Karting1.co.uk

[Aussie Bruce]

Hey Jacksi

I don't really think you're going to get much better than what you're using at the moment if you're looking for acceleration. I'll give you some examples that I've worked out so you can compare :

current set-up : 11F + 86R at 13,900 = top speed 92.81 kmh
This must give you fairly good acceleration as it is as it does sacrifice a little top speed.

Example set-up 1 : 12F +86R at 13,900 = top speed 101.24 kmh
This means that your top speed has increased but at a small price because your acceleration will not be quite as effective.

Example set-up 2 : 11F + 84R at 13,900 = top speed 95.02kmh
As you can see, top speed has increased slightly and so your acceleration will not be so nippy. Hardly noticible but ..... !

Example set-up 3 : 11F + 88R at 13,900 = top speed 90.7 kmh. This will increase your acceleration a little but drop your top speed down by about 2kmh.

Always, the biggest problem is how you drive the kart. Some guys can be magic with a smaller sprocket and get ot the podium in front of other guys with better acceration because they've got a larger rear gear - it's just the way they drive the kart ......

if you can carry 2 kmh more into the corner (maybe brake more lightly), but maintain 100% traction by braking in a straight line, then trail-brake by overlapping the start of cornering phase (turn-in) with braking but still maintaining 100% traction overall, steady acceration through the middle phase of cornering so the traction is loaded on the cornering, then overlap the cornering traction with some acceration as you approach the exit (ie diminish the traction used for cornering by starting to unwind the steering and replace that with traction used for acceration which still maintains 100% tractiono overall), then you could even drive with a Massey Ferguson tractor gear of 932 teeth and still get out onto the straight before anyone else.

Easy to say huh ? You bet ...... and it takes loads and loads of practice and when it works it's magic. But you gotta push yourself just that little bit harder. I mean, whats gonna be the blow-out point ? A littel spin somewhere ? Oh well, life goes around in circles at the best of times ......

I hope that helps a bit.

Now here's a question for you guys .............

I know that Rotax doesn't have any flexible pipe in the exhaust so they're out of it before we start, but for Easykart and Leopard drivers and all those other karts that carry some flex pipe before the pot :

What gives better acceration : a slightly longer piece of flex or slightly shorter ?

I've been told slightly shorter gives better accelertion and if you're on a course which has some good straights, then a longer flex would be an advantage.

Let's here from you on this one

Cheers

bruce
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C'mon Aussie, c'mon

[Nick]

[Aussie Bruce]

Hi Jasper,

I was a bit of a bridesmaid in the results department unfortunately - in 4 races I only got 1 2nd, 2 3rds, and a 5th.

They put all the Rotax's in with the X-30's which made it difficult because they're FAST. And ..... 60 racing laps between 8am and 2pm is hard work even for a young fella like me.

I was best out of all the Rotax's though which was pleaasing because this was the first time I have actually raced the thing and I've only actually driven a Rotax two or three times before. I do know the chassis though 'cos it's my old Sodi SR3 so I guess that helped a bit.

Biggest problem now is I have to buy Suzie some more tyres 'cos I've sort of worn hers a bit.

I'm not overly impressed with the Vega Greens either - seemed to be very slippery to me and lost traction quite early after turn-in so I changed the chassis set-up to compensate but as the day went on they went from bad to worse until in the end I was driving using hardly any brakes and using the loud pedal for steering.

I'll check that other website you mentioned when I get back from work - gotta go and earn some money so I can pay for Suzie's new tyres (NOT
Vegas - Bridgestone this time I think).

Ciao

bruce
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C'mon Aussie, c'mon

[jacksi]

hey aussie and thanks for the tips i like it
can you tell me the following 11-85
12-85 12-87 12-88 thanks and how do you work it out ?
if i measure the exact track and stuff how does it work?
does the chain lenght make a difference?
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jacksi racing
malta

[Aussie Bruce]

Hi jacksi

No worries - all calcs based on 13,900 rpm

11/85 = 93.9 kmh
12/85 = 102.43 kmh
12.87 = 100.08 kmh
12.88 = 98.94 kmh

The calculations are a little difficult but there is a very easy way -
Jasper just posted a website reference to me and I checked it out - it's not bad - in fact, it's bloody good in that it provides a lot of very helpful imformation especially the kart set-up tech calcs. Thanks Jasper.

It is a fantastic site for the Poms 'cos they can see at a glance some of the best setups for their karts at a lot of tracks throughout the U.K.

You may be able to do some comparisons with those tracks to that of yours over there on that little sunny island of yours - you'll have to research the U.K. tracks on their websites -

here's the link : http://www.sykc.fsnet.co.uk/gearcalc.htm

I'm sorry, you'll have t type it all out because the hyperlink gizmo doesn't seem to wanna work when I type it in - maybe it'll do its thing after I post this, who knows - computers are just as confusing to me as the way the dork in front of me was driving on Sunday morning ...... !

The length of chain you need depends solely on the amount of room you have to move the motor backwards and forwards while still leaving about 1 cm of play top and bottom. Of course, if you want to move the whole thing right under your right foot and shorten the accelerator cable quite somewhat, you're going to need a chain big enough to drive a front-end loader .........

Don't forget to check the chain adjustment all the way around as there is always a tight spot because the pinion never turns exactly evenly (don't ask !!) Adjust the chain to the tightest spot on the rotation.

Also, some karts, though not all, and some more than others, have a tendancy to tighten the chain when the front engine support bolt is tightened and slacken it when the rear engine support bolt is tightened - VERY FRUSTRATING - especially if you're in a hurry to get to the pre-grid.

Hope that helps

Cheers

Bruce
_________________
C'mon Aussie, c'mon

[jacksi]

hey aussie thanks allot i have been on the site it is great.
so if i put the axle sprocket size and the tyre circ. then the rpm it shows the data underneath but witch is it there are allot of boxes but there isnt a box where you put in the engine sprocket size.
com on aussie com on we are allmost there the last step please
i am going to go and get the exact lenght of the track this morning if i can i will try to draw the track out aswell if i find find how to put it on the computer i hate computers
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jacksi racing
malta

[Nick]

[Nick]

[Nick]

[jacksi]

thanks jasper i finally got it
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jacksi racing
malta

[Nick]