New guy needing help please!

[89budget50]

Hello all! My son decided he wanted to build a go kart, so here we are! I picked up a Yerf dog roller for us to build with no real knowledge on what I needed. I then picked up a Manco frame with a bunch of parts and a brand new motor. Our intention is to assemble the Manco and sell it off as a roller and put the motor on the Yerf dog. I'll preface this by saying I am totally new to go karts but I'm a pretty good wrench!

One thing that immediately is puzzling me on the Yerf Dog is the way the rear axle is set up right now. Everything I've read and seen, shows a sprocket on the axle. I've read about torque converters having both a drive and a driven unit using a backing plate and chain. This set up has what looks like a driven unit attached to the axle. Where they intending to mount the motor and just use a belt to drive the axle with no chain? Also, there appears to be a brake disc attached to the driven unit. I can't find a name or part number on this anywhere to point me in the direction that the previous owner might have been going.

Any help will be greatly appreciated!! Hopefully the photos work!

Thanks!!

 

[BigWes]

What? Um, ok, so I have had quite a few adult beverages to offset a long tough work week...please say this ain't so! Also I just lost a long post to this thread. So someone really did this...wow. OK, so let's just throw gear ratios to the wind. Sir, you were indeed correct to question this setup. Will it work? It might with enough power and torque...but it wont be right.

I absolutely have never seen anything like this before. Thank you for showing us this!

There are for sure Yerf Dog pros on this forum that can help you out. Admittedly, I am not one. But all things being equal you know that ain't right...so you smart enough to know what is going on.

The engine should be driving that clutch on a seperate plate called a jackshaft plate, and from there the jackshaft plate should be running a chain from the driven jackshaft plate down to the axle shaft...I'll see if I can fins something similar, although not exactly what fits your needs....but you already know this...or you wouldn't be here...good on you OP!

I think with the help from the Yerf dog guys on this forum they will surely get you on the right path and have you smoking the tires in no time!



I know this pic sucks, but notice the engine is driving a belt to the driven sheaves on the jackshaft...it is powering a sprocket with a correct ratio that drives the sprocket on the axle shaft. My apologies for a poor pic, but this is a pic of my own junk and not sourced from the net...the driven should not be on the axle. You will have nothing but burnt up belts and headaches with it setup like that.

You can fix it right though. And there are good folks here that can help you!

 

[Karttekk]

Parts and support wise you might be better off flipping the YerfDog then keeping the Manco, depending on what kind of shape the Manco is in. YerfDog has been out of business for some time, Manco is now American Landmaster where most parts can still be obtained, online manuals are available and they have good support. The YerfDog may end up being more involved to correct than originally hoped.

 

[Smerft85]

Parts and support wise you might be better off flipping the YerfDog then keeping the Manco, depending on what kind of shape the Manco is in. YerfDog has been out of business for some time, Manco is now American Landmaster where most parts can still be obtained, online manuals are available and they have good support. The YerfDog may end up being more involved to correct than originally hoped.

If I parted with every kart that had an axle issue, I'd be out of karts. It can be resolved easy enough by putting it together correctly, then he would have two pretty nice karts!

If the rear axle is your biggest concern, which it rightfully could and should be, the kart is worth doing right, worst case is probably a new live axle kit, best case you pull that axle, remove the driven, add a jackshafts and sprockets, the backplate for the cvt and install it all correctly. Either alternative I think is better than parting with it over relatively small work.

 

[Randy H]

https://www.bmikarts.com/search_results.html?k=Jackshaft&search=

There are a number of solutions, that are inexpensive.

Looks like you have a snowmobile driven clutch. So you might be ahead to get one of the el cheapo Comet Tav2 knockoffs on the ebay. Depending on your engine choice.

PS, if you are interested in selling that driven I would be interested.

I've got extra aluminum sprocket carriers also if your into trading. I have aluminum split sprockets too.

 

[Smerft85]

https://www.bmikarts.com/search_results.html?k=Jackshaft&search=

There are a number of solutions, that are inexpensive.

Looks like you have a snowmobile driven clutch. So you might be ahead to get one of the el cheapo Comet Tav2 knockoffs on the ebay. Depending on your engine choice.

PS, if you are interested in selling that driven I would be interested.

I've got extra aluminum sprocket carriers also if your into trading. I have aluminum split sprockets too.

I think it's a 40 series driven, looks too small for a snowmobile driven, the two I have are like 18" diameters. Otherwise sounds like you and I are saying the same thing, should be a reasonably priced repair and worth keeping the kart.

 

[Randy H]

The first pic is a 40 series driven, The next two are a 780D.

The 700 series can be used with a 780 drive or a 94c. If your making serious power that's a good way to go. But not cheap.

I don't know for sure which clutch the OP posted in his pics. But I'd be willing to bet a wooden nickel it's not a 40 series. Haha.

 

[Smerft85]

The first pic is a 40 series driven, The next two are either a 770D 780D 790D. I'm getting oldtimers disease, can't remember.

