Vapor lock?

Stormswift · Post by **Stormswift** » Mon May 09, 2011 5:10 pm

This morning had a problem. Warmed up scoot, then was riding as usual, gaining speed. Next thing I know everything goes blank. Pushed scoot to the side street. Wated a moment and restarted it. Ran for about 2 miles then same thing. Restarted then kept idling it when at a stos or lights and made it OK to work. Wapor lock or bad batch of gas, anyone??

7ate9 · Post by **7ate9** » Mon May 09, 2011 5:17 pm

I had same problem on new scooter! Had my tank cleaned there was crap in the tank from the factorry. Look inside your tank w/ a light and see if you can see anything?

KABarash · Post by **KABarash** » Mon May 09, 2011 5:23 pm

Have you a 'vented' gas cap?

When I was having issues it was suggested to me (by Scooterworks' personnel) to leave the cap loose to see if that solved the issue. They then also sent me a new 'vented' cap.

ed85379 · Post by **ed85379** » Mon May 09, 2011 6:15 pm

I had a similar problem this morning on my brand new (180 miles) scooter. But it wasn't vapor lock. I popped the gas cap off to release pressure at the first sign of a problem. That is all it takes to relieve a vapor lock issue.

I had exhaust popping and then loss of power while riding, but not while idling. I'm guessing some bad gas, and presuming I can make it home, I'll fill it up and put some Seafoam in it. But I am also considering bringing it in for its first oil change/maintenance today before going home, though 180 miles is a bit early for that. Was planning on giving it 250-300 miles.

Maybe this day is just cursed for scooters.

Stormswift · Post by **Stormswift** » Mon May 09, 2011 11:54 pm

Here is what I noticed. The problem started when I pushed it to 40 mph this morning. This is when everything went blank. Usually my scooter runs like a Roadrunner. It is a 150 cc little beastie so it is pretty fast. This morning it was sort of slow. I am suspecting bad gas. I keep extra gas in the container just in case and yesterday I used it up. I think there may have been some crud on the bottom. I put seafoam in when I got home from work and ran the engine, rocked back and forth vs just idling. The loss of speed bothers me. Coming from work the bike lost power once. I restarted it and then keep it cautiously at 30 mph by its speedometer. (which is like 25 mph. Fortunately after 6 pm there is not much traffic . Towards the end of my ride home it felt like the power was really coming back. I was able to bring the bike up to 40+ mph gradually and it was performing like nothing happened. Tomorrow my mechanic is in so I will be calling. I think we need a "once over". It was not the experience I want to ever repeat.

Dooglas · Post by **Dooglas** » Tue May 10, 2011 12:58 am

Doesn't sound like the so-called "vapor lock" to me. Could well be some gas that had sat in a containor in the garage for too long or some debris in the gas.

Stormswift · Post by **Stormswift** » Tue May 10, 2011 1:23 am

Dooglas wrote:Doesn't sound like the so-called "vapor lock" to me. Could well be some gas that had sat in a containor in the garage for too long or some debris in the gas.

If any of the above is the case I am hoping Seafoam will take care of it. I plan to ran through this gas as soon as I can and fill up with fresh stuff. Hopefully I will flush out whatever crud accumulated there. Men, these bikes are sensitive!!!!! I put Seafoam in regularly into the gas tank. Now keeping my fingers crossed. I don[']t know what else to do. I did e-mail my mechanic. Hopefully though this is a temporary problem. bad gas related and will be resolved as soon as this stuff is used up. Needless to say, I am driving tomorrow

Dooglas · Post by **Dooglas** » Tue May 10, 2011 1:33 am

Assuming this is a gas related issue and SeaFoam (and new gas) doesn't resolve it, the next step up the ladder is probably cleaning or replacing the carburetor jets. A little bit of crud in one of the jets can really cause drastic changes in a smooth running engine.

Stormswift · Post by **Stormswift** » Tue May 10, 2011 11:22 pm

I spoke with my mechanic today: he is totally backed up with repairs. One thing he suggested is that this may be bad gas so riding close to home after Seafoaming the gasoline is not a bad idea. I had half a tank of fuel which I treated with Seafoam yesterday. Today I went to the gas station and put some more gas in, the most expensive kind and added more seafoam. I cannot say performance is optimal (or I may be too scared to push the bike too hard). But today there was no stalling. I vented the tank before ride to work and before riding home. This second time when I took the cap off there was a definite "hiss'. I am going to keep adding Seafoam and keep riding, keeping speed at 35 mph. I did push the speed a little at the end again and all went well so far. I hope once all of this gas is cycled out things will go back to normal

Dooglas · Post by **Dooglas** » Tue May 10, 2011 11:45 pm

Sounds like you are making progress. One thing to know. Seafoam, or Stabil or whatever, will not resurrect bad (old) gas. If you have some gas that has been sitting in a gas can for several months, best to dump that out, or put it in your car and burn it up. (stuff like Stabil only works to preserve gas if you add it while the gas is fresh)

