Yerf dog 3203 fixxer-upper

[yerf_bug]

Hello all,

Bought my son a Yerf dog 3203 in fairly bad condition.

Since the purchase I have been coming across problems left and right and slowly replacing parts.

I plan to build it up for torque and low end power.

When we both rode it with the stock motor it stalled if you drove through grass.

As of current I have replaced the engine with a 212cc clone

cleaned up the comet 30 series

bought new belt

installed new 9t sprocket on jack shaft

and plan to purchase a few more engine mods.

just the basics like a box stock arc package or something.

plan to replace the valve springs, rod, flywheel, install header, remove governor, add intake, jet carb etc.

Right now the springs in the comet are shot IMO.

Ive read the yellow spring is supposed to add torque, but which springs should go inside the weighted unit?

Im not looking to go super fast as it is fast enough right now.

I just want to take him off roading and climb hills without having to jump out and push us.

I want him to be able to spin the wheels and cut donuts without having fear of tearing up the motor etc.

any ideas for mods and the proper springs to order for the drive and driven clutches?

looking to run around 5-6k rpm wise on the open trails but still want plenty of torque to climb the hills with about 250lbs of boys riding in this baby.

any help is greatly appreciated

 

[bandit 2026]

I noticed that a lot of people have read your post but offered no opinion, so I will put my 2 cents worth in. I don't think your going to get what you want as far as tire spinning, doughtnut cutting machine your looking for, the torque converter will just keeping shifting to a higher ratio when the wheels begin to spin and the motor you are building will over come most any spring you install. Just finished one of these myself. If you nail it in gravel it will spin for a foot or so then the converter starts to do its job. Now in snow, well thats another story.

 

[joekd]

Bury it in mud or as mentioned snow and the yerf does donuts just fine

I had a built motor on my sons Yerf kart and replaced it with a stock 6.5 electric start motor, plenty of power for him and world's easier for him to start

Here's a short vid of him having fun with his

VID00023.mp4 - YouTube

 

[trailhopper]

Sweet video. Thanks for sharing.

 

[yerf_bug]

thanks but i was able to obtain most of my engine replacement parts.

tore into this baby and did some motor upgrades, replaced the springs in the driver and driven, swapped the 10t sprocket to an 8t and I have to admit...

this is way too much kart for a 9 year old.

I weigh 200 lbs and this thing tears it up.

spins the wheels from a dead stop and tops out around 40-45 mph.

in fact today I was showing off to one of my buddies and flipped this sucker.

tried putting my leg out like I usually do and it was just going to fast.

smashed my knee joint and shin and really screwed my chit up.

im a truck driver and this is my clutch leg and my peterbilt has a tough clutch as it is.

still frickin awesome though. my buddy actually was filming me on his iphone gonna have to get that from him