Chassis issue.

[Poboy kartman]

When was the last time you saw a racing kart with an engine mount welded to it?

These frames are made in such a way that they're designed to flex through the length of the chassis; if the two engine rails are bound together by welding, the amount of flex is reduced.

The fact that it's only the left wheel is lifting so high means that the right side of the frame is not flexing as it should... & where is the engine mount?

Also, if the chassis wasn't sitting dead flat when the engine mount was welded on, it will have a twist built in, not to mention distortion caused by welding...

I have to agree- seeing way too many things to make me think this was homebuilt and not a production racer....however take that with a grain of salt....as if you you take what I know about race karts and a HANDFULL of salt. ...and your fries will be bland......

BTW- I'm curious where the OP is from....he may be a fellow countryman. ....yours- not mine....Lol.....

But it looks to me like the former owner was a butcher by trade....and liked playing with metal after hours. .....I second the request for more total frame 3d pics......

 

[OzFab]

seeing way too many things to make me think this was homebuilt and not a production racer....

Are we looking at the same kart? IMO, if that frame is home made, it's really well done...

 

[Poboy kartman]

Are we looking at the same kart? IMO, if that frame is home made, it's really well done...

Please reread my post.....you are contradicting what I said... we are in agreement. ......

 

[firemanjim]

When was the last time you saw a racing kart with an engine mount welded to it?

These frames are made in such a way that they're designed to flex through the length of the chassis; if the two engine rails are bound together by welding, the amount of flex is reduced.

The fact that it's only the left wheel is lifting so high means that the right side of the frame is not flexing as it should... & where is the engine mount?

Also, if the chassis wasn't sitting dead flat when the engine mount was welded on, it will have a twist built in, not to mention distortion caused by welding...

For some reason I can't see ANY of the pics but I have to totally agree with Tony on this. These karts ARE meant to flex. That is the purpose of the clamp on mounts. They allow the chassis to flex, while still hold the engine in a rigid location. In a turn, at speed, the flex action helps to keep the tires planted to the ground. Without it, and you get what the OP has, a wheel in the air.... And did you catch his valuable tid bit key of info that he used to come to his conclusion? The location the engine mount was welded to.
OP, do your self a favor and get out the cutting torch.... NOT REALLY! Carefully cut the bars off with a cutting disc on a diet grinder or a saw or something. Repair the PO's dumbassity, and get the correct clamp on mounts. Or if you have to, buy a set of clamp on's and modify it so your engine bolts to it, but still clamps onto the chassis as intended.....

 

[Poboy kartman]

I have to agree- seeing way too many things to make me think this was homebuilt and not a production racer....however take that with a grain of salt....as if you you take what I know about race karts and a HANDFULL of salt. ...and your fries will be bland......

BTW- I'm curious where the OP is from....he may be a fellow countryman. ....yours- not mine....Lol.....

But it looks to me like the former owner was a butcher by trade....and liked playing with metal after hours. .....I second the request for more total frame 3d pics......

Since Tony misread my post and I can see how it could be mistaken by the way it was worded....I will change it slightly. .....I am seeing way too many things on this kart that contradict it being a homebuilt kart and look professionally done and racekart worthy that I have to agree with Tony- however- my knowledge of race karts is limited- but from what little I know- that's what it appears like to me- a production race kart.....so taking my limited knowledge into account- take that opinion with a grain of salt.....
Thanks- sorry for the poor wording in the earlier post- but that was what I intended to say.

 

[Ashlar]

Sorry guys i live in england so have been asleep pictures from all angles to follow.

 

[Doc Sprocket]

I think I'd be stripping the frame down, leaving only the spindles on, setting it a known level and true surface, and taking a series of measurements looking for symmetry. The last time I came across exactly this, it was in fact a twisted frame.

EDIT- In fact, here is a pic of me using a very expensive precision frame straightening machine...

 

[Ashlar]

right these are the pics I have just took .. in the confined space of the garage.

http://i1182.photobucket.com/albums/x446/Ash_Daniell/IMG_0052.jpg
http://i1182.photobucket.com/albums/x446/Ash_Daniell/IMG_0047.jpg
http://i1182.photobucket.com/albums/x446/Ash_Daniell/IMG_0045.jpg

engine seems far to over to the right on this picture.. yes theres a hole to move it back across so in theory the front wouldn't end up in the air but it then means chain rubs against the seat stay bars.

http://i1182.photobucket.com/albums/x446/Ash_Daniell/IMG_0041.jpg
http://i1182.photobucket.com/albums/x446/Ash_Daniell/IMG_0037-1.jpg
http://i1182.photobucket.com/albums/x446/Ash_Daniell/IMG_0001.png
http://i1182.photobucket.com/albums/x446/Ash_Daniell/IMG_0002.png

 

[Ashlar]

To me engine looks to far across rather being more inwards which would lessen the lift. I may add that engine flcannot be moved across due to vlutch and sprocket eating into the seat!!

