10 replies to this topic

[Harrison541]

I've got plans to build my own go-kart, but a few questions first

 

Would 30mm square box section 3mm thick be suitable to build the main frame from?

 

Where is the best place to get a fixed gear 125cc 2 stroke kart engine roughly producing 20-25hp?

 

I know there is a few rotax max engines on eBay, and they fit the criteria, but is there a cheaper option as I'm not planning on racing it professionally, so I dont need the engine to be to an exact specification?

 

Any help is appreciated

Cheers

[cal844]

Why not buy a 125 bike engine? Will be more than enough!!

[Stiggytoo]

Are you planning on using it at a track? They might not like the idea of you using a home made kart. 

 

You should definitely look into IAME Parilla Reedster engines and similar. They are basically the European equivalent of the Rotax engines. 125cc, electric start, centrifugal clutch etc. I say equivalent but they are much better. They are/were used in classes ranging from KF1 to KF4. My one (a KF1) has over 40hp which at one point was more than my mini had!! 

It revs to 16000rpm.

 

Saying that, I've always loved my old air cooled 100cc JICA engine. I used this for 2 years straight without any problems. Very reliable and lightweight. Revved to near 18000! Uses a handheld starter (about £100) The engine can be picked up for about £150 last time I checked. This would be a lot easier to fit, as there is no need for radiators, looms and batteries etc. 

Edited by Stiggytoo, 14 April 2014 - 07:49 PM.

[Stiggytoo]

Also, your best bet is to check eBay.

But this site is great for this kind of thing. http://www.karting.co.uk/MP/

[cradley-heathen]

i have always fancied doing this, but with something like a CBR engine in it.

 

i know it would be nice to build one from scratch, but are you not tempted to buy a chassis and adapt it?

 

as regards the material your talking about making it from, i wouldnt use box as it looks really ugly, tube looks much nicer and is far more professional. as for the guage of steel you want to use, it depends on the design of the chassis. a basic "ladder" chassis would require a thicker gauge, but if you made an intricate chassis, like a minature westfield chassis for example, the triangulation and bracing will make it strong without needing thick walled tubes.

 

if the kart were to be scruitinised at all, its a case of if it looks right it probably is right, if you present someone with a kart made of handy angle with pigeon poo welds, its far more likely to get picked apart.

[megamini_jb]

Also, your best bet is to check eBay.
But this site is great for this kind of thing. http://www.karting.co.uk/MP/

Ahhhh I remember going through uk karting marketplace every night when I used to race.

[Stiggytoo]

Just a bit of random information... Most 2 stroke kart engines use a 219 pitch chain. If you do decide to make it out of tube, adult karts use 30mm or more commonly 32mm tubing for the main structure. Again, if you want to use a standard engine mount, the tubes will need to be 90mm apart if I remember correctly.   It's also worth noting that the chassis needs to flex if you are to successfully make it round a corner with a go kart rear axle.

Edited by Stiggytoo, 14 April 2014 - 09:18 PM.

[M J W J]

There is a haynes manual on how to build a buggy. That might be something to have a look at.

 

In answer to the original question. 30 x 30 x 3mm box will probably be a bit over kill. I built my vauxhall conversion frame from this and have since realised it is a bit over the top. All speed frames are made from 25 x 25 box section. A locost chassis is made from 25 x 25 x 16 SWG box steel.

[xrocketengineer]

Here is some inspiration on go-kart building. At least some fun watching.......

 

http://www.youtube.c...YmklIx5Q#t=1205

[Seba5tian]

Current karts currently use 28 - 32mm tubing for flex reasons rather than "can it hold the weight" so you'll be fine with 30.
If you know a thing or two about engines then a 2 stroke ICA engine or 115cc TKM motor is probably what you're after, but they only produce 20 and 13HP. Apart from splitting/realigning/pressing the crank, boring and honing the barrel, you can rebuild it yourself easily, only tricky(if you've never done it or don't have the tools) bit is setting the timing/ignition etc. If you're not engine/carb savvie you're going to have a lot on your hands as they require constant maintenance and tweaking.  I've never had experience taking a Rotax engine apart (26HP, not fixed geared) but they're water-cooled and have a lot more things to go wrong.

Edited by Seba5tian, 15 April 2014 - 11:41 PM.

[Mini Manannán]

Nicki Lauda was once asked what the difference was between a Kart and a go kart, "100 mph" he replied    Sorry, bit random