A few help questions. First day at track.

[twinvipers]

Took the Busa to the track yesterday for the first time. Bike has PC,Muzzy and is lowered and strapped. Also has clutch mod and One tooth down in the front. Bike made 169RWHP at Lee's this week. Rider weight is about 200.

Most passes were 10.0X at 141-144 with 60' times in the 1.7's. Did One 1.66 60' but had to get out of that pass.

Best pass was 9.98@143 with a 1.72.

My issues and questions are:

1-everytime I launch I start at the tank and get pushed back into the hump and it made it very hard for me to stay settled and shift into second.

2-The bike would not keep the front wheel on the ground at all in first gear making me have to shift into second way too early and could not open the throttle all the way in first.

3- Had very bad tank slap a few times while coming down from the first gear wheelies.

I was foot shifting with the throttle wide open and using the clutch.

Thinking of a drag seat and an air shifter. Also thinking of putting the stock sprocket back on the front.

Any thoughts/help would be greatly appreciated.

 

[dragonbusa]

First time to the strip you did dam good, most guys dont crack the 9s first time out. to keep the front down get you some exstintions, and the drag seat will help alot. air shift is great to, I"m running a muzzy air shift and it works great. for me an on board compressor is the way to go.takes all the head ache out of it. no worrys about the co2 leaking down or finding some one to fill your bottle. oh and seat time, no one can talk you through seat time.

 

[twinvipers]

Thanks for the advise

Are there different options for drag seats ?

I feel like if I could have stayed in the pass with the 1.6 60' I could have gone 9.7x

I was told the air shifter will pick up about 2-3 tenths and about 4-5 mph.

 

[Professor]

You are on the right track. Congratulations!

1) drag seat will help a bunch. A quick fix is to take an old seat and pull off the cover. Use an electric carving knife and trim most of the foam off of it and put the cover back on it.

2) You may need to stiffen the compression valving on the rear shock a bit. Is it staying down the first 60' and then coming up? If you slip the clutch and roll the throttle you should be able to contol the front wheel during the launch. It should not do much more than hover after that.

3) change the oil in you steering stablizer to a heavier weight. Even better if it is in your budget, install an aftermarket unit like a GPR. I have never had mine shake coming down from a wheelie with my GPR.

The drag seat will help a bunch. Not only will it hold you in place better, it will also lower your body weight in the bike (lower center weight)

It takes a bit of time on the shifts, but I was only using the clutch on the 1-2 shift. a) to ensure that more difficult shift was correctly made to avoid transmission damage b) to smooth up the change to keep the front wheel down. The 2-3 and 3-4 shifts were done without the clutch. preload the shifter with the toe and quickly roll the throttle back about 30-40% and right back to full and it will slide right in there. Wide open and using the clutch can be very hard on the clutch plates. More so in the higher gears.

On the air shifter, I prefered Co2 over the compressor but both work well. I had three bottles and put in a fresh one for each race day. The last year, I used the very small disposable bottles. I never had a leak problem, but I replaced all my fittings with much higher quality one than what was supplied with the kit.

Like Dragonbusa said.... SEAT TIME is the best fix.

 

[twinvipers]

You are on the right track. Congratulations!

1) drag seat will help a bunch. A quick fix is to take an old seat and pull off the cover. Use an electric carving knife and trim most of the foam off of it and put the cover back on it.

2) You may need to stiffen the compression valving on the rear shock a bit. Is it staying down the first 60' and then coming up? If you slip the clutch and roll the throttle you should be able to contol the front wheel during the launch. It should not do much more than hover after that.

3) change the oil in you steering stablizer to a heavier weight. Even better if it is in your budget, install an aftermarket unit like a GPR. I have never had mine shake coming down from a wheelie with my GPR.

