Yerf dog build

[gtmud]

Ok, Daughter killed 6.0 Tecumsin( broken valve keeper, bent push-rod, valve to piston...OUCH) This was due to her running wide-open when torque drive stuck in low range. So I am rebuilding it.
Finished all the welding and now to the drivetrain. I purchased a Preditor 212, after Iread some good reveiws. Now to mate it to the cart. I want to replace the clutch and torque drive( worn-out) I was told that I could not use the TAV2 system due to the shortness of the crank(2.43") vs. 3.0" on the Tecumsin. So my question is should I replace the original equipment with like items, I think it has the series 20 comet clutch and Max2 driver. My daughter is only 6 and rides on mostly level sufaces with some hills fo sand(florida). $$ is tight so want to buy only what I need. I have ben on both USA Kart and BMI. What do you all recommend.
Oh the cart is a independent front suspension with a solid rear axle(no swing arm) 2 seater (yellow) built I think in 1992. I want to build this for her to have fun with her and her freinds and maybe hang a little with the smaller 4 wheelers too.
Thanks reading this.

 

[r_chez_08]

Tav2 will operate fine on a predator.
Can you not rebuild the two pulleys form the old ctv?

 

[B man]

Are they old max-torque clutches?

 

[gtmud]

I think that the Driven unit is a Maw but not sure, I have the kart parts manuel here are the #'s, Driver is a Q43201W and the Driven is Q43200W. I think these are original items, the driver says COMET stamped into the cover, the Driven has no markings.
I really wanted to use the TAV2 system, but I can't afford to drop $200 and find it wont work. I am really worried about the spacing, with the Preditor shaft and the Comet Driver mounted flat against the crank it is still only about 1/2 to 3/4 of the way threw the driver.
Thanks for the quick responces. Ken

 

[gtmud]

VERY IMPORTANT DISCOVERY!!! This only after I bought the 212 Preditor engine and ordered the driver/driven units... The engine will mount right to your original jack-shaft plate BUT you will have to reconfigure the final drive. This I mean is that instead of the drive gear located between the Driven and the jackshaft, it has to be re-located to the other side of the jackshaft and a key slot cut into the jackshaft to lock it into place. Then you will need to take the main sprocket off the axle, relocate it to the other side of the engine plate, cut a key slot and mount. The chain length should not be effected seeing that the jack shaft location hasn't changed. I guess you could just flip the axle around and relocate the drum brake..
AUGHHHHHHHHHHHHHHHHHHHHHH!!!!!!!!!!!!

 

[gtmud]

Ok did a little work last night, found that flipping the axle idea works, just have to slide the sprocket about 1/4" to get the clearance for the chain to go past the mounting plate. Another thing is that I have to raise the engine about 1" to get the sprocket to clear the engine cover. This and still able to reinstall the "basket" on the rear over top the engine. I know that with the lift I will have to add a couple links to the chain but that "SHOULD" do it. This would be a good time to install a mechanical disk brake, but $$ is tight. So to mount the drum I am going to reposition it and drill 2-5/16'" holes only about a 1/8" deep into the axle. This will allow me to "bolt" the drum into place. Could weld it, but that is too permenant, not to mention the distortion of the drum from the heat of welding.
So this is my new nightmare, abit more involved than I anticipated but I guess thats to be expected. To anyone who reads this, I beleive if I had a swing-arm rear suspension it would all be differant, but with the solid rear this is what I am having to do to make a Preditor 212 work correctly. All this MAINLY due to the shorter crank shaft. I really can't complain though.. $100 +$20 for the 2 year warrenty.. its worth it.
Anyone with ideas are welcome..

 

[j.concepcion54321]

do you have any pics that you could post of the project so that i can see what your dealing with?

 

[landuse]

So to mount the drum I am going to reposition it and drill 2-5/16'" holes only about a 1/8" deep into the axle. This will allow me to "bolt" the drum into place.

Just remember that drilling into your axle is going to weaken it in that spot. Any sort of stress could make it go 'snap' in that place

 

[OzFab]

Could weld it, but that is too permenant, not to mention the distortion of the drum from the heat of welding.

...not to mention what it will do to your axle. Landuse mentions the damage that could occur from drilling into your axle; welding creates a bigger hassle. The best idea is to use grub screws & only drill a dimple into the axle... Providing the drum has enough meat to grab them.

