First kart project

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karte_m0lim

karte_m0lim

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looking good ..

I know that you are impatient, but maybe you should assembly it first, and after everything fits in place, disassemble and do the paint.

Just in case you have to change something, add some weld or something .
 
fast92rs

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I'm not sure. It will be pretty tight. I built it for my son to use. I didn't stretch it from the plans. The only way I could probably fit in it is if I remove the steering wheel, sit down then place the wheel back on.
 
fast92rs

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Ok took out for a ride. I was barely able to fit into it but I did. Just couldn't get my feet on the pedals. Lol.

1) The one problem I noticed is the sprocket is really close to the ground. On even pavement not a problem but any bumps such as going up the driveway from the street or sidewalk it scrapes. I have 11" tall rear tires so I guess going with 12" tall tires could improve clearance.
2) The second problem I have is the steering. I knew it would have some issues. I did change the caster to 5 degrees before painting it and set the toe to zero. The problem is the turning at hard right and left turns. The turning radius does suck because of the lack of Ackerman. Besides messing with the spindles I was wondering if I changed the relationship between the width of the front and rear tires to be as close to even as possible would that help steering? I mean if I were to push the rear tires in and the front tires out slightly so that the outside edge of the tires almost matched from front to back would that change the way it steers as well?
 
OzFab

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fast92rs said:
1) The one problem I noticed is the sprocket is really close to the ground. On even pavement not a problem but any bumps such as going up the driveway from the street or sidewalk it scrapes. I have 11" tall rear tires so I guess going with 12" tall tires could improve clearance.
Click to expand...

The alternative is a smaller sprocket, which will, technically, have the same effects, higher top speed but less torque...

fast92rs said:
2) The second problem I have is the steering. I knew it would have some issues. I did change the caster to 5 degrees before painting it and set the toe to zero.
Click to expand...

Toe should not be set to zero, they should toe in a few degrees

fast92rs said:
The problem is the turning at hard right and left turns. The turning radius does suck because of the lack of Ackerman.
Click to expand...

That's a surprisingly easy fix; have a look at this thread

fast92rs said:
Besides messing with the spindles I was wondering if I changed the relationship between the width of the front and rear tires to be as close to even as possible would that help steering? I mean if I were to push the rear tires in and the front tires out slightly so that the outside edge of the tires almost matched from front to back would that change the way it steers as well?
Click to expand...

That could work...

Yet another alternative is to have one coaster wheel on the axle as opposed to two locked wheels; simply replace one keyed hub with a bearing hub...
 
fast92rs

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Thank you for the reply. I will reset the toe in and look into the bearing hub. Does anyone sell a Pittman arm plate like the one in that thread or is it fab yourself only?
 
M

mckutzy

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An Idea I see as mentioned about low clearance with the sprocket, the brake lever.
If it were me Id change the lever to actuate the caliper from the top as the Low clearance might cause issues at some point, and have a potential damage to the brakes. Based on the pics you look like you have room for the rod.

Looks cool and pretty sturdy.
 
H

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fast92rs said:
1) The one problem I noticed is the sprocket is really close to the ground. On even pavement not a problem but any bumps such as going up the driveway from the street or sidewalk it scrapes. I have 11" tall rear tires so I guess going with 12" tall tires could improve clearance.
Click to expand...

Thats one way of doin it... or you could change the gearing to a smaller config at the axle(maybe).

fast92rs said:
2) The second problem I have is the steering. I knew it would have some issues. I did change the caster to 5 degrees before painting it and set the toe to zero. The problem is the turning at hard right and left turns. The turning radius does suck because of the lack of Ackerman.
Click to expand...

I myself would have done a 10-12 degree caster... I have 14 on my karts and they turn on a dime... almost quite literally. Also along w/ your lack of Ackermann... it appears the arm off the steering shaft (where the tierods connect), is alil too short, which is another issue that is limiting your turning radius. However, you have enough of an arm to make/attach the noweld plate, link that Fab sent to correct the Ackermann... and the plate should compensate for the length needed to tighten the turning radius even further/more precise.

fast92rs said:
Besides messing with the spindles I was wondering if I changed the relationship between the width of the front and rear tires to be as close to even as possible would that help steering? I mean if I were to push the rear tires in and the front tires out slightly so that the outside edge of the tires almost matched from front to back would that change the way it steers as well?
Click to expand...

... the narrower the rear, in relation to the front, the easier/responsive the turns made... the wider the rear, the harder(but more caster helps LOTS).
... the narrower the front, in relation to the rear, the harder/less responsive the turns made... the wider the front, the easier(NOT sure if less caster helps).
 
fast92rs

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Ok thanks. Tomorrow I will space the front out a little more and move the rear tires in more and see how it reacts. I will read that thread again and see what I can do.
 
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