Vento r3i keeps dying and starting later

[devilishlydo]

I've abused my poor Vento r3i zip and now it's punishing me. There were a couple of days where I put 20-40 miles on it in the course of a day. Near the end of that, the engine cut out on me while I was riding. I wasn't too shocked by this, and I was ready to give it up for dead. However, the next day, it started up again. It seemed to have lost some of it's oomph, but otherwise, it behaved normally. A few weeks later, it cut out again after a trip of only a couple of miles. Once again, after letting it sit for a day, it started up.

Now, I'm sure that something is wrong and it is in dire need of attention. What I don't know is what the likely problem is. Am I going to have to give it a Viking funeral or can it be saved without costing more than it's worth?

[dude]

Just guessing maybe a fuel problem. When it dies see if there is fuel in the float bowl.

[tango]

Sounds like you may be soft seizing. That's usually when you run lean (not enough fuel), the engine overheats and the aluminium piston expands more than the steel cylinder and the engine seizes. It will usually start up after it has cooled down (provided no major damage). This may be a sign that you are having fuel-flow issues at more open throttle settings. You may have a faulty carburettor (slightly clogged jets perhaps) or a faulty vacuum pet-cock (high engine speeds don't produce a lot of vacuum and may not allow the petcock to remain open enough for proper fuel flow). I suspect that you may have further questions regarding what I just said, so I'll allow you the opportunity to ask away! LOL!

[devilishlydo]

I hadn't even considered a fuel problem. It does seem to be overheating a bit, but I didn't realize that could be caused by a fuel-flow problem. Most of the 'abuse' I mentioned featured me going at near-top speed (before this happened, top speed was around 40mph, but now it's more like 30) for long periods of time.

If that's the case, is there an additive I can put into the fuel to clear out the clogs or does it need to be opened up and done by hand?

[tango]

I would say open it up and do it by hand. Let's say there's a piece of metal shaving that's clogging your main jet. The only thing that can dissolve metal is acid and that would also dissolve your entire scooter! Get your hands dirty, brother. That's the only way I trust!

As for the petcock, check to see if there are any holes in the vacuum tube that goes to it. Let us know if you need help finding the petcock and its hose.

[lbo]

If it's not soft seizing nor a fuel delivery issue then it could be possible that you are losing compression. My 2T nitro RC engines would act this way when they were getting worn out. Run great until they get up to temp, slowly lose power, and then just die until they cool down. Rinse lather repeat.