Author Topic: K2/K5 Drag project (Read 108991 times)

NalleyRacing · « **Reply #550 on:** April 21, 2015, 05:53:36 AM »

You know me and Bill are in Frankie! Bill may just be crew chief at this event if he isn't fully recovered.. I'm gonna take my truck and trailer probably and try to bring my buddy Roland..

Lots to do in the next 8 weeks! I just learned John Hennessey(Hennessey performance) has a very nice 1/4 mile track at his shop about 76 miles from me! Gonna find out when test and tune is and try to make it out there once a week..

POPS 911 · « **Reply #551 on:** April 22, 2015, 06:58:19 AM »

MEMPHIS : You will love this track [ In MILLINGTON TENN. ] got to go to this one to visit the folks from the past IDBA and PRO-STAR events. You will love the DA 300-700' and DOWNTOWN BEALE ST. on Saturday nite is jumpin , but so are the cops......

NalleyRacing · « **Reply #552 on:** April 22, 2015, 07:15:46 AM »

I'm pretty excited about it only being a 10 hour drive as well! Seems like most of the crew will make it to this race. I just hope I can get enough track time in between now and then to help me feel a bit more comfortable. So much to remember at first.. Theres a fine sequence of events between staging and going through the big end. Burnouts are my weak point at this moment.

Jerry Rxman Griffin aka MuthaF'er · « **Reply #553 on:** April 22, 2015, 10:21:02 AM »

Quote from: dragracer on April 20, 2015, 10:30:00 PM

Whats the plan for Memphis guys?? Jerry? Trey? Wilbur? Bill??

Don't make me do this race solo fellas!!!

Probably not.

Plus N.C. is on freshman college move in weekend for my daughter at UK in Lexington, KY which would put me much closer on 4 wheels but I don't have a clue if that will involve me or her mother AND it's the beginning weekend of Bonneville which I had planned on attending and crewing.

I will probably be unable to go the anymore until the finals.

Trey,

Bill WILL be riding

You can't keep an old dog down!

NalleyRacing · « **Reply #554 on:** May 02, 2015, 06:14:11 AM »

Welp, I'm loading up the race bike to enter it in the Vintage Japanese Motorcycle Magazine, Texas show today. Hoping to see some other awesome old Hondas there as well! Also heading to Houston tomorrow for test and tune at the 1/8 track at HMP!

I'll post pictures as I can!

SBR-CB400F · « **Reply #555 on:** May 02, 2015, 06:43:13 AM »

Sounds like a good weekend Trey. Good luck at the test and tune, hope you run some good numbers

Adam

POPS 911 · « **Reply #556 on:** May 02, 2015, 09:11:01 AM »

TREY : Got a school question for you = Your on the 1320' track in 5th gear at 1000' and the shift light [ at top RPM'S for your motor ] is glowing shift me into 6th, but your bike is a 5 speed !! What do you need to change UP or DOWN to get your bike to have the shift light just coming on at the line or just pass ?? Seen a few float some valves at the big end by over revving the motor to get that win ticket for that last 320'. Another good reason to have rev limiter and a shift light.

POPS BK911

NalleyRacing · « **Reply #557 on:** May 02, 2015, 01:30:19 PM »

I noticed that my motor will pull 4th hard all the way to the end. The few times I actually hit 5th my MPH dropped by about 10 and my ET was slightly slower. I haven't had my motor dyno'd to see where the peak HP hits to set up a shift light. I was shifting roughly around 9k.

Hopefully I get plenty of seat time tomorrow to get that much needed data.

Bill/BentON Racing · « **Reply #558 on:** May 02, 2015, 05:05:00 PM »

Well its still the same, Show up, kick azz, have fun, and look out for idiot parents and unsupervised kids with RC cars!
Go back to doc on Monday. Treys coming, Wilbur maybe, Jerry no.Bill

SBR-CB400F · « **Reply #559 on:** May 03, 2015, 05:43:29 AM »

Thats easy POPS, put a 6 speed box in

Trey, you can use your shift light to find peak HP. Set it low at first, lets say 8 grand increase that by 100rpm or the smallest increment after each pass until your times start going backwards.

Adam

gschuld · « **Reply #560 on:** May 03, 2015, 08:50:13 AM »

Quote from: TreyAllen on May 02, 2015, 01:30:19 PM

I noticed that my motor will pull 4th hard all the way to the end. The few times I actually hit 5th my MPH dropped by about 10 and my ET was slightly slower. I haven't had my motor dyno'd to see where the peak HP hits to set up a shift light. I was shifting roughly around 9k.

