Topic: Race at Rockingham Dragway- big bucks

[gschuld]

The handheld Altronics "performance predictor" model like in that link?

George

[dragracer]

Frank, the point I'm trying to make about jetting is that the jets don't come in small enough increments to justify small atmospheric changes. Which style Mikuni jets are you using, the hex head or the round-head reverse flow?

Flat slides use the large, round heads.

[dragracer]

The handheld Altronics "performance predictor" model like in that link?

George

Yes. That's the most economical and effect handheld that most sportsman racers use for ET predictions. Don't get me wrong, we do check weather conditions periodically through the day via density and corrected altitude searches. You then make logical decisions on tune UPS and ETs based on experience. But there's nothing better than a device that actual takes all that data, coupled with your own bikes performance and then predicts ET adjustments for you as the conditions change throughout the day. Instead of a manual log book, its in the handheld and can be downloaded if necessary for further use.

[Jerry Rxman Griffin aka MuthaF'er]

But we're still talking carbs here. Your laptop will not easily do anything for carbs. That .001 can make a difference.   

[dragracer]

That's true Jerry. But the predictor can get you in the ballpark based on weather conditions. With historical data, even with improperly tuned carbs, you could come closer to the dial in than educated guessing like I do now. Lol. Its just another tool to move you closer to the winners circle. Weather stations are critical to bracket and index racing where consistency is key.

[scottly]

Frank, once again, my limited experience is with VM round-slides, and there is an 8-9% difference in fuel flow between each jet size with the reverse flow jets. You can't compensate for a 1-4% atmospheric change with a main jet, but you can predict the outcome.

[dragracer]

I can say that the jetting changes I made for this event did allow for more consistent ET' s between the daily temperature variations. I'm satisfied with the results thus far. Again, I'm more proficient in Lectron carb tuning for various weather conditions so I applied the same reasoning to the flatslides and got decent results. Your pilot jet / main jet chart was helpful in my decision making process. I appreciate your input as it forces me to think through a proper course of action.

[jweeks]

When I first flew down to Rockingham to help Sam and Bill, I asked around for someone who knew the current DA. When no one had one, I brought my own unit down to the next meet at Valdosta. A big problem with using the prediction function is the accuracy of the data being used. Any abnormal inputs will alter the estimate. So, if you get out of it on the top end, you can't use that input. If the DA drops and you rejet, the old data will be off some for future runs. That's why I still like the log books, which gives you quick access to previous runs under similar conditions. It has worked well for me over the last 15 years. My current meter is about 5 years old. It's been back for recalibration once to the factory. They drift some on DA over time. I think that Bill will confirm that I still remember a little about ET predictions. We dialed Sam for a 2 to 4 hundredth cushion. I was a little further off at Rockingham, but didn't have any data records to use. The only time that Sam got dialed really tight was when we were called up to the lanes and went right out onto the track without the time to go back to the trailer to find dial in numbers. The 12.4 dial I thought would be a first round breakout; with a buyback likely, I didn't worry too much. Sam got a 12.403 and a round win. I didn't have enough confidence with the limited data to dial it much closer than .02. If you have the data and the confidence in the bike's consistency, you can run .012 over in the first round and up your dial-in for the second round by .01 and run .001 over for that pass like I did in a Prostar meet. When you're dealing with thousandths of variations, you will go rounds. Yes, I'm talking about my Hondamatics. The clutch CB750 bikes just can't repeat that well. I'll post some time slips next season to support my beliefs. Many of the Hondas running at Valdosta cut good reaction times, but didn't last too many rounds. Either the driver didn't dial it right or mechanical issues affected the run that put them out of the event. Building it just before the race, going to the race without practice, is only good for a timeslip not a lucky win light. When you can consistently run sub .05 packages, you will become a serious threat to win some $$

[Bill/BentON Racing]

Yes too all you wrote. My plans for  a better 2015 went down the drain in April, making love to the asphalt sans protection not recommended,  especially for old timers! 2016 plans are being put into place. 23 passes for the year not going to tell you a lot, especially over 3 events, didn't run Memphis. Next year I plan on using Commerce to practice a bunch. I believe someone  (Frank) will put the A/SS record under 10.5. Could be much closer also.  G'luck and Happy Thanksgiving. Jon ,you can dial my bike any time...ok, except if I'm running you!! Which I sure hope happens in 2016 even if it's just qualifying. Bill