The drag seat will help a bunch. Not only will it hold you in place better, it will also lower your body weight in the bike (lower center weight)

It takes a bit of time on the shifts, but I was only using the clutch on the 1-2 shift. a) to ensure that more difficult shift was correctly made to avoid transmission damage b) to smooth up the change to keep the front wheel down. The 2-3 and 3-4 shifts were done without the clutch. preload the shifter with the toe and quickly roll the throttle back about 30-40% and right back to full and it will slide right in there. Wide open and using the clutch can be very hard on the clutch plates. More so in the higher gears.

On the air shifter, I prefered Co2 over the compressor but both work well. I had three bottles and put in a fresh one for each race day. The last year, I used the very small disposable bottles. I never had a leak problem, but I replaced all my fittings with much higher quality one than what was supplied with the kit.

Like Dragonbusa said.... SEAT TIME is the best fix.

How do I stiffen the compression valving on the rear shock ?

Will it help to lower the rear to the last hole on the links

Should I lower the front with a new triple clamp or is the strap OK ? I have it pulled down to almost touching the front fender.

I will order the seat this week. Are there many seat choices ?

Thanks for the help.

 

[Professor]

There is a valve on the upper part of the shock. Try 2-3 clicks from where it is and see if there is a difference. But before you do that… check the rear sag to make sure the preload is right.

Lower is better! I lower the front with a custom tree. Then I strap it from there.

Take a look at the seat Jesse Gatlin is offering. IMO it is one of the nicest built ones on the market, pricy however. The Catalyst and some of the copies is nice, but you need to use a stock bracket from a donor seat. That only attaches to the front. The rear lies on the bodywork. I was too big for a Gatlin or standard Catalyst and used a Catalyst heavy hitter version. I built a custom rear bracket to strengthen it and it lays on the frame rails instead of the bodywork. There are some pictures on the site of mine.

An air shifter will help with consistency making each shift the same and taking rider error out of the picture. Don’t expect big number changes unless you are really screwing up. I saw no difference in MPH and maybe a tenth, but less if I remember right. The runs numbers from high to low did tighten up.

 

[twinvipers]

OK

I am going with the seat. Lowering tree.

Sorry for the dumb questions but how do I check rear sag/pre=load before changing the settings ?

 

[twinvipers]

Are the Tobin seats any good for launching ?

 

[twinvipers]

Is there a way to extend it just an inch or Two ?

 

[Professor]

OK

I am going with the seat. Lowering tree.

Sorry for the dumb questions but how do I check rear sag/pre=load before changing the settings ?

Here is a thread that has some good info on sag/preload

https://www.hayabusa.org/forum/maintenance-do-yourself/89876-jinkster-attacks-suspension.html

 

[Professor]

Are the Tobin seats any good for launching ?

The Tobin and the one Soupy (board sponsor) makes are built from a stock seat pan. They are much better for dual use. The Gatlin or a Fiberglass/Carbon Fiber drag pan will put you lower, but you don’t want to ride on the street with the one. I don’t mind swapping so I have 3 stock for riding, Corbin for long rides, and a drag pan for the track.

Link to soupys seat

 

[Professor]

There are some extensions that work at 2-6", maybe even 2-4". I chose a custom swingarm for a more stealth look.

The one in the back is abour 7/8" over stock. The front is a closer to 2.25-2.75"

 

[Professor]

What year bike do you have. Some of the aftermarket choices may be a bit more limited on the 08-09 models.

 

[Mr Bogus]

check your grip.... every time I have managed to make the bike shake (tank slapper stuff) I have found my grip is not the same left/right.. (is interesting when the front tire comes off that ground at 150mph let me tell you.. )

you will probably notice the bike wants to go left or right as well while the front tire is off the ground.. GPR will stabilize the problem but it might just be a bandaid for the underlying cause.. The front wheel is probably turned a bit from center when it touches down and is causing the shake.. (need some good video to see if that is the case)

seat time seat time seat time...

 

[twinvipers]

The Tobin and the one Soupy (board sponsor) makes are built from a stock seat pan. They are much better for dual use. The Gatlin or a Fiberglass/Carbon Fiber drag pan will put you lower, but you don’t want to ride on the street with the one. I don’t mind swapping so I have 3 stock for riding, Corbin for long rides, and a drag pan for the track.

