VVRC 40cc Twin

[Ohio AV8TOR]

Is this something current owners need to be concerned about?

I can't answer that because everyone is different. I sold my 40 with my EF MXS to get my DA70 and 91 Extra but if I still had it I would at least get an email to Denny as his customer service is extremely good to be kept in the loop. I had a problem with mine being an early motor but the replacement motor was flawless and had more power/rpm than my first. It does no seem wide spread as there are a lot with a lot of fuel through them.

 

[David Shriver]

I bought one used on an EF 78" Extra. I had some issues with a loose muffler, but now that it is fixed the engine has proven very reliable for me. The plane had about 200 flights when I bought it, and I've put another 100-120 on it since then. It starts easy and runs well. I'm turning a 20x9 at 6950 on the ground. I've seen some of the VVRC 40s turning slightly higher so I might be leaving a few RPMs behind by being slightly rich.

 

[witchfingers]

Mine is running great......for now. Oh well, if she gives up the ghost I know vv will treat me right. No worries here.

 

[Flyingjon]

I have been putting a few flights on mine now and then, maybe an average of 8-10 per month and I've been happy with the eu it's been running. I put bowman rings in it from the start and have been running Stihl Ultra HP. I'm going to estimate I have probably 90-100 flights on it.

My question is; how much compression should I have? It seems very mushy, as I can easily push it through compression without much resistance. I can't complain about power, because I have a falcon 20x9 pulling 21-22 lbs of thrust. It has good response and otherwise runs normal, but my buddy's EME 70 is solid when you push it up against compression.

 

[Ohio AV8TOR]

When I had th 40 twin I always felt my compression felt mussy as well. It made it very hard for me to hand start but started instantly with an electric starter. I never asked about it because it ran so well.

 

[witchfingers]

I used to have to use an electric starter but after I started pulling the choke down hard to seat it, I have no problems hand starting it. Mine has less compression than a single cylinder but I think that's normal.

 

[ryan_m]

Is VVRC still selling this motor? I didn't see it up on their site.

 

[Flyingjon]

Refer to post #129.

 

[witchfingers]

My 40 is now ripping the 20x8 prop so I will have to step it up a pitch or a size.

 

[David Shriver]

I'm running a falcon 20x9 on mine. I see 6950 on the ground, but in-flight telemetry is showing a max of about 8400. I'm not thrilled with the 20x9 though. I'd like something a bit slower, but Falcon doesn't have a 21x8 which I think would be perfect. I tried a 22x8 but it was too much prop.