Other books to his credit are modern engine tuning, two stroke performance tuning and forced induction performance tuning. First rule of 2 stroke or any tuning is to make it like it should be, i. An excellent academic book on the theory behind performance tuning for 2stroke motorcycles. They are so simple and fun that ive always enjoyed tinkering with them. The way a two stroke motor works causes them to be f. Reviewed in the united states on november 20, 2014. Balancing the crank dynamically, getting correct piston to bore clearance, using good rings with correct end gap, matching piston weights. Aprilia two stroke champions have included valentino rossi while australias casey stoner won many gps on aprilia two stroke machines. Aprilia rs125 race parts, for track or street, carbon parts, cnc, cylinder inserts, silencers, exhausts.
The morbidelli 125 twin road racer is a rotary valve engine. His port time equations dont even include rpm, you input the dime. Geared specifically for gp and kart racers, this hardcover treasure has turned out to be a great reference source for questions on the logic and concepts that pertain to tuning a 2stroke for maximum performance. A range of tuning and performance parts for the aprilia rs125. Part of the mystique of two stroke racing included the black art of tuning the engines. Aprilia rs 124 keeps twostrokes alive car news carsguide.
It seems almost fitting that this is the last week of testing for motogp before the winter ban sets in, and also that we discover that three aprilia rsw 500s 500cc 2stroke gp bikes are up. Finetuning of a two stoke engine in full power configuration. The rs4 125 is a four stroke variant of the extremely popular rs125 two stroke race replica. Jul 16, 2009 aprilia carries on the production of their latest supermoto and enduro 125cc models, the sx 125 and rx 125, in 2009. The aprilia rs125 is a gp derived replica sport production motorcycle. Bigger carburetors, higher compression ratios, altered port timings and expansion. The bike is based on the four stroke version of the derbi gpr125. To learn more it is best to buy a 2stroke tuning book. Customizationoptions including bodywork, suspension tuning and. I have had this for just over two years and it is an incredible bike to learn on perfect size to bridge the gap if you are looking to move onto a bigger bike, or great as a commuter. First ever ride out on the road and first time out on my new aprilia rs 125. Many thanks to everyone that bought the book and i hope.
On a stroker things like matching the ports to the liner, crankcase to transfers etc. Two stroke performance tuning a disc partially cut away and attached to the end of the crankshaft opens and closes an inlet port in the side of the crankcase. The aprilia rs4 125 is a 125cc class sportbike manufactured by italian motorcycle firm aprilia. Other books to his credit are modern engine tuning, twostroke. After really good sales of my autobiography the mechanic who got lucky, i have completely sold out.
Graham bell is an acknowledged expert on engine tuning, with many years experience in this field. This racing experience has been used by aprilia to. Two stroke cylinder porting tips watch this before you. Nov 26, 2008 it seems almost fitting that this is the last week of testing for motogp before the winter ban sets in, and also that we discover that three aprilia rsw 500s 500cc 2stroke gp bikes are up. Pjme motorcycle engineers, 2 stroke engine specialist aprilia cagiva. Graham bell starts off by saying that he doesnt believe port time area and its all about the duration the ports are open. Oct 15, 2008 tss rs500 2 cylinder 2 stroke by paul crowe while most everyone else has moved on to the land of 4 strokes, theres a group of intrepid engineers and builders in australia devoted to the idea of building a 500cc 2 cylinder 2 stroke motorcycle, starting with the aprilia rs250 chassis and installing their own highly engineered 2 stroke powerplant. In motocross its usually a compromise between best peak hp and good early off the pipe power. Ill try and get the ball rolling in here with a list of books i currently own on 2 stroke engines, and 2 stroke engine performance tuning. Those of us who have grown up in the japanese two stroke. Floydy racing two stroke tuning john floyd home facebook. Race steps for your aprilia rs250 are available in our tyga shop.
Tips on how to port a two stroke cylinder, what to donot do and how to do it right. Will be fully gone through by ex gp rider and top 2 stroke technician with over 30 year experience. In the present paper, the authors show the finetuning of a 2s engine in full power. When the ignition switch is turned the actuator slowly turns until it reaches the full close position. The aprilia rs250 is a sport motorcycle that was produced by the italian manufacturer aprilia between 1995 and 2004. Aprilia parts are pricey and take a while to come so once again youll be off the road. Floydy racing two stroke tuning john floyd hastings, east sussex rated. I didnt really like many of the pipes but a few were ok but i wanted more. Two stroke combustion chamber shape design basically consists of two parts. Get it if you want to squeeze peak performance out of your 2 stroke engine. Two stroke tuners handbook 2 another mistake commonly made, sometimes even by those who have enjoyed some success in modifying two stroke engines, is to believe in a kind of mechanistic magic. Instagram motomaxuk camera drift ghost with drift external mic.
