16 Tooth sprocket

Here be mechanigeeks. Anything technical that is not a teething problem.
User avatar
White Knight
675cc
675cc
Posts: 195
Joined: Sat Apr 09, 2011 4:42 pm
Country: Canada
City: Victoria
Year: 2011
Colour: White

Re: 16 Tooth sprocket

Post by White Knight » Wed Jul 06, 2011 6:14 pm

After having the SMT for a couple of months now, I have a hard time seeing the 16 tooth being anything more than a wheelie gear! I think... and the good lord knows I am frequently wrong, but I think that it might actually negatively impact acceleration in that 1st, 2nd, and maybe even 3rd, I doubt I could keep the front on the ground while whipping it's balls! The front already gets light in 3rd with the stocker 17 on. Can you hooligans crack the throttle wide open in 2nd with the 16 and get massive forward motion without having the rear overtake the front underneath?

I guess the only way to prove my theory is however, to try it! :lol:
Image

User avatar
kevxtx
Moderator
Moderator
Posts: 4739
Joined: Fri May 27, 2011 11:40 am
Country: Australia
City: Brisbane
Year: 2014

Re: 16 Tooth sprocket

Post by kevxtx » Thu Jul 07, 2011 10:05 am

It's hard to keep the front end down, but I perfer the 6th gear 60kph cruising with the 16T sprocket. The roll on from 4000rpm is much better than the 17T sprocket.

Marcelo
250cc
250cc
Posts: 77
Joined: Wed Apr 06, 2011 12:54 am
Country: Brazil
City: sao paulo
Year: 2010

Re: 16 Tooth sprocket

Post by Marcelo » Thu Jul 07, 2011 5:35 pm

I agree, in cruising with the 16T sprocket is totally better than 17T

regards

Loosecheez
125cc
125cc
Posts: 12
Joined: Sun Jun 19, 2011 3:43 pm
Country: USA
City: Lexington, KY
Year: 2011
Colour: White

Re: 16 Tooth sprocket

Post by Loosecheez » Mon Aug 01, 2011 3:56 am

Another thumbs-up for the 16t... I was initially worried about the sprocket making the bike wheelie happy but that hasn't been the case. The 16t fights the low rpm lumpiness by keeping the bike in the sweet spot longer. The bike behaves much better in-town and you have to worry less about being in the perfect gear exiting out of tight corners. First gear is a little short and there is a 5mph penalty for the same RPM on the highway but the positives have outweighed the negatives for me.

Electrified
250cc
250cc
Posts: 40
Joined: Tue Jul 12, 2011 6:47 pm
Country: United States
City: Houston
Year: 2010
Location: Houston, TX

Re: 16 Tooth sprocket

Post by Electrified » Sat Aug 27, 2011 4:54 am

I installed the 16 tooth sprocket tonight and will take it on for a ride in the morning. I think the 16t will definitely make 6th gear more usable because as it is now, I can seldom use the top cog. I suppose if I did more open road riding the 17t would be more useful but I spend much of my time riding around the general vicinity of my home. I will give my opinion tomorrow.

Thanks for all the useful input.
Steve
2010 SMT-990 ORANGE
Wings Exhaust, G2 Throttle tamer16T sprocket, California Scientific Smoke Touring windshield, 47L Trax side cases, Givi top case

User avatar
kevxtx
Moderator
Moderator
Posts: 4739
Joined: Fri May 27, 2011 11:40 am
Country: Australia
City: Brisbane
Year: 2014

Re: 16 Tooth sprocket

Post by kevxtx » Sat Aug 27, 2011 9:42 am

I refitted my 17T front sprocket last week to see if my now improved 123hp engine would pull better with the 17T front sprocket (I rode 400kms with the 17T back on) it doesn't, I refitted my 16T back on today, much better with the 16T.

jonty
900cc
900cc
Posts: 331
Joined: Sun Oct 10, 2010 8:45 pm
Country: Northern Ireland
City: Downpatrick
Year: 2010

Re: 16 Tooth sprocket

Post by jonty » Sat Aug 27, 2011 3:04 pm

I`ll be honest and say the gearing is perfect for the roads that I ride.

4th or 5th are idea for most of them [B roads and some twisty A`s]

6th gear really is an overdrive economy gear.

5th gives good grunt with midrange acceleration and is fine for cruising even if you are having short bursts of near 3 figure speeds.


