Rear sprocket upgrade. Whats your opinion

[cbcanada]

I am thinking going up to 43 in the back. I currently have a 40.

Do i need to change the chain length?

Keep in mind that my bike is geared stock 42. The owner prior to me took her down to 40

[stopintime]

See my post on the first page 

[cbcanada]

See my post on the first page 

Bit confused so you recommend the 15/43

But the second part you mention some cons regarding it? Or am i misunderstanding ?

[stopintime]

Bit confused so you recommend the 15/43

But the second part you mention some cons regarding it? Or am i misunderstanding ?

I think changing to a larger rear sprocket, or smaller front, is a good idea as it seem to please most Monster riders.
If you don't like it - go back - which BTW will be cheaper if it's only the front...
The result of 15 to 14 is the same as 40 to 43.

Mods tend to come with secondary results in addition to the intended. Different size sprockets changes the wheel base and the ride height. With the stock 104 links chain - the wheel base becomes ~9 mm shorter - maybe you'll notice, maybe not. Also, with the axle 9 mm forward - the bike will become slightly lower (can be adjusted with the ride height rod). Chain with 106 links will put the axle quite close to the 3 o'clock position, which can make it impossible to tighten after 'a while' and this position also lowers the ride height by ~ 10 mm.

If you think all this axle-, height-, links and adjustments-talk is hard to understand and get under control... I suggest doing a 15 to 14 conversion as a much simpler and cheaper method.

[Rudemouthsky]

I'm at 15/41 on my old 900, and I may go to 14 up front. Depending on how I like the current gearing with the new engine mods. The bike was a dog for many reasons that were no fault of the gearing.

Not that this is a survey or anything...

[koko64]

15/41 on my '95 M900. Very nice compromise.

[cbcanada]

I think changing to a larger rear sprocket, or smaller front, is a good idea as it seem to please most Monster riders.
If you don't like it - go back - which BTW will be cheaper if it's only the front...
The result of 15 to 14 is the same as 40 to 43.

Mods tend to come with secondary results in addition to the intended. Different size sprockets changes the wheel base and the ride height. With the stock 104 links chain - the wheel base becomes ~9 mm shorter - maybe you'll notice, maybe not. Also, with the axle 9 mm forward - the bike will become slightly lower (can be adjusted with the ride height rod). Chain with 106 links will put the axle quite close to the 3 o'clock position, which can make it impossible to tighten after 'a while' and this position also lowers the ride height by ~ 10 mm.

If you think all this axle-, height-, links and adjustments-talk is hard to understand and get under control... I suggest doing a 15 to 14 conversion as a much simpler and cheaper method.

Okay i definately dont want to lower the ride height. If i do the 14t front then i can keep same height? Or is their anyway to do the 43t back without lowering the height and or not being able to possible re adjust chain.

Thanks for the clear up

[stopintime]

Okay i definately dont want to lower the ride height. If i do the 14t front then i can keep same height? Or is their anyway to do the 43t back without lowering the height and or not being able to possible re adjust chain.

Thanks for the clear up

All chain/sprocket mods and new chain lengths affect the axle position - some more than others.
If a mod, or combination of several, makes the bike lower - you can raise it back up with the adjuster rod, but it requires careful measurements and often some swearing and bloody knuckles.

So, a 43 will make the wheelbase shorter and you 'should' adjust the ride height to stock, where it is now or wherever you want it. The same gearing change is achieved with a 14 front - without changing the wheelbase or ride height much at all.

[dbran1949]

I did this a few years ago in excel just to compare ratios sorted by ratio

Front   Rear   Ratio
15   38   2.533
15   39   2.600
15   40   2.667
14   38   2.714
15   41   2.733
14   39   2.786
15   42   2.800
14   40   2.857
15   43   2.867
14   41   2.929
15   44   2.933
15   45   3.000
14   42   3.000
15   46   3.067
14   43   3.071
15   47   3.133
14   44   3.143
15   48   3.200
14   45   3.214
15   49   3.267
14   46   3.286
15   50   3.333
14   47   3.357
14   48   3.429
14   49   3.500
14   50   3.571