[dragracer]

Jon, you are correct about numbers not being repeated at this last race. A few of my runs were all over the place. A little bit of that was from me trying to adjust to the motors response to the new jetting. The bigger pilots seemed to allow the bike to rev quicker given the throttle position. It threw off my launch. Nevertheless, I finally got a handle on things. Next season should be different. We'll see. Still shooting for the top ten finish and now pushing for a race win. Lofty goals for an sohc but you have to believe in yourself if you want to make a goal turn into a reality.

[Jerry Rxman Griffin aka MuthaF'er]

speaking of which, where did everyone place?

[POPS 911]

A womp w/sandbagging can be a win ticket = watched more than a few winners at MAN CUP VALDOSTA on live feed go many rounds. They had their right hand on the PREDICTOR !!!!!

[754]

If your RT is lower than your competitors, most of the above still wont get you a win ...correct ?

[madmtnmotors]

If your RT is lower than your competitors, most of the above still wont get you a win ...correct ?

Wrong. The above discussion (IIUC) is about how to more accurately predict your E.T. based on real time (i.e. constantly changing) weather conditions at the track. If both riders predict their E.T. correctly (or to within the same margin), then the victory would indeed go to the one with the lower R.T.

Which is as it should be.

Of course this observation implies that I have understood the discussion up to this point!   

[754]

Exactly my point, with the best weather station , and ET prediction, still wont get you wins if your RT sucks..
 Just in case anyone gets the impression that money  spent on goodies will help get the win ..its only half the battle..

 So if you RT is bad, you better work on that...as much as the rest..

[madmtnmotors]

Exactly my point, with the best weather station , and ET prediction, still wont get you wins if your RT sucks..
 Just in case anyone gets the impression that money  spent on goodies will help get the win ..its only half the battle..

 So if you RT is bad, you better work on that...as much as the rest..

LOL

Yeah, if you can't cut a good light, you might want to reserve your efforts to serving on the pit crew and/or spectating!   

[dragracer]

Alright gentlemen,

Find below a time slip from eliminations at the Man Cup race. I was in the left lane. As you can see, I had a perfect reaction time, yes, it was triple zero's. Now look at my dial in and then my ET. I can tell you that I didn't chop the throttle. I did win this round. However, if my opponent, that had a .030 reaction time had just looked back and cut gas, he could easily have won the round. Why?? Because in spite of my better reaction time, my dial in was way off the mark- I simply couldn't run the number. I only won because he broke out- he got there first with a substantial margin to have slowed down before I caught him.

This is a prime example of missing the dial in, even though I had the better reaction time. I was just lucky due to his mistake. A more experienced rider would have sent me packing.

Now, lets figure out what went wrong on me not running my ET. If you look at the ticket before this round, 5:42pm, you'll see I dialed in a 10.55 and ran a 10.54. I made a full pass because I knew my opponent redlighted. I ran .01 under my dial. I stayed with that number for the round at 9:58. When you look at the incremental numbers, you'll see on paper what caused me to not run the number. What you will not see is that the weather had also changed for the worse. Weather changes do affect dial in's on carbed bikes. This may have contributed somewhat to my bike slowing down but the 60' times are the main factor. A weather station would have allowed me to more accurately make adjustment if the data required it.

Again, consistency is the name of the game at winning  in ET racing. In my case this round, it was pure luck and a perfect reaction time that pressured the guy to never lift.

[754]

Can you change your dial thru the day.. Up here we could but only one way....  I never liked sandbagging..just run full out .

[dragracer]

Can you change your dial thru the day.. Up here we could but only one way....  I never liked sandbagging..just run full out .

Dial in's can be changed from one round to the next in any direction you choose.

[dragracer]

Here is an interesting ticket showing reactions and along with a double breakout. I left the line late and had to chase him across the stripe but we both broke out. A little more for me than him, dammit!! The air was really good in the morning but got worse throughout the day. I was also adjusting my launch rpms and clutch release to the wheelies that developed after rejetting the pilots.