Predator 301 with 40 series

301Fox

New member
Messages
4
Reaction score
0
Location
Hampstead, NC
Hello everyone!
I am new here and in need of some help. Ill give some background info as an introduction and pose my question at the end.
I bought this Fox go-kart a few years ago for REALLY cheap (under $500) as a birthday present for the kids. The little Subaru 6 HP was OK when they were on it but when they wanted me to drive and do fun stuff in the field, the 6 HP wasn't enough. I built it up to stage 2 and it was better, but with me (200 lbs) oldest son (105 lbs) and sometimes the little guy (50 lbs) plus the weight of the cart, I felt it was still lacking and I think the engine felt that as well!
Fast forward to December 2021 - Harbor Freight had a sale on the 301 CC and I happened to have a 10% off ANYTHING coupon...so that happened. I had been wanting to build a minibike and figured I can use the Subaru for the minibike. I got a welder for Christmas, made an engine mounting plate at work, got a bunch of free round/square tubing, flat bar, and some angle from my work as well and over Christmas break I got the 301 mounted. I currently have the gov bypassed, air filter, and exhaust that I welded up. I ordered a Chinese 40 series TC and it has been less than desirable. I have on order for the TC...red springs, med weights, and a reverse wound spring so I can run outboard. Been running outboard with the red because I could not mount inboard and have the belt line up correctly. Here is my question: Saturday we were cruising around and after taking a corner a little fast I experienced some axle hopping. That caused to the chain to pop off, so we pushed it home, put the chain back on, adjusted it and went out again. After this incident it seemed to be fine until I reached about 1/4 throttle and I noticed very bad vibration and a "slipping" feeling, not getting the power I was before. It will still accelerate but I can hear and feel that something is NOT right. I pulled the driver off of the engine shaft and springs, connectors, weights are good (thought something may have snapped when the chain came off and I floored it before I noticed it), no noticeable damage or burning on the belt, both sprockets are good, no cracks, no missing teeth, not bent. The only thing I have not checked and didn't cross my mind to check until I was typing this out was maybe a bent axle? Any thoughts? What am I missing? I am at a loss.
I sure do appreciate you all taking the time to read this and thank you for accepting me into the group!
 

Attachments

  • original fox.jpg
    original fox.jpg
    133.3 KB · Views: 6
  • fox 301.jpg
    fox 301.jpg
    129 KB · Views: 6

Denny

Canned Monster
Messages
11,605
Reaction score
8,037
Location
Mayberry, Indiana
Welcome, and check for broken keys and or key ways. Bent shafts and bad bearings are something else to look for.
 

panchothedog

Well-known member
Messages
2,788
Reaction score
3,739
are you sure it's on the drive system and not the engine? Did it rev so high that you might be in the early stages of throwing a rod.
 

301Fox

New member
Messages
4
Reaction score
0
Location
Hampstead, NC
I don’t think so because I drove it after that and it seems to run like it did. I’m in the process of disconnecting the TC and running the engine with no load to see what it does. I’ll keep you posted.
 

madprofessor

"Loose Cannon Creations"
Messages
2,899
Reaction score
960
Location
Jacksonville, Florida
Lots of folks swear by propping the rear wheels up off the ground (safely) and doing test revs and such to visually understand one example of what the TC is doing with no load on it. Putting load on it by applying rear brakes during a test like that tells you even more. Also a good way to check brake's action.
Best part of all that? No real work, no R&R stuff. Just jack it up, block it, lock it down, and test. Do that first, save the hard work.
 

301Fox

New member
Messages
4
Reaction score
0
Location
Hampstead, NC
Well I didn’t know that. Look at me learning new tricks! Thank you madprofessor! We have company coming over so I’ll have to wait till tomorrow to do anymore with it but I will definitely be trying that and keeping you updated!
 

madprofessor

"Loose Cannon Creations"
Messages
2,899
Reaction score
960
Location
Jacksonville, Florida
learning new tricks!
There are certain times when my laziness does me favors. Me trying to take the easy way as first step can be laziness, but also advantageous. Here's another one, not laziness, it was necessity............. Needed to know how my TC was acting when actually running the road, but I couldn't see behind me and down over the back of the seat while driving, etc., so...................
Ordered my first (and so far, my only) GoPro type of camera and a precut (scored) pluck & pull hardshell case. Mounted it to the crossbar behind my head, pointing down at the TC. Multiple articulating devices and straps that were included got it pointing correctly, wrist-mounted remote control allowed for turning it on when ready to hit the gas. Adding a link to it for everyone that wants a GoPro, but doesn't want to break the bank.
SINGLE WORD OF CAUTION: Fixed wide-angle lens makes a small picture/view at distance. Variable angle lens would be more versatile.
Campark 4K HD 20MP 1080P Waterproof Sport Action Camera WiFi EIS Video as Go Pro | eBay............$54.
GPCS-S: EVA Hardshell Case for GoPro HD Hero Sport Camera & Accessories | eBay.............$8.
 
Top