[Kartbuilding] go kart steering question

[Stephen Burke]

Hi Rick,

I'm glad you got the kart sorted. Thanks for letting me know too. Perhaps 
this adjusting of the front spindles will help someone encountering these 
problems in future!

You were lucky there were adjusters built into the spindles (king pin) to 
allow for adjusting the height. It is strange how it made such a 
difference. I've had a similar issue with a chassis, and I managed to 
successfully adjust it with some brute force. It did work. In my case, I 
drilled a mounting hole in the chassis (BAD idea. I now weld a lug onto 
the chassis onto which to bolt items), and it gradually bent in this 
location. After realising this, I managed to bend the chassis back (by 
putting one of the front wheels and one of the rear wheels on blocks, 
supporting one corner and pressing down on the opposite corner. It worked 
quite well. When I had the chassis straightened, I welded a extra bracing 
piece to it.

Anyways, glad you got your kart sorted.

Best of luck,
-steve

On Sun, 3 May 2009, Rick Burger wrote:

>
> Steve,
>
> Here is an update;
>
>
>
> Since the seat and engine are centered I knew the left pull could not be a balance issue. I set the rear axle on jackstands and a single stand under the front. The distances between front spindles and rear axles were the same so I measured the height of the front spindles.The left spindle measured 3/8" higher from the floor than the right. The cart has height adjusters for the front so I adjusted them to as close as the adjustment would allow and what do you know, it tracks almost straight. So I can assume that the frame is twisted slightly. I wouldn't have thought that little bit would make such a big difference.
>
>
>
> Thanks for your help on the other issues!
>
>
>
> Rick Burger
>
>> Date: Tue, 28 Apr 2009 19:53:45 +0100
>> From: sburke
>> Subject: RE: go kart steering question
>>
>> Hi Rick,
>>
>> I didn't realise that the kart also pulled towards the left.
>> Yes, if you bounce the front of the kart, the front wheel should point
>> forwards.
>>
>> Have you repositioned the seat in the middle of the chassis?
>> It could be the weight distribution pulling the kart to the left.
>> You could sit someone in the kart, and lift the front end. Does one side
>> feel heavier that the other?
>> Try lifting the rear of the kart. Does one side feel heavier?
>> This could indicate that the weight is not centrally balanced.
>>
>> You could also check to see that with the wheels pointing forwards, that
>> the distance from the front left to the rear left axles are the same as
>> the distance from the front right to the rear right axles.
>>
>> You may need to check the camber angle of the front stub axles.
>> See: http://blog.kartbuilding.net/category/steering-setups/
>>
>> Best of luck,
>> -steve
>>
>>
>> On Mon, 27 Apr 2009, Rick Burger wrote:
>>>
>>> Steve,
>>>
>>> Thank you for your quick response and sharing your knowledge. Everything you mentioned makes sense. The engine is now positioned slightly behind the rear axle, thus making for a light front end. I am considering relocating the axle farther back or adding weight on the front. The rear wheels are 6 inch wide which came on the cart but I put on 15 inch tall turf tires, with 13 inch on the front. I have not tried the cart in the dirt yet, I have just been running it up and down the street, trying different things. The only thing that still is confusing is why it pulls left. Were these race carts built to pull left or could I have a bent frame? If I center the wheels then bounce the front end a few times, the wheels will center themselves pointing left about 5 or 10 degrees. What do you think ?
>>>
>>> Thanks again!
>>> Rick Burger
>>>
>>>> Date: Mon, 27 Apr 2009 20:17:22 +0100
>>>> From: sburke
>>>> Subject: Re: go kart steering question
>>>>
>>>> Hi Rick,
>>>>
>>>> The reason the steering is difficult is due to the live rear axle, to
>>>> which both rear wheels are attached.
>>>> In cars, smooth cornering is acheived by using a differential. See:
>>>> http://www.kartbuilding.net/drive/Differential.htm
>>>>
>>>> On the kart you have, the reason for the problem in steering is due to:
>>>> Insufficient weight on the front wheels (as the engine is now further
>>>> towards the rear axle)
>>>> Were the new rear wheels you added wider?
>>>>
>>>> On a typical kart with a solid live rear axle, when cornering, the inside
>>>> rear wheel MUST slip (read the above page). (imagine a runner on an oval
>>>> track. The distance on the inside is less.).
>>>> If you have more weight on the rear axle (as opposed to centrally based on
>>>> the kart) it will allow the front wheels to skip and hop.
>>>>
>>>> It all depends on how bad the skipping and hopping of the front wheels
>>>> are. Typically on a racing track the kart is going quite fast, allowing
>>>> the rear axle to slip and slide (a little). At slow speeds it will be
>>>> difficult no matter what kart it is, with no differential. It would also
>>>> be fine on grass or gravel, as the inside rear wheel can spin more easily.
>>>>
>>>> If you are on tarmac/concrete pavement then it will be very difficult to
>>>> achieve smooth cornering.
>>>> One possible solution is to change one rear wheel. Attach one of the rear
>>>> wheels to the rear axle using bearings. Essentially the kart will be one
>>>> wheel driven in this case. This will make for excellent cornering, but in
>>>> an off-road situation this would not be ideal.
>>>>
>>>> How was the cornering ability of the kart before you made your changes? I
>>>> think its cornering might not have been much better at slow speeds.
>>>>
>>>> I hope this information helps.
>>>>
>>>> Best of luck,
>>>> -steve
>>>>
>>>> On Sun, 26 Apr 2009, Rick Burger wrote:
>>>>
>>>>> Steven,
>>>>>
>>>>> I just found your blog and would like to pick your brain if I could. I purchased a used go kart frame that was used for racing originally. I moved the engine from beside the seat to behind and put taller tires on. I have tried to adjust the toe to about 1/8" toe in. The cart pulls left pretty hard no matter what I do with the toe setting or centering the steering wheel. Also, when turning on pavement at slow speed, the front tires try to hop and skip. Any suggestions as to why these are happening and what I can try to fix it?
>>>>>
>>>>>
>>>>> Thanks!
>>>>>
>>>>> Rick Burger
>>>>> _________________________________________________________________