Hi!
My son has a '13 Fantic TZ125 which is powered by an EC 125 engine.
As a part of rebuilding the engine, I purchased a Prox conrod kit for the engine.
Handed the new conrod and crank to a specialist shop for replacement and balancing.
Got the crank back, pulled together the engine, fitted piston and cylinder and tried to turn the engine - without success. Turns out that the new conrod hits the crankcase on its way down on the exhaust side, due to a different/ fatter shape around the big end. See attached image.
The original Vesrah conrod has a slimmer shape and the crankcase has a grove on the exhaust side allowing the conrod to clear the crankcase.
After investigating a bit, I found out that I had received a Prox 03.6220 kit, that is listed by Prox as a kit for KTM SX/EXC 125 and Husqvarna TC 125.
Prox does not list any conrod kit for EC 125.
After contacting the store where I bought the conrod, I got the following explanation:
- GasGas has ended cooperation with Vesrah, and are now delivering the Prox 03.6220 kit as conrod kit for the EC 125
- The problem affects only some bikes due to differences in production of crankcases
- The solution is to trim the crankcase allowing the Prox conrod to pass
Has anyone else experienced this? Should I accept this as a solution?
Have tried to search the Internet for any info on this topic without success.
--
Sigurd Ringbakken