The software in addition to defining the geometry of the insert, it also indicates the processing steps for its craft realization. Two stroke engine porting, head mods and pipes two stroke tuning advice from the experts at bimotion. Eric is well trained in the use of the latest software programs that the. Our 4 combo drops on stock cases and makes stupid power. The atk 406 was for many years considered one of the best all around big bore 2 strokes. The old adage of stuffing cases on every project just isnt true any more. I have been dreaming of proper big bore 2 stroke for 8 years now and i even attempted to build my own and it works pretty well. Although there is really no shortage of books on the subject of 2 stroke tuning and preparation, i knew that an active software programme would be able to offer so much more. Cleaning and disassembly inspection and measurement overboring porting replating with nickel siliconcarbide composite plating diamond honing head mods powervalve service piston, gasket kits, and top end needle bearing. If you are aiming for these qualities, modifying your 2stroke engine is a great. First rule of 2 stroke or any tuning is to make it like it should be, i.
Basic 2 stroke tuning by eric gorr changing the power band of your dirt bike engine is simple when you know the basics. We sat down with one of the creators of the brc500 built right here in our hometown of calgary, albert, canada. An introduction to tuning 2 stroke motorcycles for those who want results straight out of the box. Ktm is bringing back the 2 stroke big bore for 2016 moto. The larger the bore and stroke, the bigger the displacement and thus a more power engine an engines bore and stroke are generally chosen to keep the piston speed to a reasonable level around 20ms maximum for a road car, while race engines can generally sustain 27ms or so. We use computer design software to maximize power and torque at any elevation. The big bore 2 smoker thread page 2 adventure rider. Racingsm software 2stroke exhaust calculator lufo youtube. Racingsm software has features for many different areas 2 stroke exhausts development, drag racing features, simulators, carburetor tuning, connectingrod analysis etc with all this knowhow along with lufo racing heritage, we believe this is a very fair price. Those of us who have grown up in the japanese two stroke. We offer trackside testing for both engine tuning and efi mapping, as well as suspension tuning and valving. With a long stroke, there is at any given displacement a reduction in bore, and with it a loss of piston area against which gas. We do have a wide range of big bore kits, including for 2stroke off road motorcycles, 4stroke off road motorcycles, 2stroke atvs, and 4stroke atvs. This section describes the basic function and the most important processes in the 2stroke cycle a tuner need to consider in general and with the bimotion tuning software in particular.
I cant imagine what its like to ride that 760 maico, i have ridden alot of big bore 2 stroke dirt bikes, love that pull the pin and get back feeling when you open the throttle, but cant wrap my mind around 760ccs its gotta be like riding a stick of dynamite. About the same price ranges for the motorcycle big bore kits and the atv big bore kits can be found for the suzuki and the yamaha models. For model applications check the big bore masterlist all packages include. Our yz144 has pushed the amount of power thought possible out of a yz125. Great tool for those who are building exquisite format exhausts, one of the largest benefits of this module is that it can be used with any exhaust formula results. May 27, 2016 so, obviously no one has been one this post for a long ass time. They are so simple and fun that ive always enjoyed tinkering with them. The bore and stroke of the engine decides the displacement of the engine. For port work, one company that will help you is 2strokeporting.
Split your calculated 2stroke exhaust up to 42 sections with regular length or even more with irregular lengths. Basic 2 stroke tuning by eric gorr changing the power band of your. You should only rely on the experience of the very best. Our goal is to achieve the biggest power gains as possible, while maintaining reliability on your 2 stroke engine. We use porting tools that work, and with such a vast experience in this very delicate and demanding area we can usually provide a job that is the equal of anything from across.
A myriad of different aftermarket accessories is available for you to custom tune your bike to better suit your needs. Eric gorr racing offers allinclusive porting packages for all types of 2stroke and. What is the best big bore 2 stroke what motorcycle should i. In motocross its usually a compromise between best peak hp and good early off the pipe power. On a stroker things like matching the ports to the liner, crankcase to transfers etc. I think ktm is bringing back the big bore 2 stroke. The trend in high performance two strokes has continued towards more case volume, however each engine and application differ. A tuned pipe has a set of cones divergent meaning the cone gets bigger. Oct 24, 2017 10 ways to gain power in a 2 stroke engine for free. What is the best big bore 2 stroke what motorcycle.
