The Big Picture on Sprocket Changes

Aug 2012
1,458
850
California
I took my bike through the canyons today Highway 33 in Ojai CA with lots of twisties to see how the 15T/41T would perform and all I can say is WOW. Power coming out of the turns is unbelievable compared to the 39T. I think today is the fastest time I have ever made it to the top. The bike was unbelievably smooth it felt like a totally different bike. Mainly there was no lag in waiting for the RPM to spin up to get some power. The power was just there all through the mid range. Even coming out of the slower hairpin turns the power was really accessible. Finally when we reached HWY 166 there is a long safe stretch to open it wide open. Had my GPS this time and also GPS on my contour2 and GPS with Rlink confirmed it at 191 MPH before she decided not pull anymore. The fastest Ive done with the 39T was 196. I thought it was going to be around 7 MPH slower but it was just 5MPH. Thinking it has to do with more weight savings on the bike or I lost 10 lbs since I last tested Top end.:) In summary I think for me the AFAM 520 light weight Conversion 15T/41T is the perfect set up. I'll give up 5MPH on top end because I rarely see it not even on a track around Southern Cal. I think the 15T/41T accelerate faster to top end. When I get bored with the Pani (which I highly doubt) i will swap back to 15/39 for a while then back to the 15/41 because they really do make you feel like you are riding a different bike.
 
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Jun 2012
5,014
1,152
St. Louis
I took my bike through the canyons today Highway 33 in Ojai CA with lots of twisties to see how the 15T/41T would perform and all I can say is WOW. Power coming out of the turns is unbelievable compared to the 39T. I think today is the fastest time I have ever made it to the top. The bike was unbelievably smooth it felt like a totally different bike. Mainly there was no lag in waiting for the RPM to spin up to get some power. The power was just there all through the mid range. Even coming out of the slower hairpin turns the power was really accessible. Finally when we reached HWY 166 there is a long safe stretch to open it wide open. Had my GPS this time and also GPS on my contour2 and GPS with Rlink confirmed it at 191 MPH before she decided not pull anymore. The fastest Ive done with the 39T was 196. I thought it was going to be around 7 MPH slower but it was just 5MPH. Thinking it has to do with more weight savings on the bike or I lost 10 lbs since I last tested Top end.:) In summary I think for me the AFAM 520 light weight Conversion 15T/41T is the perfect set up. I'll give up 5MPH on top end because I rarely see it not even on a track around Southern Cal. I think the 15T/41T accelerate faster to top end. When I get bored with the Pani (which I highly doubt) i will swap back to 15/39 for a while then back to the 15/41 because they really do make you feel like you are riding a different bike.
+1!
 
Feb 2013
118
15
Plano, TX
I took my bike through the canyons today Highway 33 in Ojai CA with lots of twisties to see how the 15T/41T would perform and all I can say is WOW. Power coming out of the turns is unbelievable compared to the 39T. I think today is the fastest time I have ever made it to the top. The bike was unbelievably smooth it felt like a totally different bike. Mainly there was no lag in waiting for the RPM to spin up to get some power. The power was just there all through the mid range. Even coming out of the slower hairpin turns the power was really accessible. Finally when we reached HWY 166 there is a long safe stretch to open it wide open. Had my GPS this time and also GPS on my contour2 and GPS with Rlink confirmed it at 191 MPH before she decided not pull anymore. The fastest Ive done with the 39T was 196. I thought it was going to be around 7 MPH slower but it was just 5MPH. Thinking it has to do with more weight savings on the bike or I lost 10 lbs since I last tested Top end.:) In summary I think for me the AFAM 520 light weight Conversion 15T/41T is the perfect set up. I'll give up 5MPH on top end because I rarely see it not even on a track around Southern Cal. I think the 15T/41T accelerate faster to top end. When I get bored with the Pani (which I highly doubt) i will swap back to 15/39 for a while then back to the 15/41 because they really do make you feel like you are riding a different bike.
Thanks for the review on your gearing...I wasn't going to do this, but now am seriously considering doing it!:eek:
 
Mar 2013
23
10
N/A
Chain Tension 15/41 set-up

Tech tip: On my R the recommended chain tension for the 15/41 set-up is 47-49mm.
I understand that this slightly tighter than the standard 15/39 tension (50-52mm), not a big difference, but probably there for a good reason.
 
May 2012
551
79
Philippines
I'm running a 15/41 set up too. Installed a longer gold DID chain. I'm using a PBR brand rear sprocket which I purchased locally. PBR sprockets are made in Italy. Thank God there is a local distributor here. Good quality sprockets!!!:)

Anyways, I do a lot of track time and usually take my bike out on sunday blasts on nice twisties roads with my riding buddies.

I am planning on going 42T on the rear and do away with the 41T. Though, the 41T rear has improved my low down quirkyness and improved my mid all the way to a good top end pull...very happy with this present set-up!!:D
I plan to go one tooth up...42T this time as our racetracks here seem to be more suited for a 42T rear sprocket ratio gearing.

My question is:

Since I have gone up from a 39T to a 41T = from a 104 link stock chain to a new 106 link gold chain...DO I HAVE TO REPLACE MY CHAIN AGAIN GOING UP 1 TOOTH MORE FROM 41T TO A 42T?


Any advise will be greatly appreciated.

Miguel
 
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Stw

Former Staff
Aug 2012
6,381
2,530
Dallas.Tx
Had my first real chance today to try out this new gearing... Around town its definitely more livable in Sport mode..But that's not why I did it... Outta town on those of so cool country roads I wanted more oomph... I have to say I most certainly got it... This bike goes like stink now... especially in those 3rd/4th gear pulls out of a faster sweeper.. It puts the bike "on the cam" much easier and quicker and I felt like it was just much livelier.. Bike has around 5k miles now and the engine is loosening up now too...
The other cool thing is when cruising home at a steady 85/90 mph it hasn't lost that nice loping gate it has at those speeds...... so its not lost anything and gained a lot...

I would highly recommend it....
 
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