Jump to content

The 1st Gear Launch, All The Secrets!


SlowerThanYou

Recommended Posts

As some know we are advocates of the 1st gear launch. This is primarily necessity for the asphalt, the primary surface we run. We decided to hill shoot in early 2009 & race 300' in late 2011. We were told by most we needed to start in 2nd gear for them surfaces. Our experience & transmission (1-4, manual 5 & 6) led us to follow what we knew.

 

Anyway, we get questions about using 1st gear launches in conversation(s) & PMs. I can only offer an opinion on the one to use, because we have never used a 2nd gear launch.

 

Here's the number one thing I would consider in what gear to start in; overall weight, both rider/race ready quad. Somewhere around 480 lbs. & above is where I would consider using 1st gear. I only say that, because that's our lightest overall weight. It still may be advantageous to use 1st gear at a lighter weight. In my opinion 480 lbs. is the line that you need to make that decision.

 

Another thing people are worried about is the transmission gearing spread. The 2-3 ratio has less of a spread, that equates to less of a rpm drop. It's just the opposite for the 1-2 ratio. Can this be overcome with other tuning, we try to.

 

This is just a couple areas I'm sharing my thoughts/opinion(s) on this subject. I forgot, LOL! with all the secrets BS.

Link to comment
Share on other sites

it seems like when i first gear pull its runs through so fast an i have to shift....on the other hand i dont run an overide because i just have a trail bike that i throw paddles on an take to the dunes, with no overide is it still better for first gear launch

Link to comment
Share on other sites

thanks for starting this thread. im still trying to see the advantage though when the advantage is clear with the 2nd gear launch like you said the gear spread is shorter.

in my experience my faster runs and 60's would always be with a 2nd gear launch.

clutch tuning of course seems to be the only way I can pull 2nd gear.

maybe changing sprockets out and setting it up for 1st gear launch is something I should try?

seems to me that there is more than one way to skin a cat right.. ha

im curious if your running through 6th gear in 300ft starting in first gear. if so it seems to me there would be a lot more room for driver error with all that gear changing going on.. im running a 1-5 override and gear to pull through 5th by the finish

Link to comment
Share on other sites

it seems like when i first gear pull its runs through so fast an i have to shift....on the other hand i dont run an overide because i just have a trail bike that i throw paddles on an take to the dunes, with no overide is it still better for first gear launch

 

With the right set-up, as anything. You could make it work IMO.

 

thanks for starting this thread. im still trying to see the advantage though when the advantage is clear with the 2nd gear launch like you said the gear spread is shorter.

in my experience my faster runs and 60's would always be with a 2nd gear launch.

clutch tuning of course seems to be the only way I can pull 2nd gear.

maybe changing sprockets out and setting it up for 1st gear launch is something I should try?

seems to me that there is more than one way to skin a cat right.. ha

im curious if your running through 6th gear in 300ft starting in first gear. if so it seems to me there would be a lot more room for driver error with all that gear changing going on.. im running a 1-5 override and gear to pull through 5th by the finish

 

Is the advantage(s) clear? To me the advantage is the quickest possible 60' time. Carrying forward to the best possible ET. We, have had great success by doing that. I hate doing comparisons, but I think it's needed to prove this point.

 

Take our old set-up:

443cc race gas cub

Rider's 180 - 210 lbs.

Stock Frame, 310 lbs. with front brakes

 

1st gear launch

It pulled 1.31-1.34 60' times on both sand & asphalt.

 

Take another very fast & proven set-up:

643cc on alky

Rider(s) I'm surely less than 180 lbs.

Custom chromoly frame 250 lbs. or less guessing and no front brakes 

 

2nd gear launch, pretty sure?

I saw 3 very impressive 300' time slips of this combo, 1.34 - 1.37 60' times.

 

One bike clearly at a disadvantage & the other a well set-up sand chassis. You can make your own conclusions!

 

Now, with your own experiences. Use what works for you, that's all that matters.

 

Clutch tuning is key in whatever gear you launch in!

 

Changing sprocket ratios is needed between the 2 different launch gears. We ran a 17 up front and anywhere between a 39-43 rear sprockets.

 

There's many different ways to do things, as with most things in life.

 

Last, but not least. We only use 1-4 gears making 3 shifts. As far as I know with the 2nd gear launch. They are using 2-5 gears making the same 3 shifts.

 

Take it for what it's worth.

Link to comment
Share on other sites

your right, what I was referring to was on paper it SEEMED clear.. so cant you change sprockets to achieve the same gear ratio's from starting gear either 1st or 2nd to be the same? so from there would a closer gear ratio be able to pull 'easier' to the next? maybe with my smaller motor it is and maybe with a larger motor like yours it likes/handles the jump in ratio better? this would equate to a better et in theory but im still trying to grasp the advantage in 1st gear launch for 60'..

 

your referring to 2 different bikes in your comparison when they most likely have different clutch setups as well as tire and arm length ect...    

 

now I need a good tnt day at the track because I am really wanting to do some comparison..  thanks for sharing as always.

Link to comment
Share on other sites

your right, what I was referring to was on paper it SEEMED clear.. so cant you change sprockets to achieve the same gear ratio's from starting gear either 1st or 2nd to be the same? so from there would a closer gear ratio be able to pull 'easier' to the next?

 

Changing the sprockets, can make the effective ratio the same for either launch ratio. You still have to deal with the transmission ratio spread between the two different 1st-2nd or 2nd-3rd launches.

