Naked lap times!

[Roja]

Dear colleagues,

I've been having discussions with other riders (of all levels) about a very important topic for me. I want to know how much faster is a faired sports bike around a given track than the SDR. I've brought up different race results for the same track - in order to keep the findings as empirical as possible.

I've calculated the time lost at top speed on the main and back straights. I've wondered if the aerodynamics in corners plays as big of a role (as and advantage) as the short suspension on a racing bike plays (as a disadvantage). I've calculated the exponentially smaller influence of aerodynamics at slower speeds and the fact that 'upward' airflow converts to downward push on the front end - something that works well when the bike is perpendicular to the track, and less so when the bike is leaning at 45 degrees.

Given the same rider skill, with same tyres and same knowledge of the bikes and tracks, what would the real difference be (measured in seconds) on a 5 km long track? I'm speaking of an SDR1290 vs a Pani 1299 (or something similar).


Why? Because I'm at the point of either getting slicks and warmers for the SDR to see if I can drop lap times or go out and get a racing bike.
HOWEVER, this last question is neither here nor there. My desire is to see if anyone has some valuable data or experience to add to the original argument (in bold).

Thanking you kindly in advance!

[shadowman]

I saw an interview with Jeremy McWilliams who obviously possesses more skill on track than the average human being.

He was asked this very question and answered that over three different tracks (can't remember if he said which ones) with a fully set up SDR he could match lap times to within a second of the track only version of the RC8. A couple of things to bear in mind when considering this statement;

1) He could ride more or less anything faster than 99.9% of people on the planet and is much more able to ride round any disadvantages than a more normal rider would be
2) His SDR would have been the top powerparts special with a full system and map and running on slicks.
3) Drag squares with speed - twice as fast is four times the drag, three times is nine times the drag - The aerodynamic disadvantage will obviously be higher on faster tracks with long straights
4) For most people comfort and confidence will yeild more in lap time than HP and fairings ever will.

I'm sure you could find the McWilliams interview online somewhere

[Miki]

Can’t compare any “decent” track bike but few experience after 2 summers and 30 track days with my SDR1290.
How do I improve my lap times step by step.
Riding position, stock handlebar is too high and has too much sweep.
Front suspension is weakest link of the bike. Mine is re-valved and it’s ok but far from perfect. Cartridge kit may solve this. Rear suspension need just little work and it’s ok.
Tyres, started with Supercorsa SP’s without warmers. Last summer have used only SC1 or Racetec K1 with warmers. Stock suspension can’t handle that entire grip.
Suspension settings, probably never easy job with any bike. I had lot of problem with tyre ware last summer. I improved my lap times rapidly and destroyed lot of tyres. Finally found out rear suspension’s sag should be less than I expected and tyre pressure must be higher also. There’s so much weight on the rear tyre exit of the corners.
ABS pulse is annoying on the track. Better use Supermoto mode or no ABS. Braking is much more controllable and breaking distance way shorter.
Brake pads, never use original. Can’t stand heat.
Lean angle, specially, on the right is disadvantage. I have worn out de-cat pipe, pedals and clutch cover protector. Few exciting moments when clutch cover hit the track 
Gearing, gap between 5th and 6th is too big. 6th is totally useless and 5th hit the limiter some places.
Aerodynamics, SDR1290 and (really) fast 600cc (rider) reach same top speed on track. 1000cc get 20-30 kph higher top speed.
So conclusion, SDR1290 is fun wherever. Engine is great even stock. Unfortunately KTM has underestimated customer some points and used crap components for serious riding. Sure you can spend lot of money afterwards and buy this and that. I have a feeling after 2 summers on the track SDR1290 can’t give me anything more. Need real track bike for that purpose. Track bike is track bike, SDR1290 is fun bike.

[Roja]

Shadowman and Miki, thank you guys!!!

Both of your answers were very informative and precisely what I was hoping to read.
It's like you were both along for every single discussion I've been having on the topic.

Miki, I've come to the same conclusions with suspension - put in cartridges and an Ohlins. For brakes, changed out fluid, put on WavePP rotors and brought my lever out by two steps.
ABS kicks in all the time, though I find it annoying, I also consider it rather smooth (regardless, it's a hindrance).

Gearing is totally true also, and I find myself being very careful to not miss the 5 to 6.


It's great to know it's not all in my head! I see that my obvious next step is to get warmers and move on to slicks.

Miki, about KTM and underestimating riders and crap components, I disagree with you ONLY in that I think they didn't underestimate anything. I think they knew very well that some people would want to upgrade suspension, etc...so they went with the PowerParts catalogue! They're trying to make money (perhaps a little too greedy, given their embryonic experience and reputation in the on road sector).


Again, thank you both!!! If ever in Barcelona, PM me, I'll buy you a beer!

[Edorta]

Years ago in Motorland a friend try to do this "stupid" test with his R1.

He do all the back part of the circuit in attack position first, and another lap with street position (head up out of the frontal fairing)

The diference was between 20-30 kms/h....with the same bike!!

So imagine how important are the fairings and q correct position.

[Miki]

Roja,

"Miki, about KTM and underestimating riders and crap components, I disagree with you ONLY in that I think they didn't underestimate anything. I think they knew very well that some people would want to upgrade suspension, etc...so they went with the PowerParts catalogue! They're trying to make money (perhaps a little too greedy, given their embryonic experience and reputation in the on road sector)."

Absolutely right, just my not so humble subjective opinion
You'll enjoy track days with slicks and warmers I'm sure. Follow tyre ware and set up suspension carefully.

[Roja]

Thank you Edorta and Miki.

In a couple of weeks, there'll be a two day course on suspension and telemetry. I'm looking forward to it.

I tend to like my suspension softer than 'typical', but with a change to slicks, I'm going to have to go through the adjusting process again - it's part of the hobby!