First time on the dragstrip!

[Rob S.]

I had not understood that ET timing starts on physically leaving the line, not the green light.

Me neither. Doesn't that render the reaction time irrelevant? Even the green light irrelevant? If the clock doesn't start till you move, why even pay attention to the green? Why would you be disqualified for leaving early (red lighting)? At what point would you be flagged for "delay of game"?

Rapidray, could you clarify?

[Baatfam]

Me neither. Doesn't that render the reaction time irrelevant? Even the green light irrelevant? If the clock doesn't start till you move, why even pay attention to the green? Why would you be disqualified for leaving early (red lighting)? At what point would you be flagged for "delay of game"?

Rapidray, could you clarify?

Remember, the strip is designed for racing, not just how fast you go. First to the finish line wins.

When the light turns green, that's when the race officially starts. The one who starts first, (better reaction time), gets a head start. An advantage. But leave too soon, and lose. Red light. (I am leaving out human and vehicle reaction time. You really need to go before the green to get a good RT. That's what the yellow lights are for, to tell you when the green is coming.)

ET starts when you leave the staging beam and ends when you break the beam at the finish line.

With a faster reaction time (Green to leave) you could win with a slower ET.

Let me know when you are ready to discuss bracket racing, because that's where it gits fun.

And of course Mr. Google is still open:

https://www.us131msp.com/drag-racing-101/

https://www.onallcylinders.com/2012/06/22/bracket-racing-101-learn-basics-then-get-out-race/

https://www.youtube.com/results?search_query=bracket+racing+explained

[stetracer]

It will change you Et and reaction time depending on where you stage in the beams. Shallow staging will slow your reaction time but quicken your Et. Deep staging will quicken your reaction time but increase your Et. I personally prefer to deep stage. Most shallow stage. I use a delay box so it really doesnÂ’t matter where I stage. But for me Deep staging helps me be more consistent on my reaction time. Deep staging does tend to irritate some racers.
I use a 2-step launch limiter with a crossover delay box and a slider clutch with the auto shifter.
I am thinking about naming my pro Et bike “ Flicker” because I can make the top bulb flicker on and off

[stetracer]

OK! Air shifter is nearly working now. I'm not 100% certain, but it looks like the problem is either with the pushbutton switch on the handlebar, or the wiring between the button and the solenoid for the shifter. I cut the solenoid activation wires back by the sidecover, then connected one to positive, the other to ground - the cylinder fired just like it should.

Disassembling the switch for inspection I noted one of the three leads had separated from the switch housing. I'm not sure if that's the cause of the problem, but will dig a bit deeper later this week. Rather than try to fix that particular switch I'll probably just grab a universal pushbutton kill switch out of my spares boxes and wire it up. I'm sure I can find a replacement microswitch for the Pingel button assembly, but that'll take some sleuthing.

Regardless, we're one step closer!

how are you testing your shifter? You need to disconnect your shift lever to test it.
I have lost quite a few races using cheep switches. A lot of racers use these. https://www.mpsracing.com/products/MPS/Probutton.asp

This is the the switch I use.

https://grothusdragbikes.com/collections/frontpage/products/dominator-button-bracket

[patrino]

Good advice, stetracer, thank you!

Yes, I disconnected the cylinder from the shift shaft prior to testing, no sense beating up the shift forks & transmission internals. I talked to the folks at Pingel yesterday (great customer service, by the way!) and they assured me the cylinder could be fired without any resistance.

Here's the switch I'm running, but bear in mind it's probably 25+ years old: http://www.pingelonline.com/handleba...ar-control.asp. Thank you for the recommendation and options.

[stetracer]

Patrino
if you a Facebook member then join Dragbike Trader group and GS & KZ Dragbike Part:BUY&SELL group

[Baatfam]

Patrino
if you a Facebook member then join Dragbike Trader group and GS & KZ Dragbike Part:BUY&SELL group

Does Dragbike.com still have a forum? It was a good forum years ago.

[kingofvenus]

We'll be at 131 in june for a nhdro race....

[patrino]

Jets have already arrived! Assuming the weather holds, hope to get back to the track the evening of the 24th.

stetracer, thanks for the Facebook tips. I requested permissions for the Dragbike Trader group, and will do so for the GS / KZ trader group, too.

[red1100]

How is the racing handled during covid?

[patrino]

A few things, folks had their temperatures checked at the gate, they limited attendance to 100 vehicles, with one driver and one helper each, max. Masks were required for folks not immediately competing. Enforcement of the above policy amounted to stern reminders over the PA system, it seemed to be.

[patrino]

Good news! Got the air shifter working, tracked the problem down to a disconnected lead at the handlebar button.

From the todo list:

* bench-test air shifter / identify cause of problem
--- see above
* find spare shift shaft
--- found a couple, but probably (hopefully?) don't need; bike shifts great with sprocket cover off, suggesting the shifting problems come down to a bound-up sprocket cover. I tried the cover with only three bolts in (including the doweled hole) and it shifts pretty good. Going to try that.
* extend pegs
--- I turned a couple ~1" spacers in the lathe, now need to get some longer bolts to mount the pegs
* change low-speed rpm pill
--- DONE
* test operation of high/low ignition switch, on clutch
--- tested it, confirmed it works well
* install 140 mains
--- DONE
* bush shift shaft hole, in sprocket cover?
--- probably (hopefully) not necessary - see above about shifting
* find extension cord splitter
--- FOUND IT
* inspect plugs
--- not done yet
* change oil
--- no big chunks, but lots of fine aluminum in the oil. Changed the filter too.
* install carb float bowl drain lines (to make rejetting easier and less messy)
--- not done yet
* move Keihin jets into their own box
--- still need to buy one

[patrino]

Progress - did a 10.755 at 131 mph last night, with plenty more to give from both me and the bike. Got popped for noise twice (max 103 dB at my local track) and sent home, so top of the todo list is quieting things down.

More detail soon!

[steve murdoch]

Impressive!
I knew they have noise levels at track days, it never occurred to me they would have them at the strip.

[Greg B]

Progress - did a 10.755 at 131 mph last night, with plenty more to give from both me and the bike. Got popped for noise twice (max 103 dB at my local track) and sent home, so top of the todo list is quieting things down.

More detail soon!

Heh. I figured it’d be pretty loud with no baffle.