 

maybe with my smaller motor it is and maybe with a larger motor like yours it likes/handles the jump in ratio better? this would equate to a better et in theory but im still trying to grasp the advantage in 1st gear launch for 60'..

 

your referring to 2 different bikes in your comparison when they most likely have different clutch setups as well as tire and arm length ect...    

 

 

You keep comparing your bike to my bike. A 22cc difference is not much! 421s are one of the best builds out there. The majority of Builder's know how to get the most power per cc out of them.

 

Plus, if we use your 2nd paragraph in the quote. You shouldn't be comparing our 2 different set-ups.

There's a reason I provided that other comparison!

 

now I need a good tnt day at the track because I am really wanting to do some comparison..  thanks for sharing as always.

 

Now, if you go to the Lock-up Tuning Thread latest posts. You will see where phunt is doing testing with the different launch gears & the clutch. Plus, he's using a 421 cub. 

 

Here's a recommendation, there's something to be learned by these different comparisons. It's almost impossible to get a 100% complete comparison. Without you building the exact same bike, riding both, same track, etc. and what's the point of that? You may or may not see my point on comparisons, but that's what you are doing with our 2 different bikes.

 

 

Link to comment
Share on other sites

Slower, since we have talked a couple times about this. I believed in a 1st gear start. So I tried this on hillshooting. My experience is that it dosent really work optimal for my setup or possibly hillshooting in general. This is my findings.

 

At 10,000 rpm with stock primarys and 22" tires.

 

A 17-41 gearing with 1st -4th is

38.4 mph

52 mph

63 mph

75.6 mph

 

A 15-43 gearing with 2nd-5th is

44 mph

53 mph

63.6 mph

76 mph

 

As you can see to have the proper hill speed with both setups. Being 1-4 1st gear is extremely short. Then the next 2 shifts are very close. So its basically the same spread except on the first shift.

 

I have tried both, and even at 44 mph wheel speed out of 2nd it still seems a tad short but pulls through the gears good. Now with the 1st gear 38 mph wheel speed it felt like i had to shift 5' out from the launch.

 

Now if you bump the gearing up to match coming out of the hole..1-4

 

18-38 gearing with 1st - 4th is

44 mph

59.6 mph

72 mph

84.6 mph

 

Now with that tall of gearing to come out at the same speed look at the spread on all shifts now. And on the hill you will never pull that 84.6 mph 4th gear. Unless of course you have a 150 hp 85 tq motor. I can pull the 3rd gear at the 72 mph but its to short at the top.

 

Not to mention the falling off the pipe on a shift to soon or something.

 

Note: I have tried all these various combos and a few others on the hill. And these are my findings. Hope that can help somebody.

Link to comment
Share on other sites

The question still unanswered is why..

i read the lockup thread.

the only point i see to the comparison is that your the man when it comes to clutch tunning

 

I've answered why & I'm trying not to come off as a smart ass.

 

Because it's producing better 60's than the vast majority of bikes. Most of which are way lighter chassis/rider's, more power, better chassis & the list goes on.

 

Do I attribute all of our 60' to the 1st gear launch no, but it plays a big role. Along with the clutch, chassis angles, weight placement, launch rpm, transmission ratios & the list goes on.

 

Here's why we do it, because it works for us! To each their own, if you choose to do it our not. That's your choice.

Link to comment
Share on other sites

Possum,

 

This is where I'm going to start on this one & most will probably not like my answer.

 

You hill guys are all worried about mph only. While it plays a factor, the quickest quad to a set distance in a drag race. Wins regardless of the mph.

 

Four Stroke Wars uses timers on the hill. The quicker ET along with reaction time will win the race regardless of mph!

Link to comment
Share on other sites

My experience : With a first gear launch on my 421 serval I had to run higher gearing and more paddle. 10 paddle extreme with a +6 arm it hooked very well. Almost never bogged. you didn't have to worry about wheelies as much once you launched. With a second gear launch I had to gear the bike down and run less paddle 9 hauler or padla brat worked good. The bike would bog or spin the tires a bit then wheelie very quickly and some times wheelie in 3rd and 4th. I believe it 60 ft was better leaving in first but I don't because I never had it at a track.

Link to comment
Share on other sites

Im not worried about mph as much as being faster. Im using mph for reference to something common. It felt way faster and was faster. My e.t. was way better with 2-5 on my bike. Yes we were timing it.

 

I guess im way off here. I thought we were gonna have a conversation. Carry on.

Link to comment
Share on other sites

Im not worried about mph as much as being faster. Im using mph for reference to something common. It felt way faster and was faster. My e.t. was way better with 2-5 on my bike. Yes we were timing it.

 

I guess im way off here. I thought we were gonna have a conversation. Carry on.

 

Your not way off, we just see things differently on this subject. It doesn't make me/you right or wrong.

 

Your quote is confusing: Why use mph as a reference to something common or put into feelings it was way faster. All of that's pretty irrelevant if you were timing it. Timing is the best reference to something common IMO.

 

Nobody is twisting anyone's arm here. The 1st Gear Launch, All The Secrets! This is just a couple areas I'm sharing my thoughts/opinion(s) on this subject. I forgot, LOL! with all the secrets BS.

Link to comment
Share on other sites

Let me rephrase i guess i missed it..

What aspect of the 1st gear launch helps produce a better 60ft time than the vast majority of smaller lighter more powerfull others?

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...