Gear ratio for buggy

[Kgopa]

Hi guys, I am sure it has been asked before but I cant find anything with the same factors. I am busy building a buggy for 8 year old son, with 7 hp engine, centrifigal clutch and 18 inch wheels and dryweight will be about 260pounds. What will be a good ratio for a tight course with some drifting etc but also longer stretches (live on a farm) I was thinking about 10-11? I will install a jackshaft. In South Africa torque convertors is expensive so I wont go that route. I am not finished with the frame as can be seen on photos.

 

[JTSpeedDemon]

10 to 11/1 sounds great!

 

[landuse]

Hi guys, I am sure it has been asked before but I cant find anything with the same factors. I am busy building a buggy for 8 year old son, with 7 hp engine, centrifigal clutch and 18 inch wheels and dryweight will be about 260pounds. What will be a good ratio for a tight course with some drifting etc but also longer stretches (live on a farm) I was thinking about 10-11? I will install a jackshaft. In South Africa torque convertors is expensive so I wont go that route. I am not finished with the frame as can be seen on photos.

I would also go with a ratio somewhere in that ballpark. Just remember that with a CC clutch, you are going to have to have the right ratio so that it doesn't burn up. With 18" wheels, you will always need to gear real low. I would go with that ratio and just see how it works out for you.

Where in SA are you from? I am in Pietermaritzburg

 

[itsid]

11:1, NOT 10:1 I'd say..

260 dry, plus kid, oil, fuel, safety gear ...
330 will likely be hit fueled up and seated, and that'd require 10.4:1 already
350 lbs and we're at 10.7:1 min ratio
370 lbs and 11:1 is the minimum ratio I'd consider reliable.
thanks to the large wheels.. not nearly enough torque to break traction and drift.
(well on gravel maybe.. )

And since I assume the plan is to keep the kart for a few years..
and I certainly don't need to tell you how quickly kids are growing these days..

just skip the dry cent clutch and for the price of two of those (roughly)
buy a clone series30 TavKit on ebay
with that you can move 550lbs+ at 10:1 no problem
(it's also a tiny bit faster and what's more important gives you the low end grunt to crawl over some sticks and stones when needed. maybe even break traction )
and yeah I know expensive to ship..
maybe find a chinese seller (alibaba/aliexpress etc.. in case ebay fails to provide one)
Some are also listed on amazon, take a good look around... it's well worth it.

'sid

 

[landuse]

I just had a look on the Aliexpress app on my phone and searched for "torque converter go kart". I came up with quite a ew options that look cheap enough for even us South Africans. Some were suspiciously cheap but I have bought from Aliexpress before, and I have never had any issues in the past with scams or things not arriving. Some stuff that I have bought in the past has had some customs duties added on that needed to be paid at the post office, but it has never been huge. I am not too sure what the duties would be on a TC though, but it might still work out cheaper than buying it through Ebay etc etc.

Edit: I just checked shipping, and that is where they are going to get you. Shipping is basically the same cost as the item, and then also maybe customs duties. So it might not be as cheap as you might think.

 

[Kgopa]

I would also go with a ratio somewhere in that ballpark. Just remember that with a CC clutch, you are going to have to have the right ratio so that it doesn't burn up. With 18" wheels, you will always need to gear real low. I would go with that ratio and just see how it works out for you.

Where in SA are you from? I am in Pietermaritzburg

Thanks, I think i must start with 12 and then move my way down from there. I am from Harties in NW

---------- Post added at 07:01 AM ---------- Previous post was at 06:51 AM ----------

11:1, NOT 10:1 I'd say..

260 dry, plus kid, oil, fuel, safety gear ...
330 will likely be hit fueled up and seated, and that'd require 10.4:1 already
350 lbs and we're at 10.7:1 min ratio
370 lbs and 11:1 is the minimum ratio I'd consider reliable.
thanks to the large wheels.. not nearly enough torque to break traction and drift.
(well on gravel maybe.. )

And since I assume the plan is to keep the kart for a few years..
and I certainly don't need to tell you how quickly kids are growing these days..

just skip the dry cent clutch and for the price of two of those (roughly)
buy a clone series30 TavKit on ebay
with that you can move 550lbs+ at 10:1 no problem
(it's also a tiny bit faster and what's more important gives you the low end grunt to crawl over some sticks and stones when needed. maybe even break traction )
and yeah I know expensive to ship..
maybe find a chinese seller (alibaba/aliexpress etc.. in case ebay fails to provide one)
Some are also listed on amazon, take a good look around... it's well worth it.

