need help, engine and acceleration issues

[jsnelson1247]

hey guys i got myself a Suzuki GN 125 im not great with engines and wanted to see if i could find any explanations for my troubles here. i cant seem to get the bike to go top speed it always drops of at 40 sometimes it stays there sometimes my power drops to 30 also hill climbs reduce speed further, one more issue is that when im in 5th sometimes the throttle will lock and the speed will stay fixed. the only way ive found to break this is by pulling the clutch in. any pointers and help would be fantastic as im disgustingly poor and need this bike to basically keep my life together, thanks guys

[Alpineandy]

Do you think that maybe this question would be better in the 'workshop' section?
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The above comment isn't necessarily the truth and anyone that says it is, is only correct if it's the truth or they're bigger than me.

[Rogerborg]

Replace the oil with the cheapest 10W40 that you can find at your local supermarket. Clean the air filter or replace if it's truly manky or damaged. Clean the spark plug and check its condition and the gap. Check the chain tension and lubricate the chain. Check that neither brake is binding and that the wheels rotate freely. Disconnect the throttle cable at both ends, check that the throttle grip is free to rotate and that the cable can be pulled through the inner smoothly in both directions, lubricate it with silicone lube or clean engine oil, replace.

But that's so much work. Can't you just tell me the one thing I need to do?
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Biking is 1/20th as dangerous as horse riding.
GONE: HN125-8, LF-250B, GPz 305, GPZ 500S, Burgman 400 // RIDING: F650GS (800 twin), Royal Enfield Bullet Electra 500 AVL, Ninja 250R because racebike

[wodge]

Are you changing up to soon? It's a 125, you need Revs, lots of em to make progress. If you change up to early the engine bogs down and never gets to where the power is.
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nolidge iz pouwur.
Yamaha RXS100 RS100