Posted: 02 May 2008 at 12:37am | IP Logged

Hi...

I've noticed that since I crashed my 90 it doesn't feel the same as it used to.

Whenever I fly the chopper doesn't seem to keep a constant headspeed and my GV-1 only reads 86% instead of 97%.

I also used an optical tach - just to see if the GV-1 was working correctly and the headspeed's were WAY too low. I set the GV-1 to 1950 in idle up 2 and the optical tach only measured +-1550.

Before the crash it seemed fine, I rebuilt the heli and changed blades, engine head etc..but it doens't fly like it did. I'm using an O.S 91SZ-H and Radix 710mm blades with a muscle pipe.

Can anyone give me an idea why my headspeed is not staying constant - could it be an engine related problem, a throttle servo problem or a blade pitch problem? When I checked the headspeeds I was hovering so it's doubtful its the pitch??

Your Help is greatly appreciated!!!

Thanks a lot.

Posted: 02 May 2008 at 8:02am | IP Logged

It sounds like you rebuilt the engine as well so frist Q is did it get rebuilt rite? Thin you wonder if its the pitch and yes it could be so check if at center stick you have 0 pitch and also 10+ and 10- so check all that and get back to me and let me know.

Posted: 02 May 2008 at 11:25pm | IP Logged

Also, check the clutch stack. If the clutch stack has a bad bearing it can rob the engine of power. On these little engines a little bit can mean a lot. Here's the bearing breakdown for this assembly:

PV0182: Clutch Bell bearing
PV0203: Starter shaft bearing - Upper, smaller one in the clutch base
PV0244: Pinion Bearing - Lower, larger one in the clutch base

When you mentioned the percentages of your governor, I presume you are talking about the signal strength from the magnet. Is there something going on there? Did your sensor position move from the crash?

Finally, when you mentioned that headspeed was measured lower than what the GV reads, is it also noticeably (audibly) lower?

 - Bert

Posted: 02 November 2009 at 12:18am | IP Logged

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