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Discussion Starter #1
Had my 2007 F41000R coolant changed to engine ice and while at the dealership they recommended I put a Brutale rear sprocket on my bike. He said it would be two teeth up and much better for the track (less low RPM bogging). Should I do this?
 

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Not sure how the F4 is geared, but going up 2 teeth in the rear will keep your motor higher up in the rev range where it makes more power when you are on the track. It will definitely help on tighter tracks with slow corners. If you are noticing the motor is bogging or lugging when you are the track, then you would benefit from going up a few teeth. If you are experimenting, you'll want to consider changing the front sprocket, as they are cheaper. Dropping 1 tooth in the front is like adding 3 teeth in the rear. There are a lot of formulas to follow, but it will come down how you want your power delivered and at what rpm you are comfortably riding at. Some like using the horsepower at high rpms, and some are comfortable using the torque at lower rpms..on the liter bikes anyways.
 

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Gear your bike so you reach top speed/rpm in top gear at the braking point on the longest straight.

If you haven't got a straight where you can ever get to top speed regardless of gearing then go for the gearing that puts you in the best gear/rpm for the most corners.

Larger rear will lower top speed but then you may find yourself in between gears in a bunch of corners.

Compromise compromise.

Smaller front sprockets have benefit of lower cost and no need for longer chain but also will wear the chain out much faster. Chains like a larger radius to curve around. They also are a large change in ratio where rear sprockets will give you more choices to find the right set up for each track.
 

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Discussion Starter #5 (Edited)
richd748;
go to Keith Code's School.......

bog a 1000R????? you starting in 4th? :wtf::wtf::wtf::wtf:

I feel pretty good were it is (bog is the term the MV dealer used), saying he thought I might get better acceleration out of the corners. I usually run 2nd in the tight corners and up to 4th on longer straights (reaching 120-140's, rpm's stay around 7,000-redline). If you have modified your stock gearing then any input that you think might improve my track performance would be appreciated.
 

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7000 rpm isn't anywhere near red line!! The power is really just about to come on!!! 8~10,000 would be a better range for power delivery.
Since you never use top gear you will find you can run higher gears with closer ratio spacing if you use a larger rear sprocket. That leads to better pull off the corners.

I put the largest rear sprocket I had on my SPR and could go higher still at the tight tracks. As is it is just right at Roebling Road (long front straight) and Barber, still too tall at Little Tally (very short straights), but I would go back down if I run Road Atlanta (very fast track with long back straight).

Your speedometer is inaccurate when you change gearing, but that can be addressed with a calibrator if desired.
 

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Discussion Starter #7 (Edited)
7000 rpm isn't anywhere near red line!! The power is really just about to come on!!! 8~10,000 would be a better range for power delivery.
Since you never use top gear you will find you can run higher gears with closer ratio spacing if you use a larger rear sprocket. That leads to better pull off the corners.

I put the largest rear sprocket I had on my SPR and could go higher still at the tight tracks. As is it is just right at Roebling Road (long front straight) and Barber, still too tall at Little Tally (very short straights), but I would go back down if I run Road Atlanta (very fast track with long back straight).

Your speedometer is inaccurate when you change gearing, but that can be addressed with a calibrator if desired.

I obliviously know 7000 is not redline (it does not read 7=redline). I try to maintain my rpm's between 7000 to redline. Coming into some tight corners it comes down to 7000 or a little lower but 1st gear would not be appropriate. I have been doing track days for a while and at the two main tracks 4th is highest gear on the longest straights. Maybe I will just keep stock gearing for now, going to COTA in September and from what I have been told, I will be using 6th gear on the straights there. I have a one lap video in the "on the track" thread (last page), maybe some feedback from that. Looks like going up two teeth in the back would help keep my 2nd gear RPMs in a better range for my usual tracks.

As far as the speedometer, not concerned about accuracy. Don't pay attention to my speed, but lap times. Only really know the speeds after watching my gopro video.
 

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If you want to change, and I would, go up at least 2 teeth at the back. Take note of your ride height before and after adjusting your chain, it will affect your bike's handling.

If you find a track where a 312R uses 6th in standard trim, show me the video please, that would be fun, the straight would have to be longer than 2km long I recon.
 

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Discussion Starter #9
If you want to change, and I would, go up at least 2 teeth at the back. Take note of your ride height before and after adjusting your chain, it will affect your bike's handling.

If you find a track where a 312R uses 6th in standard trim, show me the video please, that would be fun, the straight would have to be longer than 2km long I recon.

Thanks for the input/advice, with past questions also. Going to go ahead and change out the back sprocket.

I saw you had the shift indicator in the "on the track" pics, how hard is it to install, is it essentially plug and play? I would like to order one.
 

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I saw you had the shift indicator in the "on the track" pics, how hard is it to install, is it essentially plug and play? I would like to order one.
Very easy to install, plugs right in behind the dash.
The latest one (Gear-tech) I have is a bitch to do the actual shift light set-up, but the gear selection set-up was easy enough.
The Accumen is easy to set-up but no shift light option.
http://www.designcorse.com/shop/mv-agusta-parts/mv-agusta-f4-parts/mv-agusta-f4-750-1000-312-1078rr/mv-agusta-f4-gear-indicators
 

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Donsy I'm currently looking at a standalone shift light set. The F3 is so hard to see and I want to set mine at about 11,5 when the bike is making peak numbers. I've seen a few online but are kind of clunky looking.
 

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I obliviously know 7000 is not redline (it does not read 7=redline). I try to maintain my rpm's between 7000 to redline. Coming into some tight corners it comes down to 7000 or a little lower but 1st gear would not be appropriate.
My bad, I interpreted that as riding mostly around 7k...not 7k+....sometimes I'm a bit slow in the thought process.. :nerd:

Regardless, the advice on selecting gearing is the same.

COTA has a straight where the MotoGP boys routinely go well over 200+ mph. That track looks to be a fun and very fast ride. Wish I could join you..
:f4:
 

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Discussion Starter #13
My bad, I interpreted that as riding mostly around 7k...not 7k+....sometimes I'm a bit slow in the thought process.. :nerd:

Regardless, the advice on selecting gearing is the same.

COTA has a straight where the MotoGP boys routinely go well over 200+ mph. That track looks to be a fun and very fast ride. Wish I could join you..
:f4:
I will definately post some GoPro video from COTA.
 

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Discussion Starter #14
I was going to go up 2 teeth on the rear for my 2007 F4, dealer has a 43T brutale sprocket which he thought was 2 teeth up. Realized this is actually 3T change. What do you think about going up this much, next track day is next weekend and I could get it done quick since it is in stock. The two tracks I mainly run are 2.5 and 1.7 miles, usually only get to 4th gear on the straights. Don't want to turn it into a wheelie machine. Would you recommend I just order a 42T?
 

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I was going to go up 2 teeth on the rear for my 2007 F4, dealer has a 43T brutale sprocket which he thought was 2 teeth up. Realized this is actually 3T change. What do you think about going up this much, next track day is next weekend and I could get it done quick since it is in stock. The two tracks I mainly run are 2.5 and 1.7 miles, usually only get to 4th gear on the straights. Don't want to turn it into a wheelie machine. Would you recommend I just order a 42T?
Go for it! 3 in the rear is (very) roughly -1 in front. It's a good change but not too big.
 
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