Leaning on straight

[ducatmh]

I've been riding on track for about 4 years now and have done CSS Level 4 umpteen times by now so I'm not a noob by most standards. However, this season I have experienced something on my home track that I haven't in the past at any track. Coming out of the final corner onto the straight,  I have found my RSV4 not standing straight up for a good portion of the straight as I power on. I'm trying to figure out what might be causing that to happen. Is this a typical occurrence or am I unknowingly giving the bike input causing it get a slight lean? I ALMOST feel like I'm fighting it which really makes me think I must be doing something it doesn't like.

*The last corner is a tight slow left and the bike wants to stay leaned ever so slightly to the left.

*The only thing to change between the seasons is my speed and the RSV4 is new to me. (1199S & 1198S prior years)

Open to thoughts and happy to clarify if I am able. 

[Jaybird180]

Does the bike go straight during other straights?

[ducatmh]

It does.  It’s the only track that it does this to me. I’ll be there again this coming Sunday so I will be putting more attention on what, if any, inputs I may be giving the bike. It has been about 4 months since... so perhaps my recollection of some of the details of the scenario have been lost as well. For example... after posting last night I laid there and was wondering if maybe the bike was actually leaning to the right vs left.  BTW... when I say “lean” I really mean that the bike is just off its vertical axis.

[DLHamblin]

On 10/8/2017 at 8:51 AM, ducatmh said:

It does.  It’s the only track that it does this to me. I’ll be there again this coming Sunday so I will be putting more attention on what, if any, inputs I may be giving the bike. It has been about 4 months since... so perhaps my recollection of some of the details of the scenario have been lost as well. For example... after posting last night I laid there and was wondering if maybe the bike was actually leaning to the right vs left.  BTW... when I say “lean” I really mean that the bike is just off its vertical axis.

Any chance you can get someone to video you?  Video can be a powerful tool in these type cases.

[ducatmh]

5 hours ago, DLHamblin said:

Any chance you can get someone to video you?  Video can be a powerful tool in these type cases.

I'll see what i can do.   I can add that it doesn't do it on my  little bike. (R3) LOL

[Jaybird180]

Has the bike been crashed? How about the installation of the wheels? Some bikes have a specific procedure regarding which bolts should be torqued in which order (you do use a torque wrench, right?). Also, where is your weight centered when coming off the final corner? Do you stand the bike up swiftly or gently bring it up in sync with the power?

 

Just a few possibilities. That’s the best of what I have of value to help.

[ducatmh]

Thanks for the ideas.  The bike is mechanically sound so I am fairly certain it's not the bike, it's the operator... me LOL.  I'm an avid "pick up" artist on track so the bike is typically picked up before I'm back in line with the saddle.  Just trying to determine if it's "normal" in certain scenarios.  i.e. this bike is tuned to 215 HP, it's a former professional race bike (MotoAmerica) so has gobs of mid-range power compared to the stock setup....  the front wheel gets light coming on the straight (Surprise!!). Is it possible/likely that with the front end lifting a little before upright, the gyroscopic effects cause this sensation I'm getting?  Does that even make sense? OR is it me hanging on for dear life and putting unwanted input into the controls?   I definitely have some research to do on track this weekend.  Hopefully the weather cooperates!

[ducatmh]

HOTFOOT where are you?!? Hoping you would chime in!!

[Jaybird180]

2 weekends ago I was at a session with Dave Moss and he talked about buying former race bikes and the new owner failing to adjust the bike to themselves, believing the bike to be best “as-is”. Dave believes this to be in error and almost implied that the bike should be gone over with a fine tooth comb. He did say all the settings should be removed and baselined for the new owner.

[ducatmh]

I flew into Houston to take delivery of the bike at the end of last year. The engine was torn down and rebuilt and the tune was also dumbed down a bit from what they ran in the races prior to the purchase. We (Bobby, one of his techs and I) spent the day at MSR (local track there) adjusting the bike to my needs so hopefully that's not an issue in this scenario.  It was only one day of tweaking a "new bike" on a "new-to-me" track so I can appreciate the limitations of the adjustments made. That said, overall the bike handles like a dream, is more compliant and confidence inspiring than my Ducati's ever were, the mid-range stomps the Ducati's as well (to be expected since that's one of the Panigale's many shortcomings) and best of all, my lap times dropped by a couple seconds within a few laps. 

[Jaybird180]

I guess that only leaves 2 options:

1- a previously unnoticed camber or line change

2- the nut connecting the seat and handlebars ? 

[ducatmh]

LOL... Probably the "nut"!

