Posted by: Mike Torrey TITLE: MOTORIZED BICYCLES: tecumseh tclll motors
I,ve been riding a motorized bike for going on 2 years the 49cc tecumseh tc3 WITH Dimension edge fiction drive system,in that time the has blown a short block 5 times !!evry time but once i was useing the larger drive wheels the exception was a 1" wheel down a hill and i was hauling at 43 mph when it blew.recently i bought a new motor (the same one)and a blew anther short block after less the one month are these motorers any good??? any suggestions to avoid another engine failer would be greatly apreciated help.....please....thanks in advance
Posted by Mike Torrey
thanks john that helps alot but i,d still like to have the requestd eqation ratio so i,ll know which wheelis ideal for certain terrian ete...what wheel is your favorite say for rough rutted backroads??and have yor engine ever been short blocked?if not whats your secret?thanks i just despise the thought of any more down time.
Posted by John Walker
I have been running the dimension edge tecumseh setup for about 5 years now and just about a year ago got a replacement unit with the TCIII engine. I had the engines checked and the top RPM of the old and the new TCIII engine was a little over 6000 rpm. I use a 1.25" diameter roller which causes the rear wheel to turn about 300 times at peak rpm giving a top speed of about 23 mph. If a 1 inch roller is used the top speed at 6000 rpm will be about 18 mph and a 1.5 inch roller will give about 27 mph. I have over revved these engines a little and have no problems but I would not recommend overrevving them more that 500 rpm or so. I have never found it necessary to break the engines in but the oil to gas ratio is critical. The ratio is 1 to 24 meaning that you must completely mix 5.5 oz of oil with a gallon of gas and it has to be the best 2 stroke oil and not regular motor oil. Another critical factor is using this friction drive system is to be sure that there is just enough roller down pressure so as not to cause slippage when using the system. too much down pressure can cause a strain on the lower end of the engine. These engines are no longer available except from one source (dimension edge no longer stocks them) so that is why I got an extra unit but I do use both systems daily. My older engine has about 5,000 miles on it but it still runs good altho it is a little worn and is not as powerful as it used to be. Good Luck
Posted by Mike Torrey
not really man thanks i think i need to troddle back a little what i really need to know i think is the eqation for figure out the exact for a fiction driven set-up with 7000 rpms of the motor on a 26" frame solid i please what size drive (diameter ) wheel will match this combo as to not over power or underpower this engine anyone please>>>
Posted by Esteban
In my opinion, ALL of these small motors need a lengthy break-in period. Have you been doing that ?
Posted by Mike Baldwin
..."are these motors any good"...I think the need for multiple short block assemblys has answered your question. Everyone has a different ideas on what a "blown" motor is. In my book, a engine must suffer catastrophic(sp?) failure to be considered "blown". EG - A broken case with a connecting rod and battered piston hanging out. At the least, you may consider this question. Could you be exceeding the intended design capabilities of a low cost, consumer grade, small engine? - Best Regards , Mike Baldwin
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