2017 - Shifter Kart - DNF

[Ebrownie]

Use valve springs.

Well clone engine valve springs would be way too light, and small block chevy springs would probably be too heavy. It's not a problem to buy springs off eBay that fit it.

 

[JMINDY]

Would the 2" Manco Spindle Springs be long enough? They are fairly stiff...
http://www.gokartsupply.com/spindles.htm

I'd bolt a Chevy axle cone-shape bump stop off of the angle iron, pointing down between the springs to the bearing housing.

 

[Ebrownie]

So I've decided to use the engine off of that 1998 Honda CR80R that I bought for $35 a while back. It needs a full rebuild, so I sent the cylinder off for a replate to EGR in Wisconsin (second pic zoom in to see the damaged part of the cylinder).

The rebuild kit is on its way, and I bought a Tusk crankcase splitter to split the case (dirt bike engines have a 2 piece crankcase that is split down the middle). The splitter is $60, but I would rather do it right than try to pry it apart and damage the gasket surfaces on the aluminum. And it's universal so just another tool to add to the collection.

When it's running again, it will make around 18-20 hp and it's a 6 speed so it should be pretty sweet

 

[Ebrownie]

I decided to add on a support piece on each side of the frame to strengthen it and IMO, it also makes the frame look better.

The 3rd and 4th pic is how I made my spindle brackets. My grandpa had these old skid plates or something from his baler that were all beat up and bent. So I cut all of the extra metal off until I got 2 identical brackets. I could have made some myself, but these things are pretty heavy duty and are already welded up and square. Still need to weld the brackets to frame and waiting on front springs.

 

[bob58o]

Instead of stiffer springs, what if you added a third bearing in the middle with two more springs?
The third bearing seems like it might also help keep things from bending. I don't know jack about this stuff, but it makes sense in my head. That is usually not a good thing!

 

[Ebrownie]

i took the engine completely apart. Split the case, removed all the internals, and removed the bearings. I got the bearings out by using a heat gun on the case to expand it just a bit and then lightly hammering the bearings out. Everything looks good inside, except for the serious heat damage on the crank and main bearings, which i expected. I have the full rebuild kit, and I will put the case halves in the oven soon and freeze the new bearings, then install them.

I also got the cylinder back from being Nikasil replated, and it looks great. The engine should be running in a couple weeks.

I also worked a little on my shifter/clutch lever. It's just a cut off handle from a bicycle with the dirt bike clutch lever on it. It will pivot around a bolt and have a linkage on it that will shift the transmission. Pretty simple.

 

[ezcome-ezgo]

The 3rd and 4th pic is how I made my spindle brackets. My grandpa had these old skid plates or something from his baler that were all beat up and bent. So I cut all of the extra metal off until I got 2 identical brackets. I could have made some myself, but these things are pretty heavy duty and are already welded up and square. Still need to weld the brackets to frame and waiting on front springs.

Those are substantial, but does this area not concern you?

 

[Ebrownie]

Those are substantial, but does this area not concern you?

Oh these pictures are older. Since then I ran a weld on those joints so it is really solid now

 

[bob58o]

Pics or it didn't happen

 

[Ebrownie]

Bob, anything to make you happy I guess

Also, my front tires came in. I bought them off amazon for like 25 bucks apiece, they are Carlisle 16x6.50-8. They are only 2 ply, but they should work just fine. They will go on these rims I got for free a while back from a John Deere lawn tractor. They don't look good but once I sand all of the surface rust and old paint off, then repaint, they will be just fine.

Since those rims just had greased low-speed bearings in them, I took those out a while back and put 2" OD 1" ID sealed ball bearings in instead. I also cut some 2" OD aluminum tubing to length and hammered it into the middle as a spacer since the bearings weren't flanged. So the bearings are nice and flush with the hub edge and won't be able to slide in the hub.

 

[ezcome-ezgo]

This is good stuff.

 

[Ebrownie]

Sorry for the very long post

So today I borrowed my friend's milling machine to 'fishmouth' the spindle axles so I can weld them to the spindle bore. The OD of my spindle bore is 1", and so is my axle (I just cut the extra off of the 72" that I bought for the rear).

So we used a 1" 4-flute end mill and drilled through the axle after centering it. They look awesome, so now I just have to cut them down to the right length and weld them on to the spindle bore.


I also made a crankshaft puller to reassemble the engine. Basically, this sucks the crankshaft into the main bearings without having to hammer or force it on. It makes sure the crank stays true and the case halves aren't twisted or deformed in some way.

You can buy a tool for this, but it costs $60, plus an adapter for the specific engine. So, I made a tool that works just as well for $5 with 1-3/8" tubing, 3 washers, 5/16" all-thread, a metric nut for the crank, and two 5/16" nuts(one is a long nut). I already had the tubing and washers.

I silver brazed the metric nut to the long nut, so one end screws onto the crank and one onto the allthread. Then I will just put the tubing over the crank end and run the all thread inside the tubing, with washers on both ends. The other 5/16" nut goes on the thread above the tubing, and when I turn that in, it pulls the crank through.

