with a centre punch or C clamp and a nail or something.

So can anyone confirm the process to replace the sprockets and chain the process would be:
- put bike in gear
- break chain using old rusty tools and dodgy un-proven and not recommended methods
- take front and rear sprockets off (can't be too hard.. just take the nuts off, line the new one up and secure it on. does the sprocket have to go a specific way or can it go either way?)
- put the new sprockets on
- measure the chain
- connect the chain

Am I missing anything?

Questions:
1) How do I measure the new chain? Standard gearing requires 134 links and I'm going up 2 teeth on the rear and usually going up 1 tooth = need 2 more links, so I'll need about 138 links. But obviously I dont want to go solely off this.. I'd rather measure it properly to be sure.. Do I just wrap the chain around the sprockets and hold it in a place as it would be if it was connected, and make sure there is the correct amount of slack in the chain?
I guess I could just count how many links the old chain has and then add 4 links (because I'm going up 2 on the back) but the old chain might be stretched so this count might be unreliable?
2) I've heard the right amount of slack is about 25-40mm but since it's a new chain I'll keep it more towards 25-30mm because if anything it's going to stretch. Sound about right?
3) Took the front sprocket cover off today and there are piles of shit next to the front sprocket and all around the cover.. Is the best way to clean this just to use the compressor to blow as much of it off and then spray degreaser on it and brush it off?..
4) What does that hose connected to the front sprocket cover do?
5) The chain I'm going to buy comes pre-lubed. Should I leave it as is, or lube it with my chain lube as well?..
6) Are wheel bearings and wheel dust seals easy to replace?
7) Is it easy to bleed the brakes and replace brake fluid?

Sorry about the noob questions :)
 

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Discussion Starter #13
Ninexz said:
just make sure you remove the front sprocket before you cut the chain off.
ok, is that to make it more loose or..?
Ninexz said:
Try to keep degreaser away from your new chain, it can deteriorate the o-rings after time.
Yep, I'll clean all that shit off before installing the new sprockets and chain.
Ninexz said:
The hose connected to the front sprocket is your speedo.
ahh ok that makes sense.

Thanks alot for your help mate.
 

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It makes it easier to undo the sprocket bolt when you have the chain on and the bike in gear, otherwise the bolt just spins around with the sprocket.
You might want to find a breaker bar aswell for that nut. Its the trickiest thing i've had to undo so far.
I had the rear wheel moving before that nut came undone and had to end up shoving a plank in between the swingarm and a spoke before I got it off
 

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Discussion Starter #15
ok cheers. A long pipe should do the trick, right?
Does this mean I have to do the front sprocket nut up as tight as it is when I'm taking it off?
 

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Discussion Starter #16
I've taken the sprockets and old chain off and should be getting new stuff tomorrow or Friday.. Is this the right process for putting the new stuff on:
- put the new sprockets on
- feed the chain through and over the front sprocket and loop it over the rear sprocket
- hold the chain together at the bottom as if it was connected, and make sure there is about 25-30mm tension
- connect the chain

Am I missing anything?

Some of my questions were answered and I figured the rest out, but here are two quick things I just want to clear up before I end up doing something stupid :dodgy:

1) I've heard the right amount of slack is about 25-40mm but since it's a new chain I'll keep it more towards 25-30mm because if anything it's going to stretch. Sound about right?
2) The chain I'm going to buy comes pre-lubed. Should I leave it as is, or lube it with my chain lube as well?..


Sorry about the noob questions :)
 

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leave your new chain as is, just clean the OUTSIDE of it when you have everything back together.

remember to have your adjusters ALL the way IN when you put the new chain on.

30mm of play is the optimum amount of play.

oh and you SHOULD be torqueing all your sprocket nuts up to factory spec not to feel, you really should be using a torque wrench.
 

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Discussion Starter #18
Thanks alot for the advice Scotty :D

What about if I just stick the bike in gear and tighten the front sprocket nut up as far as I can with a long pipe (the same way I took it off)? That should be alright shouldn't it?..

OK so put the adjusters all the way in, wrap the chain around the newly installed sprockets, and then how do I measure the chain? Do I just put the adjusters back to where they currently are, and hold the chain where it would be once connected, and make sure it roughly has 25-30mm of movement?..

Stock gearing takes 134 links and I'm going up 2 teeth on the rear so I should need about 138 links but i want to measure it properly?..
 

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yeah sure you can do that, just like i'm sure the manufactures thought the need to release all the factory torque specs for PROPER bike maintenance in order of rider safety was just for shits and giggles.

at the end of the day it's your bike and you can do your maintenance in which ever way you desire.

you measure the chain by placing it on your sprockets and lining up the correct links, if you have your adjusters all the way in then as the chain ages you'll have room to adjust but if you have them all the way out then as your chain ages you will not have any adjustment.

make sure you have both ends of the chain on an outside link, so you may need to move your wheel slightly to make this happen.
 

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I was under the impression it was a bad idea to use a fuckload of force (breakerbar) on the front sprocket with it in gear because it puts unnecessary pressure on the crank? when i did mine a few days ago i chucked it in neutral and jammed the spokes of the rear wheel.
Mind you i was expecting to spend an hour trying to wrestle the nut off, it came flying off with my mates air compressor rattle gun and hit me in the face. >.>
 
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