Hopefully I get plenty of seat time tomorrow to get that much needed data.

Here's a question. I recall reading several old article accounts of Russ Collins geering up his early single engine bikes to run 1st through 4th only. Are there others who do this or is is better to gear to be at peak rpm at 5th at 1320?

TurboD · « **Reply #561 on:** May 03, 2015, 09:20:27 AM »

I favor using less gears when possible, Most always the bike (car) is quicker. When racing a street type bike (street tire and or no bar), a higher 1st gear is much more user friendly on the clutch hand. On my no bar Turbo Kawasaki's we would gear to only use 4 gears, overall drive was 17-29 if I remember correctly.

Bill/BentON Racing · « **Reply #562 on:** May 03, 2015, 03:25:23 PM »

I run 4 if I can. But gearing set for 5 right now. We used to just take 5th out if building one from scratch. Bill

gschuld · « **Reply #563 on:** May 03, 2015, 06:32:31 PM »

Quote from: Bill/BentON Racing on May 03, 2015, 03:25:23 PM

I run 4 if I can. But gearing set for 5 right now. We used to just take 5th out if building one from scratch. Bill

Actually, that's what RC did as well back then as well. Took 5th gear right out...

Especially for foot shifting, it's one less gear shift to mess up

.

George

POPS 911 · « **Reply #564 on:** May 04, 2015, 06:40:18 AM »

Tell me how you would get a consistent numbers foot shifting ? If you used a air or electric shift [ with a shift light ] with throttle all the way open and adjustable kill time on coils your number would be close, or why have they sold these shifting tools for year, is that not how MRE started out in the old days ? Dan Rudd [ MPS ] has sold many shifters for the modern bikes that make then win many rounds. Ask your self this = If you change to a bigger rear sprocket it will lower the gearing and make faster the acceleration .
TRUE or FALSE ?

TurboD · « **Reply #565 on:** May 04, 2015, 07:03:09 AM »

A direct answer to your exact question Pops is FALSE.

Actually there is not a correct answer to this question. Some vehicles Bike or Car, may respond well to a larger sprocket (lower gearing) while others will not. This broad type of question does not have a single answer.

I will say that one of the single biggest mistakes I have seen over my past 35 years of drag racing is guys trying to run too low of a gear ratio.

NalleyRacing · « **Reply #566 on:** May 04, 2015, 07:18:47 AM »

Since I started building bikes to race the question of gearing has always been a huge wonder to me. That being said im excited that it has finally gotten brought up in a drag racing scenario.

I have a huge assortment of gears to try. My current set up is 16/50 as Bill recommended. He has mentioned that we want a 3.2/1 or better ratio..

I have rear sprockets in 33,43,45,48, and 50.

I have Counter sprockets in 15,16, & 18

One question I have always had is what would happen if the bike was geared extremely high. Say 15/43 for instance. Would it be too much strain on the transmission trying to pull that gearing down the track?

gschuld · « **Reply #567 on:** May 04, 2015, 07:36:31 AM »

Pops,

I'm not interested in derailing this thread, and I understand that an air or electric shifter with a shift light is hugely important to bracket racing consistency. It's just not my main priority personally. My priorities and Trey's differ in this regard so I'd rather concentrate on Trey's needs as this is his thread. Sorry for the thread drift...

Naturally, going to a larger rear sprocket will lower the gear ratio and increase the torque the engine can deliver to the rear tire in first gear. This, as Turbo mentioned, does not necessarily guarantee an overall performance improvement at the track. I know what you are getting at though. For Trey's purposes, as he currently has a very modest power output and presumably a fairly easy time getting the power he has available to the track traction wise, than yes, his initial acceleration would very likely improve with a slightly larger rear sprocket. Clearly he can't go beyond his safe max rpm in 5th by the end of 1320 though.

TurboD · « **Reply #568 on:** May 04, 2015, 07:38:02 AM »

When gearing a vehicle Bike or car for drag racing, a number of factors play into picking, testing and ultimately landing on the best ratio for the application.

Factors like power level and power band of engine, launch rpm, weight, number of gears, tires/traction, and even riding style all figure in.

Most often if you focus on getting the best 60 foot times, everything else will generally fall into place. A too low of a ratio can hart you just as bad as a too high of a ratio.

A 15-43 is a 2.86 ratio. These bike came stock with 17-48 2.82 and 18-48 2.66.

gschuld · « **Reply #569 on:** May 04, 2015, 08:03:41 AM »

Trey,

I am certainly no gearing expert regarding dragbikes, but here are some basics.

