Let's talk about Seat Position


(Liam Sergeant) #83

Hey Marin,

Thanks heaps for that!

I’m running Carrs Rd (Canterbury) and currently have a set of Vega (Open?) tyres on until they wear out and I’ll get the Dunlop’s. I definitely had issues getting the tyre pressures right the previous few sessions. Last time was pretty good and I felt a lot more confident.

I’m still 2 seconds off the pace so I know there’s lots and lots of improvement before I’m anywhere near the karts limits.


(Shawn O'Hara) #84

What cold pressure are you starting at with the vega’s? 9-10 is what I usually start mine at in the KZ.

Honestly the Canterbury track is bumpy as all hell and definitely the worst NZ track iv’e been on especially the section of turns that runs between track entry and track exit so i’d say expect to be loose through there

Come try Blenheim or Nelson. Much nicer…


(Liam Sergeant) #85

I’ve been struggling to go with the “correct” tyre pressures. I tried starting low and found I had no confidence/grip, then I put them up around 16 and they were better but also skittish.

Last time out I worked on getting the tyre pressure in the pits to down to 11psi after starting at 14psi. I found 12-13 to be grippy but my rear would get more over street towards the end of each session.

@Noahkoenig134
I have my front set to 15mm spacers inside hub (was previously 20mm) per side, and rear track to 1395mm. Is that what you mean by set up?


(Marin Vujcich) #86

Hey
15mm front ok.
1395mm too wide. 1380-1385mm. Your tyres getting worse in sessions suggests too high pressures. Unfortunately driving fast on cold tyres at correct pressure is an art in itself and took me a few years to be comfortable ragging to first couple of laps with a super loose kart.
Next time at track weigh your front and rear on weigh scales (if floor is level with scales) to get split weight. 58/38 is the starting point with these chassis.


(Noah Koenig) #87

Yes, that is what I mean. These measurements are standardish for the kart. I agree with Marin that your pressures are a little high at the moment. Driving with cold tires is a valuable skill that all the front runners have. It takes time to learn that though.


(Davin Roberts Sturdivant) #88

Seems like a little more seat time on cold tires might be more helpful too, just to get used to the kart in a wider envelope.


(Jonthan Stewart) #89

I really believe this is something that new drivers should be aware of. This is one of the biggest things I’ve been struggling with. At best I can be 0.5 seconds off the leaders, but the first few laps I am all over the place.

What do you mean here? 58 + 38 doesn’t add up to 100. My kart is 58% rear, which means 42% front.


(Dom Callan) #90

I.struggle with getting to Pace on cold tires too. I suspect experience will be the answer


(Marin Vujcich) #91

What do you mean here? 58 + 38 doesn’t add up to 100. My kart is 58% rear, which means 42% front.

Geez, and I’m a engineer. Scary aye.
Yes 58/42


(Andy Kutscher) #92

Gents, bumping this back up for a quick question.

Mounting a seat on my “new to me” Tony Kart 401. The seat placement guide for OTK is pretty good in my opinion.

If i went directly off the guide I’d place the seat at 625/630, and 5-10mm below the chassis rails. I even got an OTK seat to keep things simple and take as many variables out of the equation.

The question is in regards to a blurb in the OTK guide that says to move the seat back 10mm for “hard tires”

We run Bridgestone YLC’s which I believe is considered a pretty hard tire in the grand scheme of things. So should I go 635 /640 based on the hard tire?

I also almost got down to my target weight but not quite, I do fit in a size 3 seat vs. the 4 I thought I was going to have to be in. any additional considerations for being fat other than keep the seat low to minimize the effect of the weight on the kart?

Thanks,


(TJ Koyen) #93

The YLC would for sure be considered a hard tire in this case, so I would probably go for the 635 measurement, see how you feel in that, and adjust if you think you need to.


(Andy Kutscher) #94

Follow up to my follow up.

Had the first outing in my kart yesterday doing some pre-season testing. Set the seat at 635/640. Track was green and on older YLC tires. A couple of the top guys from our class were there as a bench mark and I had good pace.

In reflecting after the fact I had an advantage of rear grip over others yesterday which was giving me an advantage in several spots. But in big sweepers I felt like the kart wasn’t releasing quite as well as those others. I’m guessing as temps start to raise and the track starts to get rubber in it that my advantage is quickly going to turn into a disadvantage.

I went 10mm further back based on the “hard tire” suggestion in the OTK guide, but in looking back I’m still ignoring that I’m 210lbs with gear on and moving that much weight back in the chassis is more than likely going to cause me issues down the road with releasing off the corners.

Would you guys agree…I’m going to position the seat for 625/630 this week so that I’ve got the ability to move it back and forth but I’m pretty sure that the 625 is where I need to be even if I lose another 10-15 lbs. I was 12 over min weight yesterday so I’m MUCH closer than I was last year.


(Dan Dedering) #95

Do you know what your front to rear weights were at that seat setting?


(stamatis stampelos) #96

You need to weight you with the kart, and see how far have you been from the baseline set up first.


(Andy Kutscher) #97

I guess my big weight isn’t throwing off the balance as much as I may have anticipated.

Kart is 42/58 with the seat at 635/640. Given that I intentionally moved it back 10mm from standard for the hard tire recommendation from the setup guide I think I’m going to make holes to move it back 10mm forward but likely leave it where it sits at least for the beginning of the season when it’s cold out and we’re going to be struggling for grip at our local club track.

When I moved myself forward slightly in the seat It moved to around 44/56 so I know that 1) I’m not far off should I decide to move it and 2) it doesn’t need to go very far to get there.


(Daniel Wilkinson) #98

Hi all, new to the forum and karting in general, slowly getting my first kart setup ready for its first use, my problem is I’m only 5ft 3 I have an older Tony kart venox chassis and have set the seat in accordance with otk chart right at the front, Ive installed a heel rest as well (without it my calf’s would be on the tie rods ( any small turn they actually still are on the tie rods).
My question is should I raise the seat to stop my legs sitting on the tie rods? Some I’ve seen have put in heel risers, (but I’d still struggle with the pedals thinking about it) so would it be possible to fit a pedal extension kit? Noticed the fitment of some extension kits are for the newer chassis so don’t know if they would fit mine. As the ones I’ve found all fit the same.

Ignore the seat in this photo, I have got one a lot smaller than this one and I think there is about 10mm between the column uprights and the seat haha


(Liam Sergeant) #99

When I was reading up on where to put my seat there seemed to be a general consensus that shorter (and potentially lighter) drivers should/could raise their seats for better leverage.
Where is your seat bottom in relation to your chassis rails currently?


(Daniel Wilkinson) #100

I’ve just gone off the otk fitting guide so the flat of the seat is flush with the top of the chassis 40mm up from the guidline of 10mm lower than the chassis as the norm.
Hope that makes sense. I’m going to have to change something as my arms are only just bent when reaching for the steering wheel and the column is on its lowest setting too.


(Daniel Wilkinson) #101

How high would be recommended? I understand it would be different for all drivers bit of pain being short sometimes.


(Daniel Wilkinson) #102

Well I’ve just found some info, this seat position stuff is nuts, an Otk chassis setup guide is what I went off for putting my seat in, loads of info on setup not just for the seat anyway, this is the one I’ve used. Set at 605/610/ 240.

This is also an Otk fitting guide any ideas which one is the correct one?

Bit confused since both are the same wheelbase and Otk left me scratching my head this one.