karasaki 500cc Kart Project

[T.E.D. Jordan]

Thanks for the interest guys, the karts still up on my bench I'm just awaiting a seat so I can crack on with it!

I want to get it finished so rest assured you'll see some progress soon!

Jordan

 

[T.E.D. Jordan]

Bought a seat amazingly it only weighs 1.5KG!!, not that I'm paying much attention to weight as it is, because theres that little to go on the kart its never going to weigh a massive amount! I'm stuck doing college work at the minute otherwise I'd be out working on the kart, should be able to get some work done maybe tomorrow afternoon, if not friday.

Jordan

 

[anderkart]

Nice seat Jordan. If you've never mounted one before it easiest to wedge some plywood between the ground and bottom of the karts frame so you can sit in the seat and choose its location. Most guys mount the seat with its bottom flush to the bottom of the frame for the lowest center of gravity, so the plywood also serves as a good guide here.

I'd try to get it mounted as far forward as comfortably possible to transfer all the weight you can to your front tires. (you'll need this for good steering grip with that engine back there...)

You'll find adjusting, modding or relocating your pedals to use up all the available space before hitting the inside of your front bumper will give you more leg-room if needed.

I'd wait to mount your seat until your kart was completely finished. You could then place a couple bathroom scales under each rear tire, (and while sitting in the seat), slide R/L a bit as needed to help balance your karts left/right weight bias to be as even as possible. Then mount it there. Its not uncommon for race kart seats to be offset to the side and it'll help your handling be more predictable. When you have it on the scales, It'd be best to block the front tires up to an equal height too.

 

[T.E.D. Jordan]

Thanks for echoing my thoughts, I've mounted two 'Tillet' seats in karts I've built before, and I've re-mounted countless others in karts I or my brother have had, and the method I've used is similar to the one you've described.

I've waited for a while to get this seat so I can decide on a final mounting position for the engine, even with the frame extension i'll end up fairly forward just because I need some clearance for the exhaust I want to make!

That last post did raise the comment re. the left to right bias. Its going to be dead central, as I've calculated my CofG for my engine and it will be hung so the CofG moment is centroid to the centre axis.


Jordan

 

[anderkart]

Yeah Not sure what happened there but I deleted the last 2.

I shouldn't offer unsolicited advice to guys that know more than me, and I got a feeling I did that here

 

[T.E.D. Jordan]

Yeah Not sure what happened there but I deleted the last 2.

I shouldn't offer unsolicited advice to guys that know more than me, and I got a feeling I did that here

Not at all, you'll more than likely know more than me about karts, but I'm a design engineer by trade who went through the system starting as a fitter then machinist, so I use that background in the decisions I make. So far you've confirmed what I've assumed or known from past experience but its good to know I'm heading the right way. don't stop with the helpful comments fella

Jordan

 

[anderkart]

Cool thanks,
Your doing such an awesome job and this build Its difficult to suggest anything that needs improving.

 

[T.E.D. Jordan]

Took the kart off the benches today and spent an hour or so cutting/grinding/flapping some of the miscellaneous mounting points etc that I no longer required, or that would interfere with new metal. Theres more to get rid of but I wanted to do a couple in particular as they sit right where I want a front seat mount/chassis brace.

After a while of measuring and careful placement, I mounted the engine bar in the frame too. Unfortunatly a combination of limited access around the joints and a slight breeze has left my welds unsightly, so I won't be posting pictures of those up. There're more than strong enough, just not pretty

Couple of pics - note engine isn't final positioned yet:

Maybe some more tomorrow as I'd like to get the front engine brace positioned along with the engine and welded in place to see what I can fabricate for the rear engine adjuster/mount.

Jordan

 

[anderkart]

Looking good man.

 

[T.E.D. Jordan]

Spent a good while centring the engines Centre of gravity about the frame centre. Got it as close I could, the weight of the ancillaries will be placed to balance it as best possible.

