Pipes, silencers, carburetors, reeds and valves are all popular bolton modifications. 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. 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. Determine the level of porting you wish to achieve before you start cutting or grinding. Most of the errors is to choose a less appropriate combination of engine components so that the engine actually ran worse than standart, ever experienced. Really cool two stroke cylinder porting software youtube. The morbidelli 125 twin road racer is a rotary valve engine. For port work, one company that will help you is 2strokeporting. The software in addition to defining the geometry of the insert, it also indicates the processing steps for its craft realization.
Enthusiasts, tuners, mechanics, gp, drag racing, mx, enduro. Feb 16, 2017 two stroke cylinder porting tips watch this before you start cutting. I only have a dremel and was wondering if i could do anything at all myself to my yz125 before i put it together. Purchase the porting tools you need at our online store. Kick ass and take names with this baby software located on the web at this address.
Feb 08, 20 well i have been reminded lately that this is a dirtbike forum where i can ask questions so i figured id give it a shot. An engine port is an open window in the cylinder wall for the intake or exhaust of fuel mixture airgas. Crankcase and cylinder porting is probably the most controversial subject among performance 2 stroke engine builders. You should only rely on the experience of the very best. Two stroke engine porting zmod this software made for help out team in first time, but some friend advise this is the time to share.
Bimotion 2 stroke software has been commercially available and in professional use since 1991. Show flow efficiency by rpm help you modify port better before action. Each intake port can be locked to a fixed timing relation with the exhaust port. The best thing about bolton modifications is if you dont like what the product. Porting and polishing twostroke motorcycle engines.
Bigger carburetors, higher compression ratios, altered port timings and expansion. Hi performance two stroke porting software program youtube. We now have a simple 2 stroke expansion chamber design program. These modifications can be extremely effective when used in the right combinations. Mota for windows slide show of features millions of tuning variations possible. Finally, enter the exhaust duration of 184deg and the peak power speed of 12500 revsmin and click the design now button. Time between exhaust port opening and transfer ports opening. If you are aiming for these qualities, modifying your 2stroke engine is a great. Mota software, 2 stroke engine simulation software, 2 stroke exhaust design. Porting and polishing two stroke motorcycle engines. The newest info i have is the two stroke tuners handbook by gordon jennings.
Softengine engine simulation software production 2tbase seven software. Jul 18, 2017 porting and polishing two stroke motorcycle engines. Two stroke cylinder porting tips watch this before you start cutting. The following are spreadsheets for different aspects of 2 stroke designmodification. Next enter the cylinder bore and stroke which are 40. Sep 30, 2012 kick ass and take names with this baby software located on the web at this address. But because of the limited worldwide activity in two stroke engine development, program sales were limited and further development was curtailed.
This kit is one of the best options for doing mx and dirt bikes of the 100cc, 80cc, 70cc, 50cc, and even down to 30cc, 2 stroke variety. However, you shouldnt just pick any business that you can find anywhere. Apr 08, 2007 im looking to start doing all my own porting and was thinking about buying the tsr 2 stroe porting software, has anyone used it, and is there any better software out there. The inlet port opens 30 after bdc and closes 79 after tdc. All engine development is done exclusively with tsr two stroke racing engine design software and. Heres how shaving off miniscule ammounts of metal can drastically improve your speed. Port matching, porting and trenching twostroke engine cases. The software does complete cycle simulation of the whole internal combustion process including the gasdynamics in the pipesducts, ports and plenums air boxes, boost bottles, exhaust boxes etc. You should read about how the two stroke enigne works before you attempt this. 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. Apr, 2015 has any one done any kind of porting or polishing to a 2 stroke cylinder themselves. Developed by pedro, with more than 20 000 lines of code, all the knowhow applied to software comes from us and also a lot from the legendary portuguese 2 stroke tuner lufo racing, this software is directed for all 2 stroke. If you are aiming for these qualities, modifying your 2stroke engine is a great strategy. The other is how air density barometric pressure, temp, humidity, and elevation change, affects horsepower.
Many things will affect the power delivery of two stroke motorcycle engines. Each part of the 2stroke cycle can be evaluated and designed with computer software. Jun 24, 2007 i was reading a thread about a 2 stroke versus a 4 stroke and it occurred to me that if the porting, or timing, of a 2 stroke could be changed, that maybe its maximum torque range could be lowered to an rpm comparable to the 4 stroke, and thus swing the same prop as the 4 stroke. New version of 2t exhaust calculator it is a freeware 2 stroke expansion chamber exhaust calculator program download at. Purchase with immediate download from digital river, shareit. This program is not a part of mota, but it has been put together. Specialty tools for porting 2 stroke, 4 stroke, cylinders, cylinder heads, 2 stroke case porting, and intakes. Two stroke engine and exhaust design software north. 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. If you are aiming for these qualities, modifying your 2 stroke engine is a great strategy. Calculate the needed exhaust and transfer port durations to match the. Two stroke engine porting zmod for android apk download.
Those of us who have grown up in the japanese two stroke. Port heights port durations required ranges of port mean areas possible ring flutter rpm mean piston speed suggests carburettor size power meter you input expected bmep value adjust port shapes for target areas in cad window. This can easily ruin your eninge, but can also increase performance by alot. These are the files that can function manually without using macros by using open office. Oct 04, 2011 changing the power of 2 stroke engine is really very simple when you know the basic techniques of 2 stroke engines.
The website does not intend to compeed with any other website dealing with 2 stroke tuning, and the information shared is not at all as thorough as what you can get from reading the books. We also have a simple 2 stroke expansion chamber design program. From beginners in porting,to brazen speed phreaks, this is a great tool if your not a molecular, thermohydrus calculus genius space physicist math scientist. 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.
Software for fine tuning and design of two stroke engine by. This expansion chamber is not the product of simple correlations as for other products that abound on the web, but an automatic design created by mota which is a full wave action 2 stroke engine simulator. Softengine engine simulation software 2tbase seven software. The piston crown opens and closes the exhaust and transfer ports. Ask our shadetree mechanics 2 stroke wizard pipe builder. Contents chapter 1 introduction 9 chapter 2 the cylinder. Im working on gathering enough parts to build a triple cylinder rd400 and at some point ill need to sort out the porting and exhaust. There is one or more forwardlocated exhaust ports, two or more side transfer ports, and one rear intake port.
Note that you do not require a paypal account as you can use your credit card. Twostroke waveaction engine simulation motion software. The official home page of the 2 stroke wizard tuned pipe 4t exhaust header wizard software. How to tips from tj on porting and polishing 2 strokes. Simple twostroke cylinder porting tutorial youtube. This will get you started by providing, for your engine, the dimensions of an expansion chamber with a 2 stage or 3stage diffuser. My name is ed erlenbach, im a private tuner specializing in yamaha rd and tz performance in southern california. Fink is open source distribution software specifically designed for porting applications in mac os x.
881 230 559 1281 847 872 1005 1114 402 525 605 611 510 959 1337 1531 1218 126 851 966 246 1071 1205 201 621 1276 1408 96 821 726 450 1163 1179 1134 339 1362 1268 695 253 723 160 334 1312 978 586