Upgrading your moped with a cylinder set is no problem... provided everything is right. If you have had a hot runner or stall, there is a chance that a lot more is broken than just the cylinder or piston. Check the bearing of your crankshaft, especially the one on the ignition side of your engine because you can test it on your bike by feeling if you can move the flywheel vertically while it is stuck in your engine. 

The big-end bearing of the connecting rod in your crankshaft may also be broken. Check vertical play again because this bearing is sure to take a huge hit in a hot run and stall. If your moped block is good you can start looking at the cylinder set you want to order. 

At Tomoshop we have a lot of different sets, from 50cc original to very aggressive 70cc's! For example, take a 50cc Airsal cylinder if you want to be smoother than original with a lightweight aluminium cylinder with nikasil wall. If you go all-in, you can go for the perfect 70cc kit for Tomos: the 70cc Parma kit. What you can or should do with this before fitting it you're going to see in this video!

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Moped maintenance: Tomos cables and switches
Moped maintenance: Tomos cables and switches
Are you having electrical problems on your Tomos? Is your handlebar switch no longer working properly? In this video you'll find tips & tricks on how ...