'sid

You make some valid points! What I found out is that the Tc is about 3.5 times more expensive here than the CC, and the other problem is shipping to SA if it goes through the Postoffice you can wait months ( if you ever receive your package) I think I will start with 12:1 and then go higher from there. Would a diy belt slip clutch be more reliable than the cc, see alot of farm machinery use them?

 

[itsid]

Edit: I just checked shipping, and that is where they are going to get you. Shipping is basically the same cost as the item, and then also maybe customs duties. So it might not be as cheap as you might think.

hm.. 515ZAR are ~ 30 of my unitycoins or 35 freedomunits
twice that is 60€ or $70...

I paid 120 for my TC back when chinese copies weren't as popular
as they are today.
just sayin'

Still worth it...

A belt clutch is actually worse
(it's just the only cheap reliable method for a vertical shaft)
manually actuated might be a good idea but then again.. why the hassle.

I still think the TC is your best bet.
ubuy lists a TC.. and they have it at your door within a week
(they say)
https://www.ubuy.za.com/catalog/product/view/id/10156716/?variation=B07G2V5J16
IDK what they ask for shipping (lack of SA address )
but if it's 515 or less.. I'd go for it.
you might want to check other chinese websites alike (wish, gearbest etc. etc..)
some even offer free shipping every now and again.
(well they do around here that is)

'sid

 

[landuse]

I still think the TC is your best bet.
ubuy lists a TC.. and they have it at your door within a week
(they say)
https://www.ubuy.za.com/catalog/product/view/id/10156716/?variation=B07G2V5J16
IDK what they ask for shipping (lack of SA address )
but if it's 515 or less.. I'd go for it.
you might want to check other chinese websites alike (wish, gearbest etc. etc..)
some even offer free shipping every now and again.
(well they do around here that is)

'sid

So I looked at the ubuy listing and put my adress in (fake but close enough) to see what shipping would be. The pic below is what it gave me. Not too bad actually.

I just wonder what customs duties would be on it though, and it is hard to know until it is actually here

 

[itsid]

can't you just ask your duties office?
ours has a website that lists nearly all options and tells you what percentages apply to what item in general..
and ways to contact in case you still don't know
can't find such list or dedicated contact on sars.gov.za but maybe I'm not looking hard enough

for a 60€ item (funny enough.. shipping fees do count)
it's in the 12€ realms if properly declared, so not too bad..
differnt countries different rules of course,

but in gerneral I think it's ~26.5% in south africa, no? (10% import, then 15% VAT)
that'd be 247.78 ZAR if they do count shipping fees as well (slower shipping).

*shrugs* I can't tell,
but yeah it's still way less than what I happily paid for mine

'sid

 

[landuse]

can't you just ask your duties office?
ours has a website that lists nearly all options and tells you what percentages apply to what item in general..
and ways to contact in case you still don't know
can't find such list or dedicated contact on sars.gov.za but maybe I'm not looking hard enough

for a 60€ item (funny enough.. shipping fees do count)
it's in the 12€ realms if properly declared, so not too bad..
differnt countries different rules of course,

but in gerneral I think it's ~26.5% in south africa, no? (10% import, then 15% VAT)
that'd be 247.78 ZAR if they do count shipping fees as well (slower shipping).

*shrugs* I can't tell,
but yeah it's still way less than what I happily paid for mine

'sid

You are assuming that our government departments actually know what they are talking about..... and that they will even pick the phone up when you call And if you do get hold of someone on the phone, they will be totally useless and try transfer you to the next useless person just so that they don't have to deal with you anymore.

I have never seen any published lists of duties on items, and if it did exist, it would probably be 10yrs out of date and not have what I am looking for anyway.

You get used to the ineptitude of the government here. It is sad that we have to get used to such lack of service and totally useless workers....but that is just how it is here at the moment. Don't even get me started on Home Affairs and the traffic department

 

[karte_m0lim]

when I bought TC from aliexpress it cost me almost as whole kart ..

60 $ for TC, 60 for shipping .. then 12% import tax on both..

and then VAT of 25% for all ...

that wasn't enough, they charged me extra cose I didn't provide all papers within deadline, as I didn't have EORI number ..

so I guess, nobody can be worse than my government ..