Hellvis · Post by **Hellvis** » Tue May 10, 2011 11:46 pm

Stormswift wrote:I spoke with my mechanic today: he is totally backed up with repairs. One thing he suggested is that this may be bad gas so riding close to home after Seafoaming the gasoline is not a bad idea. I had half a tank of fuel which I treated with Seafoam yesterday. Today I went to the gas station and put some more gas in, the most expensive kind and added more seafoam. I cannot say performance is optimal (or I may be too scared to push the bike too hard). But today there was no stalling. I vented the tank before ride to work and before riding home. This second time when I took the cap off there was a definite "hiss'. I am going to keep adding Seafoam and keep riding, keeping speed at 35 mph. I did push the speed a little at the end again and all went well so far. I hope once all of this gas is cycled out things will go back to normal

I hope all goes well, it sure does sound like a batch of bad gas. I always hope that I don't get bad gas. So far so good. Hope I didn't jinx it now.

Stormswift · Post by **Stormswift** » Wed May 11, 2011 12:47 am

Since whatever it was is already in my scooter tank not much I can do but hope it works itself out of the system without clogging up anything vital. I do think that scooter not stalling today was a good sign. I am definitely going to make sure I only fuel up at the gas station from now on. The container was very convenient especially in the mornings but I will just have to fuel up ahead of time. Or drive.

Stormswift · Post by **Stormswift** » Wed May 11, 2011 4:20 pm

today stald again twice , this time with accompanying popping noises. After that it appeared to run a little better. I know I cannot take it above 30 while it is warming up. I guess it needs to "cough up" whatever it is "choking" on. I am still hoping to get through this without major repairs and $$$

Stormswift · Post by **Stormswift** » Wed May 11, 2011 4:23 pm

today stald again twice , this time with accompanying popping noises. After that it appeared to run a little better. I know I cannot take it above 30 while it is warming up. I guess it needs to "cough up" whatever it is "choking" on. I am still hoping to get through this without major repairs and $$$

Dooglas · Post by **Dooglas** » Wed May 11, 2011 6:01 pm

Stormswift wrote:I am definitely going to make sure I only fuel up at the gas station from now on. The container was very convenient especially in the mornings but I will just have to fuel up ahead of time. Or drive.

I frequently fuel up from a can of gas I keep in the garage. With three scooters we usually go through that gas can in a week or so. In the off season I treat the can with Stabil when it is first filled. I have never had a problem in years of doing this.

JHScoot · Post by **JHScoot** » Wed May 11, 2011 7:24 pm

check the valves, maybe?

babblefish · Post by **babblefish** » Wed May 11, 2011 8:01 pm

Stormswift wrote:today stald again twice , this time with accompanying popping noises. After that it appeared to run a little better. I know I cannot take it above 30 while it is warming up. I guess it needs to "cough up" whatever it is "choking" on. I am still hoping to get through this without major repairs and $$$

Hairballs? Sorry, I'm such a cat person...

When was the last time it had it's valves adjusted?

Stormswift · Post by **Stormswift** » Wed May 11, 2011 11:20 pm

Dobby is only a bit over 600 so it had its 500 mile /300 km service (the 1st one required oil change in the fall before being winterized). I don't know if anything was checked during that time. I've had it for under 2 years, got it new and it is still under warranty. Until last fall I did not do much riding at all because I did not yet have my license. This year I am riding to work and after 1 week this is when it started.

Stormswift · Post by **Stormswift** » Wed May 11, 2011 11:22 pm

babblefish wrote:
Stormswift wrote:today stald again twice , this time with accompanying popping noises. After that it appeared to run a little better. I know I cannot take it above 30 while it is warming up. I guess it needs to "cough up" whatever it is "choking" on. I am still hoping to get through this without major repairs and $$$
Hairballs? Sorry, I'm such a cat person...

When was the last time it had it's valves adjusted?

More like constipation based on the sounds it made this morning

kayan · Post by **kayan** » Sat Jul 07, 2012 4:56 am

Stormswift wrote:today stald again twice , this time with accompanying popping noises. After that it appeared to run a little better. I know I cannot take it above 30 while it is warming up. I guess it needs to "cough up" whatever it is "choking" on. I am still hoping to get through this without major repairs and $$$

I'm going through this EXACT problem: scooter runs fine under all conditions except when it is hot outside, the engine gets hot, and I am under high throttle conditions. From the research that I have done so far and the symptoms that I see, I tend to believe it has to do with the auto-choke malfunctioning at high temperatures. This would explain why when I lose power, there is exhaust backfire from a too-rich mixture of exhaust entering the exhaust pipe. So I actually think it is an electrical problem of delivering the right signal to the auto-choke system, however, there are still several possibilities.

michelle_7728 · Post by **michelle_7728** » Sat Jul 07, 2012 5:29 am

Which Buddy do you have? This may be obvious to those of us who are mechanically inclined...

(meaning I'm not!)

I ask, because I thought I remembered hearing that there was a potentially free computer retweak for the 170s due to something or other (I don't have one, or I would have paid closer attention).