Loudon.....Gearing Question

[By-Tor]

Last year at Loudon I found that I could only use 2nd and 3rd gears on my 954RR. On the back straight I would shift into 3rd and hit the soft limiter at about 133mph a split second before I would hit my braking marker and then down shift back to 2nd just before turning into turn 1. I found the straight to be too short to hit 4th gear.

This year I will be doing trackdays at Loudon on my 1000RR and would like to keep from hitting the limiter. I have been thinking about swaping my 16 tooth front sprocket for a 15 and upping my rear 41 tooth to a 42. This should lower my gearing enough to allow me to use 2nd, 3rd, and 4th at the track.

Any thoughts as to why I should or shouldn't do this?

What experiences or advice do you guys have for "gearing" down for Loudon?

[Degsy]

It's different for every bike, and different as you get better and get on the power earlier and brake later but as a general rule of thumb you want to be at about a 1-3 ratio, so 15/41 would be about right.

derek

[By-Tor]

So my theory about lowering my gearing to allow me to use more transmission gears holds water?

[Degsy]

absolutely.

[beet]

not reach for kind of spin freely

[OreoGaborio]

Originally posted by beet
not reach for kind of spin freely

............................................................. WHAT????

[By-Tor]

Glad I'm not the only one!


I'm sure the gearing change will help with my drive out of turn 3. The RR's are a bit long in the leg and can sure use a bit lower gearing. The more I think about this the more excited I get about doing the sprocket swap

[By-Tor]

HAHAHAHAHAHAHA!!!!!!!!!!!!

I just stoped by my local bike shop to pick up some oil, filter and get a price on the sprockets. I told the parts guy that I wanted to go down a tooth in the front and up a tooth in the rear and gave him the tooth count for each sprocket.

He tells me " They will cancel each other out so I might as well keep the stock sprockets"

So me to him........ "I'll just take the oil and filter please........"

And I got the hell out of there for fear that his stupidity might be contagious

[beet]

Originally posted by OreoGaborio
............................................................. WHAT????

ya want 2 hit top speed bfor the end of the long strait not just as ya get 2 the end of it
They will cancel each other out so I might as well keep the stock sprockets"
this is bs the guys a git

[By-Tor]

I don't think it's possible for a 954 or 1000RR to hit top speed on such a short straight

[smoothwaterman]

I had the same issue at Loudon with my 954. And with the grunt of it you could carry the speed and just leave it in 3rd if you got lazy....

Anyhow, since I'll be still riding on the street, I opted to just go up 2 in the rear, so I'm running 16/45. Most that I spoke with or read about that went racing changed over to -1,+2, for a 15/45.

3rd gear, 70 mph, the tach will now be 295 rpm greater using 16/45 on the 954. Dropping the front to 15 will bump that number to 737 rpm over stock. Big difference. 15/42 is a 580 rpm jump.

The only thing is now you have to control your wrist to an even smoother degree, and keep the weight forward. I'm a two wheels down guy.

pb.

[By-Tor]

Cool. Great info CWM

Yup, I'm gonna order a 15 tooth for the countershaft and put it on right away and get a 42 to replace my 41 rear. I'll hold off on installing the 42. I'll bring the 42 with me to the June 2 trackday at Loudon and if I feel the need, I'll swap it out during one of the breaks. I figure this is the best way of keeping track of the gearing changes.

If I don't like the added rear sprocket, I'm sure I could eBay it real quick.

[beet]

Originally posted by By-Tor
I don't think it's possible for a 954 or 1000RR to hit top speed on such a short straight

but top 1000rr speed @ loudon
you will b hitting 145-150 now

[guru_lou]

You really want to consider lowering the gearing enough to be near redline in 6th gear at the end of the straight. This will put your gear changes into the 3rd, 4th, 5th and 6th instead of 2nd, 3rd, and 4th. The spacing between gears is much smaller in the top gears rather than the bottom, effectively giving you all the advantages of a close ratio transmission. Using the lower gears causes the rpms to drop too low with each shift and keeps you out of the "sweet spot" with each shift. Think more in terms of a 15/43 or 44.

