Master Hack
Well-known member
Use a bigger wire then.
ST2-NG Pre-build "Think Tank"
- Thread starter Kartorbust
- Start date
pgemin
New member
I built an ST3 several years ago - it contains very similar plans to the ST2 NG. I asked myself many of the exact same questions you are asking.
I too miss minibuggy.net. I was a champion lurker with no posts in14 years.
In short, here are a couple of my solutions:
Brakes: I use one rear brake and added two front brakes. I had a professional welder secure the brackets for the front brake calipers. I matched the rotor bolt pattern to the wheel lug pattern. Make sure your wheel wells are big enough to handle the rotor and caliper.
Electrical: My first engine was a 1994 Polaris 650 3-cylinder converted from fuel injection to carbs and there was basically no electrical except a kill switch, spark plug wires, and a CDI. I blew that engine 14 months ago. My new engine is a 2007 Polaris 700 (I bought the whole functioning snowmobile for $2800 in February). I just got the engine fully installed and running in the buggy 2 months ago. For the electrical on the new engine, I painstakingly cut and extended the harness to the necessary locations (this was easy for me as it was similar to a job I had for several years).
Live axle: I use Porsche 924 CV axles - they are cheaper than 930's and give me 13 inches of travel. The extra width on the rear is compensated by the very wide front end (I think the plans got the total front width wrong).
Jackshaft setup: I have a dual-jackshaft setup: CVT driven pulley and 12 tooth sprocket on the first jackshaft, second jackshaft has ~28 tooth sprocket and 12 tooth sprocket, to final 46 tooth sprocket on the live axle. I don't recommend using smaller than 12 tooth sprockets on 1 inch jackshafts. The final sprocket and brake are welded to a collar that mounts on a 1-1/4 inch keyed shaft.
I have many other lessons-learned, but this should help with several of your questions.
I too miss minibuggy.net. I was a champion lurker with no posts in14 years.
In short, here are a couple of my solutions:
Brakes: I use one rear brake and added two front brakes. I had a professional welder secure the brackets for the front brake calipers. I matched the rotor bolt pattern to the wheel lug pattern. Make sure your wheel wells are big enough to handle the rotor and caliper.
Electrical: My first engine was a 1994 Polaris 650 3-cylinder converted from fuel injection to carbs and there was basically no electrical except a kill switch, spark plug wires, and a CDI. I blew that engine 14 months ago. My new engine is a 2007 Polaris 700 (I bought the whole functioning snowmobile for $2800 in February). I just got the engine fully installed and running in the buggy 2 months ago. For the electrical on the new engine, I painstakingly cut and extended the harness to the necessary locations (this was easy for me as it was similar to a job I had for several years).
Live axle: I use Porsche 924 CV axles - they are cheaper than 930's and give me 13 inches of travel. The extra width on the rear is compensated by the very wide front end (I think the plans got the total front width wrong).
Jackshaft setup: I have a dual-jackshaft setup: CVT driven pulley and 12 tooth sprocket on the first jackshaft, second jackshaft has ~28 tooth sprocket and 12 tooth sprocket, to final 46 tooth sprocket on the live axle. I don't recommend using smaller than 12 tooth sprockets on 1 inch jackshafts. The final sprocket and brake are welded to a collar that mounts on a 1-1/4 inch keyed shaft.
I have many other lessons-learned, but this should help with several of your questions.
Kartorbust
Inmate #627
What stubs were you using for the axles and did you run discs for the hubs or did you have custom hubs made to run the single disc brake?
pgemin
New member
I'll try and explain in plain English, but since this is your thread, I'll limit pictures.
Outboard Rear:
Rear stubs and hubs were from a Honda Accord (I think). I cut the stubs off like the plans said using a Lathe and put in a 1-1/4 inch dia counterbore on the back side. I welded a 1-1/4" dia section of ~5 inch long key stock to the back of the stub on the outboard side and welded the other end of the key stock to a homemade flange that mates to the CV axle. The key stock insertion was necessary to ensure the CVs would not rub on the A-Arms and to fit with the bearing uprights. The hubs were modified from 4 on 4 inch bolt pattern to 5 on 4-1/2 inch to match the plans (changing the bolt pattern was a waste of time, IMO).
Inboard Rear:
The sprocket is welded to the collar. I made a custom flange that is welded to the collar and bolted a Honda Civic brake rotor to that.
Additional important notes: I had to lengthen the rear A-Arms and mount them outboard of the bearing uprights to clear the CVs.
Kartorbust
Inmate #627
So bad news, the plan files were saved on my MicroSD card in my phone and my phone no longer can read the card. So they may no longer exist. I need to find a microSD to full SD adapter and see if I can retrieve the files on my computer. Did not really forsee this as a potential problem.
