Need To Put On Bigger Gear

[firealarmgeek]

Hi,

I just joined this forum tonight and am posting this on behalf of my dad. I'm not quite sure if this is the right forum for this, but hopefully I can get some help. We own 3 smaller go karts, but we also own a larger go kart/dune buggy which we've been trying to get going for a few years now, and that's why I'm posting here. I have no idea the brand of the frame, but the engine is an Arctic Cat Spirit, which is a snowmobile engine. I'm guessing it replaced the original engine. While I'm here, if anyone knows the brand of this go kart/dune buggy, we would love to know.

Right now, it starts, runs, and even somewhat drives. The problem is that it's got too much speed and not enough power. When we give it throttle, it takes forever to get it going. To correct this, my dad wants to put on a bigger gear, but what we want to know is if we can still get one of these gears that has the four bolts on it to remove, and if so, where to get it and what kind to get. What would someone on here recommend? Thanks in advance!

http://i1355.photobucket.com/albums/q712/MarkVIIIrocks/20150822_185813_zpsb5hcscyy.jpg

http://i1355.photobucket.com/albums/q712/MarkVIIIrocks/20150822_185743_zpsxamgmggz.jpg

 

[Poboy kartman]

Sorry...I can't help ya.....but....you definitely came to the right place...someone will be along shortly..

Welcome to the forum!!!! Please fill out a profile location and we can better help you source the part as this is a worldwide forum.

EDIT: BTW: Measure the distance between tooth tip to tooth tip....(looks like /2")....and the thickness of the sprockets...(looks like 1/4")....which would be a #40....but we don't wannabe guessing here, also count the number of teeth on that sprocket....we need to know what bigger is.

 

[OzFab]

Welcome to the forum...

Just from looking at your pics, the gear ratio is waaaay off; do us (& yourself) a favour & count the teeth on both sprockets & the distance between the teeth (chain pitch) then report back; while you're at it, measure the centre to centre distance between to mounting holes on the axle sprocket...

IMO, the axle sprocket needs to be bigger & the jack shaft sprocket needs to be smaller so, you're on the right track; from what I can see, the gear ratio should be somewhere around 6:1, the current ratio, I would guess, is closer to 4:1...

As for availability of sprockets, as mentioned above, please provide your location so we can better guide you to suppliers...

 

[mckutzy]

Hello and welcome...
I don't have much to say other than what already been said...

But I am interested in your hawk cb400 in the background ... Or is it a 350? I have a cb400 And wanting to getter running again.

 

[machinist@large]

Welcome to the forum...

Just from looking at your pics, the gear ratio is waaaay off; do us (& yourself) a favour & count the teeth on both sprockets & the distance between the teeth (chain pitch) then report back; while you're at it, measure the centre to centre distance between to mounting holes on the axle sprocket...

IMO, the axle sprocket needs to be bigger & the jack shaft sprocket needs to be smaller so, you're on the right track; from what I can see, the gear ratio should be somewhere around 6:1, the current ratio, I would guess, is closer to 4:1...

As for availability of sprockets, as mentioned above, please provide your location so we can better guide you to suppliers...

The camera angle flat out , but from the loose tooth count, it looks like this thing may be as low as 3 to 1..I could be way wrong (dealing with every time I try to do anything with the photos automatically tries to send me to a photo account doesn't help).....

Moderators, is there any way to keep photos that actually appear in a post from sending me to asite that I don't want anything to do with? Maybe ban those types of links?!!!?!?!?!?!!!!!!

To the OP; post it up using the forums manage attachments format. I don't have unlimited bandwidth or a data plan that matches. Use our format when posting any attachments, because I know that I'm not the only one here.

And for the record, we took a survey and voted a while back.... Third party junk flunked because of all the unwanted advertising, with the fact that most of the advertising was used to gather information that we all deemed to be none of their business.

 

[firealarmgeek]

Alright, thanks for all the replies! I will check out that information and get back.

I believe the motorcycle is a CB400. My dad purchased it last year. Just another project in the garage that he'll eventually get to. It hasn't ran in years.

 

[firealarmgeek]

I'll get the rest of the information tomorrow, but the axle sprocket is a 40 tooth, and the jack shaft sprocket is a 16 tooth.

 

[OzFab]

It's worse than I thought, that's 2.5:1, no wonder it's struggling to move the gear ratio should be at least double that...

Having said that, finding an axle sprocket alone to reach the desired ratio may prove difficult so, the need to replace both sprockets is there; by replacing the J/S sprocket alone to a 12t (if it will fit) the final ratio goes from 2.5:1 to 3.33:1; an improvement but, still not enough; based on that, the axle sprocket will also need to be replaced with one in the vicinity of 60t to give you a ratio if 5:1...

 

[2SlickNick]

I know the 39 axle sprocket is the larger upgraded sprocket for the 150 karts. So yuo will probably have better luck looking for a smaller JS sprocket and smallertires.

 

[OzFab]

Hang on, Nick, if we can match the bolt hole circle & pitch of the existing sprocket, we should be able to find something larger...

Besides that, if 39t is the largest sprocket available, how is it they have a 40t?

 

[2SlickNick]

I can't seem to find any larger than a 39t axle sprocket that will fit directly to your existing hub and axle. You might just have to use a blank sprocket
http://www.azusaparts.com/ProductPage.aspx?catID=1&subCatID=74&ssCatID=75&productID=3782

I did find a smaller JS

 

[landuse]

Welcome to the forum. I think the guys have covered most of the bases her, but definitely you need a lower gear ratio. If you cannot go low enough with what is available out there, you might have to get smaller tyres like nick says

 

[firealarmgeek]

Alright, thanks for everyone's input so far! My dad and I plan on taking off both gears tomorrow. We bought this buggy a few years ago, and the guy who put on the Arctic Cat motor completely messed up on the drive system, so that's why the gears are like this. He sold it because he had absolutely no idea what to do to make it drive.

I'm still a little bit confused, though, as to what we need to do. I understand the ratio is way off, and that we need to make it preferably a ratio of 5:1. I think my dad is willing to replace both gears, that's fine. What should the teeth on each one of them be? Is a 39 tooth the only option? I'm not sure what a blank sprocket is, and we just want to get the parts soon so we can get it going quickly. The jack shaft sprocket Nick linked me to is a 9 tooth. If we get that, how many teeth should the axle sprocket be? Of course, I'm sure it will make it harder with the four bolts. Thanks for everyone's help and patience!

 

[landuse]

To calculate gear ratio, divide the axle sprocket teeth by the engine/jackshaft sprocket teeth

 

[firealarmgeek]

I apologize for the long delay in response. Thanks for everyone's advice. I think we have it covered from here. My dad put the buggy in the corner of the garage for the winter so he can focus on other projects, but he did order the parts we need to get it going hopefully in the spring.

Thanks again, and I'll be back if we need any help!