First is actually a usable gear rather than just a "get you rolling"

Electrified
250cc
250cc
Posts: 40
Joined: Tue Jul 12, 2011 6:47 pm
Country: United States
City: Houston
Year: 2010
Location: Houston, TX

Re: 16 Tooth sprocket

Post by Electrified » Sat Aug 27, 2011 8:05 pm

After riding about 150 miles this morning on the new 16t sprocket, I have to say the bike rides much better. It seems to ride smoother in all gears and raises the rpm's just enough to keep me in the sweet spot at the posted speed limits. Very happy with the switch.
Steve
2010 SMT-990 ORANGE
Wings Exhaust, G2 Throttle tamer16T sprocket, California Scientific Smoke Touring windshield, 47L Trax side cases, Givi top case

User avatar
kevxtx
Moderator
Moderator
Posts: 4739
Joined: Fri May 27, 2011 11:40 am
Country: Australia
City: Brisbane
Year: 2014

Re: 16 Tooth sprocket

Post by kevxtx » Sun Aug 28, 2011 4:52 am

I forgot to mention I extended my rev limiter from 9500 to 9750 to compensate for the shorter gearing with the 16T front sprocket,

Standard gearing 17/41 gearing in 1st gear @ 9500 = 95kph
Rev limiter raised 16/41 gearing in 1st gear @ 9750 = 92kph
Standard rev limiter 16/41 gearing in 1st gear @ 9500 = 89.4kph

So not much in it.

Electrified
250cc
250cc
Posts: 40
Joined: Tue Jul 12, 2011 6:47 pm
Country: United States
City: Houston
Year: 2010
Location: Houston, TX

Re: 16 Tooth sprocket

Post by Electrified » Sun Aug 28, 2011 7:15 pm

How do you raise the rev limiter?
Steve
2010 SMT-990 ORANGE
Wings Exhaust, G2 Throttle tamer16T sprocket, California Scientific Smoke Touring windshield, 47L Trax side cases, Givi top case

User avatar
kevxtx
Moderator
Moderator
Posts: 4739
Joined: Fri May 27, 2011 11:40 am
Country: Australia
City: Brisbane
Year: 2014

Re: 16 Tooth sprocket

Post by kevxtx » Mon Aug 29, 2011 12:57 am

Using Tune ECU, upload your map from your bike, click on rev limiter, click up or down to the rev limiter you want, save map then download to your bike, all done.

A word of warning increasing your rev limiter will effect your warranty, I would not go more than an extra 250 rpm.

Electrified
250cc
250cc
Posts: 40
Joined: Tue Jul 12, 2011 6:47 pm
Country: United States
City: Houston
Year: 2010
Location: Houston, TX

Re: 16 Tooth sprocket

Post by Electrified » Wed Aug 31, 2011 3:23 am

I think I am going to leave that one alone. Although I have been riding for 25 years, I seldom rev a bike to max RPM's as my skills have never surpassed the bike I was riding and that especially holds true for SMT. When I nail the throttle on this thing, it almost feels like it is going to fly right out from under me but I have only been riding it for a couple of months. Perhaps I will crave an increase in RPM's in the future but for now it is more than I can handle. :ugeek:
Steve
2010 SMT-990 ORANGE
Wings Exhaust, G2 Throttle tamer16T sprocket, California Scientific Smoke Touring windshield, 47L Trax side cases, Givi top case

ultrachrome
675cc
675cc
Posts: 237
Joined: Thu Apr 14, 2011 11:14 pm
Country: USA
City: Seattle
Year: 2011
Colour: White

Re: 16 Tooth sprocket

Post by ultrachrome » Sat Jun 16, 2012 5:16 pm

I haven't seen anyone talk of fuel mileage with the 16t. I'm pretty obsessed with tracking my mileage and have tracked every fill up with Fuelly.

I anticipated a drop with the 16t but after three fill-ups I can't say I see a difference.

Like everyone says, the bike is significantly easier to ride in traffic so for me it's a win-win.

User avatar
kevxtx
Moderator
Moderator
Posts: 4739
Joined: Fri May 27, 2011 11:40 am
Country: Australia
City: Brisbane
Year: 2014

Re: 16 Tooth sprocket

Post by kevxtx » Sun Jun 17, 2012 1:01 am

Electrified wrote:I think I am going to leave that one alone. Although I have been riding for 25 years, I seldom rev a bike to max RPM's as my skills have never surpassed the bike I was riding and that especially holds true for SMT. When I nail the throttle on this thing, it almost feels like it is going to fly right out from under me but I have only been riding it for a couple of months. Perhaps I will crave an increase in RPM's in the future but for now it is more than I can handle. :ugeek:
The 16t front sprocket is not about reving the bike hard at higher rpms, it is about more throttle control in every gear at low speeds especilaly if you ride around a low rpms.

