Recent content by Foil

Just an update to move things along. I did end up buying a new piston (b) to go along with the damaged cylinder. I've put around 10 hours on it (about 4 at almost race pace) and everything sounds/feels pretty good. I will keep the older/worn out cylinder as a core, but the piston slap was...

Thanks for the feedback. Just got a few words back from motocrosscenter. They did refund the bearing kit + gaskets, but the rest. Well, it is what it is.

Yep, that spot is chipped all the way to the aluminium. The scratches aren't quite as bad, but you can definitely feel them with a nail. Keep in mind that these pictures were taken after a clean and a stone hone, so it won't get better than it is. Like I said, from assembly to failure was...

Howdy. I posted this up on thumpertalk as well, but this forum gets more traction on the gasgas stuff. I need some opinions about something that will never have an ideal answer. Long story short, I swapped out the piston and main bearings at around 600 hours and within 4-5 hours...

Currently I'm running some synthetic 5wt fork oil in the clutch master/slave and dexron IV in the gearbox. The warm drag is about as good as it's ever been - will now usually start in first with the clutch pulled in with the button. Kicking was never a problem. There's still some slight drag...

I've tried some 10w40 motul oil, then some synth 5w30 on my 2018 (19) rc300 and the drag was about as bad as my old dr350 which locked up the rear wheel in first, and second gear, no matter what. Up until I welded the bendix and the starter fried I flushed the oil with some atf twice and the...

Usually I take a look at pistons trough the exhaust. If the wear resistant coating is gone, then the lid as to come off. Popping the cylinder out of these ec's really isn't that bad either. I think I went from an open engine (when I replaced the piston) to a running bike in about an hour.

I'd take a look at the piston/cylinder. My bike made a knocking noise and it turned out to be piston slap. I replaced the cylinder and I *think* there's still a bit of slap at certain situations.

Aight, just a follow up. The piston and gasket kit showed up last friday, so as soon as I could get off work, I threw those on. Vertex b piston (a bit looser than it should be, but oh well) and a gasket kit for about 200?. Not great, not terrible. The bike now has a LOT more compression and...

Sounds like an air leak.My rmx 250 would do something similar - poor idling, low power, it would idle really high, until put it in first and slipped the clutch a bit. After lots of head scratching, it turned out to be a slight leak in the base gasket and a decent one in the flywheel side oil...

About this. My frame is actually a VTR4E3000J are those not affected by this recall?

Just thought I'd share the workshop manual for the 19 model year. Had to do some digging, but here it is. https://drive.google.com/file/d/19yA341TW5AH4U0nbKjFFZKeGjtRaqI8_/view?usp=sharing

From what I can tell in the cylinder/piston, I think the piston probably seized and then came loose. Maybe high rpms for too long? Maybe forgot to mix oil in the gas? I don't know how long the piston was slapping around (I certainly didn't do it any favors with the sunday ride), so anything is...

Well, the plot thickens. Turns out that the new-ish piston is actually a piece of trash. Front to back it measured about 71.4mm, so there's the noise - piston slap. The cylinder has some marks on it, but nothing that I can feel with a finger nail. So, what do you guys think? Run one...

Hi; So I just bought a 2018(19 model year with the different powervalve adjustment) EC300 with about 130 hours on it (the trip computer shows 105, but the seller claims it was changed out about 30 hours in). It supposedly also has a new-ish piston - but you all know how that goes. The bike...