 

[anderkart]

Hi guys i am new here. I have a kart and i THINK the chassis may be bent .

When i turn the steering right when no weight is in the cart the left front wheel raises fairly high of the floor i can get my hand flat under it. I turn to the right the left comes up but not as far. When weight is applied to the cart i.e me sitting in it what happens is if i turn right the front left bumper bar pitches up turn left the right bumper bar pitches up The wheels stay on contact to the ground tho. Now i hAve a gx340 lump on the back previous owner has just welded 2 lengths of box section to the frame and then bolted engine to them is this correct .... In my little technical knowledge would this exegerate the pitching of front end when turning left ?? From what i have just said could anyone guage were it could be bent so i can attempt to straighten it up .


Cheers lads / lasses

Ok, but the most important thing is: Does the kart seem to have any steering problems when your riding it?

 

[firemanjim]

I think I'd be stripping the frame down, leaving only the spindles on, setting it a known level and true surface, and taking a series of measurements looking for symmetry. The last time I came across exactly this, it was in fact a twisted frame.

EDIT- In fact, here is a pic of me using a very expensive precision frame straightening machine...

Mine is very much the same, I see.... Except I think your model is a little more precise.....

 

[OzFab]

Just as I suspected, the engine mounts are welded across the two rails; between that & the massive weight of the engine, I'd say that's most of your problem.

Follow Doc Sprocket's advice; strip it down, cut the mount bars off & go from there...

 

[Joe-405]

Is the axle mounted straight ? It looks crooked in the pics. Which might mean somebody did it on accident or used that as a dirt kart like mine was.

Mine is a mini sprint car. But i straightened the axle with different mounting points and fixed it. Cause mine did the exact same thing as you are describing.

 

[Dirtkarter]

Maybe I missed something as I haven't read this lot too carefully but..
Process of elimination, try taking the wheels and undertray off and anything else protruding below the bottom of the frame, find a surface that is flat and sit the frame down, if there are any gaps between the floor and frame then it is bent. While it is on said flat surface measure the C knuckles (or whatever they are called) front back left right etc aswell as from the ground to confirm they have the same inclination and layback. If your frame is twisted it is an easy fix, put a block of wood or something under one wheel and diagonally across hook the other wheel under a car bumper or something, then put some pressure or maybe body weight on the wheel that is up in the air to twist the frame in the opposite direction. Kind of hard to explain but if it comes to it I can make you a picture to illustrate. I definitely agree with Fabroman, these frames don't come out with problems. If anything was welded to the frame either the heat could have distorted it or it wasn't on level ground when it was done. Maybe one of your stub axles are bent? Hope this helps

Ok I didn't see this post before I commented, but the same advice.

I think I'd be stripping the frame down, leaving only the spindles on, setting it a known level and true surface, and taking a series of measurements looking for symmetry. The last time I came across exactly this, it was in fact a twisted frame.

EDIT- In fact, here is a pic of me using a very expensive precision frame straightening machine...

 

[Ashlar]

So many differant opinions. I spoke to a local kart circuit manager / engineer and he said that the front left is suppose to raise and left aint other wise it would not go round a corner he says its more a camber issue ... Just dunno which way to go with repairing this as i have limited resources

 

[J_Walker]

don't repair it. give it to me. ill pay for shipping...

no seriously. figure out the problem, don't try to guess it. get a level.. a level surface, and go from there. a ruler might help too. to figure out if its a bent frame, or a camber issue. basic tools to figure out the problem first. then move onto fixing the problem.

 

[anderkart]

... Just dunno which way to go with repairing this as i have limited resources

Have you rode the kart yet? If not you should, that's the only way to find out if it truly has any steering issues or not. My Beisse racekart had the same symptoms as you posted, but it handled awesome/turned right and left at high speeds equally well...

 

[Ashlar]

I have measured the kart fron ground to certain points and it all matches up ... I think its a culmination of camber / castor issues and that dam great lumpy thing on the back and bars being welded across. I did some more digging and from what i can understand a engine mount bolts to the engine then there are 2 clamps which clamp the engine and mount to the tubular chassis.... Surely then this would have the same affect as what i currently have going on.....