Bootworks
Supporter
Supporter
Posts: 443
Joined: Sat Dec 04, 2010 11:31 pm
Country: USA
City: Livermore California
Year: 2014

Re: 16 Tooth sprocket

Post by Bootworks » Sun Jun 17, 2012 4:51 pm

Using a sprocket calculator, going from the stock 17/41 (2.41 ratio) to 16/41 (2.56 ratio) will increase torque 5.9% and drop speed for a given rpm 5.9%,

http://www.sprocketcalculator.com/

A "milder" combination would be 16/40 (2.50 ratio): T+3.5%, S-3.5%

Doerbird02
500cc
500cc
Posts: 92
Joined: Sun Jun 10, 2012 3:25 pm
Country: USA
City: Monterey, CA
Year: 2012
Colour: White
Model: SMT
Location: Monterey, CA

Re: 16 Tooth sprocket

Post by Doerbird02 » Mon Jun 18, 2012 1:35 pm

The one thing I haven't seen anyone talk about is if changing to the 16T requires a speedo calibration. I have a Speedo Healer on my 600rr because I've changed the sprockets and there is a change to the indicated speed. Not a huge deal, but frustrating to know that if you're in a speed sensitive area, that your Speedo is lying to you. If the speedo is fed from the wheel directly though, I suppose it doesn't matter then. Just don't know where the SMT gets its speed reading from.
Rotweiler, Leo Vince cans, SAS and Canister removed, 2nd Flies Removed, Kev's #20 map, forks heavier springs and custom valving from KTM World, random orange anodized bits for looks
Image

Bootworks
Supporter
Supporter
Posts: 443
Joined: Sat Dec 04, 2010 11:31 pm
Country: USA
City: Livermore California
Year: 2014

Re: 16 Tooth sprocket

Post by Bootworks » Mon Jun 18, 2012 3:53 pm

Doerbird02 wrote:The one thing I haven't seen anyone talk about is if changing to the 16T requires a speedo calibration. I have a Speedo Healer on my 600rr because I've changed the sprockets and there is a change to the indicated speed. Not a huge deal, but frustrating to know that if you're in a speed sensitive area, that your Speedo is lying to you. If the speedo is fed from the wheel directly though, I suppose it doesn't matter then. Just don't know where the SMT gets its speed reading from.
If I recall correctly I read a post stating the speedo pickup is from the front wheel and it remains unaffected.

phxrider
250cc
250cc
Posts: 62
Joined: Thu Aug 04, 2011 4:56 pm
Country: United States
City: Gilbert
Year: 2010
Model: SMT

Re: 16 Tooth sprocket

Post by phxrider » Mon Jun 18, 2012 7:25 pm

Yep, the speedo runs off the front wheel on the KTMs. Remember they are a dirt racing company first, and changing wheels and converting from 18/19" rears and 21" fronts for MX & cross country to 17" wheels for Supermoto racing is par for the course in their world.

I just did the 16T front (along with the beautiful KTM stealth sprocket in back and DID ZVM-X chain) and definitely recommend this change. This is how the bike should have come from the factory. Like everyone says, it's smoother and quicker at the same time. Also, the much-hated SMT chain flap seems to be lessened too.

I mostly disliked the 16T on my 950 Adventure as I thought it made the top gear too short on the highway, but the SM series has a taller top gear ratio that makes all the difference during highway cruising.
-Rob
--
2010 990 SMT, 2008 690 SMR

Random00
125cc
125cc
Posts: 32
Joined: Mon Jan 23, 2017 5:11 pm
Country: United States
City: Los Angeles
Year: 2012
Colour: White
Model: SMT

Re: 16 Tooth sprocket

Post by Random00 » Thu Aug 16, 2018 9:31 pm

beyond wrote:
Wed Jun 01, 2011 1:11 pm
Marcelo:

I've done both mods and haven't noticed any significant change in fuel usage, maybe a few less miles before the light comes on but I do mean a few less, 5 tops. I've also disconnected the 2nd/3rd gear limiter cables.

I got the dealer to change the sprocket during the second service so can't help you with removal.
What the wat? Gear limiter cables???? I did a forum search and couldn't find anything on that. Can anyone educate me?

User avatar
kevxtx
Moderator
Moderator
Posts: 4739
Joined: Fri May 27, 2011 11:40 am
Country: Australia
City: Brisbane
Year: 2014

Re: 16 Tooth sprocket

Post by kevxtx » Fri Aug 17, 2018 10:41 am

Random00 wrote:
Thu Aug 16, 2018 9:31 pm
beyond wrote:
Wed Jun 01, 2011 1:11 pm
Marcelo:

I've done both mods and haven't noticed any significant change in fuel usage, maybe a few less miles before the light comes on but I do mean a few less, 5 tops. I've also disconnected the 2nd/3rd gear limiter cables.

I got the dealer to change the sprocket during the second service so can't help you with removal.
What the wat? Gear limiter cables???? I did a forum search and couldn't find anything on that. Can anyone educate me?
Removing EPC Electronic Power Control, here you go: viewtopic.php?f=13&t=3076

Post Reply