Link to soupys seat

Will the Tobin help at the track ?

There are some extensions that work at 2-6", maybe even 2-4". I chose a custom swingarm for a more stealth look.

The one in the back is abour 7/8" over stock. The front is a closer to 2.25-2.75"

Which one is on the bike in the picture ? Looks like what I want. Where do I find a swing arm like that ?

What year bike do you have. Some of the aftermarket choices may be a bit more limited on the 08-09 models.

2002

check your grip.... every time I have managed to make the bike shake (tank slapper stuff) I have found my grip is not the same left/right.. (is interesting when the front tire comes off that ground at 150mph let me tell you.. )

you will probably notice the bike wants to go left or right as well while the front tire is off the ground.. GPR will stabilize the problem but it might just be a bandaid for the underlying cause.. The front wheel is probably turned a bit from center when it touches down and is causing the shake.. (need some good video to see if that is the case)

seat time seat time seat time...

thanks
I'll take notice

 

[sean06]

Congrats on the 9's Thats great for your first time out.

Looks like you have gotten a lot of good advice here already. Yes the tobin will help its what im running on my bike. It looks great, like it should have came on the bike, and keeps you close up to the tank when launching and gets you lower (and doesnt scratch your tail piece to hell). Here is a pic of mine

And unless you shift really slow an airshifter wont improve your times, but it will help make you more consistant. I can run the same times footshifting or on the shifter. And for the fastest shifts you dont want to use the clutch ever. just role off the throttle and slam the next gear, its the same thing that happens when you use an airsihfter(it just kills the motor for a split second).

And if your at stock length Id go back to stock gearing, it will help keep the front end down.

 

[sean06]

Take a look at the seat Jesse Gatlin is offering. IMO it is one of the nicest built ones on the market, pricy however. The Catalyst and some of the copies is nice, but you need to use a stock bracket from a donor seat. That only attaches to the front. The rear lies on the bodywork. I was too big for a Gatlin or standard Catalyst and used a Catalyst heavy hitter version. I built a custom rear bracket to strengthen it and it lays on the frame rails instead of the bodywork. There are some pictures on the site of mine.

.

Could we get a link to where those pics are? id love to put the drag pan on my bike, but I didnt like the way it sits on the tail. Do you have any pics of what you did?

thanks

 

[twinvipers]

Congrats on the 9's Thats great for your first time out.

Looks like you have gotten a lot of good advice here already. Yes the tobin will help its what im running on my bike. It looks great, like it should have came on the bike, and keeps you close up to the tank when launching and gets you lower (and doesnt scratch your tail piece to hell). Here is a pic of mine

And unless you shift really slow an airshifter wont improve your times, but it will help make you more consistant. I can run the same times footshifting or on the shifter. And for the fastest shifts you dont want to use the clutch ever. just role off the throttle and slam the next gear, its the same thing that happens when you use an airsihfter(it just kills the motor for a split second).

And if your at stock length Id go back to stock gearing, it will help keep the front end down.

Thanks man

Your bike is absolutely beautiful. If you ever want to sell it PM me.

 

[sean06]

Is there a way to extend it just an inch or Two ?

After making a bunch of swb passes and now being extended I wouldnt just add an inch or two. It wont make a big enough difference for the time and money. Adding 4" to my bike only helped knock 3 tenths off my time. So id figure an inch or two wouldnt be much more than 1-1.5 tenths. I can only add 4" because of the tail on the gen2. If I had a gen1 I would run my bike at 64" the front will still want to come up even at that length. Im at 62 and still fight wheelies all the way through first.

And to your other question get the bike as low as you can before you run into ground clearance issues. The lower the less it will want to wheelie

 

[twinvipers]

OK

I am going with a seat,lowering the front with the Triple,lowering the rear to the last setting on the dog bones,stock front sprocket and a lot more seat time. I will also foot shift it with no clutch.

Thanks for all the help guys. I will keep you posted.

Will it help to run without an air filter ?