I picked up an exhaust pipe for a GX1160/GX200 off Marketplace over the weekend, which I will be fitting to my CK.
I have ordered a Stage 1 engine from GX tuning, but this comes with a de-baffled OEM exhaust, however I want a system that will pass the exhaust out through the body-side.
I will need a silencer to go on the end of the pipe, but was concerned with allowable noise levels, and wondered what noise restrictions various venue have?

I came across the following figures for GX200's on the internet:

EXHAUST TYPE   db@idle    db@ 4,000 rpm
OEM                       85             98
debaffled OEM         87            100
Pipe & silencer        92.5         104.5
Open pipe              100.5       111

I was looking to fit a RLV high flow muffler or RLV high flow muffler with additional baffles as sold by GX Tuning, but would like to hear (no pun intended) what others have found successful?  I would also consider making my own absorbtion type silencer as the pipe and silencer at 104.5 seems quite loud to me.

Hi all,

I thought it was about time I properly introduced myself and started my build blog.

My name is Ian, but most people from the RAF or motor racing know me as Billy (long story).  I'm in my mid 60s and was in the RAF as an aircraft technician for 35 years, then a project manager and engineer restoring warbirds (Hurricane and 2 Spitfires, and now work as a logistics and maintenance engineer.

In my spare time I like anything vehicle orientated and have built a couple of kit cars and designed and built my own racing cars.  I was the Competition Secretary for the RAF Motor Sports Association for many years and managed a Sprint track, a Speed championship and a Racing championship.  I think you guys have a fantastic thing going on here and I would gladly assist wherever possible (I have various safety cases, regulations, forms etc that can be easily adapted to your use and would be willing to share these with you).

Anyhow enough blabbing on about myself, so I have attached a PDF of where I am with my Cyclekart.
 
Also many thanks for all the info people have posted on the forum and the many informed answers I have received to my queries 


 

Hi all,  I have come up with a bit of a stopper on my Cyclekart (promise to start a build-blog as soon as I have some spare time).  I want to use a 35 chain but struggling to find suitable driven sprockets (about 75T to 80T).  I have found some in Australia but postage is £58!!!!!!  Does anyone know where I can get some in the UK?

Hi guys, a couple of weeks ago I decided to make a tadpole three wheeler Cyclekart, and was looking to do a BSA.  However, Chris had done one of those so then found another to do, but the shortest i could get the wheelbase was 72" and that would make the body too long for transporting.

Consequently, I decided to build a four-wheeler as the engine would sit between the wheels and enable a shorter wheelbase.  After a lot of searching decided on an Austin 7 Twin Cam for many reasons and whilst searching for info found out someone is already doing one of those.  Anyhow, I am too far along the road to change again so will press ahead with another Austin 7 Twin Cam.

Anyhow, the build table has been cleared of all the junk, the plan laid out and the chassis is now half complete.  I've designed and built a variety of race cars, but a "simple" Cyclekart has thrown up all sorts of issues, so would like to consult the more experienced and see if the following aspects will be a problem:

• The chassis/body will be a tubular frame with ally skins (cos theres lot of ally and tube in my workshop left over from previous projects).
  
  The rear will be conventional solid mounted kart axle and double driven wheels, but the front will have equal-length, parallel, double wishbones as this can easily replicate the inspiration cars fairly straight tube axle and transverse leaf-spring with diagonal radius arms.  It will use Gemini coilovers which will be hidden inside the body and operate via the upper wishbones, which will be rocker arms.
  
  i have spent all afternoon looking at 17" wheels, which is being a problem, then saw some are using 14" wheels and they come very close to the 75% scale size of the originals.  So if i use 14 wheels and wider tyres this will look more like the wheel/tyres of the inspiration car.  An added bonus is it also negates the problem I was having sourcing the rear sprocket and packaging of the sprocket in the available space.  Plus the wheels and tyres are cheaper, plus it improves braking as well.
  
  The scale I am using means the wheelbase will be approximately 63", but this may move to 64/65" if the rear axle has to move back to get the engine in.  Subsequently, it is unlikely to be 66".

I have compiled my shopping list (thanks for all the info on the forum), and I am now ready to go and buy the wheels from Fun-Bikes and other parts from Gemini (thankfully only about 25 miles from me).  So, before I go ahead is any of the above diversions from the Stevenson Formula an issue?