Cheap Chinese TC? / A lesson in rushing purchases.

[Hellion]

OHV it should read. I’m surprised Fuji/Subaru got it wrong.

Au contraire, mon frère! Subaru made a few OHC engines. Similar to the OHC Honda GC series, just not vertical.
I propose Squiddy removes the valve cover for a peek and takes photos........for the unmistakable proof

 

[Denny]

All ready been sorted out and I was wrong.

 

[Hellion]

All ready been sorted out and I was wrong.

I know. I forgot to scroll up.

More photos anyway!

 

[Squiddy202]

You’re going to have to measure out and buy a custom length comet belt.

The 30 series cvt kit complete with backing plate has a non adjustable pulley spacing and belt that I’m almost guaranteeing won’t match the spacing of the custom cvt jackshaft system your in the process of making.

Next your clutch is in fact mounted inboard so you are lucky but that does not matter as your making a custom setup anyway.

Sparkwizard very well may be 100% correct your jackshaft now has a very thin driven mower style pulley and your wanting to slap on a very hefty cvt style pulley. The jackshaft you have now MAY not even be long enough.

And then we haven’t even gotten close to the point of whether you’re happy with your new CVT gearing. You may want a $20 c-sprocket that gives you more torque. Maybe it has tons and tons of power and you want to gear for just a touch more speed.

If your making a custom setup with zero parts horde your gonna have lots of unseen costs all over the build.

To be fair none of this is custom. This is what Murray explorers had it would seem. I did check beforehand and the belt size is fine as my engine mounts can move like a inch. I used the chart.

 

[Squiddy202]

Sparkwizard very well may be 100% correct your jackshaft now has a very thin driven mower style pulley and your wanting to slap on a very hefty cvt style pulley. The jackshaft you have now MAY not even be long enough.

So like how far could it hang onto the threaded section? If it is not at all then .

 

[Squiddy202]

well I tried to measure and see my chances. Safe to say it isn’t working. I have exactly 0” of distance if I use a CVT. Now I did math and accounting for the money lost from shipping the GPS one back it is ~$120 + new chain length I waste/spend to go the Amazon route. I definitely do not have a welded sprocket. I see 0 evidence of welding and I do see a set screw. If I were to get the jackshaft and use the GPS CVT it is about also $120 + shipping for the jackshaft. What do y’all think.

 

[Whitetrashrocker]

I think you need a camera.
I think you have posted only 2 pics of your kart. Neither were good angles to really see what's going on.
You have the whole group here blindly throwing advice at you and your still not any better than where you started.
I get your young and may not know the
In and out of this kinda stuff.
Pics as you disassemble stuff will help us help you more. This could have saved you money and frustration.
For all I know a $60 TAV kit and a moved sprocket would have had you ripping the neighborhood.

 

[Hellion]

What do y’all think.

WTR is right. We need lots of photos in excruciating, disgusting detail. I know you hate to do it; we're not there but photos can bring us there. Help us help you.

Dropping these here, I think they represent your particular kart....

 

[Squiddy202]

I think you need a camera.
I think you have posted only 2 pics of your kart. Neither were good angles to really see what's going on.
You have the whole group here blindly throwing advice at you and your still not any better than where you started.
I get your young and may not know the
In and out of this kinda stuff.
Pics as you disassemble stuff will help us help you more. This could have saved you money and frustration.
For all I know a $60 TAV kit and a moved sprocket would have had you ripping the neighborhood.

I do need to get better at sending pics and I think you are right. My dad was like “oh but that sounds like a lot of work and the farther from original the worse as it is harder to revert.” Either way, do you think I should go for the kit or just like buy a jackshaft?
Edit:
I can’t send them until tomorrow afternoon because of school and the fact it is dark for me.

 

[Squiddy202]

WTR is right. We need lots of photos in excruciating, disgusting detail. I know you hate to do it; we're not there but photos can bring us there. Help us help you.

Dropping these here, I think they represent your particular kart....

View attachment 160289

View attachment 160290

View attachment 160291

View attachment 160292

View attachment 160293

Looks literally just like it, minus the cage.

 

[Whitetrashrocker]

Lets step back a bit.
From your one picture it looks like you have a functional kart.
Why do you want to change things up?

In this pic you have a CC (centrifugal clutch). It uses a V belt to turn larger pulley.



In my opinion V belts dont transfer power and torque well. Just not big enough. But it does work or it would be a factory accepted way.

Then on this side there is a chain with 2 sprockets.



Back to the question of why change?

