400cc Honda CB-1 Track Kart Project Built From Scratch

[Ben_dl]

Hey all! I'm new(ish) to karts and even newer to the forums, but just thought I would post this project somewhere so I could gets some tips and info on kart building as a whole. This project started when I saw a video of this guy's GSXR 750 powered go kart that looked to be made from an extended shifter kart frame and I wanted in. Around Christmas time, I was looking at engines and found a Honda CB-1 engine that some guy was selling for 250$. The engine wasn't perfect, and required new gaskets, cylinder liners, rings, and a valve job but was overall pretty clean from being inside for around 7 years. After that I started doing some research on how to actually build something like this and got to modeling the frame in cad. Once I had all the measurements, I bought some 1 1/4 inch tubing and started the process of bending and welding the frame together. As of now I would say the frame is about 3/4 the way done as I still need to weld in Axle, Steering, Seat, and rear wing mounts (plus a bunch of smaller things like pedals and a shifter) but hopefully I can get it going in the next year or two. If I am doing anything wrong or could make some changes please tell me, the pictures are what I've got so far.

 

[Denny]

I would ditch the wing. Yea, it looks cool, but you don’t need anything else to help that kart fly. You want to keep it on the ground.

 

[Master Hack]

Thiis is my kinda project! Build it go all out!

Nevermind Denny , hes old!

 

[BaconBitRacing]

I agree with Denny, ditch it for now. Lotsa engineering goes into making a wing make downforce, and the way air moves around is important. Example of why aerodynamics is difficult: https://www.racingarchives.org/blogpost/a-truly-secret-test-of-the-porsche-917/

 

[Master Hack]

I agree with Denny, ditch it for now.

Sound like nuther old guy....

 

[Ben_dl]

Yeah I was probably going to save the wing for the later stages of the project just because I don't have as much experience making aero bits as I do with frame and engine bits, but I'm hoping I can figure it out with enough research and get it going with the wing eventually . For now though my focus is just getting the frame done before the cold weather hits.

 

[Master Hack]

I have found that as a project like this nears completion, the unnecessary items get moved to the bottom of the list. The items that are required to achieve operational status receive all the attention. The cosmetic goodies come later.

 

[Ben_dl]

Hey everyone! just wanted to give a quick update. I’ve completed the front end steering and spindle mounts (also got a steering shaft) and I’ve added a diagonal member to the bar just behind where the seat will be. The seat will be here in a few days, and after I’ve finished the mounts for that it’s on to the rear axle.

 

[Ben_dl]

Also I was wondering what size axle I should use? I was thinking on a 40mm axle but I’m not sure what size would best handle the power of the engine.

 

[BaconBitRacing]

Also I was wondering what size axle I should use? I was thinking on a 40mm axle but I’m not sure what size would best handle the power of the engine.

1 inch axle is the standard, it handles lotsa power.

 

[Ben_dl]

1 inch axle is the standard, it handles lotsa power.

Solid steel I would assume?

 

[BaconBitRacing]

Solid steel I would assume?

That is correct. https://www.bmikarts.com/1-Steel-Live-Axle_p_517.html

 

[Ben_dl]

That is correct. https://www.bmikarts.com/1-Steel-Live-Axle_p_517.html

Thanks a ton man! BMI karts has been my savior for this project so far.

 

[BaconBitRacing]

Thanks a ton man! BMI karts has been my savior for this project so far.

No problem. Check around, BMI usually has the cheapest axles but if you need more that just an axle a kit can be cheaper. As always shop around for all your parts!

 

[Ben_dl]

Hey everyone, I know it’s been quite a long time since I’ve posted an update on this project but things have gotten busy. I’ve been able to get a good chunk of stuff done with it though, I got the front spindles and mounting hardware, rear axle and axle bearings/hangers installed, front floor pan mounts (just old tie rod ends lol), a mount for the seat (which is only semi done, it’s the big flat piece behind the steering shaft support) and a very DIY shifter that I’ll weld a shift linkage mount on to later.

 

[Ben_dl]

Small update: pedals!

 

[Denny]

How do you pedal it with those?

 

[Ben_dl]

How do you pedal it with those?

You’re right, need a way to pedal home if the engine blows up.

 

[Denny]

Cool!