Been waiting for it to warm up more for the weekends so I can try to rebuild the Spirit engine. I'm kind of confident I can get that to work. Once it's running, I'll pull it out of the sled, sell the sled carcass or scrap it to free up garage space, then if I can get the plans retrieved, I may start building. If not, option B is get KJ Raycing VF-1 plans and build one of those with this engine.
Been waiting for it to warm up more for the weekends so I can try to rebuild the Spirit engine. I'm kind of confident I can get that to work. Once it's running, I'll pull it out of the sled, sell the sled carcass or scrap it to free up garage space, then if I can get the plans retrieved, I may start building. If not, option B is get KJ Raycing VF-1 plans and build one of those with this engine.
Kartorbust
Inmate #627
Did some inspecting on the engine for a few minutes today. Looks like if this thing runs, I think I found a spot for a starter.
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Kartorbust
Inmate #627
In other news, I was smart enough 4 years ago to email the plans to myself. My phone is being dumb and will not download them, so I forwarded them to my brother who will have redundant copies as well as a hard copy as well.
Kartorbust
Inmate #627
Still have not made any headway. Been busy with work and since summer time has hit, it's been almost too hot to even want to work on the engine. My dad got me a new ignition coil for this for Christmas, however you need to strip the plug wires and install your own spark plug boots. Anyone ever had to do such a thing? Never had to do it myself so I want to be careful as possible as to not screw it up. Any tips?
Kartorbust
Inmate #627
So on the 4th of July, I did find that the left piston has some forward and back play in it where as the right cylinder does not. Haven't checked with a feeler gauge yet. But bit concerned that the cylinder is shot. Most these can be bored out is 0.020 over, which would bring it up to I think it was 507cc. But with the bit of play, I'm not sure that even boring it out would even be enough to address any uneven wear.
Kartorbust
Inmate #627
So both cylinders are good. I was dumb and figured it was the rings. Got the chaincase cover off and the sprocket count is 21/33, so a 1.57:1 ratio. Mind you, this engine was setup to be a low revving engine of around 6500rpm or so max and had a longer stroke compared to similar sized engines. Usually sleds were geared around 2:1 or greater.
So I'll probably be ordering a complete gasket kit, plug boots, carb rebuild kit and see if I can't get this thing running at some point. The driven clutch has the spring pointed inward. Not sure if it's on a keyed shaft or splined. The sheeves at least kind of move.
So I'll probably be ordering a complete gasket kit, plug boots, carb rebuild kit and see if I can't get this thing running at some point. The driven clutch has the spring pointed inward. Not sure if it's on a keyed shaft or splined. The sheeves at least kind of move.
Kartorbust
Inmate #627
Looks like it will be almost $60p to do a complete Comet 102c and 90D swap for this. But due to how rusty the sheeves are on the driven and how much corrosion is on the Arctic Cat Hex clutch is, I'd rather do it. Plus the driven does not appear to be one that could be transferred over to a keyed 1" shaft. So swapping to the Comet will make this a lot easier. This will allow me to run a 1 3/16" belt as well, which are still commonly available. Would have to match up the centers to be dead nuts on to prevent belt wear and to just get the right size belt that would be used originally on this.
Unfortunately, I will not have mechanical reverse. Might just do without or get a large ring gear and possibly a heavy duty starter and do it that way.
Unfortunately, I will not have mechanical reverse. Might just do without or get a large ring gear and possibly a heavy duty starter and do it that way.
Kartorbust
Inmate #627
Since options are kind of limited in that, no one makes a U-joint yoke kit in a standard size for 1310 Spicer joints, I'll probably go the route of just the ones from Surplus Center that are 1.25" with 1/4" key ways. This is technically a bit larger than what the original plans call for, however, seen quite a few people on YouTube wreck 1" shafts with much higher horsepower, so I would rather be more cautious. Would do CV axles, but other than cutting them to fit, or possibly spending the money on ATV ones and getting the live axle splined to fit, think I'll take my chances with the u-joints. If those fail, then I'll modify as needed.
Kartorbust
Inmate #627
Engine is still torn apart. Haven't had time to mess with it lately. Waiting on a gasket kit to reseal the engine and then need to work on getting the carb and ignition system. Still trying to figure out how to do the kill switch and key ignition. Still up in the air what to do with the carburetor.
Another thing is, have to figure out a regulator/rectifier or how to wire one in. The lights on it are A/C which if swapped out for LED will burn then out almost immediately, then have to connect a battery to keep the lights consistent, otherwise they could have a flickering affect.
This feels overwhelming, but this is what I'll have to work through. Maybe the next post I make, will be of the engine running hopefully. Will try to document everything that I can. Parts are becoming scarce.
Another thing is, have to figure out a regulator/rectifier or how to wire one in. The lights on it are A/C which if swapped out for LED will burn then out almost immediately, then have to connect a battery to keep the lights consistent, otherwise they could have a flickering affect.