[Hotfoot]

On ‎10‎/‎9‎/‎2017 at 8:42 PM, ducatmh said:

Thanks for the ideas.  The bike is mechanically sound so I am fairly certain it's not the bike, it's the operator... me LOL.  I'm an avid "pick up" artist on track so the bike is typically picked up before I'm back in line with the saddle.  Just trying to determine if it's "normal" in certain scenarios.  i.e. this bike is tuned to 215 HP, it's a former professional race bike (MotoAmerica) so has gobs of mid-range power compared to the stock setup....  the front wheel gets light coming on the straight (Surprise!!). Is it possible/likely that with the front end lifting a little before upright, the gyroscopic effects cause this sensation I'm getting?  Does that even make sense? OR is it me hanging on for dear life and putting unwanted input into the controls?   I definitely have some research to do on track this weekend.  Hopefully the weather cooperates!

Have a look at Twist of the Wrist II, Chapter 13  "Steer for the Rear". The fourth paragraph, in particular, may shed some light on the situation.

[ducatmh]

 

1 hour ago, Hotfoot said:

Have a look at Twist of the Wrist II, Chapter 13  "Steer for the Rear". The fourth paragraph, in particular, may shed some light on the situation.

Awesome! Thanks... so it looks like my frame of thinking was on the right track. Assuming no extraneous inputs from me, this is "normal". I'll still put a bit of attention on it this weekend to see if I come up with any other observations or questions. Forecast is 64 degrees, sunny with 10% chance of rain. Doubt I'll set any PB's with the cooler track surface.

[Jaybird180]

On 10/11/2017 at 10:28 AM, Hotfoot said:

Have a look at Twist of the Wrist II, Chapter 13  "Steer for the Rear". The fourth paragraph, in particular, may shed some light on the situation.

Not only am I also looking at that chapter I'm also looking at the subsequent chapters with a fresh perspective.

[ducatmh]

Nothing terribly exciting to report after the last track day.  It certainly seems that it is related to the front wheel lifting on the drive out before the bike is perpendicular to the track.  Allowed me to focus more on getting down the track knowing that it was "normal". Overall it was a great day though I was still .5 off my PB but found at least 3 turns that need some attention that should yield me 4-5 seconds once I get them sorted. Next season!

Hopefully I'll see the CSS crew again in Feb @ LVMS or Code RACE in March 2018

[Jaybird180]

You must have sector time data to be able to estimate 4-5 seconds for those 3 corners???

[ducatmh]

Reviewing on-board video footage helped me guesstimate. I can extract GPS data from my lap timer to get more accurate sector times, but that would be overkill for my needs at present. Just setting goals for next season.

[Hotfoot]

20 hours ago, ducatmh said:

Nothing terribly exciting to report after the last track day.  It certainly seems that it is related to the front wheel lifting on the drive out before the bike is perpendicular to the track.  Allowed me to focus more on getting down the track knowing that it was "normal". Overall it was a great day though I was still .5 off my PB but found at least 3 turns that need some attention that should yield me 4-5 seconds once I get them sorted. Next season!

Hopefully I'll see the CSS crew again in Feb @ LVMS or Code RACE in March 2018

Glad to hear you are comfortable with what the bike is doing and have a better understanding of it, especially since you were able to use the freed-up attention to improve your focus on the drive out of the corner, that is a great win.

So, what is it about those three corners that would get you 4-5 seconds off your lap time? Are they turns leading onto straights, or very long, fast turns...? Since you have data and GPS I'm curious.

[ducatmh]

Great question and I feel like I've put a lot of thought into it and honestly I think the most useful tool was not my lap timer or my onboard camera... it was actually footage from my friend's bike who followed me for a few laps.

I attached an image of the track to help in visualizing the turns. Unfortunately, the map doesn't show elevation changes (yes there are a few hills in Kansas LOL). The only notable elevation changes occur on the front straight up to T0 (uphill with zero visibility of what's ahead, you crest the hill about the same time you hit T0 and then downhill into T1), the very short straight section between T5 & T6 (slight downhill) and then again T7 to T8 (slightly back uphill).

The most time could be made up T14 onto the straight, T3 (T3 reminds me of the bowl at the Streets of Willow but with less banking), T7 and T9.  I won't bore you with the details of how exactly I will address these areas but I will tell you that depending on the turn or turns leading up it's over braking, position on track at entry, late roll on and/or not pinning the throttle soon enough. I'm sure we could tie a handful of these to needing better RP's.

 

5 hours ago, Hotfoot said:

Glad to hear you are comfortable with what the bike is doing and have a better understanding of it, especially since you were able to use the freed-up attention to improve your focus on the drive out of the corner, that is a great win.

So, what is it about those three corners that would get you 4-5 seconds off your lap time? Are they turns leading onto straights, or very long, fast turns...? Since you have data and GPS I'm curious.

 

[Jaybird180]

Interesting...looks like the unmarked 10a will be key to getting T14 set up properly.

[ducatmh]

Yeah, I had spent like 20 minutes outlining the "issues" with how I was attacking various areas on track and exactly what I was going to change, but decided it was way too much info to digest. So I deleted what I had typed and went with the very simple info above.

Here's a few laps from Pridmore a few years back so you can get a first person perspective. The track was completely repaved at the beginning of the season after being shutdown for 2 years, so our surface is much smoother now... too smooth!