The 700 series can be used with a 780 drive or a 94c. If your making serious power that's a good way to go. But not cheap.

I don't know for sure which clutch the OP posted in his pics. But I'd be willing to bet a wooden nickel it's not a 40 series. Haha.

May not be a 40, but still think it's too small at least for most snowmobile applications, I'm not a huge snowmobile guy, but it's way smaller than what I have on my 580's, maybe a kids sled, or something older with less power?

 

[Karttekk]

If I parted with every kart that had an axle issue, I'd be out of karts. It can be resolved easy enough by putting it together correctly, then he would have two pretty nice karts!

If the rear axle is your biggest concern, which it rightfully could and should be, the kart is worth doing right, worst case is probably a new live axle kit, best case you pull that axle, remove the driven, add a jackshafts and sprockets, the backplate for the cvt and install it all correctly. Either alternative I think is better than parting with it over relatively small work.

YerfDog went out of business partly due to some major recalls on failed welds. Shoddy workmanship could have played a part. I always look at parts availability, good support and robust machines personally. The link mentions laptop batteries as a separate recall.

https://www.cpsc.gov/Recalls/2005/cpsc-battery-biz-announce-recall-of-notebook-computer-batteries1

 

[Smerft85]

And manco had recalls too, two scalping injuries, one dead if I recall. Point being is that the aftermarket solid axle isn't likely to be original parts anyway, if he even has to replace it. From the sounds of things he has a welder and some other tools, and fixing what he already has may be possible. For example, I have a live axle that was cut in half that belongs to a dingo which I'll be welding back together. Tossing the entire kart, or selling or whatever probably isn't needed, and finding official yerf dog or manco parts isn't just opening a catalog, some stuff has to be fixed or built from scratch. Or maybe he could search Craigslist and other sites for a second matching kart for parts and fix what is needed that way, not sure what you are trying to prove me wrong on, I'm simply saying ditching the project over one problem is ridiculous, and there are solutions. Now can we get back to HIS questions and helping him out? Or must we keep beating a dead horse?

 

[Randy H]

I think the only mistake would be to sell either of them. Of course I'm a major hoarder.

Seriously it would make a nice kart with suspension. Ugly welds on that added plate. But likely strong enough, and with a little grinder attention it should be just ducky.

Manuals here. And a variety of Yerfdog parts at Bmikarts.com.

https://www.bmikarts.com/Yerf-Dog_ep_44-1.html

If the OP's model came with an industrial type engine. Then duplicating the slots and slapping on another industrial type engine shouldn't be too tough.

 

[Smerft85]

I think the only mistake would be to sell either of them. Of course I'm a major hoarder.

Seriously it would make a nice kart with suspension. Ugly welds on that added plate. But likely strong enough, and with a little grinder attention it should be just ducky.

Manuals here. And a variety of Yerfdog parts at Bmikarts.com.

https://www.bmikarts.com/Yerf-Dog_ep_44-1.html

If the OP's model came with an industrial type engine. Then duplicating the slots and slapping on another industrial type engine shouldn't be too tough.

Thank you, this is all I was trying to point out. The parts are available, but I don't think any of them are "o.e.m." to either company, but someone still makes parts.

 

[Randy H]

I don't know if this is the correct unit. But if it is, it would be a simple fairly inexpensive solution.


https://www.bmikarts.com/Swing-Arm-for-Go-Kart_p_1877.html

 

[89budget50]

Thank you all for the help so far! Sorry for the delayed response but life keeps me pretty busy right now!

I think the winners are the snowmobile driven. My neighbor came over Saturday to borrow a tool and see the latest project. As soon as he saw it, he said it looks like one he used on snowmobiles. When I sold the Manco, the buyers said the same thing. Still not sure what model the driven is.

Yes, we sold the Manco! I kinda wanted to build them both, but the kids were not on board, they just want the Yerf! It served its purpose, we got the new motor basically for free!

Randy H: thanks for posting the links and if you are serious about some trading, I’m definitely interested. Tell me what info you need on the driven to see if it will work for you.

The plan now is to get a sprocket, torque converter kit, either disc or drum band brake and mount the motor. I’m going to try to clean up the existing mounting plate they put on, otherwise might just have to cut it off and reuse the original that’s underneath it.

Any and all suggestions/comments pleAse keep them coming! I have to figure out sprocket sizes now and which brake system to go with!

Thanks again everyone!

 

[Budget GoKart]

Parts and support wise you might be better off flipping the YerfDog then keeping the Manco, depending on what kind of shape the Manco is in. YerfDog has been out of business for some time, Manco is now American Landmaster where most parts can still be obtained, online manuals are available and they have good support. The YerfDog may end up being more involved to correct than originally hoped.

Well yerfdog it's self went out of business but bmi karts owns it now so you can still buy parts the manco parts are hard to find now (in Indiana at least )