This feels overwhelming, but this is what I'll have to work through. Maybe the next post I make, will be of the engine running hopefully. Will try to document everything that I can. Parts are becoming scarce.
Kartorbust
Inmate #627
Waiting on the complete engine gasket set to go back in stock. Also finally settled on an axle set, going with VW type 2 CV axles. Going to use the transaxle flanges to mount the axles to the spool. Going to be an oddball size and will require custom parts and machining. The flanges if memory serves me right, have a 33mm diameter where the splines mate with the transaxle stubs.
So going to get the spool machined out of Chromoly and going to need a custom sprocket hub made, since far as I know, most are only made for 1" and 1.25" axles.
The front spindles will be Banshee on custom A-arms to make the front wheel offset to be a bit wider than the rears. Had been toying with the idea of doing a limited slip differential from a Miata, however Miata axles will throw the proportions way out of whack. I have glanced at more budget friendly Porsche 930 CVs, but even those are like $400.
So going to get the spool machined out of Chromoly and going to need a custom sprocket hub made, since far as I know, most are only made for 1" and 1.25" axles.
The front spindles will be Banshee on custom A-arms to make the front wheel offset to be a bit wider than the rears. Had been toying with the idea of doing a limited slip differential from a Miata, however Miata axles will throw the proportions way out of whack. I have glanced at more budget friendly Porsche 930 CVs, but even those are like $400.
Master Hack
Well-known member
When ya remove "Porsche 930" from the part and substitute VW Van, ya get this:
different part numbers but no real visible difference when compared side by side.
www.autozone.com
different part numbers but no real visible difference when compared side by side.
Duralast Gold CV Axle Assembly 8395N
Shop for Duralast Gold CV Axle Assembly 8395N with confidence at AutoZone.com. Parts are just part of what we do. Get yours online today and pick up in store.
www.autozone.com
Kartorbust
Inmate #627
It's essentially a Type 2 CV axle. Still has a 100mm. I had looked around on VW forums and found that to be the case. Looking into options for Type 4s but those are becoming rare.When ya remove "Porsche 930" from the part and substitute VW Van, ya get this:
different part numbers but no real visible difference when compared side by side.
Duralast Gold CV Axle Assembly 8395N
Shop for Duralast Gold CV Axle Assembly 8395N with confidence at AutoZone.com. Parts are just part of what we do. Get yours online today and pick up in store.
Master Hack
Well-known member
I guess l don't know the difference. Please enlighten me!
l know they work great for me.
Kartorbust
Inmate #627
So the 930 Porsche axles use a 108mm flange, which allows them to have around I think 16-18 inches of travel, which is why they are highly sought after for off road projects. Top of that, plenty of companies make different length shafts to make them longer or shorter, depending on the project. The car was the Porsche 930 and 930 Turbo.
The Type 2 bus axles use a 100mm flange and can give 10-12 inches of travel.
Type 4 which are hard to find but came in the early model 911 and 944 will do 12-14 inches of travel. The Type 2 and Type 4 have the same 100mm flange diameter and are generally swapped on to Baja Bugs and sand rails, especially when those are still using the Type 1 bug axles, which will give like 6-8 inches of travel. They make flanges that will adapt from a Type 1 to the Type 2/4 without a problem.
Now it's possible those axles are correct and could be a Type 4 and not just a standard type 2 bus. A lot of information can end up being conflicting even multiple sources seem to conflict with each other. But that's what I've been able to find.
Main difference is the bearing diameter in the flanges for the Type 2 and Type 4 that allows the most travel.
The Type 2 bus axles use a 100mm flange and can give 10-12 inches of travel.
Type 4 which are hard to find but came in the early model 911 and 944 will do 12-14 inches of travel. The Type 2 and Type 4 have the same 100mm flange diameter and are generally swapped on to Baja Bugs and sand rails, especially when those are still using the Type 1 bug axles, which will give like 6-8 inches of travel. They make flanges that will adapt from a Type 1 to the Type 2/4 without a problem.
Now it's possible those axles are correct and could be a Type 4 and not just a standard type 2 bus. A lot of information can end up being conflicting even multiple sources seem to conflict with each other. But that's what I've been able to find.
Main difference is the bearing diameter in the flanges for the Type 2 and Type 4 that allows the most travel.
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Master Hack
Well-known member
The 100mm flange worked perfectly for me cuz it fits into a 6020 bearing (100mm bore)
l have a Napa part number (somewhere) that might be different. Price was about the same. I used that pic cuz it came up first. I'm lazy.
l have a Napa part number (somewhere) that might be different. Price was about the same. I used that pic cuz it came up first. I'm lazy.
Kartorbust
Inmate #627
What did you use for the stubs for the CV axles for the wheels? I've been debating having custom subs made to adapt ATV hubs. If I recall the Megalodon by Badland just used 930 to like type 2 stubs and they used normal VW disc brakes with the old 5x205mm wide 5 bolt pattern wheels with bead locks.