Your current gear ratio at 16/50 is (3.12). If you want to lower your ratio, your next lower option available to you on hand would be 15/48 (3.2). The next step higher would probably be 16/48 (3.0). If you go 15/48, you will be pulling a little more rpm at the big end of the Track and ...should ...have more acceleration off the line. The opposite with going higher to 16/48. Doing 15/43 would likely reduce your acceleration noticeably down low and barely put you in 4th gear at the big end. Not the direction you want to go I'd think. I'd lean toward 15/48 and see if your 60ft improves and see exactly where your rpms are in 4th at the end of the track. No need to throw a stock rod at the end of the track by over revving.

kmb69 · « **Reply #570 on:** May 04, 2015, 11:08:43 AM »

Trey, Did you make it to HMP yesterday?

TurboD · « **Reply #571 on:** May 04, 2015, 11:58:46 AM »

There is so much more that comes into play during a launch then some simple mathematics.

If you have a ratio that is too low, 1st gear will be simply useless. You will not have enough 1s gear to properly slip the clutch, and with a fast bike the rider will not be able to get his foot to the shifter fast enough to shift. If 1st is too low (short), you will barely be rolling before losing time shifting.

The main and most important thing when launching a street tire and or no bar bike is good clutch and throttle control. To be fast and obtain the best 60's a rider has to be very good with the clutch and throttle, this is something that is hard to explain in person let alone over the internet. This is something that is natural to some, some racers with practice learn it and some racers never understand how to achieve this. last week I had a racer with a warmed up Hayabusa, say that he has spending more in an effort to go quicker. I asked what his 60's where, and he replied 1.8's. I located his problem pretty quickly. Lol

NalleyRacing · « **Reply #572 on:** May 04, 2015, 01:16:51 PM »

No Keith I didn't get out to the track after all. Had a busy day that ended up taking most of my evening.

That being said I found a really nice 1/4 track near me in Little River Texas that offers a test and tune. I think its a IHRA sanctioned track.. I am going to check it out Friday if the T&T is weekly.

I have had alot of trouble bogging on the line and I have a feeling my gearing needs an adjustment. I am comfortable with my clutch and throttle but it seems like my bike never launch's like I feel it should.

I am going to do a few test launchs in my neighborhood later and retest the air shifter. Its just about dialed in as well.

gschuld · « **Reply #573 on:** May 04, 2015, 03:00:41 PM »

TurboD,

I understand where you are coming from and I am enjoying, and appreciating your input. I think it's safe to say that the faster the bike the more it gets complicated. Trey's situation would presumably be a bit simpler. He is very new to this and is trying to get as much as he can out of basically a dead stock cb750 chassis, weight, and power wise. We are talking starting out in the 15s and trying to get well into the 13s. No doubt, getting a good 60ft is his first priority. I just want to make sure we are discussing his situation specifically and not getting side tracked with concerns beyond the capabilities of what he is currently riding. If I am misreading your thoughts let me know. I'm not trying to be difficult.

On a personal level, I'd be very happy to have a separate thread regarding setups, gearing, techniques, etc geared toward 10 to 11 second capable dragbikes. I am in somewhat the same boat as Trey, just starting the drag thing but with a much lighter, more powerful bike. I need all the help I can get...

George

Jerry Rxman Griffin aka MuthaF'er · « **Reply #574 on:** May 04, 2015, 03:32:20 PM »

Quote from: TreyAllen on May 04, 2015, 01:16:51 PM

No Keith I didn't get out to the track after all. Had a busy day that ended up taking most of my evening.

That being said I found a really nice 1/4 track near me in Little River Texas that offers a test and tune. I think its a IHRA sanctioned track.. I am going to check it out Friday if the T&T is weekly.

I have had alot of trouble bogging on the line and I have a feeling my gearing needs an adjustment. I am comfortable with my clutch and throttle but it seems like my bike never launch's like I feel it should.

I am going to do a few test launchs in my neighborhood later and retest the air shifter. Its just about dialed in as well.

Trey,

My take is the bogging is more of an issue with your left clutch hand and the minimal horsepower your engine is NOW producing while trying to spin the rear tire on that sticky #$%* you can hardly walk on. MUCH different than normal asphalt. Your gearing is ALREADY 1 to 2 down up front and 2 up on the rear! You saw what happened that one run when it did break loose. I'd like to see what gear and rpm you are at at the 1320 with the 16/50.

News:

Author Topic: K2/K5 Drag project (Read 108991 times)