[OreoGaborio]

Originally posted by guru_lou
You really want to consider lowering the gearing enough to be near redline in 6th gear at the end of the straight. This will put your gear changes into the 3rd, 4th, 5th and 6th instead of 2nd, 3rd, and 4th. The spacing between gears is much smaller in the top gears rather than the bottom, effectively giving you all the advantages of a close ratio transmission. Using the lower gears causes the rpms to drop too low with each shift and keeps you out of the "sweet spot" with each shift. Think more in terms of a 15/43 or 44.

Yeah, that's the ideal way to do it, but the problem w/ that is i believe this is also his street bike.... and although that'd be pretty fun, lowering the gearing that much would be pretty unreasonable for street duty unless he's gonna change it back & forth between every track day... at which point you've also gotta wonder about swapping chains if the gearing change is drastic enough to require a different length chain.

my recomendation: get a smaller cc track rat

[TLRMan]

He said "Sweet Spot!"......

I hit all 6 gears with my dragbike, and it was done just before the 2nd. MPH trap....

[OreoGaborio]

bastard... turn your phone on, i just called you.... i wanted to say ""

[TLRMan]

Originally posted by OreoGaborio
bastard... turn your phone on, i just called you.... i wanted to say ""

I just IM'd you...

[OreoGaborio]

and i just PMed you...

[beet]

of chain & sprockets ya git

[By-Tor]

Originally posted by beet
of chain & sprockets ya git

One step ahead of ya

I'm buying an extra cush drive off eBay to keep the larger rear sprocket on. That will make swaps real quick

[By-Tor]

My final gearing decision will have to be made through a bit of trial by error though.

A dedicated track bike would be cool but with my 2 month old son it is just not in the cards right now.

That kid is eating us out of house and home

[guru_lou]

Sorry, I didn't catch that this was going to be a street bike also, so the 15/42 would get you real close to being right for both. You'll really like the ease of it off the stop lights and the extra torque on the track. You can usually go down one in front and two up in back without changing the chain. The only other thing to watch out for is the effect of engine braking. If you're a track newbie, it won't bother you, but it does add extra load to the front tire. For the street, you may also want to consider a speedometer recalibrator from Yellow Box or Jim Ahlman. They fix the speedometer/odometer error from the re-gearing.

[By-Tor]

Yeah, A speedo-healer is a must have once I do the gear swap. I'm not a track newbie, but since the 954 is now in motorcycle heaven, this will be the first time my 1000RR will be on the track

Thanks for all the help guys. Hope to see you all at the track on June 2nd

I'll be the guy on the Silver 1000RR with the 1000rr.com stickers

[Paul_E_D]

Well, Your RR will be nothing like your 954 so I'd wait and see, but I just wanted to add a few things about gearing. It's not as simple as saying it's best to top out 6th on the straight.

At loudon, there are 11 turns to consider while making that decision. I know that even the fast SV guys are not using sixth gear, along with most any bike faster than an SV.

The problem with gearing for the straight is that first gear might become so short that it is useless (revs too high) in the slow turns (3 and 12). The gap to second is often big enough that you will be soft on the power as you exit these turns. While you wait for your engine to spool up, the other bikes are leaving you for dead.

This is just an example, but it could happen in any gear/turn as you change the gearing. This is why real race bikes have cartridge type gear boxes. They can change the internal ratios to maximize both the straight away, and the acceleration off of important turns on the track.

The best way to go is to ask some local expert racers who ride the same bike as you what their gearing is, and then gear it 1-2 teeth shorter. You'll never have the corner speed to use their gearing, but I have found that one or two teeth shorter than the hot set-up is usually the most rideable set-up...

Most of this doesn't matter to a track day rider unless you have a particular problem with shift points such as the one mentioned in the first post.