Odd issue starting my BTX200

[Aerindel]

I see it as people not wanting to learn why something isn't working. They just want it to work. Minibikes are a hobby and something you tinker with. Figuring out the why is part of the fun of having them as a hobby. It can get annoying, but it is rewarding when you get a bike running right.

That's why you see so many posts on Reddit with people just wanting all the info given to them. They don't want to do any of the leg work to try and figure things out for themselves. That's a huge reason why I quit posting in the subs on there. I'd tell them what they need to buy and they'd reply back wanting links without so much as a thanks. Also getting told you're wrong for doing things the right way got old pretty quick. I'm an adult and I have money for toys so I don't do things the cheapest way possible. I do them the correct/safest way. Can you do X? Sure. Should you do X? Absolutely not.

Well, people do get into hobbies in different ways. I don't really like working on motors, I prefer them just to work.

However, welding new handlebars, fabricating new fenders, etc, that I like. I find the guys who have highly modified engines in totally stock chassis probably as funny as they would find me in a bone stock engine with a highly modified chassis.

 

[sparkwizard]

Before you give up on it, or take it apart, let me ask another question. Is the oil full and clean? Sometimes if the oil gets all black and nasty; or if it has never been changed since it was new, the little metal particles that do break off, fall into the oil and, honestly, they can make the compression release stick. It might not be a heat thing, but it might be a dirty oil problem. The little flyweight on the side of the cam gear can get stuck if a metal shaving gets between the cam gear and the CR fly weight. Maybe try changing your oil and LOOKING at the old oil as it drains. Metal particles are normal in break in oil. They shed particles while they break in. If those particles stay in there, they can get into your CR mechanism.

 

[Aerindel]

Before you give up on it, or take it apart, let me ask another question. Is the oil full and clean? Sometimes if the oil gets all black and nasty; or if it has never been changed since it was new, the little metal particles that do break off, fall into the oil and, honestly, they can make the compression release stick. It might not be a heat thing, but it might be a dirty oil problem. The little flyweight on the side of the cam gear can get stuck if a metal shaving gets between the cam gear and the CR fly weight. Maybe try changing your oil and LOOKING at the old oil as it drains. Metal particles are normal in break in oil. They shed particles while they break in. If those particles stay in there, they can get into your CR mechanism.

I've probably changed the oil five times since this started, including a few days ago, so that ship has sailed. It's break in period was in 2021? so its had gallons of oil run through it since then.

BUT, the first time I started having trouble I changed the oil and it was a milshake. Looked like a blown headgasket if it was a normal engine. I still don't know how it got that much water in the oil on an aircooled engine. I've never forded with it. I do suspect that issue had something to do with it, maybe it rusted?

 

[sparkwizard]

The cam has a little weight beside the gear that connects it to the crankshaft. That little weight flies out after the engine starts and negates the compression release. After the engine stops, there is a tiny steel spring that is supposed to pull that weight back to center and apply the compression release. I think you just figured it out. It sounds like that tiny spring and/or the steel weight got some rust on it.

 

[Aerindel]

That would be logical. I'll let you know what I find out when I get around to cracking the case open.

Any idea how I could get a bunch of water in the case? I mean, it has been left out uncovered in the rain a few times....but there shouldn't be a route for a lot of water to get into the oil should there?

 

[Aerindel]

Full disclosure, I did order a Predator 224....they are so cheap right now It just seemed like good insurance and the right time to do it, before the prices potentially explode and or availability drops. If nothing else, I have a project I can use a motor that size for regardless of what I do with the bike.

 

[sparkwizard]

The only easy way for water to enter the crankcase would be through the rubber vent tube in the valve cover. It should go to the air filter. If it is unhooked or the air cleaner was open, maybe water got in that way. It wouldn't take much. Maybe the heating and cooling over a couple of seasons caused enough condensation to build up in there. hard to tell. A spare engine is always a good idea, but as stated before, always plan to fix the other so you still have a spare.

 

[Aerindel]

The only easy way for water to enter the crankcase would be through the rubber vent tube in the valve cover. It should go to the air filter. If it is unhooked or the air cleaner was open, maybe water got in that way. It wouldn't take much. Maybe the heating and cooling over a couple of seasons caused enough condensation to build up in there. hard to tell

hmm, well, neither of those could be the case. I generally change oil every couple months and I've never noticed the tube disconnected...I was wondering if maybe water getting into the air filter through the top screw could have made its way to the case...I dunno.

 

[Strigoi]

Well, people do get into hobbies in different ways. I don't really like working on motors, I prefer them just to work.

However, welding new handlebars, fabricating new fenders, etc, that I like. I find the guys who have highly modified engines in totally stock chassis probably as funny as they would find me in a bone stock engine with a highly modified chassis.

I don't disagree with you at all there. I don't have the fab skills, but a friend of mine does.

Highly modified engines should be in a chassis that can handle them. I attached a pic of my old drag bike that was running 70+ in the 1/4 mile with my 250+ pound geared up ass on it. I sold the roller years ago but still have the engine. Need to get it going again so I can try to sell it. It's sitting in a project frame right now.

 

[Aerindel]

Swapped in a Predator 224 so I have something to ride.

I hate to say it, but even after I fix it, I think I will make the hi-sun a generator or something....the 224 is a lot nicer....it's worth it for the non-leaking gas cap alone.