I tested it by putting one of the old bearings back onto the old crank. It worked really good and wasn't hard at all (last two pics is before and after pressing bearing on)

 

[Ebrownie]

So I've been looking into what I am going to use for my floor pan, and I decided I really want to use aluminum diamond plate. I think it would look really sweet with an orange frame.

Anyway, aluminum diamondplate is very expensive, so I am deciding on that or just steel sheet metal. I would obviously have to rivet or bolt the aluminum on, but I could weld steel. Have any of you guys used aluminum diamondplate for a floor pan? I was thinking either 3/32" or 1/8".

 

[Ebrownie]

Today I welded the spindle bores onto the front axles. They turned out pretty square; one is perfect and the other is just the tiniest bit off 90 degrees. My spindle bore tubing is 1 1/2" long. I welded the axles offset on the tubing so there was room on one side to weld the steering arms on. I still need to cut the axles to length, though.

I also wire wheeled the front rims and got all the loose rust/paint off. Then I primed and put a couple coats of black rattle can paint on them. obviously it's a pretty cheap paint job, but this should last a couple years and it looks good enough for me.

 

[Ebrownie]

Well after several hours in the shop, I now have a sorta rolling chassis with no steering yet!

First I mounted the front tires on the rims. This may seem easy enough, but it was a pain in the rear to get them on by myself. I ended up having to stand on the tire while using 2 screwdrivers to get the tires on. Then I had to touch up the paint where I scratched the rim with the screwdrivers.

After that was over, seating the bead was easy. I just put a ratchet strap around the tire, soaped up the rim and tire, took out the valve in the valve stem, and filled it up fast until it made 2 real loud pops.

Then I welded on my spindle brackets. I put them at about 12 degrees of caster, no camber. Next, I cut the spindle axles to length, made some 2" spacers between the rims and spindle bores, and put it all together with washers, bushings and the springs. Last, I put lock collars on all 4 wheels (I will need 2 more for the rear).

The front suspension doesn't have much travel, but the springs are much better than on the back. Both the spindles are identical, everything fits snug and works how it should.

 

[Ebrownie]

Made decent progress on the front end today. I welded the steering arms onto the spindle bores. For the tie rods to clear the frame, I had to make the steering arms parallel with the frame, so they are at an angle to the kingpin with the caster being 12 degrees. I didn't get to use a milling machine this time to fishmouth them, so I just drilled them to 1/2" and used an angle grinder the rest of the way (it's just 1/8"x1 1/4" flat bar). Then I drilled a 3/8" hole in the other end for the tie rod connection. They turned out nearly identical.

To get them level with the frame, I made a jig out of flat bar layed straight across the frame behind the spindles. Then I just layed the arms flush with the jig, around the spindle bore, and at the correct angle for Ackermann.

After that, I realized that I am an idiot and my brackets didn't allow enough room for my arms to turn the tires more than like 1/2" because the kingpin is so close to them. So I ground a large notch in each arm for clearance so now it steers both directions very well.

Last, I decided to put a tie rod between the two just to test the Ackermann and so the kart would roll around without going duck footed. For all of my tie rods, I have 3/8" rod, and I just thread the ends with a 3/8-24 die nut. It is hard to get perfectly straight on the threads, but it does the job and the Heim joints thread on great.

In second pic, the level thing sitting on the flat bar measures the exact angle (to the degree) of a surface. It works awesome!!!!

As you can see in last pic, Ackermann works great
Also, I won't be able to work on the kart for the next week because I am bringing it as a welding project (I am in 4-h) to our county fair.

 

[ezcome-ezgo]

Hope you get a blue ribbon! Those welds look great.

 

[Ebrownie]

So today I was thinking about how I could improve the water cooling system for the engine for the kart. These engines run hot, and I would like to improve its reliability a bit. I happened to find a heater core from my dad's old powerstroke that he sold a while back, and he said I could have it. So this is probably gonna be my kart radiator, if I can figure out a system with a little external tank with a cap (ideas would be great)because the core doesn't have a cap. The heater core is almost twice the size of the stock bike rad, (not only larger but 1/4" thicker) and IMO will look way better on the kart sitting next to the engine.

As you can see in pic #2, the bike radiator also has quite a few more bent or damaged fins than the heater core.

Also, I am going to put a 12v 12ah SLA in the kart to power both a little 7" 36w lightbar up front, and a cooling fan for my radiator. I figure if I want to run the kart a bit while it is just sitting there, a cooling fan would really help me out. The fan I am looking at is pretty high draw (almost 7 amps) so I will use it sparingly. I figure it will be a great addition for $20 though, because I am already gonna have a battery.

Here's the fan I am looking at: http://m.ebay.com/itm/311834716237?_trksid=p2141725.m3641.l6368&_mwBanner=1

Well, now you guys know all of my secret addition plans... oh well

Last, My frame got grand champion welding project at the fair! Better than a blue ribbon I would say.

 

[ezcome-ezgo]

Grand Champion! Way to go Man! That's awesome!

 

[Ebrownie]

Welded up the frame for the seat. The seat is just going to be plywood, foam, and vinyl. I may add on side support things on each side of the bottom.

I welded the backrest on at about a 20 degree angle from vertical. I've never measured what most karts are, but it seems about right, at least for me anyway.