The golden rule with axles: Never, ever, ever, ever, ever, ever, ever, ever, ever, ever weld anything to an axle; we curse people who do this every other day

 

[Mcbreja]

The golden rule with axles: Never, ever, ever, ever, ever, ever, ever, ever, ever, ever weld anything to an axle; we curse people who do this every other day

Yes, yes we do...

 

[gtmud]

No worries, found a machine shop had jack shaft re-keyed and I was able to make my own keyway for the drum brake. Everything is relocated, now as long as I get my drive and driven in tomorrow I might be up and running by tomorrow night!! Waking up the neighbors!! Will post pics when able. Just hope I have enough links for the chain when I raise it about an 1" to clear the sprocket and chain. Wish me luck!!! Thanks for the inputs, really appreciated.

 

[landuse]

No worries, found a machine shop had jack shaft re-keyed and I was able to make my own keyway for the drum brake. Everything is relocated, now as long as I get my drive and driven in tomorrow I might be up and running by tomorrow night!! Waking up the neighbors!! Will post pics when able. Just hope I have enough links for the chain when I raise it about an 1" to clear the sprocket and chain. Wish me luck!!! Thanks for the inputs, really appreciated.

Good work. I am glad you went the right route. You will now be able to change everything easily if you ever decide to

 

[gtmud]

Almost there, I have the engine setting on the frame and the chain set on the jackshaft. Problem though, The way the Preditor front cover is designed no matter what I do the chain is making contact with the bottom of the cover. I removed the cover and replaced the engine back on the frame and it clears. So thinking of "modifying" the cover to allow for the chain to pass under it. The engine and jack plate are setting on a 3/4" spacer(this to clear the sprocket and to get me the best angle on the chain and still line up with the original mounting points) Before I make the modification to the cover do you all have any insite to other possible solutions? It was about 12am when I stopped working on it.

 

[landuse]

Almost there, I have the engine setting on the frame and the chain set on the jackshaft. Problem though, The way the Preditor front cover is designed no matter what I do the chain is making contact with the bottom of the cover. I removed the cover and replaced the engine back on the frame and it clears. So thinking of "modifying" the cover to allow for the chain to pass under it. The engine and jack plate are setting on a 3/4" spacer(this to clear the sprocket and to get me the best angle on the chain and still line up with the original mounting points) Before I make the modification to the cover do you all have any insite to other possible solutions? It was about 12am when I stopped working on it.

Could you post a pic of where the chain will touch the cover. I just cannot picture what you are trying to explain

 

[gtmud]

Not able to take pic right now, I'll try to explain it better. The front cover(pull start) it runs flat along the bottom of the engine then turns up at the bolt point to cover the cylinder and coil. At about 3" forward of that bolt is were the chain starts to hit the cover and angles up from there to the jack shaft/sprocket. (If your looking at the cover the bolt I am referancing is the bottom bolt to the left) I know I could move the engine forward some but not far enough before it interferes with the seat. I guess I could make some sort of off-set engine mount plate. Bolt the plate the the go kart frame then bolt the engine to the plate in a differant location to give me the least amount of interferance.

 

[gtmud]

I had another idea... Looking at BMI web site.. What if I moved the axle down about 3/4". This would solve almost all my issues with clearance, sprocket alignment. I really need to replace the axle bearings and the retainers are worn out fom the previous owner ( axle moves side to side) I could weld the new brackets to the originals to help with the strength issue. For $20 + shipping I could have all my problems remedied! Could it really be that simple!!!!!!!!!

 

[landuse]

I think at this stage we are going to have to demand some pics of what you have. Beg, borrow or steal a camera to take some for us. It is very hard trying to answer you blind

 

[gtmud]

See what I can do..

 

[gtmud]

Yahoo!!! My drive and Driven showed up, I opted for the 6" driven unit. I am going to drop the axle 1" that should get the clearance I need for everything to work right.... bigger tires! So tonight at the very least I should have the engine mounted and the drive set installed. Rig up the throttle so my daughter can sit in it and play some. Oh and get some pics too.

 

[gtmud]

Learning experience!! Engine is bolted in place with a 3/4" spacer between the engine and the jack plate. Throttle is hooked up and working flawlessly, kill switch is wired and the oil level sensor is bypassed. I did make a mistake in ordering the belt. I ordered one for the 7" drive, not the 6", so I am ordering the belt today. Other wise with the exception of the axle all is working correctly. Bearing kit should be in tomorrow. I am keeping the 7" drive belt, just in case the 6" doesn't give her the torque that she needs.