Two Stroke Racelab

  Two Stroke Exhaust Systems by Roy Bacon (Lodgemark Press, England, late '60s).

Handmade exhausts for Honda RS125 NF4 (1990 - 1994) models, are now available via my  online store. This pipe will fit 1987 - 1989 models ONLY if a 1990-1994 cylinder is used as the exhaust flange is different on earlier models.  Later 1995-1997 cylinders can be used as well and will work great with this pipe.  The package includes :  an expansion chamber a suitable exhaust flange 2 X exhaust springs (same dimensions as OEM) An end can is not included but the stock one can be used or even better a later NX4 type as the rear mounting point for the end can is not used.  For more pictures of the expansion chamber, check out the below link.  Handmade Exhausts Price is 220 Euro (worldwide posting costs included).  Prior buying the pipe, please contact  for estimated delivery time. 

Many thanks to Trev(OZ) for sharing a couple pics from one of his latest 125 rebuilds. It's always very encouraging & flattering seeing some of my work been used on an actual bike. Thank you all for your support, it's a great push to keep me trying to get better.

Many thanks to Mikkel(DNK) for sharing a photo of his lovely NF4 bike. I hope it will be ready soon and the new pipe will deliver the goods.

Walter (AUT) at Classic-Bike race in Schwanenstadt, Austria on September 6th/7th.  Freddie Spencer attended this race. So, here are some bonus pics on a VFR750R.

Many thanks to Walter(AUT) for the pics of his NF4 bike. I hope the new pipe will deliver the goods.

I'm in the middle of fabricating an expansion chamber for my Vespa smallframe. It's a demanding job with lots of challenges but I hope that eventually everything will go well. It seems like I will have to spend a lot of working hours along with my tig welding machine.

Frits Overmars is a well known tuner and very knowledgeable on Aprilia 2T racing bikes. The below schematic with calculations, offers his point of view with a simplified exhaust concept that will give some basic exhaust dimensions to start working on.

...to Rob (OZ) for the photos of his NF4 bike. I hope the new pipe will deliver the goods.

Packaging expansion chambers for Stephen(CA) and repairing some PGM units for Nick(GR). Still need to clean up a Cagiva Mito cylinder for Beez(GR) but I can't find the bottle with the muriatic acid. However, as a philosopher professor once said ...there's always room for a couple beers! 

First one ready, 6 more to go... one more for Robert(AU).

I've made some improvements on the exhaust flanges for the NF4 expansion chambers. New units will incorporate the mounting points for the exhaust springs. They look lovely, can't wait to try them out. 

The forthcoming weeks will be quite difficult with some serious sheet metal forming and lots of tig welding... as I have to manufacture five Rs125 expansion chambers for Stephen(CA) and another one for James(OZ). Most probably, more pics are coming soon... Cheers!

I'm currently building an expansion chamber for a friend. His TZM now features a YZ85 engine hence the need for a new expansion chamber that fits the bike.

This is a Modenas Dinamik, it is based on a moped called "Leostar" by Kawasaki and it's a little bit more popular on the Asian market.