Welded all round

Also made the bar that will replace the green cross-bar shown in this pic. It's just sitting there at the minute as I want the engine back in to double check the placement and I didnt get time, but it should sit right on one of my extension joints which is great. That bar needs to be where it is to hold the rear engine mounts and it also has to be clear of the chain which the green bar is going to foul (meaning its going).

Jordan

 

[88s10Durango]

Awesom !! Your doing such a great job on this build , keep pluging away at it lol .

 

[T.E.D. Jordan]

Thanks

another update, although not a great one!

Bought an 8 ball shift knob off ebay for no other reason than I was ordering some special oil from a seller and saw they sold these so it rounded my total off nicely

Welded all my joints today too as there was no reason not any more, also welded my rear engine mount bar in. This will hold two uprights that will correspond in position to the rear engine bracket, and between both brackets will be the adjusters to let the engine lift and drop about the front (fixed) engine mount via two threaded bars.

apologies for this pic quality, shame as it was quite a nice weld!

Next step is designing the rear brackets and adjuster bar in CAD then getting them machined at Total Engineering Developments

Jordan

 

[anderkart]

That's a truly ingenious chain adjuster idea I've never seen on a kart before. Nice job man

Are the adjusters going to be angled outwards at the bottom so they can help limit sway?
I'm thinking maybe they should be attached way out near the main frame rails for this reason...

 

[T.E.D. Jordan]

That's a truly ingenious chain adjuster idea I've never seen on a kart before. Nice job man

Are the adjusters going to be angled outwards at the bottom so they can help limit sway?
I'm thinking maybe they should be attached way out near the main frame rails for this reason...

Thanks fella

You are correct, They'll be angled outwards as much as I can, like you say, to help limit sway. I've made the front engine mount as tight as possible (You almost have to hammer the engine in) and its incredibly rigid, but like you've spotted, it would still allow a bit of sway at the back so they'll be kicked out as far as they can (evenly) go, as the chain side will end up very close If I go too far. I may put the rose joints on the inside at the top just to allow for this, but I'll see next time I'm down my shed (tonight hopefully).

Jordan

 

[anderkart]

Cool, your welcome. I figured you were gonna angle them, but how about this Idea:

I see the frames cross member you've added, how about installing a 3rd, short/center/vertical adjuster, just to help brace things up even more?

With just the 2 outers, I was thinking maybe it could still end up with some lifting/torsional forces transmitted through the engines block. But with all 3 working together, it would be all braced up solid as a rock, pretty much just like a solid mount...

 

[T.E.D. Jordan]

I'm sure it'll be hellish stiff with what I've got, but If not its something I could definitely do. The main reason I haven't done this is because I've only got two hands to raise/lower the bars simultaneously and because the engine really does not move left/right with that front mount and how tight it is it It should de decent. Like I say though, I won't rule it out!

Mis-alignment spacers. I'm having Total Engineering Developments make these just because I don't want to use the thin ones with lots of washers and my usual stockist doest make them deep enough for what I want.

Martin will get round to them soon enough hopefully!

Jordan

 

[Bluethunder3320]

woah! youre putting some great time and effort into this! nice work! i cant wait to see what it turns into!

 

[anderkart]

10-four to that Ted.

 

[T.E.D. Jordan]

Small update (as per )

Dug my bearings out for the rear axle. Still need to get a rear axle...... but I have the bearings!

Well I have one of them, as 2 out of the three bearings are 'jeffed'. One of the ones I've condemned for the scrap bin isn't bad just a little bit more friction on it than I'd like.

Here are the housings, two outers and the inner carrier. A little bruised but every working face is perfect:

By chance (or standardisation in reality ) the bearing carriers actually fit the rear axle holders. But I wont be using them as they aren't up to scratch. I'll be designing new ones.

Hopefully see some more progress over the long weekend here in the UK

Jordan

 

[Clayton]

Jordan I can't wait to see this thing in a video! A buddy offered me a honda 500cc streetbike engine, for my kart frame that I just picked up. I wanna see how your kart runs so I know if it is something I wanna do.