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Discussion Starter · #1 ·
I need to replace my chain and sprocket.

I cannot decide.
Do I go for OEM sprockets, and a standard DID standard X-ring chain? £65

Or do I go for the Renthal racing kit? £123
-1 front tooth, and +1 rear tooth.
This would drop my theoretical top speed from 140mph to 127mph.
More importantly... my motorway cruising speed would rise from 8krpm to 9krpm.
BUT it would offer better acceleration, making pulling off more fun, and wheelies more easy.
The Renthal sprockets also look much nicer, and will probably help the chain last a bit longer...

realistically, I SHOULDN'T need my bikes top speed anyway...
And the acceleration is MUCH more fun.

What do you think?
 

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I would go with the Renthal kit as 127 is still a respectable top speed that your unlikely to hit realistically very often.

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Discussion Starter · #4 ·
I would go with the Renthal kit as 127 is still a respectable top speed that your unlikely to hit realistically very often.

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I's not just the top speed reduce. It means cruising at a higher RPM which will mean more fuel consumption, more noise, and more wear on the engine. Don't know realistically how noticeable this would be though.

Also, the increased cost of the kit... although, if it lasts longer, then perhaps it's justifiable?
Otherwise, I can get the cheaper sprockets changed to match...

Gah, it's a tough choice!
 

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Discussion Starter · #5 ·
Do you go over 100 often?

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As much as I would hate to admit to it...

The ammount of late night commuting I do on silent, empty, dead straight A roads...
 
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Fisher said:
I's not just the top speed reduce. It means cruising at a higher RPM which will mean more fuel consumption, more noise, and more wear on the engine. Don't know realistically how noticeable this would be though.

Also, the increased cost of the kit... although, if it lasts longer, then perhaps it's justifiable?
Otherwise, I can get the cheaper sprockets changed to match...

Gah, it's a tough choice!
Maybe get the cheaper 127 size sprockets and if fuel consumption not to much more you know for next time.

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Discussion Starter · #8 ·
Maybe get the cheaper 127 size sprockets and if fuel consumption not to much more you know for next time.

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Hmmm... perhaps a good idea. May just try that...

End of the day, in a £65 kit, I reckon the majority of the cost will be the chain!
So a single new sprocket, be it front or rear, shouldn't cost a whole lot more to buy should I wish to revert back...
 

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Discussion Starter · #10 ·
just keep the bike stock and enjoy it the way it is until you upgrade
I'm hardly changing it from stock...
Sprockets are a common change that people make...

Some people have different uses for the power.

I don't know... I do LOVE fast acceleration!
AND, the new gear ratio will help with riding two up which I do a lot!
 

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Fisher said:
I'm hardly changing it from stock...
Sprockets are a common change that people make...

Some people have different uses for the power.

I don't know... I do LOVE fast acceleration!
AND, the new gear ratio will help with riding two up which I do a lot!
Then I think you know what to do then Cam.

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Discussion Starter · #12 ·
Then I think you know what to do then Cam.

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Haha shhh.... I know what my heart is saying, but my head is trying to persuade it otherwise ^^
 

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Discussion Starter · #18 ·
I WANa change my front sprocket, does that mean in am going to have to change the linking thing too? Or can I just slacken it loads???
Generally... on a 125, you really don't want to mess with the gearing.
You can boost the acceleration, but you WILL loose precious top end!

But if you really wanted, then it's easy enough to do. Just change the sprocket, nout else to it!
No need to adjust your chain usually... if you did, it would be barely any at all really.
 

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Slightly off topic (maybe?) but what MPG do you get at the moment fisher? (On a combined cycle)
 

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Interesting conundrum, I'm toying along the same lines, but more for track day and b-road scratching usage. Three figures are very easy to see and regularly, as for mpg not a consideration as my bike is a toy. I would start at +1 on the rear and leave the front alone for now, and see how you get on with that. As the front is steel and won't wear as fast, so you could try the -1 on the front at a little bit later date.
 
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