[Kartbuilding] Go kart Questions

[Stephen Burke]

Hi Austin,

Im glad you found the www.kartbuilding.net website useful, and that you 
have decided to build a kart yourself. It does have a lot of the info needed to build a go-kart of any type. Onto answering your 
questions:

#1. The Throttle on your Honda GC160 engine.
I done some looking there and have found some nice diagrams/info about 
your engine:
- Blueprint for your engine & drive shaft:
http://www.tulsaenginewarehouse.com/catalog/honda/specs/gc160/
- General Info:
http://www.trupower.com/honda/gc160.htm

Actually - here is the User Manual for that Honda GC160 engine!!:
http://www.honda-engines.com/Engines_owners_manuals/ownersmanuals/31Z8A000.pdf

It shows you all you need to know about the throttle.
Does yours have a variable throttle lever? (as on page 2 of above manual?) 
If so - all you have to do is connect up a small cable (e.g. brake cable 
off a bycycle etc. to operate this throttle lever. Bycycle shops will give 
you extra long brake cables and a reel of brake sheething which you can 
cut to length.

If you dont have a throttle lever on your engine, you have to look at the 
carburattor itself. There will be a small lever which links up to the 
"butterfly valve". I couldn't get a clear picture of this valve from the 
above manual. Here is a photo of this lever on a carburattor of mine:
(valve closed - engine idling):
http://www.kartbuilding.net/gallery/v/Kart_Clearance_and_Memories/DSC01242.JPG.html
(valve open - engine turning fast):
http://www.kartbuilding.net/gallery/v/Kart_Clearance_and_Memories/DSC01243.JPG.html

Notice too the screw on the above lever - this is to adjust the idling 
speed. You need to firstly - find this lever on your engine (there should 
be a spring attached to it) (you might have to take off the aircleaner to 
see it fully). Run the engine - turn this lever manually and see if the 
engine speeds up when you pull on the spring. If this works - all you have 
to do then is to connect up a cable to operate this small lever. It should 
work fine.
The reason a throttle lever is not on all engines - is because they dont 
need to go slow/fast - just run at the same speed. But ALL engines can be 
made to go fast/slow by adjusting this throttle adjuster lever connected 
to the butterfly valve which limits the petrol filled air from going into 
the engine.

#2 - Axle Bearings
There are a few types of axle bearings available. As you said - you wont 
really know until you have it in front of you.
The main thing to note: DO NOT DRILL HOLES IN THE CHASSIS <-> this will 
only weaken the chassis causing it to break/bend. WELD ON A LUG or SUPPORT 
BRACKET onto the chassis FIRST - then bolt the bearing housing to this 
LUG/SUPPORT BRACKET.
This picture shows the above -> 
http://www.kartbuilding.net/Freeplans/images/pillowrunner.jpg
(or the page for axles is on 
http://www.kartbuilding.net/Freeplans/axle.htm )

You could also have a Vertical Bearing mounting plate - in which case you 
have to weld a vertical plate to your chassis - and then bolt your axle 
bearing to this instead. See: 
http://www.kartbuilding.net/racingkart/Old_Racing_Kart/rearaxle.htm

Just make sure that the axle rotates freely before welding/bolting the 
axle mountings onto the chassis. ALSO - make sure that the rear axle and 
its wheels are parallel to the front stub axles (i.e. distance from rear 
left wheel to front left is the same distance from rear right to front 
right wheel)- other wise your tyres will wear very fast.

Anyways - if you take any photos send them on and I will put them on the 
www.kartbuilding.net website.

Best of Luck,
Steve

On Fri, 1 Dec 2006, Austin Tsai wrote:
> Hi there,
>
> First off, I'd like to say how wonderful your site is. I recently got into an 
> automotive class in school and thats when I decided to build a go-kart and 
> stopped by your site. Very nice layout, and tonnes of info!
>
> Anyways, I was wondering how I could get my engine to drive by a wire. I know 
> there are throttle kits out there, but I'm not too sure how they hook up. 
> Right now I have a Honda GC160 (Horizontal shaft engine) that I have rebuilt, 
> but the only problem is to get it to drive by a pedal speed. Any ideas on how 
> I can accomplish this?
>
> Second question I have is that I bought an axle bearing kit (It hasnt arrived 
> yet so I might be jumping the gun a little here), and I was wondering how you 
> can attach it? I know the kit comes with the bearings as well as a bracket, 
> so my guess right now is to just weld the bracket onto t he frame, correct? I 
> see a lot of professional go-karts have a different type of axle bearing so I 
> havent been able to find what I want.
>
> Thanks for all your help in advance, keep up the awesome work!
>
> Austin Tsai