Can we get some tooth count on bothe sprockets? Use a marker and keep track. Need exact numbers.
Also measure the outer diameter of the belt pullies. Try to be exact with this.
This will give enough to give you a gear ratio.
6:1 is a good target.

Putting a TAV on it will make it feel like a rocket compared to that CC. But it will take some work and your dads kinda right about getting things too far from stock.

Will a TAV fit there? I dont know. Im blind here.
There's many ways to skin a cat. Which is right for you?

 

[Squiddy202]

Lets step back a bit.
From your one picture it looks like you have a functional kart.
Why do you want to change things up?

In this pic you have a CC (centrifugal clutch). It uses a V belt to turn larger pulley.

View attachment 160294

In my opinion V belts dont transfer power and torque well. Just not big enough. But it does work or it would be a factory accepted way.

Then on this side there is a chain with 2 sprockets.

View attachment 160295

Back to the question of why change?

Can we get some tooth count on bothe sprockets? Use a marker and keep track. Need exact numbers.
Also measure the outer diameter of the belt pullies. Try to be exact with this.
This will give enough to give you a gear ratio.
6:1 is a good target.

Putting a TAV on it will make it feel like a rocket compared to that CC. But it will take some work and your dads kinda right about getting things too far from stock.

Will a TAV fit there? I dont know. Im blind here.
There's many ways to skin a cat. Which is right for you?

Well there was one guy that said messing with ratios on a CC is a bad idea. I mean it will take some work but it is relatively simply to move the sprocket right? I think we can do the math. I am moving about 14 mph. The engine should be spinning about 3200 rpm since it was meant for like pressure washers. I have 18” diameter tires on the rear. According to the internet that is about 214 tire rpm’s. 214:3200 is ~1 : 12.260536398467. So that is more like a 12.25 to 1. Basically, is it a bad idea to change sprocket size with a CC, and why?

P.S.: Why change? Well I am going to be using my friend neighborhood to drive around as they say other people do it all the time. It is suburban with lobg winding roads and built on a golf course. For areas like that it is much more cruising so I want more speed. All in all, this guy sums it up well:

Edit: The CVT also gives great low end torque as well as accel which makes it feel fast. Gear change would lower accel.

 

[Squiddy202]

PHOTO UPDATE:
This is all I can give you until tomorrow afternoon. It is all my kart pics on my phone

 

[Whitetrashrocker]

Thas not how you figure gear ratios.

18" tires are just fine.
Whats the pullys diameters and the tooth counts.

 

[Squiddy202]

Thas not how you figure gear ratios.

18" tires are just fine.
Whats the pullys diameters and the tooth counts.

Well yeah but we can tell the diameter down to the wheels. They are mounted to the same shaft as the drive sprocket so they have the same rpm. It is just a rough estimate from the entire power train. I can’t check at night I’m in EST and garage lights suck.

 

[panchothedog]

It is a Murray explorer, it does have a live axle, I don’t know about a welded sprocket. To be honest, I already talked it over with my dad and brought the GPS one. It comes with a belt and the 3/4” driven. The prices almost equal out from Amazon. It would probably be a slight bit less if I do it the other way but not very much like at all.

I think you got the problem solved. Assuming that you also are getting ( or already have ) A 30 series driver.

 

[Squiddy202]

I think you got the problem solved. Assuming that you also are getting ( or already have ) A 30 series driver.

No, now the GPS one won’t fit as the jackshaft is too short.

 

[Sparkwizard]

Take a picture of the parts you currently have and post the picture. If you have parts coming to you now, get pictures when they get there.
Don't buy anything right now. Since it can be ridden right now, don't take anything apart. Get those measurements. Count those teeth.
Be patient.

 

[Hellion]

Why do you want to change things up?

He wants gear ratios and to go faster than 14mph that his current setup provides……

CVT vs Centrifugal Clutch

I was recently debating changing the gearing on my kart. Someone mentioned using a CVT and it seemed like a good idea. I have ~7hp, and I can only do like 14 on a 200lb kart. I really only want to get up to around 25mph. Can you even really (easily ish) convert from centrifugal to torque...

www.diygokarts.com

This thread is just a rehash of his old one. This forum gave me autism. Anyway put pictures first and maybe 1/3 of the currently active members here would have said, oh yeah I remember that kart. Didn’t we get it fixed? Another third would have remembered the VW bus next to the kart. Lol

Nothing has changed, those are the photos from the last thread.

EDIT: anyway, the parts manual I shared in post #88 (hopefully) shows us that a TC can go there.

 

[Sparkwizard]

I thought some of the conversation sounded familiar. Thanks for clearing that up, @Hellion !