karasaki 500cc Kart Project

[CustomShifter]

Man that sucks... but how thick should my frame be
like thickness of the wall.

 

[CustomShifter]

to be sturdy yet light?

 

[T.E.D. Jordan]

It depends what style frame you're going for and how much you want to spend CDS/Seamless tubing as per rollcages is a stronger tube/weight. For tarmac I'd aiming for around the 30mm / 11/4" if it was to be a similar design to normal tarmac karts.

Jordan

 

[CustomShifter]

Kart

It depends what style frame you're going for and how much you want to spend CDS/Seamless tubing as per rollcages is a stronger tube/weight. For tarmac I'd aiming for around the 30mm / 11/4" if it was to be a similar design to normal tarmac karts.

Jordan

Yes it will be a tarmac kart i want it to handle stress at high speeds btw i have a pic ill post later of my design

 

[CustomShifter]

BTW hows ur back?

 

[T.E.D. Jordan]

All better thanks for asking!

Should have an update later, recieved my extra bearing carrier but it might cause me some problems as I couldn't get another the same.

Jordan

 

[CustomShifter]

Np and i hope it fits

 

[flowerman]

This is such a sweet project. Make sure you keep us updated.. looking forward to seeing a vid of this soon.

 

[T.E.D. Jordan]

Thanks guys,

Had an awful day regardless of progress.

New extra carrier, couldn't find a match to the other two so I'll probably order two more the same. Fine for now anyway.

Assembled with new bearing (pointless pic but a pic none the less lol)

Lifted the engine about the top pivot, propped it up with jack stand lol. This allowed me to clean up the rail at the back as it had developed some surface rust.

I then marked off the centre of my engine bracket, then dropped the centreline to the frame rail which gave me my centre to position the brackets.

Assembled the tie-bars and tried the adjustment level. Not bad with about 15mm of tension available, should be reasonable. (read on though...)

Ignore the power craft box. Its just storing bike parts. I would never buy anything power craft!!!

In summary though.....my rear engine mount has taken a step backwards. The freedom of both rose joints means that the engine sways about 20mm side to side, which is what I was afraid it might do. I'm going to have to limit the sway somehow, but I might make something else altogether.

The only positive I have today on this is that I started getting used to this welder and had some reasonable welds.

I could do with suggestions as to what motorbike brake disc/calliper

It can't be over 230mm (Ideally it would be 230mm - as big as possible) has to be hydraulic and not have those square pads. Hate those!

Jordan

 

[anderkart]

In summary though.....my rear engine mount has taken a step backwards. The freedom of both rose joints means that the engine sways about 20mm side to side, which is what I was afraid it might do. I'm going to have to limit the sway somehow, but I might make something else altogether.

How about 2 more long turnbuckes attached through that top motor mount bolt, and angled all the way out to the side frame rails. I remember you were concerned about chain clearance, but it kinda looks like that side might clear when bolted to the engine up higher like that.

 

[T.E.D. Jordan]

I'm not sure that would work as the engine mounting isn't central about the frame and it would mean one bar would be longer than the other although I could equalise them with the bracketry I suppose. It would probably clear the chain on that side, but on the otherside thats where my exhaust has to be so I'm a bit snookered.

Before I bin this idea, I'm a complete noob anyway as theres just a rod in the front pivot at the minute that I forgot about, its not clamped together so as I need to buy a long bolt to go through there (200mm/8") I'll buy a graded one and torque it up. Its a tight fit as it is but with the weight and length of the engine it was moving. The front engine mount was over-engineered simply because of that reason and I just forgot lol!

I'll try and find one to order today so I can nip down and try it through the week

Jordan

 

[benjamin]

Evening Jordan,

Out of curiosity how are you mounting the exhaust/ radiator if the engine will move +/- 15mm with the chain tension? Adjustable mounting brackets?

 

[T.E.D. Jordan]

Hey ben,

The radiator will be mounted to the frame and the pipe will be silicone/rubber with enough distance to cope with that kind of change easily, and I have found a small st/st flexi-section for the exhaust that I planned on using.

Hows your kart coming?

Jordan

 

[EC1]

Quote:
Originally Posted by T.E.D. Jordan
In summary though.....my rear engine mount has taken a step backwards. The freedom of both rose joints means that the engine sways about 20mm side to side, which is what I was afraid it might do. I'm going to have to limit the sway somehow, but I might make something else altogether.


How about 2 more long turnbuckes attached through that top motor mount bolt, and angled all the way out to the side frame rails. I remember you were concerned about chain clearance, but it kinda looks like that side might clear when bolted to the engine up higher like that.

Man, you're the kind of person that if they can draw or think of something, they can build it.

Rather than adding turnbuckles, would relocating the existing to bearings on the axle instead of the kart frame possibly work? Achieving the greatest possible angle with one turnbuckle parallel to the chain, and the other theoretically intersecting as close as possible to the drive sprocket (along the z-axis, or rather looking down above the kart) would eliminate side movement and still let you adjust the chain.

Of course you would at least need to add a third bearing for this to work.

 

[EC1]

Another solution? Use an even longer mounting bolt at the front of the motor by an inch or so on each side. weld large wall thickness "bushings" on both sides of your motor mount for the longer bolt, and tighten really well to complete the rigidity. I then can't see where any side play could be introduced.

 

[T.E.D. Jordan]

Thanks for the compliment fella.

It took me a while but I think I know what you mean re. your first suggestion. I might do something like that, great suggestion.

Your second suggestion isn't a bad idea either although I'm going to wait and see what the engine is like when I've recieved the graded bolt through tomorrow and toqued it u, as the front engine mount is Massively over-engineered to allow me to tighten the long bolt through with around 35Nm or force. (The bolt is only M10 so thats quite alot).

Jordan

EDIT: Just noticed how awful fabrication work can look in pictures where its rusted over a little

 

[Rookie25]

This kart looks awesome. i have a 750cc honda sitting in the shop right now that i will be using on a kart. im getting some help with frame plans from a guy on here so that really helps and what i miss/forget, i can go back thru your thread and figure out what i need to do next. cant wait to see the next steps and the finished product.

 

[T.E.D. Jordan]

Thanks, although mine isn't the only good thread on here to use as I have myself

Get some pics up!

Got my bolt through today, actually got two as its good to have a spare incase for some incredibly random reason the torque procedure goes wrong. Although I'm working this weekend on the mornings again I'm hoping to get a bit done, possibly the start of a seat mounting which I'm hoping to triangulate to the frame to gain rigidity over that area.

Jordan

 

[CustomShifter]

Jordan honestly in my opinion this is one of the best forums on this site. Just saying.

 

[Rookie25]

This is my thread, i only have pictures of the motor i will be using, but once i get started on the frame and mounts there will be plenty more pictures going up.

http://www.diygokarts.com/vb/showthread.php?t=15638