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Message: [QUOTE="RM_guy, post: 1424959, member: 20652"] Wow, where do I start? I’m a bit confused. You said there are no valves, etc but the previous owner “bodged” the repair and the valves weren’t fully opening. So are they there or not? If they are there and they aren’t opening (move upward) you won’t have any top end power. If they are not there at all it will be hard to start and you will have no bottom end…only top end. Bottom line is that you have to fix it right and avoid bodgeing it ;) Here’s a link to an exploded view of the power valve and governor. [url]http://www.bikebandit.com/1990-suzuki-rm125-rm125l/o/m147885#sch278139[/url] The compression issue could be because the cylinder is worn. Someone probably changed the piston and rings but never checked the wear on the cylinder wall. Check the ring end gap. It should be around .012”. A bike that old could very well have a very worn cylinder and if the ring gap is large it could be an indication of wear and you’ll need to have it measured. You can also look for wear through the plating. I’m assuming the cylinder has the original plating but it could be sleeved but the wear problem would be the same. You can tell it it’s sleeved if a magnet sticks to it. A sleeve can be bored out if it hasn’t already been bored past its limit, if so it will need a new sleeve. If it is plated, I’d advise getting it re-plated although it might be a bit pricey in the UK. [/QUOTE]