Contents chapter 1 introduction 9 chapter 2 the cylinder. Two stroke cylinder head design don terrills speedtalk. The main drawbacks of two stroke 2s engines consist in poor engine efficiency and high level of pollutant emissions. Graham bells two stroke performance tuning is the book to have. During the last 20 years twostrokes have practically vanished from the streets. Aprilia has had many grand prix victories in the 125 cc and 250 cc two stroke classes. See 4 results for aprilia rs 125 2 stroke for sale at the best prices, with the cheapest ad starting from. Twostrokes have always been for the true enthusiasts who loved tinkering and getting messy, says pecora.
This two stroke stink wheel has been terrorizing the streets ever since it first coughed its way into life in 1992, replacing the equally polluting. Roadgoing bikes have practicallydisappeared, with the exception of the 50 cc aprilia rs4. See 5 results for aprilia 2 stroke for sale at the best prices, with the cheapest ad starting from r 6 000. Aprilia rs 125 2 stroke for sale april 2020 newsnow. See 35 results for aprilia 2 stroke for sale at the best prices, with the cheapest ad starting from. Sure, a few niggles may come up but its a bloody 2 stroke, it cant be rocket science. Our specialist engine tuners will be able to help you with every aspect of your tuning and servicing. I know theres probably lots of info on the internet, but i want a book i can carry around with me and randomly read a section or two when i get to the straighter sections of i5. The inlet port opens 30 after bdc and closes 79 after tdc. I have been into 2 stroke bikes for over 28yrs and i have bought and tested many exhaust pipes on all the bikes i have owned to find the best one for my needs. Selling this 2016 66 plate aprilia rs4 125 with only 1765 miles. Buy aprilia rs50 rs 50 cc 2 stroke 6 sigma custom carburetor carb stage 17 jet kit. Suzuki rgv250, aprilia rs250 tuning and blueprinting.
Nov 11, 2010 jennings book talks about port time area and porting the cylinder to have peak efficiency at a certain rpm. There are many ways to boost the power, one of which is by installing a tuned pipe. Currently not new in the lineup, but radically improved, the models announced a. Tyga performance race steps for your aprilia rs250, cnc made and all parts are replaceable, aluminium light weight. The high performance two stroke engine by john dixon is also very good. Jenning vs graham bell, 2 stroke tunning books motorcycle. If you are stuck on a 125cc bike for a year or two, you might as well have the one that offers the most fun, and that means the legendary aprilia rs125. Fastline superbikes are pleased to offer this lovely all round aprilia rs250 mkii aprilia racing replica 1999 model. Stan stephens tuning are the uks number 1 two stroke tuning firm. Two stroke tuners handbook 2 another mistake commonly made, sometimes even by those who have enjoyed some success in modifying twostroke engines, is to believe in a kind of mechanistic magic. Other books to his credit are modern engine tuning, twostroke performance tuning and forced induction performance tuning.
The piston crown opens and closes the exhaust and transfer ports. Changes in squish velocity require changes in the ignition retard curve. Jun 28, 2014 first ever ride out on the road and first time out on my new aprilia rs 125. Everyday low prices and free delivery on eligible orders. The old adage of stuffing cases on every project just isnt true any more. Full 2 stroke rebuild time lapse 2007 yamaha yz125 win this dirt bike. I wasnt lucky enough to grow up around them 2stroke smoking machines, so i dont get all misty eyed like some of my fellow rsbfs contributors whenever a suzuki rgv, honda nsr250, or aprilia rs250 comes up for sale. Ten motorcycles that remind us why we miss twostrokes new atlas. The trend in high performance two strokes has continued towards more case volume, however each engine and application differ. The cost of running an aprilia rs 125 2 stroke duration. Jennings book talks about port time area and porting the cylinder to have peak efficiency at a certain rpm. Aprilia rs50 rs 50 cc 2 stroke 6 sigma custom carburetor carb. Aprilia has a long and storied history of producing highperformance racing motorcycles, having taken the inspiration for the rs250 from the aprilia rsw250 grand prix, a motorcycle often used by legendary racers in motogp events. Two stroke performance tuning chapter 3 porting and cylinder scavenging today, when we take a look down the cylinder of a two stroke engine, we find its walls literally filled with ports to handle the induction, transfer and exhaust phases of gas flow through the engine.