gear commander

[mrapriliafalco]

http://www.gearingcommander.com/


Has anyone come across this site,Change the front to 15t set the revs to around 8k and at the bottom the chain and sprocket wear indicator for the front sprocket almost doudles
before you know it an hour has gone playing with this site

[Chabby]

Hmmm.............That would tend to indicate it's better increasing the size of the rear sprocket rather than going down to a 15 on the front to achieve the much recommended Falco gear reduction.

[D-Rider]

,Change the front to 15t set the revs to around 8k and at the bottom the chain and sprocket wear indicator for the front sprocket almost doudles

I seriously doubt that's the case in real life - the change in bend radius and link to link deflection from a 16t to a 15t sprocket is minimal - I did the calculations (they're posted on the forum somewhere)

[mrapriliafalco]

If you increase the rear and leave the front at 16, the same tooth wear is 8 over 21 at 8000 rpm but if you go for the 15/41 the front shoots up to 15/41

[D-Rider]

If you increase the rear and leave the front at 16, the same tooth wear is 8 over 21 at 8000 rpm but if you go for the 15/41 the front shoots up to 15/41

So I think what you are doing here is to gauge increased front sprocket wear based on the number of rotations for a given distance travelled.

Taking the standard 16/41 gearing as a reference:

• Dropping the gearing by increasing the rear sprocket by one tooth (16/42) will give a 2.4% increase in the rotations of the front sprocket
  
  Dropping the gearing by increasing the rear sprocket by two teeth (16/43) will give a 4.6% increase in the rotations of the front sprocket
  
  Dropping the gearing by decreasing the front sprocket by one tooth (15/41) will give a 6.2% increase in the rotations of the front sprocket

The 16/42 gearing is not much different to standard - the 16/43 and 15/41 are worth looking at - and the difference isn't huge

[mrapriliafalco]

I found it interesting, giving you all the speeds etc with the different rev and sprocket combos

[D-Rider]

Yeah - sorry wasn't knocking the site - I know a lot have used it and become very absorbed by it.

[mrapriliafalco]

It amazes me the amount of work put into these free sites

[mangocrazy]

Yes, I've used the gearingcommander site before and it's a very handy tool. My view is that if you can set the gearing to a front/rear ratio that theoretically causes less chain wear, why wouldn't you do it?

I've always been a bit leery of reducing front sprocket sizes, partly as a result of increased bend radius of the chain, partly because of reduced clearance between chain and swingarm, and also because I've heard that it has a marginally adverse affect on suspension (can't prove that, though).

I'm intending to increase my front sprocket to a 17T (standard on RSVs, apparently) and increasing the rear sprocket to a 46T. This should give a ratio somewhere between 16/43 and 16/44, I think.

[mrapriliafalco]

It LIKES a 17/43. I wonder what that would like,My old Falco had the 15 front and standard rear!!! much prefer that to the standard 16

[mangocrazy]

17/43 makes the Falco even more overgeared than standard 16/41. Not really advisable...

[D-Rider]

My view is that if you can set the gearing to a front/rear ratio that theoretically causes less chain wear, why wouldn't you do it?

That's an easy one - Cost!

Unless you are replacing the whole setup then it is cheaper to change your gearing by changing the front sprocket rather than the rear.

Also, it you exactly matched the gearing, the number of turns of the front sprocket for any given distance travelled will be the same irrespective of whether you change the front or rear sprocket.
The marginal difference will be chain wear caused by a small additional deflection due to the slightly smaller bend radius.

[mrapriliafalco]

Stick with another 15 front me thinks

[mangocrazy]

That's an easy one - Cost!

Unless you are replacing the whole setup then it is cheaper to change your gearing by changing the front sprocket rather than the rear.

Yes, I was talking 'ideal world' scenario...

[HowardQ]

Can't see the site at work, but it does remind me of earlier experiences on my side.
When I first decided to lower the gearing on mine, the bike was in for a major service with an Aprilia Dealer who flatly refused to fit a 15T front spocket for two reasons -
1) This would put extra wear on the chain and sprocket as mentioned.
2) It would also leave the chain much too close to the swingarm and be likely to cuse problems here as well.

I argued, he stood firm, so ended up fitting a one tooth larger Mille steel rear sprocket in stead, and kept the standard 16T front.
It was an improvement but hardly a major change, would have needed to go 2 or 3 teeth up on the back to match gearing of a 15T front.
I later went with the simple 15T front mod and it is still the best gearing mod for me even if the chain is then a bit too long and I don't reckon chain or sprocket wear has been any worse.
Lots of people on here have done it and nobody has ever mentioned excess wear or snapped chains.