snailspeed

for future reference: honda mt/mb and first model mtx cylinders, heads and crankshafts do not fit. The clutch and gearbox does but the gear ratio's are off so they are not useful. the 50cc engines/engine parts that do fit: MBX50 air cooled AC03, MTX50 2nd model air cooled AD09 MBX50 water cooled AC04 MTX50R water cooled AD06 NSR50 water cooled AC08 CRM50 liquid cooled you can also fit 80cc engines: MBX80 liquid cooled HC04 MTX80r liquid cooled HD08 MTX80R2 liquid cooled HD09 NSR75 liquid cooled DC03 NS-1 75 liquid cooled CRM 75 liquid cooled CRM 80 liquid cooled. for the 50cc engines above there are several 63/65cc (marketed as 70cc) big bore kits available, both taiwanese/chinese and better quality like Malossi. for the 80cc engines above there are several kits available from 80 up to 100cc (often marketed as 110cc) from for example Athena and Gilardoni. Gilardoni also makes a 44 stroke crankshaft to be used with their big bore kit. The standard TLM 50 engine can be converted to watercooled by installing the clutchcover with built in waterpump, from any one of the watercooled models mentioned above. Then it is just a matter of swapping the aircooled cilinder and head for those of a watercooled version.Do pay attention to the fact there are 2 diameters of kickstarter axles used, so make sure to get the right one. VHM makes a CNC head for the watercooled 50cc and 80 cc models, so you can use custom inserts and have them made to your own specifications. When installing any other cilinder than the stock one on the TLM50 be aware that there is a huge variation of port durations between all different cilinders. They range from 1.4kw @ 5000 rpm up to 5.8kw@ 10.000 rpm depending on model and country it was made for so most won't be suitable for any trial work because the torque is either lower than TLM 50 spec, or at a way to high rpm. The easiest way to get way more torque and power than the stock TLM50 is to get a used 80cc watercooled engine, use a german GE3G cylinder (this has the lowest port timing), 18mm manifold and a genuine HM183 18mm carburettor (not a chinese copy). take out the gearbox, and install your TLM50 gearbox instead.

Hi, is there anyone here who has a TLM50 and could measure the port durations for me? what i need is the distance from the top of the exhaust port and transfer ports to the top of the cilinder. thanks in advance.