A big bore kit is an easy way to achieve more displacement, and if you can install it without rebalancing flywheels or boring the crankcases, thats about as easy as it gets. The official home page of our 2 stroke wizard tuned pipe. Computer design software is used to calculate the msv for head designs. A worked example is provided for my old yamaha rz350 29k, 1985, which is almost identical to he yamaha rd350ypvs lcii 31k. Fundamentals 7 pressure can exert its force, that exactly balances the loss of leverage in a shortstroke engine which is, in turn, compensated by a gain in piston area. Ecu, cdi, tuning specialist the modern race bike requires precise tuning, knowledge, and expertise to unlock all possible power, ride characteristics, and delivery of power. When you want real performance gains it is very simple. The way a two stroke motor works causes them to be f. It is also very good for expansion chamber designs.
New feature of racingsm software, the 2stroke exhaust segment splitter. However, you shouldnt just pick any business that you can find anywhere. Found this on the internet so i throught id show all you people who have 2 strokes basic two stroke tuning by eric gorr changing the power band of your dirt bike engine is simple when you know the basics. 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. Imo, theres way more to be gained from the big bore than an slp setup, ive never seen one of those packages impress me around here on the ho motor, but you cant miss what a 925 or similar does. Crankcase porting big bore head design tuned pipe design.
Big bore and supermini packages our big bores, strokers, and superminis offer unrivaled performance. Twostroke waveaction engine simulation motion software. This kit must be used with 41 2 stroke flywheels resulting in 1 displacement. Specificaly written for gokarts engines, but will do any 2 stroke. The one i have been using is call mota, from ian williams tuning. I beams, diamond flat top pistons with 4v reliefs, file fit steal rings, upgraded wristpins, pretty aggressive comp cams and topping it with a tvs 2. Petals reed valve in the 2 stroke engine with reed valve admission, the identification of petals more adapted to the reed valve and to the engine is essential to maximize the performance starting from the intake phase. This software packages may also be available on the internet as the first book is quite old. Although it may have an nc50 designation, it is far away from an nc45nc30, so if you are looking for nc30 info, this isnt the best place for you. Hp is a full on specialist in ecu tuning 2 and 4 stroke, cdi development for 2 strokes, and general mapping needs.
For port work, one company that will help you is 2stroke porting. Careful care must be taken to assure that engine will not end up making less power then it did before the engine porting was done. Bigger carburetors, higher compression ratios, altered port timings and expansion. Plus its air cooled, so that eliminates a bunch of possible problems that any old bike could have ie bent or leaking radiators, leaking water pump. But because of the limited worldwide activity in two stroke engine development, program sales were limited and further development was curtailed. Goofit 44mm big bore 53cc 54cc top end kit for 2 stroke 47cc 49cc engine mini quad pocket bike. Software for fine tuning and design of two stroke engine by. If you are aiming for these qualities, modifying your 2 stroke engine is a great strategy. There are a few software programs available for 2 stroke simulations. If you are racing thr 125 in schoolby 2, local racing, or just want a killer big bore without case mods, this combo is insane. Support racingsm by subscribing our youtube channel. The procedures used to evaluate this engine can be applied to any 2 stroke engine you wish to evaluate. Two stroke modificatons and services four stroke modifications and services suspension.
This page is a long overdue account of my experience tuning the honda express range of mopeds. World exclusive brc racing 500cc 2 stroke the big bore. Balancing the crank dynamically, getting correct piston to bore clearance, using good rings with correct end gap, matching piston weights. If you are aiming for these qualities, modifying your 2stroke engine is a great strategy. Rebuild kits free delivery possible on eligible purchases. There are many ways to boost the power, one of which is by installing a tuned pipe.