I'm planning to replace my chain & sprockets but undecided as to which route to go. I had a 520 conversion with a -1 front sprocket on my F3 and it was a big improvementover stock. It was also carb'd vs. EFI(helped eliminate/hide this flat spot it had off idle) and I don't think was geared as nicely as the F4i is from the factory. I don't do much highway cruising on this bike so not too worried about the higher RPM's and although I'm not a big wheelie guy either, it would certainly make it quite easy to pop up the front. Anyone gone down on the front? Happy or unhappy with the results?

 

I've got a 525 with +2 in the back, it's a noticible difference and I dig it.

 

first off...i'd go with DID chain...nothing DID...
second...forget the 520 conversion...even on your F3, it wasn't the 520 that you were feeling the umph from but rather the -1.
i had -1 up front...it was great...i now have +3 in the rear instead of the -1...rides pretty much the same as -1 up front. i did the 520 conversion cause the bike will no longer see the streets...and couldn't feel a difference from that.

many go -1 +2...but too me that's too buzzy.

 

my suggestion:
RK chain, Vortex sprockets...
525
-0,+2

 

"first off...i'd go with DID chain...nothing DID... ", are you saying go with or don't go with DID? I know there's no difference regarding the 520 kit, it just happened to be the better deal at the time.
"RK chain, Vortex sprockets" is what I had on my F3.
Does anyone know the comparison of going down 1 up front vs. going up 1, 2, or 3 in the rear? Meaning, is +3 the equivilant to -1? Just thinking that I could maybe go +2 in the rear instead and it wouldn't be as aggressive as going down in the front.

 

i meant nothing BUT DID...
yes...-1 up front is about +3 in the rear...
many riders i know have had bad experience with RK...
woody uses RK though...so he must've had better luck than us.

 

+1 on using DID...I stretched my RK chain to death in only a few months... I've heard good things about EK and Tsubaki chains as well...

Iwas told the only difference in going +3 in the backis that your spedo wouldn't be off as much as it would beby going-1 in the front... not sure how true that is but it seemed to make sense at the time...

 

You're speedo error changes by how much change gear ratios not whether you do the front or rear. To illustrate this:

suppose you have a stock gearing of 16/43. Going -1/0 will give you a speedo error of 6.67%. Going 0/+3 will give you a speedo error of 6.98%. In this case, going -1 has less speedo error than going +3.

Now suppose you have a stock gearing of 16/45. Going -1/0 will give you a speedo error of 6.67%. Going 0/+3 will give you a speedo error of 6.67%. In this case, going -1 has the same speedo error as going +3.

Now suppose you have a stock gearing of 16/48. Going -1/0 will give you a speedo error of 6.67%. Going 0/+3 will give you a speedo error of 6.25%. In this case, going -1 has morespeedo error than going +3.

[if you wish to do the math, all formulas shown here]


Anyway, this clearly shows that its not whether you do the front or rear that determines how much speedo error you get.