43T Rear Sprocket Mod--A Quiet Upgrade
 

I wanted a little more power in the low end of the bike but not enough to install a 13T front sprocket. That meant that I would need to work with the rear sprocket.

A day or two before Marcelino's cam mod hit the forum, I had ordered a 43T rear sprocket for just a touch of pep for my 250 over the stock 42T. This is the link I had stumbled across for the upgrade from the ancient days of 2006: https://www.kawasakiforums.com/forum...sprocket-5638/.

I'm always on the hunt to pick up a hamster of power here, a hamster there, etc (this is a 250, after all). Now that the cam mod is applied, tested, and accepted, I went ahead and installed the 43T sprocket. Patience is important when doing mods, so as much as I wanted to install the sprocket, I waited a bit until the cam mod proved itself. As I figured, it is noticeable but won't give you whiplash when accelerating from an intersection or out on the highway.

A little top end is sacrificed but not so much that it matters. Note also that the stock length 106 link chain can be used but for me it is on the forward-most alignment notches.

Any thoughts?

Hey Kansas, I did the same, 43 tooth rear, same chain, its okay to have it on the front-most position, will wheelie better and stiffen the suspension a tad with the smaller wheelbase (one inch smaller). I tried it with a non oring chain, what a mess.. went with the stock chain, works perfectly so far.

Good to see that someone else has also taken this path. Perhaps it's a case of great minds thinking alike. :D

From technical curiousity, what was up with the non o-ring vs the o-ring chain situation? I'm still relatively new to the motorcycle scene and while I know what the physical difference between the two is, I can't envision what any difficulties would be for non o-ring in the 43T case, other than maybe a need for more aggressive cleaning/lubing schedule.

it was a cheap chain from the dealer.. full of rust the first time out, and chain slap for the first time.. i like how o-ring chains dont chatter or slap

An O ring chain will last at least twice as long, and when you consider that each time you get a new chain you also need both sprockets you can see how in the long run it is really cheaper and I have found them to need alot less adjustment.

My buddy has a D.I.D O-ring chain and he told me that he's put over 7,000 miles on it and it's not stretched at all. Never had to tighten it.

One tooth on the rear sprocket is not very much, about the same as wearing 1/4 inch off your rear knobby.

I understand what you're saying but I really don't want to wait until the rear tire wears enough to feel a touch more throttle response, hence the 43T upgrade. Just think how it'll feel with both tire wear and 43T! :D

43 tooth rear sprocket put my gear ratio back to stock because I am using dunlop 606 rear which is a taller tire :D

The 606 tire, especially the 130, which is what I have, is probably too big. Maybe makes the bike handle and look like a TW-200. The 606 130 size is about a 8% taller gear tire. Don't have the exact diameter in front of me, but as I recall when I put the 47 tooth and the 130 tire my net gear reduction ratio was about 8% (16% gear less 8% tire gain = 8% lower gear.

Done