How can i tell if a sprockets worn?

mrbluesbox · Scooby Slapper Joined: 14 Sep 2006 Karma :

Hi all

apart from the obvious (like missing teeth) how can i tell if a sprocket is worn enough to need replacing, i went to get my chain replaced ealier today and the guy said the sprockets needed to be changed too - only thing is i got a quote for £130 + vat for new sprockets so would really like to check it myself before forking out all that cash.

Thanks

Gaz.
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I seem to have misplaced my pants...................

puremagic72 · Brolly Dolly Joined: 15 Nov 2005 Karma :

You should really change the sprockets the same time as the chain anyhow, but usually they have rounded off sleightly, look at the sprocket facing down towards the chain, and see how far the teeth are in there.

Baz. Thumbs Up

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Gsxr 750 2000, alstare Corona, Current bike 1999 R6
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phantomtek · Lil Joe Tek Joined: 20 May 2005 Karma :

Basically, if the teeth don't look like they can hold the chain on and turn it then they are excessively worn, they should be more rounded triangle shaped than circular.

Should look like this:

https://www.motoworldracing.com/media/Renthal/renthal-05-FrontSprocket.jpg

Not this:

https://www.bmwmotorrad.co.za/bikes/bikeEval/pix/evaluation19.jpg

Or excessively worn.

irving · Traffic Copper Joined: 02 Oct 2006 Karma :

Finglonga · World Chat Champion Joined: 27 Jul 2004 Karma :

Feck me!!!! £130+vat for sprockets for a derby GPR 125 I would go somewhere else, how much did hthey charge for a chain? They are ripping you off. PLUS if they were any good they wouldn't supply just fit a chain they would tell you that you need both, as a new chain on old sprockets wont last long.
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irving · Traffic Copper Joined: 02 Oct 2006 Karma :

Zimbo · World Chat Champion Joined: 09 Jul 2004 Karma :

irving · Traffic Copper Joined: 02 Oct 2006 Karma :

veeeffarr · Super Spammer Joined: 22 Jul 2004 Karma :

Throw it up in the air and nut it as it comes back down.

If you don't hear the thud of it hitting the floor 2 seconds afterwards, you need a new one.

And possibly a doctor.

mrbluesbox · Scooby Slapper Joined: 14 Sep 2006 Karma :

Cheers.

Had a quick look at the rear today and compared it to the pics and i suppose it does look like its a little worn.
Been having a look round on the net and parts are a bit scarce for the GPR 125 Nude - theres loads for teh 50cc version but feck all for the 125.
Those quotes for the sporckets were from fowlers.co.uk derbis main parts dealer, so didnt even include fitting or the chain Shocked

.
Found em a little bit cheaper at bike-spares.co.uk but theyre still around 40 quid each.
Does anyone know of anywhere id be able to get them cheaper?
Also what does anyone think about patterned sprockets and do ya know where i could get any?

Thanks

Gaz.
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I seem to have misplaced my pants...................

Kickstart · The Oracle Joined: 04 Feb 2002 Karma :

Hi

Cheapest places I have generally found for C&S is either Trade Direct or Busters.

I would have no issues using non original sprockets. Tend to shy away from alloy sprockets though.

For comparison I think I paid £42 for the last C&S for my RS125 (520 chain).

All the best

Keith
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0ddball · World Chat Champion Joined: 15 Jul 2005 Karma :

They are ripping you off, plain and simple.You should be looking at around £100 for new sprockets and a chain supplied and fitted.

Try one of the companies Keith sugested and you'll get a good quality chain with new steel sprockets for around £60. Then find a decent bike shop to fit it. Even the most expensive shop in my area (Powersport) only charge £45.

irving · Traffic Copper Joined: 02 Oct 2006 Karma :

0ddball · World Chat Champion Joined: 15 Jul 2005 Karma :

As i said, £45 (yes fixed price and inclusive of vat) is the most expensive shop in the area, some will do it for £30 so i'm sure it's possible to find a someone reliable to do it for £50 pretty much anywhere in the country. Any professional outfit that can't fit a chain and a pair of sprockets in an hour need to seriously look at how many tea breaks their staff are having.

irving · Traffic Copper Joined: 02 Oct 2006 Karma :

0ddball · World Chat Champion Joined: 15 Jul 2005 Karma :

Well i'm obviously in the presence of someone who's been there, done it, got the T shirt ect so i'll take your word for it.

I don't have anything to do with main dealers anyway as i refuse to pay a mechanic, sorry 'technician' £50/hour to tighten a few bolts.

Vincent · Banned Joined: 16 Oct 2006 Karma :

Whereabouts are you Question

There must be someone on the forum that could give you a hand fitting new C&S, that way you can learn how to do it yerself next time Wink

irving · Traffic Copper Joined: 02 Oct 2006 Karma :

mrbluesbox · Scooby Slapper Joined: 14 Sep 2006 Karma :

Thanks for all the replies on this.
Tried contacting all the mentioned companies but had no joy getting any patterned sprockets.
Eventually managed to get a front sprocket and chaing from www.bandcexpress.co.uk for £27 delivered, and im ordering the original derbi rear for £52 + delivery from www.bike-spares.co.uk so at least ive managed to save a few quid Smile

Might even have a crack at fitting it myself if it dont look like too much trouble so be prepared for a "i messed up chainging my chain" thread Smile

Gaz
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I seem to have misplaced my pants...................