View Full Version : Gearing for Larger Tracks


Broom
March 4th, 2009, 01:05 PM
Hey guys,

the last track i had the 250 out on was a 1.7 mile, very technical track and we ran 14/47 gearing. it seemed like the bike was kinda topping out on the straight (no rev limiter cut in), but i was hesitant to go taller with the gearing because i wasn't sure that the bike was going to pull it and actually be any faster.

i'm about to head out to Eagles Canyon Raceway next weekend for a track day and a few sprints. this track is larger at 2.5 miles (probably too big for the 250). anyone have any recommendations on gearing for the larger tracks like this? if i return the gearing to stock is it going to pull it, or slow me down?

track map for kicks. click for more info:
http://www.eaglescanyon.com/2008/img/ECR-Map-2-1-08.jpg (http://www.eaglescanyon.com/2008/facilities.php)

kkim
March 4th, 2009, 01:07 PM
I believe Richard runs a 15T CS sprocket.

RaceBikeRentals
March 5th, 2009, 08:59 AM
I'm running stock 14/45 at Willow Springs, which is pretty much the fastest track out there. I'd start with stock first, then remove a tooth if you feel you need more top end. Stock gearing is pretty good, actually. I'm using it for Willow Springs, Buttonwillow and Infineon.

Broom
March 5th, 2009, 09:23 AM
cool, we'll start with that then. hopefully we can figure out a setup that'll let us switch between the 47t and the 45t without changing chain length.

kkim
March 5th, 2009, 10:54 AM
Richard,

Didn't you have a 15T at one time? I thought I remembered you trying one for more top end for the larger tracks.

RaceBikeRentals
March 5th, 2009, 11:15 AM
No, never tried it. I went down to a 43 on the rear once & promptly lost a second a lap due to weaker drive out of the corners.

kkim
March 5th, 2009, 11:28 AM
Okay... I thought I had seen you in a discussion on another forum :D when the 15T was first being installed on the new gen bikes and you were running your bike at WS on the big track that you were looking for a bit more top end.

Good to get your feedback on gearing. Have you ever tried going up in gearing?

RaceBikeRentals
March 5th, 2009, 11:32 AM
Haven't tried it, but I normally run BT016 tires vs my competitor's 090s. My 150/60 vs their 140/17 equates to about 1.5 teeth difference according to my butt calculator. I was at LVMS a few weeks ago and should have added a couple teeth, but was too lazy :)

kkim
March 5th, 2009, 11:39 AM
lol... I have both 13T and 15T CS sprockets laying on my workbench and have been too lazy to change mine out, too. I was hoping to get some feedback from you thinking that you might have played with gearing to maximize you advantage at the track. :D

RaceBikeRentals
March 5th, 2009, 11:42 AM
These are a lot of race-type questions coming from you, Kelly. Going racing any time soon? :D

kkim
March 5th, 2009, 11:46 AM
I wish. :(

Broom
March 5th, 2009, 11:59 AM
i started off my track day last month with 13/47... it was awesome. lots of power but topped out too fast on the straight. bike felt fast though. would be a blast on a 1 or 1.5 mile track.

almost40
April 5th, 2009, 12:12 AM
Well, guess Ill be going back to the stock rear sprocket for my non straight track weekend. It seems funny to me That all you guys gear down, but it makes sense. I usually only race in a straight line and the taller gear gets better times. Guess that kind speed isnt that good for the race track huh?